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. 2021 Aug 7;25(1):22–32. doi: 10.1007/s10120-021-01225-1

Sex differences in tumor characteristics, treatment, and outcomes of gastric and esophageal cancer surgery: nationwide cohort data from the Dutch Upper GI Cancer Audit

Marianne C Kalff 1,, Anna D Wagner 2, Rob H A Verhoeven 3,4, Valery E P P Lemmens 3,5, Hanneke W M van Laarhoven 4, Suzanne S Gisbertz 1, Mark I van Berge Henegouwen 1,; the Dutch Upper GI Cancer Audit group
PMCID: PMC8732809  PMID: 34365540

Abstract

Background

Sex differences in clinicopathological characteristics, treatment, and postoperative outcomes of gastric and esophageal cancer are largely undefined. This study aimed to compare tumor and treatment characteristics and outcomes of gastric and esophageal cancer surgery between male and female patients.

Methods

Patients after elective surgery for primary esophageal (EAC) or gastric adenocarcinoma (GAC) registered in the Dutch Upper GI Cancer Audit between 2011 and 2016 were included. The primary endpoint, 5-year relative survival with relative excess risk (RER), i.e., adjusted for the normal life expectancy, was compared between male and female patients with EAC and GAC.

Results

In total, 4937 patients were included (75% male) with a mean age of 66 years. cT and cN-stages showed a similar distribution in male and female patients. In females, antrum GAC was more frequent (47% vs. 38%, p < 0.001). Female patients with EAC less frequently received neo-adjuvant treatment (OR = 0.60, 95% CI 0.38–0.96, p = 0.033). For GAC, less postoperative morbidity (33% vs. 38% p = 0.017) and less re-interventions (12% vs. 16%, p = 0.008) were observed in females, although they had inferior 5-year relative survival (49% vs. 56%, RER = 1.31, 95% CI 1.09–1.58, p = 0.004). No differences in relative survival of EAC were observed.

Conclusions

In addition to significant sex differences in tumor location, female patients with esophageal adenocarcinoma less frequently received neo-adjuvant therapy, and female patients with gastric adenocarcinoma had inferior relative survival. Further consideration and exploration of sex differences in surgical treatment and outcomes are necessary to improve tailored treatment and outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10120-021-01225-1.

Keywords: Gastric cancer, Esophageal cancer, Gastrectomy, Esophagectomy, Survival

Introduction

The incidence of gastric and esophageal cancer is substantially higher in male patients [1, 2]. For both gastric and esophageal adenocarcinomas, behavioral risk factors, such as obesity or exposure to carcinogens like tobacco smoking, do not entirely explain the sex disparity in incidence seen across multiple populations [35], thus strongly suggesting sex differences in susceptibility and/or biology for this type of cancer. In fact, increasing evidence suggests a sexual dimorphism in cancer biology, and sex-biased molecular signatures have been observed across multiple tumor types [610].

Perioperative chemotherapy and neo-adjuvant chemoradiotherapy combined with surgical resection are the mainstays of curative treatment for gastric and esophageal cancer, respectively [11, 12]. While the impact of the patients’ sex on the balance between efficacy and toxicity of systemic treatments in oncology has gained more attention in recent years [13, 14], its impact on surgical outcomes has been investigated less frequently. Previous studies have shown that for both gastric and esophageal cancer, male patients more frequently undergo surgery [15, 16]. Furthermore, in gastric cancer patients treated exclusively with gastrectomy, the Dutch D1D2-trial showed a superior survival in female patients after an extended (D2) lymphadenectomy [17]. In addition, the CROSS-trial, evaluating the benefit of neo-adjuvant chemoradiotherapy versus surgery alone for esophageal cancer, portrayed a more pronounced treatment effect in males [18].

As a result of the difference in incidence, only relatively small absolute numbers of female patients are included in many clinical trials concerning gastric and esophageal cancer treatment, impeding any firm conclusions concerning the magnitude of the treatment benefit in female patients. In the context of the limited data, the aim of this study was to examine sex differences in tumor and treatment characteristics, and outcomes of gastric and esophageal cancer surgery in a large nationwide cohort study, to provide ground for further individualization of gastric and esophageal cancer treatment.

Materials and methods

Data for this study were acquired from the national Dutch Upper GI Cancer Audit (DUCA) database. In the Netherlands, caregivers are obliged to register all patients with gastric and esophageal cancer with intended resection in the DUCA registry. This audit is part of the Dutch Institute for Clinical Auditing (DICA), and was initiated in 2011 with the aim of providing independent information on the quality of care. Validation of case completeness (99.8%) and accuracy (94–100%) has been performed [19, 20]. Data registration for audit purposes is limited to 30 days after surgery, or when extending over 30 days, the duration of the initial hospital stay. To allow research initiatives regarding survival, DUCA-data were linked with data of the Dutch national health care insurance registry (Vektis). As health care insurance is mandatory for all Dutch inhabitants, this registry includes 99% of the Dutch population. Date of death is registered given that insurance ends as the patient dies. The process of matching datasets and subsequent validation has been described recently [21]. Data collected from the combined dataset consisted of baseline patient characteristics, tumor and treatment specifications, and histopathological and postoperative outcomes, and vital status.

This study was approved by the scientific committee of the DUCA. No informed consent, opt-out procedure, or ethical approval was required under Dutch law. This paper complies with the STROBE guidelines for observational cohort studies [22].

Patients and treatment

All patients with a primary esophageal or gastric adenocarcinoma that underwent a surgical procedure with curative intent between 2011 and 2016 were retrieved from the DUCA dataset. Patients with missing information on sex, and patients that underwent a salvage or non-elective procedure were excluded. All patients underwent surgery with curative intent and remained in the analyses if, due to unforeseen circumstances (e.g., metastatic disease and tumor extent), no surgical resection was performed. The performed surgical procedures were a transthoracic or transhiatal esophagectomy, a total or partial gastrectomy, or no resection (i.e., bypass or surgical exploration). Multimodal treatment regimens consisted of neo-adjuvant or perioperative treatment (combined neo-adjuvant and adjuvant treatment).

Outcome data and definitions

The primary outcome was 5-year relative survival after gastric and esophageal cancer surgery. Secondary outcomes were differences in tumor characteristics, treatment specifications, short-term morbidity and mortality, and oncological outcomes such as response to neo-adjuvant treatment. Relative survival was defined as the observed overall survival divided by the age, year, and sex-matched expected overall survival of the general Dutch population [23]. Clinical and pathological TNM staging was defined by the eighth TNM staging edition. Survival was calculated as the interval (in months) from the date of surgery to the date of death or last follow-up (Vektis database last follow-up: 1st of September 2017).

Statistical analysis

For all outcomes investigated, stratification was performed by tumor location in esophageal and gastric adenocarcinoma. Primary and secondary endpoints were subsequently compared between male and female patients. Mann–Whitney U or Student’s t test for continuous variables, and χ2 test for categorical variables were used when applicable.

In case of treatment differences between male and female patients, regarding the application of neo-adjuvant or perioperative treatment, transhiatal or transthoracic esophagectomy for esophageal tumors, and partial or total gastrectomy for gastric tumors, additional multivariable logistic regression analysis was performed to assess whether differences remained after adjustment for clinical parameters thought to affect treatment probability (age, ASA-class, the presence of cardiac, pulmonary, vascular or diabetic comorbidities, clinical T and N stage, tumor differentiation, histopathological subtype, tumor location, and year of surgery), resulting in odds ratios (OR) with 95% confidence intervals (95% CI).

As the general life expectancy is known to differ between sexes, relative survival was assessed as the overall survival observed in the gastric and esophageal cancer patient cohort, divided by the expected survival in the general Dutch population matched on age, sex, and year, according to the method of Pohar Perme [23]. To assess the association between sex and risk of death, multivariable relative excess risk (RER) with 95% CI was estimated using the relative survival, adjusted for confounders known to affect survival (age, ASA-score, clinical T and N stage, and tumor sub-location).

As pre-menopausal female sex hormones, i.e., estrogen, are thought to have a protective effect reducing the risk and invasiveness of gastric and esophageal adenocarcinoma, subgroup analyses comparing male patients to female patients ≤ 55 and > 55 years were performed [6, 2427].

Few missing data were present in clinical variables and therefore handled by complete case analyses. STATA Version 14.2 (StataCorp, College Station, TX, USA) was used to assess relative survival, and SPSS Statistics Version 26.0 (Armonk, NY) was used for further statistical analysis. Two-sided p values of less than 0.05 were considered statistically significant.

Results

Baseline characteristics

In total, 2865 patients with esophageal and 2072 patients with gastric adenocarcinoma were included, of whom 74.8% were male (Fig. 1; Table 1). More cardiac comorbidities were observed in male patients in both groups. No sex differences were observed in the distribution of clinical T and N stage. For gastric adenocarcinoma, more poorly differentiated tumors and more diffuse type tumors were observed in females (69.4% vs. 56.5%, p < 0.001; 48.6% vs. 34.9%, p < 0.001, respectively), who also had tumors more frequently located in the antrum (46.7% vs. 37.5%), while males more often had tumors located in the fundus (10.9% vs. 5.0%, p < 0.001; Fig. 2).

Fig. 1.

Fig. 1

Flowchart of study inclusion. *Multiple reasons for exclusion may apply for one patient

Table 1.

Baseline characteristics of male and female patients with gastric and esophageal cancer

Characteristics Esophageal cancer Gastric cancer
Male Female p Male Female p
n = 2387 n = 478 n = 1304 n = 768
n % n % n % n %
Mean age Years (SD) 64.6 9.1 65.0 9.3 0.454 68.6 11.0 67.7 12.9 0.115
Age ≤ 55 year 372 15.6 75 15.7 0.959 158 12.1 146 19.0 < 0.001
Mean BMI Kg/m2 (SD) 26.4 4.0 26.8 5.6 0.114 25.3 4.1 25.1 4.9 0.197
ASA score I 416 17.6 71 15.1 0.515 170 13.2 123 16.3 0.209
II 1422 60.1 285 60.5 726 56.2 422 55.8
III 519 21.9 112 23.8 385 29.8 206 27.2
IV 11 0.5 3 0.6 11 0.9 5 0.7
Comorbidity Pulmonary 418 17.5 87 18.2 0.703 244 18.7 91 11.9 < 0.001
Cardiac 617 25.8 89 18.7 0.001 449 34.4 177 23.1 < 0.001
Vascular 886 37.1 203 42.6 0.025 522 40.0 283 37.0 0.171
Diabetes 402 16.8 82 17.2 0.852 217 16.6 123 16.1 0.739
cT stage Tis 9 0.4 0.076 7 0.7 3 0.5 0.363
T1 115 5.1 37 8.1 76 8.0 57 10.4
T2 445 19.6 86 18.8 252 26.3 133 24.2
T3 1644 72.2 321 70.2 541 57.0 305 55.6
T4 63 2.8 13 2.8 73 7.7 51 9.3
cN stage N0 829 36.0 195 42.5 0.115 648 58.1 378 57.6 0.927
N1 951 41.3 170 37.0 303 27.2 176 26.8
N2 427 18.6 75 16.3 108 9.7 63 9.6
N3 68 3.0 15 3.3 15 1.3 12 1.8
N +  26 1.1 4 0.9 41 3.7 27 4.1
Differentiation Good 866 55.2 163 51.7 0.267 437 43.5 178 30.6 < 0.001
Poor 704 44.8 152 48.3 567 56.5 404 69.4
Histological subtype Intestinal 788 81.2 160 82.1 0.562 515 57.7 239 45.0 < 0.001
Diffuse 116 12.0 19 9.7 311 34.9 258 48.6
Mixed 66 6.8 16 8.2 66 7.4 34 6.4
Clinical tumor location Cervical 2 0.1 0.597
Proximal 4 0.2 2 0.4
Middle 81 3.4 21 4.4
Distal 1527 64.4 301 63.1
GEJ 757 31.9 153 32.1
Fundus 136 10.9 37 5.0 < 0.001
Corpus 389 31.2 232 31.7
Antrum 468 37.5 342 46.7
 Belongs to tumor location Pylorus 104 8.3 64 8.7
Entire stomach 73 5.8 53 7.2
Gastric remnant 78 6.3 5 0.7

Percentages for the variables are calculated out of the total number of actual results available, excluding the missing values. Percentages may not add up to 100% due to rounding

ASA American Society of Anesthesiologists, BMI body mass index (kg/m2), cN clinical N stage, cT clinical T stage, GEJ gastro-esophageal junction, SD standard deviation

Fig. 2.

Fig. 2

Distribution of tumor location and histology for male and female patients with gastric and esophageal cancer. Numbers represent the percentages of tumor location for male and female patients. GEJ gastro-esophageal junction

Treatment characteristics

Females with esophageal adenocarcinoma less often received neo-adjuvant treatment (78.1% vs. 85.6%; OR 0.60, 95% CI 0.38–0.96, p = 0.033; Table 2), which less often consisted of chemoradiotherapy compared to neo-adjuvant treatment regimens in male patients (90.5% vs. 93.9%, p = 0.019). Less females with gastric adenocarcinoma received perioperative treatment (35.2% vs. 40.3%, p = 0.024), although not significant when adjusted for clinicopathological factors (OR 0.75, 95% CI 0.52–1.06, p = 0.105).

Table 2.

Treatment characteristics of male and female patients with gastric and esophageal cancer

Characteristics Esophageal cancer Gastric cancer
Male Female p Male Female p
n = 2387 n = 478 n = 1304 n = 768
n % n % n % n %
Neo-adjuvant treatment 2033 85.6 370 78.1 < 0.001 298 23.0 165 21.6 0.463
Chemotherapy 125 6.1 35 9.5 0.019 275 92.3 159 96.4 0.083
CRT 1908 93.9 335 90.5 23 7.7 6 3.6
> 80% completed 1948 96.8 351 95.9 0.396 200 67.2 110 67.5 0.956
Perioperative treatmenta 133 5.6 34 7.1 0.188 499 40.3 260 35.2 0.024
Procedure type Transthoracic 1357 57.0 234 49.3 < 0.001 10 0.8 1 0.1 0.007
Transhiatal 876 36.8 201 42.3 13 1.0 4 0.5
Total gastrectomy 62 2.6 11 2.3 531 41.1 267 35.0
Partial gastrectomy 2 0.1 4 0.8 631 48.8 425 55.8
No resectionb 84 3.5 25 5.3 107 8.3 65 8.5
Approach of surgery Open 1087 45.6 230 48.1 0.448 932 71.9 528 69.4 0.222
MIS 1251 52.5 242 50.6 364 28.1 233 30.6
Hybrid 44 1.8 6 1.3 NA NA
Year of surgery 2011 412 17.3 87 18.2 0.247 193 14.8 103 13.4 0.377
2012 444 18.6 105 22.0 213 16.3 144 18.8
2013 459 19.2 94 19.7 286 21.9 181 23.6
2014 514 21.5 99 20.7 342 26.2 181 23.6
2015 558 23.4 93 19.5 270 20.7 159 20.7

Percentages for the variables are calculated out of the total number of actual results available, excluding the missing values. Percentages may not add up to 100% due to rounding

CRT chemoradiotherapy, MIS minimally invasive surgery, NA not applicable

aConsisting of both neo-adjuvant and adjuvant treatment

bSurgery for intended curative resection, due to metastatic disease, tumor extent, or deterioration of the condition of the patient during surgery, no surgical resection was performed

For both esophageal and gastric adenocarcinoma, the type of surgical procedure performed differed. For esophageal adenocarcinoma, more female patients underwent a transhiatal resection (42.3% vs. 36.8%, p < 0.001), and for gastric adenocarcinoma, more female patients underwent a partial gastrectomy (55.8% vs. 48.8%, p = 0.007). These differences did not remain significant after adjustment for clinicopathological factors (EAC: OR 0.73, 95% CI 0.50–1.08, p = 0.119; GAC: OR 1.23, 95% CI 0.83–1.81, p = 0.300). No sex difference was observed for open or minimally invasive approaches.

Postoperative and histopathological outcomes

A microscopically radical resection (R0) was equally obtained in both sexes (Table 3). Pathological T stage differed for patients with gastric adenocarcinoma, with lower pT stages in female patients (pT3: 37.0% vs. 41.8%, p = 0.014). pN stage differed between male and female patients with esophageal adenocarcinoma, while (positive) lymph-node harvest showed no difference. The responses to neo-adjuvant therapy were equally distributed. Only for patients with gastric adenocarcinoma, postoperative morbidity differed; with more complications in general (38.1% vs. 32.9%, p = 0.017), more pulmonary complications (15.7 vs. 10.8%, p = 0.002), more anastomotic leakages (7.5% vs. 5.1%, p = 0.031), and more re-interventions (16.2% vs. 11.9%, p = 0.008) in male patients. Postoperative morbidity was higher after total versus partial gastrectomy (41.9% vs. 34.4%, p = 0.001). Short-term mortality was comparable between male and female patients in both groups.

Table 3.

Pathological and postoperative outcomes of male and female patients with gastric and esophageal cancer

Characteristics Esophageal cancer Gastric cancer
Male Female p Male Female p
n = 2387 n = 478 n = 1304 n = 768
n % n % n % n %
Lymph nodes, median (IQR) Number 18 13–24 17 12–24 0.636 18 13–26 19 13–28 0.069
Positive 0 0–2 0 0–2 0.185 1 0–5 1 0–5 0.717
(y)pT stage T0 373 16.9 73 16.9 0.815 67 5.7 25 3.6 0.014
Tis 23 1.0 6 1.4 13 1.1 6 0.9
T1 396 17.9 85 19.6 161 13.8 130 18.8
T2 450 20.3 79 18.2 184 15.7 117 16.9
T3 935 42.3 185 42.7 489 41.8 256 37.0
T4 35 1.6 5 1.2 256 21.9 158 22.8
(y)pN stage N0 1322 57.7 280 62.2 0.005 538 45.4 320 46.1 0.486
N1 474 20.7 64 14.2 218 18.4 122 17.6
N2 307 13.4 75 16.7 207 17.5 107 15.4
N3 188 8.2 31 6.9 221 18.7 145 20.9
(y)pM stage M0 2192 98.3 429 98.2 0.800 1049 93.9 616 94.2 0.812
M1 37 1.7 8 1.8 68 6.1 38 5.8
Resection R0 2139 93.7 413 93.2 0.714 1032 88.6 595 87.9 0.654
R +  144 6.3 30 6.8 133 11.4 82 12.1
Response to neo-adjuvant treatment None 231 12.9 55 16.3 0.239 187 36.1 108 37.9 0.065
Partial 1214 67.6 219 64.8 272 52.5 159 55.8
Complete 352 19.6 64 18.9 59 11.4 18 6.3
Postoperative complication Yes 1350 56.7 273 57.2 0.845 496 38.1 252 32.9 0.017
Leakage 444 18.7 76 15.9 0.333 98 7.5 39 5.1 0.031
Pulmonary 686 28.8 144 30.2 0.553 205 15.7 83 10.8 0.002
Cardiac 289 12.1 57 11.9 0.904 78 6.0 35 4.6 0.169
Re-intervention 505 21.4 103 21.6 0.907 209 16.2 91 11.9 0.008
Median ICU stay (IQR) 2 1–4 2 1–5 0.618 0 0–1 0 0–1 0.135
Median LOS (IQR) 12 9–19 13 9–19 0.026 9 7–14 9 7–13 0.970
Short-term mortalitya 79 3.4 18 3.9 0.579 74 5.8 33 4.4 0.172

Percentages for the variables are calculated out of the total number of actual results available, excluding the missing values. Percentages may not add up to 100% due to rounding

ICU intensive-care unit, IQR interquartile range, LOS length of stay, pN pathological N stage, pT pathological T stage, pM pathological M stage

aShort-term mortality is the combined 30-day and in-hospital mortality

Survival

For females with gastric cancer, 5-year relative survival was inferior to male patients (48.6% vs. 55.8%), also when adjusted for clinicopathological factors (RER 1.31, 95% CI 1.09–1.58, p = 0.004). No statistically significant differences in 5-year relative survival were observed between male and female patients with esophageal adenocarcinoma (52.4% vs. 54.2%; RER 1.01, 95% CI 0.86–1.19, p = 0.891; Fig. 3).

Fig. 3.

Fig. 3

Relative survival of male and female patients with esophageal and gastric adenocarcinoma. a Relative survival of male and female patients with esophageal adenocarcinoma. b Relative survival of male and female patients with gastric adenocarcinoma. RER relative excess risk

Subgroup analysis

While the mean age at diagnosis was comparable between sexes, gastric cancer patients ≤ 55 years were more frequently of female sex (19.0% vs. 12.1%, p < 0.001). Young female gastric cancer patients were more frequently diagnosed with poor tumor differentiation (84.3% vs. 68.0%, p = 0.004), and diffuse-type tumors (72.5% vs. 50.4%, p = 0.004) compared to males (Online Resource 1). For older female gastric cancer patients, percentages of poor differentiation (66.0% vs. 56.5%, p < 0.001) and diffuse subtype (42.9% vs. 34.9%, p = 0.018) remained significantly higher compared to males, although the inter-sex difference was less pronounced.

For both female esophageal cancer patients ≤ 55 and > 55 years, relative survival was comparable to male patients (Online Resource 2), while for female gastric cancer patients, relative survival was inferior to males, especially for those ≤ 55 years (RER 1.41, 95% CI 1.03–1.94, p = 0.033).

Discussion

While increasing evidence suggests an impact of the patients’ sex on the balance between efficacy and toxicity of systemic treatments in oncology [13, 14], its impact on surgical treatment choices and outcomes for gastric and esophageal cancers is largely undefined. In this context, our study reveals several major findings. In addition to sex differences in tumor location and histology of gastric cancer, a superior relative survival was observed in male patients, despite a higher postoperative morbidity rate. In contrast, while the use of neo-adjuvant treatment differs significantly between male and female esophageal cancer patients, postoperative morbidity and 5-year relative survival were comparable.

Specifically, in female gastric cancer patients, tumors were more often located in the antrum, while in male patients, tumors were more frequently located in the gastric fundus. No sex differences were observed in tumor location for esophageal adenocarcinoma, while in the literature, a more proximal esophageal tumor location has been described in female patients [28, 29]. In line with the previous studies, we observed more poorly differentiated and diffuse-type gastric cancers in female patients [30]. As much as histologic and molecular subtypes are distributed according to a characteristic pattern within the stomach and esophagus [3133], these cancers seem to be distributed in a characteristic pattern for male and female patients, reflecting a “sexual dimorphism” most likely related to biological sex differences in cancer susceptibility and tumor biology [34].

Furthermore, significant differences in treatment allocation were observed in the current study. Even when adjusted for age, ASA-class, the presence of comorbidities, clinical stage, tumor differentiation, histopathological subtype, tumor location, and year of surgery, females with esophageal adenocarcinoma were significantly less frequently treated with neo-adjuvant therapy. No rational explanation for this treatment gap could be identified based on relevant clinicopathological factors, implicating that other factors must contribute. Potentially, unconscious gender bias in medical decisions, as described for other diseases, might play a role [3538]. In addition, female patients less often received chemotherapy with concurrent radiotherapy as neo-adjuvant regimen. This observation is consistent with the recent study of Nobel et al. [28], in which they consider prior mediastinal irradiation for breast cancer as a possible explanation for the less frequent administration of concurrent radiotherapy. Within the DUCA registry, more females had a history of malignancy; however, as type of previous cancer and mediastinal irradiation is not registered, this hypothesis could not be confirmed. Although the previous studies on chemotherapy in gastric and esophageal cancer treatment observed more toxicity in female patients, resulting in less cycles of chemotherapy [14], the current study found no difference in the percentage of patients who completed neo-adjuvant therapy.

Only for patients with gastric cancer, postoperative morbidity and re-intervention rate differed between the sexes; with more complications and more re-interventions in male patients. The higher incidence of postoperative morbidity in male patients might be explained by a higher incidence of pre-operative comorbidity and a more extensive surgical procedure, with more males undergoing a total gastrectomy in the current study [39, 40]. Of interest, the higher incidence of anastomotic leakage in male patients with gastric cancer is also frequently observed after surgery of the lower gastro-intestinal tract, with male patients at higher risk for anastomotic leakage [41, 42].

Rates of incomplete tumor removal were comparable between sexes with gastric and esophageal cancer, although higher after gastric cancer surgery. While this is in line with the literature, incomplete tumor removal negatively impacts prognosis and is associated with low annual hospital volumes, emphasizing the need for further centralization of surgical gastric cancer care [43, 44].

Since life expectancy is known to differ between male and female patients, we chose to correct this by estimating and comparing the relative survival according to the method described by Pohar Perme [23]. No significant differences in 5-year relative survival were observed between male and female patients with esophageal adenocarcinoma, portraying similar survival of both sexes with esophageal cancer allocated to surgical treatment. While this comparable survival is in line with the previous studies [28, 29], they did not take differences in life expectancy into account.

In contrast, for gastric cancer, a superior relative survival was observed in male patients. Considering the prognostic favorable lower rate of comorbidities and postoperative morbidity [21], as well as the lower pathological T stages and more distal tumor locations observed in female patients [45, 46], the inferior survival of female gastric cancer patients might be explained by differences in tumor biology, such as the higher rate of poorly differentiated and diffuse-type tumors in females, which counterbalances the favorable impact of lower comorbidities, postoperative morbidity, pathological T stage, and tumor location. This observation is consistent with others; both Dutch [47] and Norwegian [48] population-based studies demonstrated higher proportions of diffuse-type gastric cancer in female patients and a significantly poorer survival for diffuse-type cancer. Furthermore, this observation does not seem to be limited to Caucasians; a large retrospective Korean study [30] confirms the higher rate of undifferentiated and diffuse-type gastric tumors in female patients and their negative prognostic impact.

Moreover, sex differences are potentially modulated by age [38] and might be the result of differences in exposure to sex hormones [6, 24, 25]. In the current study, especially young female gastric cancer patients were diagnosed with poor tumor differentiation and diffuse-type tumors, and showed inferior relative survival compared to males, which is consistent with the literature [30, 49]. Although a protective effect of female (pre-menopausal) sex hormones is hypothesized, the current study observed more female gastric cancer patients aged ≤ 55 years, with more prognostic negative tumor characteristics and a poorer relative survival. As a consequence of the observed sex differences in tumor biology and prognosis, sex-specific multimodal treatment strategies merit consideration and investigation in clinical trials.

There were some limitations to the present study. Although the validation of the matched DUCA-Vektis dataset was not published until November 2019 [21], the matching was already performed in September 2017. Since no additional update was performed, more recent data could not be included in this study. Another limitation to this combined dataset is the error margin up to 6%, caused by the incorrect assumption of death when health care insurance was terminated, e.g., in case of emigration [21]. However, there is no reason to assume that this error affected male and female patients differently and subsequently affected the results of our study. Due to the purpose of this registry, we were not able to include patients allocated to non-surgical treatment strategies, such as definitive chemoradiotherapy. Therefore, we cannot exclude that the observed differences might be due to a different allocation of male and female patients to surgical treatment. Additionally, due to the anonymous character of the DUCA dataset, we were not able to include other variables of interest, such as socio-economic status, which might affect access to care and treatment allocation, toxicity, or a possible discrepancy between treatment advised by the multidisciplinary team and actual treatment chosen.

Future research should include all patients diagnosed with gastric and esophageal cancer, regardless of treatment, to enable further investigation of sex differences in tumor characteristics, treatment allocation, and subsequent outcomes.

In conclusion, this study clearly demonstrates statistically significant and clinically relevant sex differences in tumor characteristics, treatment allocation, postoperative morbidity, and survival among surgically treated patients with gastric and esophageal cancer. As such, it provides an illustrative example of how sex and gender modulate surgical risks and outcomes. While the observed differences in gastric cancer histology are most likely related to biological sex differences in cancer susceptibility and tumor biology, also referred to as “sexual dimorphism” in cancer, differences in patient or tumor characteristics do not explain the observed treatment gap between male and female patients with esophageal adenocarcinoma, which might be attributable to other factors, such as unconscious gender bias. Consequently, the consideration of sex and gender differences in surgical research and treatment decisions is necessary and considered as an important step toward the individualization of gastric and esophageal cancer treatment.

Supplementary Information

Below is the link to the electronic supplementary material.

Acknowledgements

The authors would like to thank all surgeons, registrars, physician assistants, and administrative nurses for data registration in the DUCA database, as well as the Dutch Upper GI Cancer Audit group for scientific input.

Funding

No funding was received for this study.

Declarations

Conflict of interest

Wagner has received consulting fees from BMS, Servier Suisse, Merck, MSD, Bayer, EMD Serono, Lilly, Celgene, Shire, and Pfizer, non-financial support (for congress participations) from Sanofi, Astra-Zeneca, AbbVIE, and Ipsen, and an educational grant from Roche to EORTC. Verhoeven has received unrestricted research grants from BMS and Roche. Van Laarhoven has served as a consultant for BMS, Celgene, Lilly, Merck, Nordic, and Servier, and has received unrestricted research funding from Bayer, BMS, Celgene, Lilly, Merck Serono, MSD, Nordic, Philips, Roche, and Servier. Van Berge Henegouwen reports research grants from Olympus and Stryker, in addition to consulting fees from Medtronic, Mylan, and Johnson and Johnson. Lemmens has received unrestricted research grants and educational grants from Roche. The remaining authors have no conflict of interest to report.

Footnotes

Publisher's Note

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Contributor Information

Marianne C. Kalff, Email: m.c.kalff@amsterdamumc.nl

Mark I. van Berge Henegouwen, Email: m.i.vanbergehenegouwen@amsterdamumc.nl

References

  • 1.Arnold M, Soerjomataram I, Ferlay J, Forman D. Global incidence of oesophageal cancer by histological subtype in 2012. Gut. 2015;64(3):381–387. doi: 10.1136/gutjnl-2014-308124. [DOI] [PubMed] [Google Scholar]
  • 2.Khazaei S, Rezaeian S, Soheylizad M, Khazaei S, Biderafsh A. Global incidence and mortality rates of stomach cancer and the human development index: an ecological study. Asian Pac J Cancer Prev. 2016;17(4):1701–1704. doi: 10.7314/apjcp.2016.17.4.1701. [DOI] [PubMed] [Google Scholar]
  • 3.Coleman HG, Xie SH, Lagergren J. The epidemiology of esophageal adenocarcinoma. Gastroenterology. 2018;154(2):390–405. doi: 10.1053/j.gastro.2017.07.046. [DOI] [PubMed] [Google Scholar]
  • 4.Freedman ND, Derakhshan MH, Abnet CC, Schatzkin A, Hollenbeck AR, McColl KEL. Male predominance of upper gastrointestinal adenocarcinoma cannot be explained by differences in tobacco smoking in men versus women. Eur J Cancer. 2010;46(13):2473–2478. doi: 10.1016/j.ejca.2010.05.005. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 5.Rutegård M, Nordenstedt H, Lu Y, Lagergren J, Lagergren P. Sex-specific exposure prevalence of established risk factors for oesophageal adenocarcinoma. Br J Cancer. 2010;103(5):735–740. doi: 10.1038/sj.bjc.6605804. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 6.Clocchiatti A, Cora E, Zhang Y, Dotto GP. Sexual dimorphism in cancer. Nat Rev Cancer. 2016;16(5):330–339. doi: 10.1038/nrc.2016.30. [DOI] [PubMed] [Google Scholar]
  • 7.Yuan Y, Liu L, Chen H, Wang Y, Xu Y, Mao H, et al. Comprehensive characterization of molecular differences in cancer between male and female patients. Cancer Cell. 2016;29(5):711–722. doi: 10.1016/j.ccell.2016.04.001. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 8.Abancens M, Bustos V, Harvey H, McBryan J, Harvey BJ. Sexual dimorphism in colon cancer. Front Oncol. 2020;10(December):1–27. doi: 10.3389/fonc.2020.607909. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 9.Li CH, Prokopec SD, Sun RX, Yousif F, Schmitz N, Al-Shahrour F, et al. Sex differences in oncogenic mutational processes. Nat Commun. 2020;11(1):1–24. doi: 10.1038/s41467-020-17359-2. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 10.Rubin JB, Lagas JS, Broestl L, Sponagel J, Rockwell N, Rhee G, et al. Sex differences in cancer mechanisms. Biol Sex Differ. 2020;11(1):1–29. doi: 10.1186/s13293-020-00291-x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 11.Van Hagen P, Hulshof MCCM, Van Lanschot JJB, Steyerberg EW, Van Berge Henegouwen MI, Wijnhoven BPL, et al. Preoperative chemoradiotherapy for esophageal or junctional cancer. N Engl J Med. 2012;366(22):2074–2084. doi: 10.1056/NEJMoa1112088. [DOI] [PubMed] [Google Scholar]
  • 12.Cunningham D, Allum W, Stenning S, Thompson J, Van de Velde C, Nicolson M, et al. Perioperative chemotherapy versus surgery alone for resectable gastroesophageal cancer. N Engl J Med. 2006;355(1):11–20. doi: 10.1056/NEJMoa055531. [DOI] [PubMed] [Google Scholar]
  • 13.Özdemir BC, Csajka C, Dotto GP, Wagner AD. Sex differences in efficacy and toxicity of systemic treatments: an undervalued issue in the era of precision oncology. J Clin Oncol. 2018;36(26):2680–2683. doi: 10.1200/JCO.2018.78.3290. [DOI] [PubMed] [Google Scholar]
  • 14.Davidson M, Wagner AD, Kouvelakis K, Nanji H, Starling N, Chau I, et al. Influence of sex on chemotherapy efficacy and toxicity in oesophagogastric cancer: a pooled analysis of four randomised trials. Eur J Cancer. 2019;121:40–47. doi: 10.1016/j.ejca.2019.08.010. [DOI] [PubMed] [Google Scholar]
  • 15.Van Putten M, Verhoeven RHA, Van Sandick JW, Plukker JTM, Lemmens VEPP, Wijnhoven BPL, et al. Hospital of diagnosis and probability of having surgical treatment for resectable gastric cancer. Br J Surg. 2016;103(3):233–241. doi: 10.1002/bjs.10054. [DOI] [PubMed] [Google Scholar]
  • 16.Van Putten M, Koëter M, Van Laarhoven HWM, Lemmens VEPP, Siersema PD, Hulshof MCCM, et al. Hospital of diagnosis influences the probability of receiving curative treatment for esophageal cancer. Ann Surg. 2018;267(2):303–310. doi: 10.1097/SLA.0000000000002063. [DOI] [PubMed] [Google Scholar]
  • 17.Songun I, Putter H, Kranenbarg EMK, Sasako M, van de Velde CJH. Surgical treatment of gastric cancer: 15-year follow-up results of the randomised nationwide Dutch D1D2 trial. Lancet Oncol. 2010;11(5):439–449. doi: 10.1016/S1470-2045(10)70070-X. [DOI] [PubMed] [Google Scholar]
  • 18.Shapiro J, van Lanschot JJB, Hulshof MCCM, van Hagen P, van Berge Henegouwen MI, Wijnhoven BPL, et al. Neoadjuvant chemoradiotherapy plus surgery versus surgery alone for oesophageal or junctional cancer (CROSS): long-term results of a randomised controlled trial. Lancet Oncol. 2015;16(9):1090–1098. doi: 10.1016/S1470-2045(15)00040-6. [DOI] [PubMed] [Google Scholar]
  • 19.Busweiler LAD, Wijnhoven BPL, van Berge Henegouwen MI, Henneman D, van Grieken NCT, Wouters MWJM, et al. Early outcomes from the Dutch upper gastrointestinal cancer audit. Br J Surg. 2016;103(13):1855–1863. doi: 10.1002/bjs.10303. [DOI] [PubMed] [Google Scholar]
  • 20.van der Werf LR, Voeten SC, van Loe CMM, Karthaus EG, Wouters MWJM, Prins HA. Data verification of nationwide clinical quality registries. BJS Open. 2019;3:857–864. doi: 10.1002/bjs5.50209. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 21.Van Der Werf LR, Wijnhoven BPL, Fransen LFC, Van Sandick JW, Nieuwenhuijzen GAP, Busweiler LAD, et al. A national cohort study evaluating the association between short-term outcomes and long-term survival after esophageal and gastric cancer surgery. Ann Surg. 2019;270(5):868. doi: 10.1097/SLA.0000000000003520. [DOI] [PubMed] [Google Scholar]
  • 22.von Elm E, Altman DG, Egger M, Pocock SJ, Gøtzsche PC, Vandenbroucke JP. The strengthening the reporting of observational studies in epidemiology (STROBE) statement: guidelines for reporting observational studies. Int J Surg. 2014;12(12):1495–1499. doi: 10.1016/j.ijsu.2014.07.013. [DOI] [PubMed] [Google Scholar]
  • 23.Perme MP, Henderson R, Stare J. An approach to estimation in relative survival regression. Biostatistics. 2009;10(1):136–146. doi: 10.1093/biostatistics/kxn021. [DOI] [PubMed] [Google Scholar]
  • 24.Camargo MC, Goto Y, Zabaleta J, Morgan DR, Correa P, Rabkin CS. Sex hormones, hormonal interventions, and gastric cancer risk: a meta-analysis. Cancer Epidemiol Biomark Prev. 2012;21(1):20–38. doi: 10.1158/1055-9965.EPI-11-0834. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 25.Lagergren K, Lagergren J, Brusselaers N. Hormone replacement therapy and oral contraceptives and risk of oesophageal adenocarcinoma: a systematic review and meta-analysis. Int J Cancer. 2014;135(9):2183–2190. doi: 10.1002/ijc.28869. [DOI] [PubMed] [Google Scholar]
  • 26.Bohanes P, Yang D, Chhibar RS, Labonte MJ, Winder T, Ning Y, et al. Influence of sex on the survival of patients with esophageal cancer. J Clin Oncol. 2012;30(18):2265–2272. doi: 10.1200/JCO.2011.38.8751. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 27.Ryu W-S, Kim J-H, Jang Y-J, Park S-S, Um J-W, Park S-H, et al. Expression of estrogen receptors in gastric cancer andtheir clinical significance. J Surg Oncol. 2012;106(4):456–461. doi: 10.1002/jso.23097. [DOI] [PubMed] [Google Scholar]
  • 28.Nobel TB, Livschitz J, Eljalby M, Janjigian YY, Bains MS, Adusumilli PS, et al. Unique considerations for females undergoing esophagectomy. Ann Surg. 2019;272(1):1. doi: 10.1097/SLA.0000000000003202. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 29.Morita M, Otsu H, Kawano H, Kasagi Y, Kimura Y, Saeki H, et al. Gender differences in prognosis after esophagectomy for esophageal cancer. Surg Today. 2014;44(3):505–512. doi: 10.1007/s00595-013-0573-x. [DOI] [PubMed] [Google Scholar]
  • 30.Kim HW, Kim JH, Lim BJ, Kim HK, Kim H, Park JJ, et al. Sex disparity in gastric cancer: female sex is a poor prognostic factor for advanced gastric cancer. Ann Surg Oncol. 2016;23(13):4344–4351. doi: 10.1245/s10434-016-5448-0. [DOI] [PubMed] [Google Scholar]
  • 31.Bass AJ, Thorsson V, Shmulevich I, Reynolds SM, Miller M, Bernard B, et al. Comprehensive molecular characterization of gastric adenocarcinoma. Nature. 2014;513(7517):202–209. doi: 10.1038/nature13480. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 32.Kim J, Bowlby R, Mungall AJ, Robertson AG, Odze RD, Cherniack AD, et al. Integrated genomic characterization of oesophageal carcinoma. Nature. 2017;541(7636):169–174. doi: 10.1038/nature20805. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 33.Rice TW, Ishwaran H, Blackstone EH. Oesophageal cancer: location, location, location. Eur J Cardio-thoracic Surg. 2015;48(2):194–195. doi: 10.1093/ejcts/ezv125. [DOI] [PubMed] [Google Scholar]
  • 34.Mauvais-Jarvis F, Bairey Merz N, Barnes PJ, Brinton RD, Carrero JJ, DeMeo DL, et al. Sex and gender: modifiers of health, disease, and medicine. Lancet. 2020;396(10250):565–582. doi: 10.1016/S0140-6736(20)31561-0. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 35.McMurray RJ, Clarke OW, Barrasso JA, Clohan DB, Epps CH, Glasson J, et al. Gender disparities in clinical decision making. JAMA J Am Med Assoc. 1991;266(4):559–562. [PubMed] [Google Scholar]
  • 36.Biddle C, Fallavollita JA, Homish GG, Orom H. Gender bias in clinical decision making emerges when patients with coronary heart disease symptoms also have psychological symptoms. Hear Lung. 2019;48(4):331–338. doi: 10.1016/j.hrtlng.2018.11.005. [DOI] [PubMed] [Google Scholar]
  • 37.Levin N, Mor M, Ben-Hur T. Patterns of misdiagnosis of multiple sclerosis. Isr Med Assoc J. 2003;5(7):489–490. [PubMed] [Google Scholar]
  • 38.Wagner AD, Oertelt-Prigione S, Adjei A, Buclin T, Cristina V, Csajka C, et al. Gender medicine and oncology: report and consensus of an ESMO workshop. Ann Oncol. 2019;30(12):1914–1924. doi: 10.1093/annonc/mdz414. [DOI] [PubMed] [Google Scholar]
  • 39.Wright CD, Kucharczuk JC, O’Brien SM, Grab JD, Allen MS. Predictors of major morbidity and mortality after esophagectomy for esophageal cancer: a society of thoracic surgeons general thoracic surgery database risk adjustment model. J Thorac Cardiovasc Surg. 2009;137(3):587–596. doi: 10.1016/j.jtcvs.2008.11.042. [DOI] [PubMed] [Google Scholar]
  • 40.Papenfuss WA, Kukar M, Oxenberg J, Attwood K, Nurkin S, Malhotra U, et al. Morbidity and mortality associated with gastrectomy for gastric cancer. Ann Surg Oncol. 2014;21(9):3008–3014. doi: 10.1245/s10434-014-3664-z. [DOI] [PubMed] [Google Scholar]
  • 41.Lipska MA, Bissett IP, Parry BR, Merrie AEH. Anastomotic leakage after lower gastrointestinal anastomosis: men are at a higher risk. ANZ J Surg. 2006;76(7):579–585. doi: 10.1111/j.1445-2197.2006.03780.x. [DOI] [PubMed] [Google Scholar]
  • 42.Rullier E, Laurent C, Garrelon JL, Michel P, Saric J, Parneix M. Risk factors for anastomotic leakage after rectal cancer surgery. Br J Surg. 1998;85(3):355–358. doi: 10.1046/j.1365-2168.1998.00615.x. [DOI] [PubMed] [Google Scholar]
  • 43.Wang SY, Yeh CN, Lee HL, Liu YY, Chao TC, Hwang TL, et al. Clinical impact of positive surgical margin status on gastric cancer patients undergoing gastrectomy. Ann Surg Oncol. 2009;16(10):2738–2743. doi: 10.1245/s10434-009-0616-0. [DOI] [PubMed] [Google Scholar]
  • 44.van der Werf LR, Cords C, Arntz I, Belt EJT, Cherepanin IM, Coene PPLO, et al. Population-based study on risk factors for tumor-positive resection margins in patients with gastric cancer. Ann Surg Oncol. 2019;26(7):2222–2233. doi: 10.1245/s10434-019-07381-0. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 45.Deng J, Chu X, Ren Z, Wang B. Relationship between T stage and survival in distantly metastatic esophageal cancer: A STROBE-compliant study. Medicine (Baltimore) 2020;99(19):e20064. doi: 10.1097/MD.0000000000020064. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 46.Yu X, Hu F, Li C, Yao Q, Zhang H, Xue Y. Clinicopathologic characteristics and prognosis of proximal and distal gastric cancer. Onco Targets Ther. 2018;11:1037–1044. doi: 10.2147/OTT.S157378. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 47.van der Kaaij RT, Koemans WJ, van Putten M, Snaebjornsson P, Luijten JCHBM, van Dieren JM, et al. A population-based study on intestinal and diffuse type adenocarcinoma of the oesophagus and stomach in the Netherlands between 1989 and 2015. Eur J Cancer. 2020;130:23–31. doi: 10.1016/j.ejca.2020.02.017. [DOI] [PubMed] [Google Scholar]
  • 48.Bringeland EA, Wasmuth HH, Mjønes P, Myklebust T, Grønbech JE. A population-based study on incidence rates, Lauren distribution, stage distribution, treatment, and long-term outcomes for gastric adenocarcinoma in Central Norway 2001–2011. Acta Oncol (Madr) 2017;56(1):39–45. doi: 10.1080/0284186X.2016.1227086. [DOI] [PubMed] [Google Scholar]
  • 49.Dijksterhuis WPM, Kalff MC, Wagner AD, Verhoeven RHA, Lemmens VEPP, van Oijen MGH, et al. Gender Differences in Treatment Allocation and Survival of Advanced Gastroesophageal Cancer: a Population-Based Study. J Natl Cancer Inst. 2021 doi: 10.1093/jnci/djab075. [DOI] [PMC free article] [PubMed] [Google Scholar]

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