Abstract
Background and study aims
Endoscopic submucosal dissection (ESD) is an optimal treatment for early gastric cancer (EGC) with negligible risk of lymph node metastasis; however, ESD is sometimes performed to treat lesions preoperatively contraindicated for the procedure due to various reasons. Here we aim to evaluate the treatment outcomes of ESD for lesions that were preoperatively contraindicated for ESD.
Patients and methods
Clinicopathological data of 104 EGC lesions in 104 patients were reviewed retrospectively. The demographic characteristics of patients, reasons for ESD, treatment results, complications, and outcomes were assessed.
Results
The major reasons for undergoing ESD included advanced age, desire to undergo ESD, and the existence of comorbidities. En-bloc and complete resection rates were 97 and 71%, respectively. Perforation and postoperative bleeding rates were 13 and 9%, respectively. Resection was beyond the expanded Japanese criteria for endoscopic treatment of EGC in 87 patients (84%), 41 (47%) of whom underwent additional therapy, including subsequent gastrectomy (29 patients) and photodynamic therapy (12 patients). The median follow-up period was 47 months, during which seven patients died from recurrent disease. The 5-year overall and disease-specific survival rates were 70 and 91.5%, respectively.
Conclusions
ESD is a technically demanding procedure for lesions preoperatively contraindicated for endoscopic resection. The curative resection rate was low, but the 5-year disease-specific survival rate of 91.5% was favourable. In experienced hands, ESD may be a treatment option for patients not suitable for radical surgery, and the relevant risk of complications must be considered before treatment.
Keywords: Early gastric cancer, endoscopic resection, endoscopic submucosal dissection, indication criteria, photodynamic therapy
Introduction
Endoscopic resection (ER) for early gastric cancer (EGC) is limited to lesions that have a negligible risk of lymph node metastasis. The Japanese Gastric Cancer Treatment Guidelines 2010 (version 3) has proposed indication criteria for EGC suitable for ER.1 Based on a negligible risk of lymph node metastasis, these criteria include lesions with a preoperative diagnosis that fulfil the conditions showed in Figure 1. With regard to technical issues, ER is recommended for EGC that can be resected en bloc depending on lesion size and location, since piecemeal resection results in a higher risk of local recurrence.2–5
Figure 1.

Criteria of early gastric cancer indicated for endoscopic resection and criteria of a curative resection.
Provided by the Japanese Gastric Cancer treatment guidelines 2010 (ver.3). ly, lymph vessel infiltration; UL, ulceration finding; v, vessel infiltration.
Endoscopic submucosal dissection (ESD) was developed to improve the en-bloc resection rate over that of endoscopic mucosal resection.2–7 Lesions that are considered impossible to remove en bloc by endoscopic mucosal resection are candidates for ESD. Therefore, it is important to decide whether a lesion should be treated by ESD taking into account of both cancer behaviour and technical issues. However, in some EGC patients, even though the lesion is preoperatively contraindicated for ER and should be treated by surgery, ER can be performed for various reasons. The aim of the present study was to investigate the present use and treatment outcomes of ECG in patients who were preoperatively contraindicated for ESD.
Methods
Patients
A total of 1576 patients with 1893 non-treated EGC lesions underwent ESD from September 2002 to December 2009 at Shizuoka Cancer Center Hospital (Shizuoka, Japan). A total of 104 patients with 104 lesions were preoperatively contraindicated for ER. Their primary physicians carefully explained the need for surgery to these patients and they received consultations from gastric surgeons. However, ESD was performed as an initial treatment for these patients. The reasons for ESD, clinicopathological characteristics, treatment results, and outcomes were retrospectively assessed.
The medical records of the 104 patients were retrospectively analysed with regard to demographics, concomitant diseases, preoperative endoscopic findings, histological findings of the ESD specimen, and additional treatment after ESD. Treatment results included the en-bloc resection rate, en bloc with complete (R0) resection rate, curative resection rate (fulfil all the conditions of curability criteria in Figure 1), and complication rate of bleeding that required haemostasis and perforation. Treatment outcomes, including local recurrence, distant metastasis, and overall survival and disease-specific survival rates were analysed.
The risks and benefits of ESD were carefully explained to every patient and written informed consent was obtained from each in accordance with our institutional protocol prior to undergoing ESD. This retrospective study was approved by the ethical committee of Shizuoka Cancer Center Hospital (approval no. 25-J12-25-1-3).
Preoperative evaluation before ESD
Before ESD, all patients were evaluated by oesophagogastroduodenoscopy with or without endosonography. A biopsy of the lesion was performed to diagnose the histological cancer type before ESD. When the lesion did not fulfil the indication criteria as shown in Figure 1, it was judged as contraindicated for ER. Before ESD, computed tomography was performed to evaluate the absence of nodal or distal metastasis.
Histological assessment of the ESD specimen
When the lesion was removed in one piece with negative margins of tumour, it was considered as en bloc with R0 resection. According to the Japanese Gastric Cancer Treatment Guidelines 2010 (version 3),1 a resection was deemed curative when all of the conditions shown in Figure 1 were fulfilled. A resection that did not satisfy any of the curative resection criteria was considered non-curative.
Statistical analysis
Survival time was calculated as the interval between the date of ESD and the date of death or the last confirmed date of being alive. Survival curves were calculated using the Kaplan–Meier method. The Cox proportional hazards model and log-rank test were used for survival analysis. All analyses were performed with Excel Statistics 2012 software (Social Survey Research Information Co, Tokyo, Japan).
Results
Demographic and tumour characteristics are summarized in Table 1. Preoperative findings that led to a contraindication for ER included lesions diagnosed as cT1a (34 lesions, 33%), among which 11 were diagnosed as differentiated type EGC >3 cm with ulcerative findings and 22 were diagnosed as undifferentiated type EGC >2 cm or with ulcerative findings. In one lesion, lymph vessel infiltration was diagnosed following biopsy. A diagnosis of cT1b was made for 70 lesions (67%). The diagnosis of cT1b in these patients was made by endoscopic findings such as clear depression with hardness or two-step elevation of the lesion during oesophagogastroduodenoscopy (Figure 2), and an additional endosonography was performed in 33 lesions. After ESD, 73% of these lesions (51/70) were diagnosed as pT1b.
Table 1.
Demographic and tumour characteristics of patients who underwent endoscopic submucosal dissection for early gastric cancer preoperatively contraindicated for endoscopic treatment
| Characteristic | Study population (n = 104) |
|---|---|
| Age (years) | 76 (46–93) |
| Sex ratio (men:women) | 79:25 |
| Concomitant disease | |
| Other cancers | 26 (25) |
| Cardiovascular disease | 51 (49) |
| Diabetes | 9 (9) |
| Chronic liver disease | 9 (9) |
| Renal failure | 2 (2) |
| Gastric cancer location | |
| Upper third | 29 (28) |
| Middle third | 47 (45) |
| Lower third | 29 (28) |
| Macroscopic type | |
| Elevated | 42 (40) |
| Depressed | 62 (60) |
| Preoperative findings that led to a contraindication for endoscopic resection | |
| cT1a | 34 (33) |
| Differentiated type with EGC >3 cm with UL | 11 |
| Undifferentiated type with EGC >2 cm or with UL | 22 |
| LY in biopsy specimen | 1 |
| cT1b | 70 (67) |
Values are median (range) or n (%).
LY, lymph vessel infiltration; UL, ulcerative findings.
Figure 2.
Chromoendoscopy pictures of 0-IIc lesions. (a) Lesion showing a well-demarcated depression, which showed hardness by deflating the air during oesophagogastroduodenoscopy, leading to a diagnosis of cT1b; the lesion was diagnosed pT1b after ESD. (b) Lesion showing a two-step elevation, with the surface being reddish and rough, leading to a diagnosis of cT1b. The lesion was diagnosed pT1b after ESD.
The reasons for performing ESD as opposed to surgery as an initial treatment are summarized in Table 2. Many patients refused surgery because of their advanced age or simply refused to undergo the procedure. In other patients, the physician’s judgment led to the selection of ESD because of concomitant disease, presence of other cancer, or gastric tube cancer.
Table 2.
Reasons for endoscopic submucosal dissection
| Reasons | Study population (n = 104) |
|---|---|
| Advanced age | 76 (73) |
| Patient’s desire | 38 (37) |
| Concomitant disease | 14 (13) |
| Presence of other cancer | 6 (6) |
| Gastric tube cancer | 3 (3) |
Values are n (%).
Numbers include overlapping cases.
Treatment results
Short-term ESD outcomes are shown in Table 3. The en-bloc resection rate was as high as 97%; however, the en bloc with R0 resection rate was 71%. Curative resection was achieved in only 17 (16%) patients. Postoperative bleeding occurred in nine (9%) patients, and four (4%) patients required blood transfusion. Sudden death occurred in one patient 3 days after ESD, which was complicated by an intraoperative perforation and postoperative bleeding. Although the perforation was successfully sealed using endoclips, and the bleeding was stopped by endoscopic haemostasis with coagulation and a blood transfusion was performed, the patient presented acute cardiac failure.
Table 3.
Short-term ESD outcomes in 104 EGC patients who were preoperatively contraindicated for the procedure
| Outcome | Study population (n = 104) |
|---|---|
| En-bloc resection | 101 (97) |
| En-bloc with complete (R0) resection | 74 (71) |
| Curative resection | 17 (16) |
| Postoperative bleeding | 9 (9) |
| Perforation | 14 (13) |
| Operation time (min) | 78 (21–420) |
Values are median (range) or n (%).
The characteristics of lesions judged as curatively resected are summarized in Table 4. Although these lesions were preoperatively contraindicated for ESD, 17 (16%) of 104 lesions were judged as curatively resected after histological assessment of the specimen. Twelve of the 17 (70%) curatively resected patients were falsely classified as EGC invading the submucosa. A preoperative diagnosis was undifferentiated type cT1a >2 cm in another three lesions, however the final diagnosis was differentiated dominant type pT1a. The other two lesions were preoperatively diagnosed as differentiated type cT1a with ulceration finding (UL) >3 cm; however, the final diagnosis was differentiated type pT1a without UL (Figure 3).
Table 4.
Characteristics of lesions that were judged as achieving curative resection after preoperative contraindication for ESD
| Preoperative diagnosis | Postoperative diagnosis | Reason for misdiagnosis |
|---|---|---|
| cT1b: 12 | pT1a: 11 | Misjudgement of depth |
| pT1b (SM1), <3 cm: 1 | ||
| Undifferentiated type cT1a with UL or >2 cm: 3 | Differentiated type, pT1a: 3 | Misjudgement of histology type |
| cT1a with UL >3 cm: 2 | pT1a without UL: 2 | Misjudgement of diagnosis of ulcerative findings |
SM1, submucosal invasion <500 µm below the muscularis mucosa; UL, ulcerative findings.
Figure 3.
Endoscopic images of lesions showing central redness and fold convergence. (a) Depressed lesion, leading to a diagnosis of 0-IIc with ulcer scar; the lesion was diagnosed as pT1a without ulceration finding after ESD. (b) An elevated lesion, leading to a diagnosis of 0-IIa with ulcer scar; the lesion was diagnosed as pT1a without ulceration finding after ESD.
Among the 87 (84%) of 104 patients with non-curative resections, 41 (47%) underwent additional treatment. Once again the need for radical surgery was carefully explained to each patient and 29 patients agreed to undergo subsequent surgery. Of these patients, 19 patients were positive of lymphovascular infiltration, seven patients had massive submucosal invasion, and the other three patients had other factors of non-curative resection. The remaining 12 patients refused surgery and received photodynamic therapy (PDT). Of the 29 patients who underwent additional surgery, 18 had neither residual cancer nor lymph node metastasis, six had residual cancer without lymph node metastasis, and five had lymph node metastasis only. Among the 18 patients with no residual cancer or lymph node metastasis, the histology was differentiated type in 15 patients: 10 had lymphovascular infiltration, six had massive submucosal invasion, and three patients had positive deep margins of the ESD specimen.
Reasons for not undergoing additional therapy in the remaining 46 patients included concomitant diseases (unfit for surgery), presence of another cancer, advanced age, and patient refusal. In five (11%) of 46 lesions, observation was chosen by the physician because the only reason for non-curative resection was an indefinite tumour margin.
Outcomes
The median follow-up period was 47 months (range 1–126 months). Local recurrence was detected in three patients and distant metastasis in six patients. A total of seven patients died from gastric cancer. The 5-year overall and disease-specific survival rates were 70% (95% CI 0.59–0.80) and 91.5% (95% CI 0.85–0.97), respectively.
The 5-year overall survival rates for patients following curative ESD, non-curative ESD with surgery, non-curative ESD with PDT, and non-curative ESD without additional treatment were 100, 72, 39, and 63%, respectively (Figure 4 and Table 5). The hazard ratios for overall survival in patients following non-curative ESD with surgery, with PDT, and without additional treatment compared with those who underwent curative ESD were 3.24, 8.56, and 8.56, respectively (Table 5). There was no significant difference between the 5-year disease-specific survival rates among patients who underwent curative ESD, non-curative ESD with surgery, and non-curative ESD without additional treatment, (100, 96, and 89%, respectively) (Figure 5). However, the 5-year disease-specific survival rate of patients who underwent non-curative ESD with PDT was significantly low as 64% (p = 0.02; Figure 5).
Figure 4.
Kaplan–Meier analysis of overall survival among patients following curative ESD and non-curative ESD with or without additional treatment.
ESD, endoscopic submucosal dissection; PDT, photodynamic surgery.
Table 5.
Hazard ratios of overall survival according to curability of ESD and additional treatment
| Treatment | No. of deaths (death from gastric cancer) | 5-year survival rate (95% CI) | HR |
|---|---|---|---|
| Curative ESD | 1 (0) | 1.00 | 1.00 |
| Non-curative ESD with surgery | 7 (1) | 0.72 (0.54–0.90) | 3.24 |
| Non-curative ESD with PDT | 5 (2) | 0.39 (0.05–0.73) | 8.56 |
| Non-curative ESD without additional treatment | 18 (4) | 0.63 (0.46–0.78) | 8.56 |
ESD, endoscopic submucosal dissection; PDT, photodynamic surgery.
Figure 5.
Kaplan–Meier analysis of disease-specific survival among patients following curative ESD and non-curative ESD with or without additional treatment.
ESD, endoscopic submucosal dissection; PDT, photodynamic surgery.
Discussion
Radical surgery is an accepted standard treatment for EGC. Patients who are preoperatively assessed with a negligible risk of lymph node metastasis are candidates of ER; additional surgery is recommended if the resection is judged as non-curative.8,9 However, surgery may not be an optimal treatment option for all EGC patients with a risk of lymph node metastasis because it carries a significant risk of morbidity and mortality.10–12
Our study showed a low complete resection rate of ESD performed for lesions preoperatively assessed as contraindicated for ESD, which was clearly lower than those for lesions indicated for ER reported in previous studies.13–15 Among previous reports regarding the feasibility of ESD for contraindicated lesions, a low complete resection rate of 55.6% (10/18) was reported for undifferentiated cancer and 36.6% (15/41) for submucosal invasive cancer.16 Regarding the depth of EGC, the technical feasibility of ESD between pT1a (M) and pT1b (SM1) lesions was reported as the same regarding the complete resection and complication rates.17 However, for pT1b (SM2) lesions (invasion of 500 µm or deeper below the muscularis mucosa), the complete resection rate was significantly low (57.8%, 48/83) compared with pT1b (SM1).18
Bleeding and perforation are major ESD complications. The complication rate for bleeding is reportedly 0–15.6, and for perforation 1.2–5.2%.19–22 In our series, the rate of postoperative bleeding and perforation reached 9 and 13%, respectively. Suzuki et al.23 also reported a disappointing postoperative bleeding rate of 18.4% (7/38) and a perforation rate of 13.2% (5/38) among operable patients with cT1b EGC who refused surgery and underwent ESD. Regrettably, these data are insufficient to assess the technical validity of ESD for lesions preoperatively contraindicated for ER in terms of both complete resection rate and complication risk. In particular, the present ER indication criteria that were determined by a negligible risk of lymph node metastasis could also be interpreted as indices of lesions technically amenable to safe and reliable ESD.
Our data showed a 5-year disease-specific survival rate of 91.5% for patients who underwent ESD for lesions preoperatively contraindicated for ER. Similar results were shown in operable patients with cT1b EGC who underwent ESD as an initial treatment with a 5-year disease-specific survival rate of 91.8%.23 Other studies reported similar 5-year disease-specific rates among patients who underwent non-curative ESD with or without surgery.9,18 In patients older than 75 years, additional surgery is recommended following non-curative ER.24 Our study population mostly included patients with some reason to hesitate undergoing radical surgery as an initial treatment. Therefore, it is difficult to compare survival rates between patients who underwent non-curative ESD with additional surgery and those who did not undergo additional surgery due to poor physical condition. In fact, in our study, 23 of 29 patients who did not receive surgery after non-curative ESD died of other causes during the follow-up period.
Our study included 12 patients who underwent PDT after non-curative ESD but did not undergo surgery due to physical condition or refusal. The resected lesions were either pT1b with or without positive resection margins. PDT was employed to eliminate any local residual cancer cells after ESD. At present, PDT is considered as a palliative treatment for EGC patients who are contraindicated for curative endoscopic treatment or surgery.25 The overall survival rate of patients who received PDT after non-curative ESD was low in our study; thus, it was difficult to determine the additional effect of PDT. Moreover, individual factors, such as comorbidities and reasons for non-curative ESD, ultimately influenced whether to administer additional treatment after ESD, thereby resulting in a possible selection bias.
In conclusion, ESD is a technically demanding procedure for lesions preoperatively assessed as contraindicated for ER. The curative resection rate was low and did not seem to play an important prognostic role. However, the 5-year disease-specific survival rate was favourable. In experienced hands, ESD may be a treatment option for patients not suitable for radical surgery and the relevant risk of complications must be considered before treatment.
Funding
This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Conflict of interest
The authors declare that there is no conflict of interest.
Presentation
This study was presented at the 20th United European Gastroenterology Week held in Amsterdam, The Netherlands, 2012.
References
- 1.Japanese Gastric Cancer Association. Japanese gastric cancer treatment guideline 2010 (ver3). Gastric Cancer 2011; 14: 113–12321573742 [Google Scholar]
- 2.Oka S, Tanaka S, Kaneko I, et al. Advantage of endoscopic submucosal dissection compared with EMR for early gastric cancer. Gastrointest Endosc 2006; 64: 877–883 [DOI] [PubMed] [Google Scholar]
- 3.Kakushima N, Fujishiro M. Endoscopic submucosal dissection for gastrointestinal neoplasms. World J Gastroenterol 2008; 14: 2962–2967 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Cao Y, Liao C, Tan A, et al. Meta-analysis of endoscopic submucosal dissection versus endoscopic mucosal resection for tumors of the gastrointestinal tract. Endoscopy 2009; 41: 757–757 [DOI] [PubMed] [Google Scholar]
- 5.Park YM, Cho E, Kang HY, et al. The effectiveness and safety of endoscopic submucosal dissection compared with endoscopic mucosal resection for early gastric cancer: a systematic review and metaanalysis. Surg Endosc 2011; 25: 2666–2677 [DOI] [PubMed] [Google Scholar]
- 6.Lian J, Chen S, Zhang Y, et al. A meta-analysis of endoscopic submucosal dissection and EMR for early gastric cancer. Gastrointest Endosc 2012; 76: 763–770 [DOI] [PubMed] [Google Scholar]
- 7.Ono H, Kondo H, Gotoda T, et al. Endoscopic mucosal resection for treatment of early gastric cancer. Gut 2001; 48: 225–229 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Goto O, Fujishiro M, Kakushima N, et al. Endoscopic submucosal dissection as a staging measure may not lead to worse prognosis in early gastric cancer patients with additional gastrectomy. Dig Liver Dis 2008; 40: 293–297 [DOI] [PubMed] [Google Scholar]
- 9.Oda I, Gotoda T, Sasako M, et al. Treatment strategy after non-curative endoscopic resection of early gastric cancer. Br J Surg 2008; 95: 1495–1500 [DOI] [PubMed] [Google Scholar]
- 10.Sasako M. Risk factors for surgical treatment in the Dutch Gastric Cancer Trial. Br J Surg 1997; 84: 1567–1571 [DOI] [PubMed] [Google Scholar]
- 11.Bonenkamp JJ, Songun I, Hermans J, et al. Randomized comparison of morbidity after D1 and D2 dissection for gastric cancer in 996 Dutch patients. Lancet 1995; 345: 745–748 [DOI] [PubMed] [Google Scholar]
- 12.Bonenkamp JJ, Hermans J, Sasako M, et al. Extended lymph-node dissection for gastric cancer. N Engl J Med 1999; 340: 908–914 [DOI] [PubMed] [Google Scholar]
- 13.Ono H, Hasuike N, Inui T, et al. Usefulness of a novel electrosurgical knife, the insulation-tipped diathermic knife-2, for endoscopic submucosal dissection of early gastric cancer. Gastric Cancer 2008; 11: 47–52 [DOI] [PubMed] [Google Scholar]
- 14.Goto O, Fujishiro M, Kodashima S, et al. Outcomes of endoscopic submucosal dissection for early gastric cancer with special reference to validation for curability criteria. Endoscopy 2009; 41: 118–122 [DOI] [PubMed] [Google Scholar]
- 15.Nishide N, Ono H, Kakushima N, et al. Clinical outcomes of endoscopic submucosal dissection for early gastric cancer in remnant stomach or gastric tube. Endoscopy 2012; 44: 577–583 [DOI] [PubMed] [Google Scholar]
- 16.Goh P, Jeong H, Kim M, et al. Clinical outcomes of endoscopic submucosal dissection for undifferentiated or submucosal invasive early gastric cancer. Clin Endosc 2011; 44: 116–122 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 17.Hoteya S, Yamashita S, Kikuchi D, et al. Endoscopic submucosal dissection for submucosal invasive gastric cancer and curability criteria. Digestive Endosc 2011; 23: 30–36 [DOI] [PubMed] [Google Scholar]
- 18.Sanomura Y, Oka S, Tanaka S, et al. Clinical validity of endoscopic submucosal dissection for submucosal invasive gastric cancer: a single-center study. Gastric Cancer 2012; 15: 97–105 [DOI] [PubMed] [Google Scholar]
- 19.Takizawa K, Oda I, Gotoda T, et al. Routine coagulation of visible vessels may prevent delayed bleeding after endoscopic submucosal dissection – an analysis of risk factors. Endoscopy 2008; 40: 179–183 [DOI] [PubMed] [Google Scholar]
- 20.Miyahara K, Iwakiri R, Shimoda R, et al. Perforation and postoperative bleeding of endoscopic submucosal dissection in gastric tumors: analysis of 1190 lesions in low- and high-volume centers in Saga, Japan. Digestion 2012; 86: 273–280 [DOI] [PubMed] [Google Scholar]
- 21.Kim S, Moon J, Youn Y, et al. Management of the complications of endoscopic submucosal dissection. World J Gastroenterol 2011; 17: 3575–3579 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 22.Oda I, Suzuki H, Nonaka S, et al. Complications of gastric endoscopic submucosal dissection. Digestive Endosc 2013; 25: 71–78 [DOI] [PubMed] [Google Scholar]
- 23.Suzuki H, Oda I, Nonaka S, et al. Is endoscopic submucosal dissection an effective treatment for operable patients with clinical submucosal invasive early gastric cancer? Endoscopy 2013; 45: 93–97 [DOI] [PubMed] [Google Scholar]
- 24.Kusano C, Iwasaki M, Kaltenbach T, et al. Should elderly patients undergo additional surgery after non-curative endoscopic resection for early gastric cancer? Long-term comparative outcomes. Am J Gastroenterol 2011; 106: 1064–1069 [DOI] [PubMed] [Google Scholar]
- 25.Nakamura H, Yanai H, Nishikawa J, et al. Experience with photodynamic therapy (endoscopic lase therapy) for treatment of early gastric cancer. Hepatogastroenterology 2001; 48: 1599–1603 [PubMed] [Google Scholar]




