Laparoscopic colorectal surgery appears to be feasible and safe in elderly patients with increased comorbidity.
Keywords: Laparoscopic surgery, Colorectal cancer, Elderly patients
Abstract
Objective:
To evaluate the short-term outcomes of laparoscopic colorectal surgery for cancer in the elderly compared with younger patients.
Methods:
We retrospectively considered a consecutive unselected series of 159 patients who underwent elective laparoscopic procedures for colorectal cancer at our institution between January 2007 and December 2009. Of these patients, 101 (63.5%) were ≤70 years of age (Group A), and 58 (36.5%) were >70 (Group B). Operative steps and instrumentation were standardized. Demographics, disease-related, operative, and short-term data were analyzed for each group, and an appropriate statistical comparison was made. Comorbidity was quantified by using the Charlson Comorbidity Index.
Results:
We reviewed right colectomies (29.5%), left colectomies (44.7%), rectal resections (19.5%), and other procedures (6.3%). There was no significant difference in sex ratio, body mass index, American Society of Anesthesiology score, type of surgical procedures, and tumor stage between Group A and Group B. A statistically higher comorbidity according to the Charlson index characterized Group B (2.2 vs 3.8; P=.034). Median operative time (228±78.1min vs 224.3±97.6min; NS), estimated blood loss (50.0±94.8mL vs 31.2±72.7mL; NS), conversion rate (2.0% vs 1.7%; NS), and timing to canalization (4.5±1.7dd vs 4.4±1.3dd; NS) were statistically comparable in both Groups. Group B was associated with a significantly longer length of hospital stay compared with Group A (8.1±2.8dd vs 10.8±6.6dd; P<.01) There was no statistically significant difference in major postoperative complications (3.8% vs 3.4%; NS), reoperations (0.9% vs 1.7%; NS), and 30-day mortality (0% vs 1.7%; NS).
Conclusions:
Laparoscopic colorectal surgery appears feasible and safe in elderly patients with increased comorbidity.
INTRODUCTION
The constant improvements in healthcare and technology have increased life expectancy, particularly in Western countries. Globally, the World Health Organization reports that 2 billion people (23% of the population worldwide) will be older than 60 in the year 2050. In Italy, the last National Institute of Statistics (ISTAT) census in 2001 estimated that 18% of the country's population was over 65 years of age. Colorectal cancer (CRC) is a major cause of morbidity and mortality in the elderly, because >70% of cases occur in people over 65 years of age.1
It is felt that, because of an aging population, surgeons will be operating on an increasing amount of CRC in elderly patients. Compared to conventional procedures, laparoscopic colorectal surgery (LCS) is associated with less postoperative pain, better pulmonary function, reduced ileus, and a shorter hospital stay.2–3 Moreover, randomized clinical trials and a metaanalysis have recognized that the long-term oncologic outcome of LCS procedures is at least comparable to that of open surgery (OS).4–5
This study aims to evaluate the short-term outcomes of LCS for CRC in elderly patients, assuming that there are no statistically significant differences compared with younger patients.
METHODS
We retrospectively considered a consecutive unselected series of 159 patients who underwent elective LCS for CRC at our institution between January 2007 and December 2009. Of these patients, 101 (63.5%) were ≤70 years of age (Group A), and 58 (36.5%) were >70 (Group B).
Patients with open procedures, surgery for benign diseases, and emergency operations were excluded from this study. Exclusion criteria for LCS were only the denial of consent by the patient and the cases of bowel obstruction not treatable by colonic stent as a bridge to LCS. In patients with a history of extensive adhesions, we decided to continue the operation by laparoscopy or convert it to conventional surgery only after an exploratory laparoscopy.
We considered right colectomies, left colectomies, and rectal resections. Patients in the group “Others” underwent laparoscopic transverse resections and Miles procedures.
Data on demographics of patients, disease features, operative details, and follow-up were extracted from a prospectively collected database, and further clinical information was obtained by the review of clinical papers. Comorbidity was weighted using the Charlson comorbidity index (CCI).
Preoperative care was standardized. All patients followed a low-fiber diet with a high-caloric intake during the 5 days prior to surgery, and no bowel preparation was performed. A nasogastric tube and a urinary catheter were placed after induction of general anesthesia in all cases.
All patients were treated with broad-spectrum intravenous antibiotics (Ceftizoxime + Metronidazole).
All procedures were performed or supervised by the same surgeon (IS). Operative steps and surgical instruments were completely standardized. All were 4-port laparoscopic procedures. Dissection was performed using a Harmonic scalpel, vascular trunks were ligated using Endoclips or stapled by a white-load linear laparoscopic device.
Regarding laparoscopic right colectomies, we performed medial-to-lateral operations both with extracorporeal and intracorporeal ileocolic anastomosis, because, in our learning curve, we have previously performed this procedure with laparoscopic assistance. For the last 3 years a totally laparoscopic technique has been routine. In laparoscopic left colectomies and rectal resections, we performed a conventional medial-to-lateral approach with a Knight-Griffen mechanical end-to-end anastomosis. For rectal cancers, a total mesorectal excision (TME) was always performed. Mid and low rectal anastomoses were made nonfunctional with a loop ileostomy. Drains were not used routinely.
Postoperative care was standardized. All patients were mobilized early, with removal of the urinary catheter. Nasogastric tube was removed after the first flatus, and then the patient began oral intake. Criteria for the discharge included the absence of symptoms, tolerance to a minimum of 3 meals without restrictions and passage of stool.
Clinical follow-up was performed on the 5th and 30th days after hospital discharge.
Continuous variables are expressed as mean ± standard deviation and were analyzed with the Student t test, while categorical ones are expressed as percentage value and were analyzed with Fischer's test or chi-square test, when appropriate. P<.05 was considered statistically significant. SPSS v. 18.0.0 (SPSS Inc., Chicago, IL, USA) was used for the analysis.
RESULTS
We analyzed right colectomies (29.5%), left colectomies (44.7%), rectal resections (19.5%), and other procedures (6.3%). Demographics and disease-related data are summarized in Table 1.
Table 1.
Group A (≤70yo) |
Group B (>70yo) |
P Value | |
---|---|---|---|
n = 101 (%) | n = 58 (%) | ||
Age | 60.4 ±6.6 | 77.1 ±4.5 | |
Male/Female | 60/ 41 (59.4/40.6) | 26/ 32 (44.8/55.2) | .075 |
BMIa | 26.2 ±3.9 | 24.8 ±3.5 | .231 |
ASA Scoreb | |||
I | 20 (19.8) | 9 (15.5) | .500 |
II | 77 (76.2) | 40 (69.0) | .316 |
II | 4 (4.0) | 7 (12.1) | .052 |
IV | 0 (0) | 2 (3.4) | .060 |
Comorbidity CCIc | 2.2 | 3.8 | .034 |
Surgical Procedures | |||
Right colectomy | 29 (28.7) | 18 (31.0) | .757 |
Left colectomy | 44 (43.6) | 27 (46.5) | .715 |
Rectal resection | 21 (20.8) | 10 (17.4) | .586 |
Othersd | 7 (6.9) | 3 (5.1) | .660 |
BMI=Body mass index.
ASA=American Society of Anesthesiology.
CCI=Charlson Comorbidity Index.
Laparoscopic transverse resections and laparoscopic Miles procedure.
There was no significant difference in sex ratio, body mass, and ASA score between Group A and Group B. Type of surgical procedures was also similar.
Evaluation of specimens is outlined in Table 2. There were no significant differences between the 2 groups in the number of lymph nodes harvested and in the histopathologic findings, although Group A had a significantly greater number of patients in stage IV of the disease.
Table 2.
Group A (≤70 y) |
Group B (>70 y) |
P Value | |
---|---|---|---|
n = 101 | n = 58 | ||
Operative Time (min) | 228 ± 78.1 | 224.3 ± 97.6 | 0.793 |
Estimated Blood Loss (mL) | 50,0 ± 94.8 | 31.2 ± 72.7 | 0.193 |
Timing of First Stool (d) | 4,5 ± 1.7 | 4.4 ± 1.3 | 0.699 |
Hospital stay (d) | 8,1 ± 2.8 | 10.8 ± 6.6 | <0.01 |
Conversions | 2 (2.0%) | 1 (1.7) | 0.909 |
Anastomotic Leakage | 3 (2.9%) | 1 (1.7%) | 0.629 |
Other Major Complications | 1 (0.9%) | 1 (1.7%) | 0.689 |
Reoperations | 1 (0%) | 1 (1.7%) | 0.689 |
30-Days Mortality | 0 (0%) | 1 (1.7%) | 0.185 |
Group B was associated with a statistically higher comorbidity according to CCI (2.2 vs 3.8; P=.034). Table 3 shows data related to operations and short-term outcome.
Table 3.
Group A (≤70yr) |
Group B (>70yr) |
P Value | |
---|---|---|---|
n = 101 (%) | n = 58 (%) | ||
Operative time (min) | 228 ±78.1 | 224.3 ±97.6 | .793 |
Estimated blood loss (mL) | 50.0 ±94.8 | 31.2 ±72.7 | .193 |
Timing of first stool (dd) | 4.5 ±1.7 | 4.4 ±1.3 | .699 |
Hospital stay (dd) | 8.1 ±2.8 | 10.8 ±6.6 | <.01 |
Conversions | 2 (2.0) | 1 (1.7) | .909 |
Anastomotic leakage | 3 (2.9) | 1 (1.7) | .629 |
Other major complications | 1 (0.9) | 1 (1.7) | .689 |
Reoperations | 1 (0) | 1 (1.7) | .689 |
30-day mortality | 0 (0) | 1 (1.7) | .185 |
Median operative time (228±78.1min vs 224.3±97.6min; NS), estimated blood loss (50.0±94.8mL vs 31.2±72.7mL; NS), conversion rate (2.0% vs 1.7%; NS), and timing of first defecation (4.5±1.7 dd vs 4.4±1.3dd; NS) were statistically comparable in both Groups.
A significantly longer length of hospital stay characterized Group B compared with Group A (8.1±2.8dd vs 10.8±6.6dd; P<.01).
There was no statistically significant difference in terms of major postoperative complications (3.8% vs 3.4%; NS), reoperations (0.9% vs 1.7%; NS), and 30-day mortality (0% vs 1.7%; NS).
DISCUSSION
Since the first report by Jacobs in 1991,6 improvements in technology and standardization of techniques have contributed to diffusion of LCS, and a lot of studies have been published about this topic. Nowadays, short-term benefits of LCS compared to OS are well known and include less pain, better pulmonary function, shorter postoperative ileus and hospital stay.2–5 In addition, recent randomized clinical trials and a meta-analysis show, with level 1 evidence, that LCS achieves good oncological results compared to OS.6–10
This study was designed to determine whether these advantages could also be applied to the elderly, starting from the consideration that the increased life expectancy in western countries will lead us to a growing number of colorectal resections in patients over 70 years of age.
We have set the cut off age of 70 years as the threshold conventionally chosen by the scientific community to define old age, and it is also the master indicator most widely used.
We believe that patients, such as the elderly, who have more comorbidities could benefit from better postoperative inflammatory response that characterizes LCS. However, data from the current literature are contradictory and unclear about the real risks or benefits of LCS in the elderly.
Two large studies7,8 including 1421 and 1316 patients, respectively, were conducted to identify predictive risk factors for intra- and postoperative complications following LCS procedures. Both studies stated that patient age, over 70 for the Association Française de Chirurgie Study Group,12 over 75 for Kirchhoff et al,13 independently increased the risk of postoperative complications. Nevertheless, the largest comparative study of LCS in the elderly by Tan et al9 concluded that age was not an independent predictor of morbidity and mortality of LCS for CRC.
As can be seen in Table 4, some authors compared LCS in older patients with OS, and substantially all of them suggested the great benefit of minimally invasive procedures.10–22 Only a few comparative studies have compared the outcomes of LCS in the elderly with that in younger patients. However, in the study by Schwandner et al,11 types of LCS procedures were not comparable between elderly and younger cohorts, while Reissman and colleagues12 used a cut-off of 60 years old, which is too early in our view. Finally, Yamamoto et al13 compared 34 patients ≤60 of age to only 17 octogenarians, and the number of laparoscopic rectal resections was quite small.
Table 4.
Year | Operationa | n | Age | Conversion rate (%) | Hospital stay (dd) | Morbidity (%) | Mortality (%) | |
---|---|---|---|---|---|---|---|---|
Reissman24 | 1996 | LCS | 36 | <60 | 8 | 5.2 | 11 | 0 |
LCS | 36 | >60 | 11 | 6.5 | 14 | 0 | ||
Schwandner23 | 1999 | LCS | 65 | <50 | 3.1 | 11.5 | 4.6 | |
LCS | 138 | 50-70 | 9.4 | 13.3 | 10.1 | |||
LCS | 95 | >70 | 7.4 | 17.2 | 9.5 | |||
Stewart15 | 1999 | LCS | 42 | >80 | 11.9 | 9 | 16.6 | 7.1 |
OCS | 35 | >80 | 17 | 42.8 | 11.4 | |||
Delgado16 | 2000 | LCS | 70 | <70 | 11.4 | 5 ±2 | 11.4 | 0 |
OCS | 59 | <70 | 7 ±3 | 20.3 | 0 | |||
LCS | 59 | >70 | 16.9 | 6 ±2 | 10.01 | 1.6 | ||
OCS | 67 | >70 | 7 ±3 | 31.3 | 0 | |||
Tuech17 | 2000 | LCS | 22 | >75 | 9 | 13.1 | 18 | 0 |
OCS | 24 | >75 | 20.2 | 50 | 0 | |||
Stocchi18 | 2000 | LCS | 42 | >75 | 14.3 | 6.5 | 14.3 | 0 |
OCS | 42 | >75 | 10.2 | 33.3 | 0 | |||
Law19 | 2002 | LCS | 65 | >70 | 12.3 | 7 | 27.7 | 1.5 |
OCS | 89 | >70 | 9 | 37 | 5.6 | |||
Senagore20 | 2003 | LCS | 181 | <60 | 3.9 ±5.9 | 10.5 | 0 | |
OCS | 122 | <60 | 6.1 ±3.0 | 13.1 | 0 | |||
LCS | 50 | >70 | 4.2 ±3.0 | 16 | 0 | |||
OCS | 123 | >70 | 9.3 ±7.6 | 37.4 | 1.6 | |||
Sklow22 | 2003 | LCS | 38 | <75 | 16 | 6.7 | 29 | 0 |
OCS | 38 | <75 | 7.7 | 37 | 0 | |||
LCS | 39 | >75 | 8 | 3.9 | 31 | 2.6 | ||
OCS | 39 | >75 | 4.9 | 31 | 0 | |||
Yamamoto25 | 2003 | LCS | 34 | <60 | 0 | 9 | 23.5 | 0 |
LCS | 17 | >80 | 0 | 10 | 11.7 | 0 | ||
Feng21 | 2006 | LCS | 51 | >70 | 3.9 | 17.6 | 0 | |
OCS | 102 | >70 | 37.3 | 1.9 | ||||
Chautard J 26 | 2008 | LCS | 103 | <70 | 16 | 10 ±9 | 27 | 0 |
LCS | 75 | >70 | 21 | 11 ±8 | 32 | 0 | ||
Tan KY 14 | 2010 | LCS | 379 | <70 | 8 | 13 | 0.3 | |
LCS | 91 | >75 | 7 | 15 | 3 |
LCS = Laparoscopic Colorectal Surgery; OCS = Open Colorectal Surgery.
Only the article from Chautard et al14 has not shown biases in patient recruitment and selection, observing a large series of LCS procedures with a high percentage of rectal resections (34% of overall) and obtaining similar postoperative outcomes in patients over 70 compared with younger ones.
Here, our 2 series of patients were homogeneous in terms of tumor stage and type of surgery, with a statistically proper percentage of rectal resections. In addition, the homogeneity of our groups was confirmed by the fact that a single surgeon performed, or supervised, or both, all procedures.
Predictably, older patients showed a significantly higher incidence of comorbidity according to CCI. The Charlson Comorbidity Index is a method with 22 variables, such as heart diseases, diabetes, AIDS, or previous cancer, to measure comorbidity. Despite the fact that its use was not originally by surgeons,15 in our opinion CCI represents a good index to weigh comorbid conditions of patients and to predict postoperative complications. In fact, the surgical risk is directly correlated to the number of comorbidities of a patient. Remember that a CCI >3 is associated with a 1-year mortality, twice that of a score of <3. So the indexes of our 2 groups express properly the risk of postoperative complications, emerging statistically higher in the elderly. But we have not recorded significant differences in terms of ASA score, which is typically a pattern of preoperative evaluation.
Although we registered different comorbidity scores, there were no significant differences in term of operative time, blood loss, and conversion rate between our 2 study groups, and this underlines the fact that we have not encountered major technical difficulties in laparoscopic procedures in older patients. There was also a sort of scepticism about LCS in elderly patients, due to the potential adverse hemodynamic effects both by the prolonged pneumoperitoneum and the extreme positions of patients during the laparoscopic operations, but we did not encounter any anesthesiological problems related to circulation during the procedures.
Laparoscopic surgery is associated with less surgical trauma and therefore with a lower systemic response to surgical stress.16 This aspect provides advantages to patients at high risk, such as the elderly, improving postoperative outcomes and providing good results, comparable to outcomes in younger patients.
In our experience, the low rate of anastomotic leakage and other postoperative complications, reoperations, and 30-day mortality suggests that LCS should be the preferred choice for elderly persons undergoing colorectal surgery. Only the length of hospital stay was significantly higher in our over 70 group, although the postoperative management of patients has been completely standardized according to the procedure. This is explained both by increased caution in the discharge of the elderly and, sometimes, our intention to meet the needs of these patients and their families.
CONCLUSION
LCS appears feasible and safe in elderly patients with increased comorbidity. In our experience, aging did not bring about a significant worsening of intra- and postoperative outcomes after laparoscopic colorectal procedures.
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