This is a retrospective study analyzing laparoscopic radical surgery for elderly CRC patients with a largest case number from a single academic medical center. The results presented the real-world experience in a single institute to strengthen the laparoscopic procedure for elderly patients with CRC. In our study, although elderly patients with CRC who underwent laparoscopy were prone to develop early T stage cancer, obesity and high serum albumin level, their length of postoperative stay was significantly shorter, their postoperative morbidity and mortality were similar to that of those underwent open surgery, and the rate of conversion was acceptably low (6 out of 305 patients, and 1 died). In each TNM stage, the long-term outcomes including OS rate, CSS rate and CRR between the open surgery group and the laparoscopy group were also similar.
For elderly patients with non-metastatic CRC who underwent surgery, we revealed that the overall postoperative morbidity and mortality rates were similar in the open group and the laparoscopy group. The postoperative morbidity rate was 15.4% and the mortality rate was 0.3% in the laparoscopy group. The operative mortality and morbidity of laparoscopy were similar and even lower than some reports [16-21], and the results represented the real-world condition about short-term outcome in Taiwan. The role of laparoscopic surgery in colorectal cancer treatment is worldwide accepted[8, 22]. However, considering the surgical risks in elderly patients (high risks of anesthesia, operative morbidity and mortality, malnutrition, immunity decline, poor performance status, and having comorbidities)  and long operation time, surgeons may hesitate to perform laparoscopic surgery on elderly patients. Seshadri et al. reported that 62 octogenarians who received laparoscopic colorectal procedure (including benign disease) in the 1990s resulted in favorable postoperative outcome . Law et al. compared the groups of open and laparoscopic colorectal resections of malignant or benign colorectal disease in Asians aged over 70 years in early 2000, and the two groups shared similar postoperative morbidity rates . Fujii et al. had reported that the postoperative complication rate in the laparoscopy group was lower than that in the open group (23% vs. 36%) for elderly patients, and the postoperative ileus rate in the laparoscopy group was significantly lower .
The conversion rate was 2% in our study and it was similar to or even lower than previous studies (6.1%-21%) [13, 16, 26-29]. Of these converted patients, only three patients developed postoperative morbidity and none had tumor recurrence during follow-up. The short-term or long-term outcomes may not be influenced by the conversion if adequate surgical safety is achieved. The retrieved lymph nodes in the two groups were sufficient as suggestions for the guidelines. We agreed that laparoscopic surgery could meet the similar oncological quality as open surgery for CRC treatment through this study. The length of postoperative stay was shorter in the laparoscopic group, and several studies had confirmed the result [16, 18, 25, 28, 30-32]. The most obvious benefit for elderly patients to receive laparoscopy surgery is a reduction in hospital stay.
To our knowledge, there were few studies focusing on the long-term oncological outcomes in elderly patients receiving open surgery and laparoscopy surgery, and this study is the largest cohort from a single medical center to analyzing laparoscopic surgery for the elderly with colorectal cancer. The long-term oncological outcomes including OS, CSS and CRR did not differ between the two groups. In our study, patients in the open group had much advanced TNM stage and abnormal CEA level compared to the laparoscopy group. This finding may be due to the surgeons’ preference for patient selection. However, we divided the patients into 3 groups by TNM stage, and the long-term oncological outcomes showed no difference in each group. Several studies had reported that OS and disease-free survival did not differ between patients undergoing open surgery and laparoscopy [14, 31-33].
This study reports cancer-specific survival and cumulative recurrence rate, which were less seen in similar studies. We analyzed CSS because elderly patients with CRC passed away not only for malignant reasons but also for multiple causes related to aging, and can result in significant reduction in OS. In this study, the CSS rate for each TNM group was about 15%-30% higher than the OS rate. Hinoi and his colleague reported that the 3-year CSS rates for both colon and rectal cancer patients aged over 80 were about 86.5% to 93.4%, similar to our result (88%). For elderly patients, once the recurrence occurred, they may not be able to tolerate recurrence treatment compared to younger patients. Cumulative recurrence was analyzed in this study for evaluating the efficacy and oncological quality of open surgery and laparoscopic surgery. The cumulative recurrence rate was similar in each TNM stage group and few studies had mentioned this. According to our results, laparoscopic surgery for CRC treatment in elderly patients, could be used as a standard method for radical resection of malignancies.
The present study has some potential limitations. First, this is a retrospective study conducted at a single institute while collecting data prospectively and is subject to various biases. Second, the selection bias is an essential issue because the choice of laparoscopy or laparotomy surgery is very subjective to surgeons’ preference, although the long-term outcome was compared with each stage.