Laparoscopic colorectal resection: short-term outcomes after 60 procedures – A single center initial experience

Background/Aim. Laparoscopic colorectal surgery is now widely accepted surgical method in the treatment of malignant and benign colorectal diseases. It is getting constantly more supporters due to its positive effects on enhanced patient recovery. The aim of this study was to determine the safety of minimally invasive approach as well as perioperative data, oncologic results and postoperative data. Methods. Prospective observational cohort clinical study was carried out at the Department for Colorectal and Pelvic Oncologic Surgery, First Surgical University Hospital, Clinical Center of Serbia, Belgrade. We analyzed demographics records concerning the type of surgery, clinicopathological features and oncological data for all operated patients. Records on early postoperative follow-up were also evaluated. Results. Laparoscopic colorectal resection was performed in 60 patients. Mean age of patients was 65 (29–87) years. Majority of patients were man, 37 (62%) of them. The most common indication was colorectal cancer (43 patients, 71.6%); 12 (20%) patients were operated due to the colorectal polyps unfitted for colonoscopic resection and 5 (8.3%) were operated due to Crohn’s disease. Average number of lymph node harvested in patients with colorectal carcinoma was 22.5 (6–52). We achieved negative resection margins in all patients operated due to carcinoma. Mean duration of hospital stay was 5 (4–12) days. Postoperative complications were encountered in 5 (8.3%) patients. Overall mortality rate was 1.7% (1 patient died due to thromboembolism). Conclusion. This study showed that initiation of laparoscopic colorectal resection is feasible and safe with short hospital stay, adequate oncologic resection and number of lymph node harvested.


Introduction
Laparoscopic colorectal surgery is developing strongly, and is becoming the mainstay treatment option for colorectal cancer and benign colorectal diseases in developed countries. It has been recognized as a first treatment option for colorectal cancer according to some leading surgical associations. The first colorectal laparoscopic resection was reported by Jacobs et al. 1 in 1991, while Watanabe et al. 2 were first to report results of laparoscopic colorectal resection for colon cancer in 1993 2 .
In the development of the procedure laparoscopy was reserved for smaller, early cancers. For instance, starting in 1996, health insurance in Japan covered expanses of laparoscopic colorectal resection only for early stages cancer. With the advance of surgical technique and followed with technological innovations, laparoscopy was introduced for larger and advanced tumors, and currently is being recognized as equally effective to open colorectal resection even for this indication 3,4 . According to Japan's National Registry for Colorectal Cancer, 40,000 colorectal resections are being performed yearly, which compeers number of open procedures. The trends are similar in Europe; for example, in Great Britain in 2012, 40% of colorectal resections were performed laparoscopically, comparing to only 5% in 2005 5 .
The reasons beyond the drawbacks in the development of laparoscopic colorectal surgery were technique difficulties, lack of clinical evidence, learning curve and fear of tumor spreading during laparoscopy. Current evidence, however, strongly suggest that there are no statistically significant differences between open and laparoscopic surgery regarding the incidence of tumor local recurrence, distant metastases or disease free survival [6][7][8][9] .
Proper surgical training, as well as prior experience with open procedures must back up the initiation of laparoscopic colorectal surgery. The goal of this study was to present the initial experience of single institution with the special emphasis on safety ie. early complication rate analysis 5 .

Methods
This prospective observational cohort clinical study was conducted at the Department for Polorectal and pelvic Sncologic surgery, First Surgical University Hospital, Clinical Center of Serbia, Belgrade starting from January 2015 till January 2018.
The study included 60 patients in whom laparoscopic colorectal resection was performed for benign and malignant colorectal diseases. The database was created and tracked prospectively and included: demographic data, records about surgical intervention, and in colorectal carcinoma cases, his-tological report which included TNM tumor stage, number of lymph nodes harvested and surgical margins analysis. For the purpose of this study 30 days follow-up data were analyzed with the intent of early postoperative complications evaluation.
Primary aim was safety of minimally invasive (MI) approach, while secondary aims were perioperative data (duration, blood lose), oncological results (number of lymph nodes) and postoperative data (excluding complications).
Prior to surgery all patients underwent diagnostic protocol, which included colonoscopy, rigid rectoscopy, abdominal and pelvic computed tomography and pelvic magnetic resonance imaging (MRI) scan for rectal carcinoma. The preoperative radiographic tumor stage was given for all patients with colorectal cancer, regarding the locoregional tumor status and presence of distant metastases.
All patients were properly informed about the surgical intervention and signed informed consent.
Preoperative bowel preparation was performed using the polyethylene glycol solutions. Prophylactic antibiotics and low molecular weight heparin were routinely employed.

Surgical technique
The patients were placed supine, with head down position. The peritoneal cavity was accessed with open Hasson approach and the carbon dioxide was insufflated, maintaining the intraabdominal pressure of 10-12 mmHg. In the case or colorectal cancer surgical resection was performed according to The American Joint Committee on Cancer (AJCC) recommendations 10 .
In the case of right colectomy, extracorporeal hand sewn anastomosis was performed. In the case of left colon or rectal cancer intracorporeal anastomosis was performed using "double stapler technique".
All surgical specimens underwent detailed histopathological examination.
Postoperatively nasogastric tube was kept for couple of hours (until patients were full awake); peroral intake of clear fluids was initiated at the day of surgery, followed by soft food diet on the first postoperative day. Abdominal drain was extracted on the second postoperative day. First regular clinical check-up was conducted 30 days after surgery, earlier in case if patients reported any kind of digestive symptomatology. Operative morbidities were defined as complications that lead to prolonged hospitalization or any type of other medical intervention including reoperation, induced by operative treatment.
Morbidity was reported according to the National Cancer Institute Common Toxicity Criteria: grade I of postoperative complications -asymptomatic or mild symptoms (clini- cal or diagnostic observations only); grade II -moderate (minimal, local or noninvasive intervention indicated; limiting age-appropriate instrumental activities of daily living -ADL); grade III -severe or medically significant but not immediately life threatening (hospitalization or prolongation of existing hospitalization indicated; disabling; limiting selfcare ADL); grade IV -life-threatening consequences (urgent intervention indicated), and grade V -death 11 .

Results
At the Department for Colorectal and Pelvic Oncological Surgery, 60 patients underwent laparoscopic colorectal resection in the observed period due to malignant and benign lesions. Mean age of patients was 65 (29-87) years. Majority of patients were man, 37 (62%) of them. The most common indication was colorectal cancer -43 (71.6%), 12 (20%) patients were operated due to the endoscopically unresectable colonic polyp resection and 5 (8.3%) were operated due to Crohn's disease.
Detailed number and type of the surgical procedures performed is shown in Table 1. In patients with colorectal cancer, average number of lymph nodes harvested was 22.5 (6-52). Results of the histopathological analysis are shown in Table 2.

T -tumor; N -node
Mean duration of the procedure was 182 min (range 120-270 min). The duration of the procedure was influenced by the learning curve, since the mean duration of the last 10 procedures was 155 min. Mean duration of ileocecal resection and right hemicolectomy was 169 min (range 120-252 min), for left hemicolectomy and high anterior resection 202 min (156-246 min) and for low anterior resection with or without ileostomy 232 min (192-270 min). Among the 7 (7/67, 10.4%) patients who underwent laparoscopic conversion to open surgery, five conversions were performed due to huge body mass index (BMI), one because of the bowel distension caused by intestinal occlusion and one due to the peritoneal dissemination.
Mean duration of hospital stay was 5 (4-2) days. Postoperative complications were encountered in 5 (8.3%) patients. Three patients were conservatively treated due to the postoperative bowel paresis (Grade III), one patient was reoperated due to colonic ischemia (Grade IV) and one patient suffered a myocardial infarction followed with massive mesentery thrombosis. This patient was reoperated and died on the 30th postoperative day due to another myocardial infarction (Grade V). Overall, mortality rate in this study population was 1.7%.

Discussion
This clinical study was performed in order to present initial experience in performing laparoscopic colorectal resections in the high volume center, specialized in colorectal cancer and pelvic oncology surgery, with a high number of oncological procedures performed by open surgery. Primary endpoint was safety of MI approach. Secondary aims were perioperative data (duration), oncologic results (number of lymph nodes) and postoperative data (excluding complications).
In this study 7 patients underwent conversion to open procedure (7/60), or 11.6% of overall procedures number, which is comparable with the literature results, especially those analyzing learning curve [12][13][14] . If we analyze the number of conversions to open surgery per year, there is a significant drop (3 conversions in first and second year, one conversion in third year). Five conversions were performed due to huge body mass index (BMI), one because of the bowel distension caused by intestinal occlusion and one due to the peritoneal dissemination. This can also be partially explained by a learning curve. It is now a standpoint that patients with high BMI and visceral adiposity have the biggest advantage with MI surgical treatment. However, one must observe that those patients are being operated only by the experienced (high volume) surgeons 15 .
Incidence of complications is not statistically different when results of open surgery are compared with laparoscopic surgery 16,17 . In this study early postoperative complications were observed in 5 (8.3%) patients. These results partly coincide with the ones reported in huge surgical series with MI colorectal resections such as study by Juo et al. 18  In our study population we did not encountered pulmonary complications, which coincide with the results of Owen et al. 20 who found significantly less pulmonary complications in patients who were treated laparoscopically opposed to the open surgery.
Average length of hospitalization was 5 (4-12) days, which is comparable with other studies with laparoscopic colorectal resections where average hospital stay duration is reported in range from 4 to 9.7 days [19][20][21][22] . The longest hospital stay (12 days) was observed in a patient who had ischemic damage of the colon postoperatively. The hospital stay for patients with postoperative intestinal paresis was 9-10 days.
Mean duration of the procedure was 182 min (range 120-270 min), which is in concordance with the other clinical studies, where mean duration was reported to range between 159 and 297 min 23,24 . One important remark when it comes to the mean operative time should be taken into consideration. The procedures for the rectal cancer are more complex, and time consuming than those for the right or left colon. In our study mean operative time was longer for procedures conducted on the rectum than those conducted on the right colon. The operative time was, as expected, influenced with the learning curve, and was significantly shorter in last 10 procedures. Having this in mind, we should approach the results of study by Prakash et al. 22 who have reported the mean operative time of 297 min, but for rectosigmoidal can-cer, and with the results from initial learning curve included. The shortest mean operative time was reported by Kiran et al. 24 , 146 minutes, but their study included resection of the right and left colon.
Our study showed that laparoscopic colorectal resection is not inferior to the open procedure when it comes to oncologic issue. According to AJCC, one needs to harvest minimally 12 lymph nodes to have the proper tumor staging 25 . Average number of harvested lymph nodes in our study was 22.5 (ranging 6-25), which makes it sufficient enough.
The study limitations are small number of patients and a short follow-up interval. Another important limitation is absence of the control group, presumably in this case, patients with similar characteristic who were treated with open surgery.

Conclusion
This study showed that initiation of laparoscopic colorectal resection is feasible with low rate of postoperative complications, short hospital stay, adequate oncologic resection and number of lymph node harvested. This is the reason why MI becomes a standard in the surgical treatment of colonic and rectal diseases.