The importance of training and education in performing total mesorectal excision in rectal cancer surgery

Background/Aim . In the last two decades there has been a significant progress in rectal cancer surgery. Preoperative radiotherapy, the introduction of staplers and largely improved surgical techniques have greatly contributed to better treatment outcomes, primarily by reducing the frequency of early surgical complications and the rate of local recurrence. The aim of this study was to compare operative and postoperative results in the treatment of rectal cancer between the two groups of surgeons – those who are closely engaged in colorectal surgery and those who deal with these issues sporadically. Methods . This retrospective study included 146 patients who had underwent rectal cancer surgery at the Institute of Oncology of Vojvodina in the period from January 1, 2008 to December 31, 2010. The patients were divided into two groups, the group N1 of 101 patients operated on by trained colorectal surgeons, and the group N2 of 45 patients operated on by surgeons without training in totalmesorectal excision (TME). Results . Preoperative chemoradiotherapy was received by 49 (33.56%) of the patients. A statistically significant difference between the two groups was noted in the duration of surgery and the need for blood transfusion during surgery. Anastomotic leakage occurred in 3 patients from the group N1 and in 10 patients from the group N2. Seven (4.79%) of the patients developed local recurrence after surgical treatment. There were significant differences in local recurrence rate and anastomotic leakage rate between the compared groups. Conclusion . It is necessary to continue education and training in surgery for rectal cancer to master new technologies and surgical techniques and to improve the results of surgical treatment.


Introduction
Preoperative staging, use and timing of neoadjuvant and adjuvant chemioradiotherapy (CRT), surgical technique, reconstructive options and protocols in the management of rectal cancer have evolved over the past two decades [1][2][3][4][5] .
As a result, the management of patients with rectal cancer has become highly complex, so it is essential that surgeons acquire and maintain knowledge of rectal cancer treatment issues [6][7][8][9] .
The importance of surgeon knowledge and training was illustrated in a study of Richardson et al. 6 in which patients with rectal cancer were more likely to receive sphincterpreserving surgery and were less likely to experience local recurrence if they were treated by a surgeon with greater knowledge of rectal cancer care.
The aim of the study was to compare operative and postoperative results of rectal cancer surgical treatment performed by two groups of surgeons, the first one of highly skilled and educated colorectal surgeons, and the second one of surgeons performing colorectal operations sporadically. The presence of operable secondary deposits in the liver and/or lungs did not exclude patients from the study.

This
Rectal adenocarcinoma (3-18 cm from the anal verge), after colonoscopy and histopathological (HP) examination of the tumor, was verified in all the patients (146, 100.00%).
Preoperative chemoradiation therapy (CRT) was performed with the total dose of 50.4 Gray (Gy) divided into 25 fractions, with the daily dose of 1.8 Gy. Chemotherapy was carried out with radiation therapy in order to increase the sensitivity of tumor tissue to radiation. The patients received calcium 5-fluorouracil and leucovorin (5-FU/LV), on the day 1, 2, 10, 11, 20 and 21 of radiotherapy. Surgery was performed 8 to 10 weeks after the completion of CRT.
We performed low anterior resection (LAR) or high anterior resection (HAR), both with total mesorectal excision (TME) and by using single or double stapler technique for creation of colorectal anastomosis.
Software SPSS V. 16. was used for the purposes of statistical analysis. All the data were statistically analyzed (per-centage, average value, range) and presented in tables. Both Fischer's exact tests and χ 2 tests were used to compare the data between the groups. Values of p < 0.05 were considered as statistically significant.

Results
The average distance from the anal verge in the group N1 was 8.72 cm, while in the group N2 it was 9.16 cm. Tumor in the distal rectum (3-7 cm) was present in 52 (35.62%) of the patients. Among the total number of patients, distant metastases were found in 17 (11.64%) of the patients, in the liver (14 patients) and in the lungs (3 patients). A certain number of patients were classified as ASA 2 (49.32%).
Histopathological analysis showed a moderately differentiated tumor (GII) in most of the patients (71.92%). The majority of patients (82 (56.16%)) had no metastases in the lymph nodes (Table 1).
Anasthomosis was performed with double stapler technique in 110 (75.34%) of the patients, and by single stapler technique in 36 (24.66%) of the patients in both groups. For the group N1, the mean operation time was 104 min, and in the group N2 136 min (a statistically significant difference with p = 0.000001). Fifty-seven of the patients needed blood transfusion, from the group N1 21, and from the group N2 36 (p = 0.00003).
Protective transversostomy was performed in 27 of the patients from the group N1 and in 10 patients from the group N2.
Preoperative CRT was received by 49 (33.56%) of the patients, 42 in the N1 and 7 in the group N2 (Table 2).
Anasthomotic leakage was noticed in 3 of the patients from the group N1 and in 10 from the group N2. This difference was statistically significant (p = 0.0004).
Seven (4.79%) of the patients (2 from the N1 and 5 from the group N2) developed a local recurrence, which is a statistically significant difference between the two groups in the local recurrence rate. Due to the postoperative complications, 6 of the patients died a month after the operation (Table 3).

Discusion
Improved screening, surgical techniques, a more effective chemotherapy, radiation therapy and improved imaging have lead to better results in rectal cancer treatment.
Many authors have shown improved outcomes among patients with rectal cancer who were treated by surgeons with subspecialty training (colorectal surgeons) [6][7][8] . This includes increased use of sphincter-preserving surgery, decreased local recurrence 8 , decreased anastomotic leakage 9 , decreased postoperative mortality and improved survival 10 . This variation in the outcome may reflect on the differences in surgical technique, especially in the technique of TME [11][12][13] .
Anastomosis distance from the anal verge and preoperative CRT are one of the most important risk factors for anastomotic leakage 1, 2, 10, 14-16 .
In their study on 1,014 patients, Vignali et al. 15

ASA -American Society of Anesthesiology; CRT -chemioradiation therapy; N 1 -group of patients operated on by trained colorectal surgeon; N 2 -group of patients operated on by general surgeon;
n -number of patients.  in the entire group. However, for tumors localized less than 7 cm from the anal verge, clinical signs of anastomosis leakage had 7.7%, and for tumors localized in the proximal portion of the rectum in 1% of cases 15 . Our results are compatible to the results of other authors 10,[13][14][15][16][17] . Anastomotic leakage rate in the group N1 of the patients was low, despite the fact that they were far more radiated than the patients in the group N2 (42% vs 15%). Therefore, hypothetically speaking the group N2 had pointed to the more inferior results in the rate of anastomotic leakage than the group N1.
The importance of training and education in TME is particularly reflected on the duration time of surgery. We found a statistically significant difference in the mean time of the operation between the two groups of surgeons. Other authors came to the same conclusions [6][7][8][9][10]18 . This can also be used when the need for intraoperative blood transfusion is concerned 6-10. The single and double stapling techniques are equally safe. Radovanovic et al. 16 in their study found no significant difference in the anastomotic leakage rate between these techiques 16 . However, double stapling technique allows the anastomosis to be performed very low in the pelvis and operative time is shortened than in single stapling technique 15,16 .
Protective stomas do not prevent anastomosis leakage. However, stomas reduce the consequences of complications in terms of reoperations. Also, they reduce the clinical manifestations of anastomotic leakage. Norwegian multicentric randomized study, Rectal Cancer Trial On Defunctioning Stoma (REKTODES) has clearly demonstrated that protective stoma significantly reduces the incidence of symptoms of anastomotic leakage 17 . We believe that we should create protective stoma in the following cases: at very low rectal resection, when rings of staples are incomplete after resection, when the water test is positive and in patients with severe general condition.
According to our institutional protocol for rectal cancer treatment, all patients with locally advanced tumors should receive preoperative CRT. Preoperative CRT can improve local control of the disease 1-5 . In a Swedish rectal cancer trial, the reduction in the rate of local recurrence from 27% in the surgery-only group, to 11% in the radiotherapy-plussurgery group. Also, the rate of overall survival is improved from 48% in the surgery-only group to 58% in the combinedtreatment group 19 . Local recurrences after surgery only performed by general surgeons vary widely from 15% to 45%, and by contrast, surgeons who specialize in TME (dedicated colorectal surgeons) report local-recurrence rates of 7% or less 6-12, 18, 20 . Accordingly, our study shows 3.42% vs 1.37% local recurrence rate, respectively.

Conclusion
It is necessary to continue professional development in rectal cancer surgery in order to maintain existing, and also to acquire new knowledge. Therefore, it is essential to be familiar with new technologies and surgery techniques to offer maximum quality of surgical treatment to rectal cancer patients.