Intramural cancer recurrence in the rectum after curative surgery for proximal sigmoid colon cancer: a case report

Background

Intramural metastasis distant from the primary tumor is rare in colorectal cancer. Here, we present a notably rare and probably the first case of asynchronous intramural recurrence in the rectum after curative surgery for proximal sigmoid colon cancer.

Case presentation

A 44-year-old man underwent curative sigmoidectomy for proximal sigmoid colon cancer with T3N0M0, Stage IIA tubular adenocarcinomas. After 15 months, the tumor marker level had increased, and positron emission tomography-computed tomography (PET-CT) revealed abnormal fluorodeoxyglucose uptake in the rectum; colonoscopy revealed a submucosal tumor (SMT)-like lesion in the upper rectum, and biopsy revealed a tubular adenocarcinoma. We performed curative low anterior resection with tumor-specific mesorectal excision (TSME). The SMT-like tumor was located approximately 20 cm from the initial sigmoid colon anastomosis (i.e., at least 20 cm distal to the initial sigmoid colon cancer). The pathological findings revealed cancer cells with the same features as the initial sigmoid colon cancer, only in the intestinal wall but not in the mucosa and extramural tissue. Therefore, the lesion was determined to be an intramural recurrence.

After 24 months, lung recurrence, and local recurrence, which might have involved the lymph nodes in the preserved mesorectum after TSME at the bottom of the pelvis was detected on PET-CT. Hence, we started systemic chemotherapy.

Conclusions

This case report suggests that PET-CT and short-interval repeat colonoscopy may help detect a rare intramural recurrence. A long distal margin may be necessary to achieve local control in the rectal resection for intramural recurrence.

Surgical technique for mesorectal division during robot-assisted laparoscopic tumor-specific mesorectal excision (TSME) for rectal cancer using da Vinci Si surgical system: the simple switching technique (SST)

In a narrow pelvic cavity, performing sufficient tumor-specific mesorectal excision (TSME) is difficult. Even in robot-assisted laparoscopic surgery (RALS), mesorectal division is difficult in a narrow pelvic cavity. To overcome this difficulty, we invented a novel method of mesorectal division. In this new approach, we switched the fenestrated bipolar forceps and the double-fenestrated forceps with each other so that both instruments were placed on the same (right) side of the patient. After the mesorectal fat and vessels were coagulated using the fenestrated bipolar forceps, coagulated tissues were divided using the monopolar scissors in the same direction. We named this technique the "simple switching technique (SST)". We retrospectively collected data and evaluated the usefulness of SST in 24 consecutive patients who underwent RALS TSME between July 2018 and January 2020. Twelve patients underwent SST, and 12 patients underwent other conventional surgical methods (non-SST). The median operation time for mesorectal division was 809.5 s (range 395-1491 s) in the SST group and 985.5 s (range 493-2353 s) in the non-SST group. The coefficient of variation for non-SST was 0.545, which was > 1.5 times the coefficient of 0.360 for SST. Although no significant differences were found for operation time for mesorectal division, the operation time for mesorectal division by SST tended to be shorter than by non-SST (P = 0.157). No significant differences were found regarding short-term outcomes between the groups. SST is feasible and can be an optional method of mesorectal division in RALS TSME.

The feasibility of laparoscopic TSME preserving the left colic artery and superior rectal artery for upper rectal cancer

Background

Laparoscopic tumor-specific mesorectal excision (TSME) preserving the left colic artery and superior rectal artery is still a technically challenging procedure. We conducted this study to demonstrate the feasibility of this procedure for upper rectal cancer.

Methods

A total of 184 patients with upper rectal cancer were retrospectively analyzed in our cancer center between April 2010 and April 2017. These patients were treated with either laparoscopic TSME (n = 46) or laparoscopic total mesorectal excision (TME) (n = 138). In the TSME group, the left colonic artery and superior rectal artery were preserved while they were not in the TME group.

Results

The operation time in the TSME group was longer than that in the TME group (218.56 ± 35.85 min vs. 201.13 ± 42.65 min, P = 0.004). Furthermore, the number of resected lymph nodes in the TSME group was greater than that in the TME group (19.43 ± 9.46 vs. 18.03 ± 7.43, P = 0.024). The blood loss between the TSME and TME groups was not significant. No mortality occurred in either the TSME or TME groups. One patient in the TME group underwent conversion to laparotomy. The total postoperative complication rates in the TSME and TME groups were 8.7% and 17.4%, respectively. There was no difference in severe complications between the two groups (anastomotic leakage and stenosis).

Conclusions

Laparoscopic TSME preserving the left colic artery and superior rectal artery can be safely conducted for upper rectal cancer.

Oncologic Outcomes and Risk Factors for Recurrence after Tumor-specific Mesorectal Excision of Rectal Cancer: 782 Cases

Purpose

The aim of this study was to analyze the oncologic outcomes and the risk factors for recurrence after a tumor-specific mesorectal excision (TSME) of resectable rectal cancer in a single institution.

Methods

A total of 782 patients who underwent a TSME for resectable rectal cancer between February 1995 and December 2005 were enrolled retrospectively. Oncologic outcomes included 5-year cancer-specific survival and its affecting factors, as well as risk factors for local and systemic recurrence.

Results

The 5-year cancer-specific survival rate was 77.53% with a mean follow-up period of 61 ± 31 months. The overall local and systemic recurrence rates were 9.2% and 21.1%, respectively. The risk factors for local recurrence were pN stage (P = 0.015), positive distal resection margin, and positive circumferential resection margin (P < 0.001). The risk factors for systemic recurrence were pN stage (P < 0.001) and preoperative carcinoembryonic antigen level (P = 0.005). The prognostic factors for cancer-specific survival were pT stage (P < 0.001), pN stage (P < 0.001), positive distal resection margin (P = 0.005), and positive circumferential resection margin (P = 0.016).

Conclusion

The oncologic outcomes in our institution after a TSME for patients with resectable rectal cancer were similar to those reported in other recent studies, and we established the risk factors that could be crucial for the planning of treatment and follow-up.