Feasibility of Laparoscopic Total Mesorectal Excision with Extended Lateral Pelvic Lymph Node Dissection for Advanced Lower Rectal Cancer after Preoperative Chemoradiotherapy

Oncological outcomes of robotic-assisted laparoscopic versus open lateral lymph node dissection for locally advanced low rectal cancer

BACKGROUND

The long-term outcomes of robotic-assisted laparoscopic lateral lymph node dissection (RALLD) have not been fully investigated. This study aimed to assess the oncological and long-term outcomes of RALLD for rectal cancer through comparison with those of open lateral lymph node dissection (OLLD) in a retrospective study.

METHODS

Between September 2002 and October 2014, the medical data of 426 patients who underwent total mesorectal excision with lateral lymph node dissection for primary rectal cancer were collected. Of these, 115 patients were excluded after data collection (stage IV, n = 61; total pelvic exenteration, n = 31; multiple cancer, n = 20; conventional laparoscopic surgery, n = 3). Before matching, 311 patients with clinical stage II/III were analyzed. Using exact matching, patients were stratified into RALLD (n = 78) and OLLD (n = 78) groups. Pathological findings and long-term outcomes were compared between the groups.

RESULTS

The pathological stage and number of harvested lymph nodes showed no significant differences between the groups. The rate of positive resection margin in the RALLD group tended to be lower compared with that of the OLLD group (p = 0.059). The median follow-up duration was 54.0 months in 156 patients. The 5-year overall survival rate was 95.4 and 87.8% in the RALLD and OLLD groups, respectively (p = 0.106). The 5-year relapse-free survival rate was 79.1 and 69.9% in the RALLD and OLLD groups, respectively (p = 0.157). The 5-year local relapse-free survival rate was 98.6 and 90.9% in the RALLD and OLLD groups, respectively (p = 0.029).

CONCLUSIONS

The short- and long-term outcomes indicated that RALLD may be a useful modality for locally advanced low rectal cancer.

Outcomes and prognostic factors of selective lateral pelvic lymph node dissection with preoperative chemoradiotherapy for locally advanced rectal cancer

PURPOSE

The clinical significance of preoperative chemoradiotherapy (CRT) and lateral lymph node dissection (LLND) for locally advanced rectal cancer remains unclear. We have employed total mesorectal excision and selective LLND following preoperative CRT for patients with locally advanced rectal cancer. The validity of our strategy was evaluated.

METHODS

A total of 45 patients with locally advanced rectal cancer who underwent curative surgery after CRT from November 2005 to September 2016 were retrospectively analyzed. LLND was performed only for the patients with lateral lymph nodes suspected to have metastasis based on the pretreatment images.

RESULTS

Rates of 5-year overall survival (OS) and 5-year relapse-free survival (RFS) were 85.7 and 61.8%, respectively. Univariate and multivariate analyses detected only histological response (grades 2 and 3 vs. grade 1) as a significant prognostic factor for OS and local recurrence. ypN and ypStage were significant factors for RFS by univariate analysis, while no significant factor was detected by multivariate analysis. There was no significant factor for distant recurrence. In good responders (grades 2 and 3), the local recurrence rate was 0% (P = 0.006, vs. grade 1), while distant recurrence developed in 4 of 20 cases (20%, P = 0.615, vs. grade 1). There was no local recurrence in LLND (-) group regardless the histological response.

CONCLUSIONS

Although selective LLND with preoperative CRT seems effective and valid for good responders, new treatment strategy is necessary for poor responders. Therefore, development of reliable biomarkers for histological response to CRT is an urgent need.