# Evaluation of Short-Term Postoperative Outcomes of Lateral Lymph Node Dissection After Neoadjuvant Radiotherapy for Rectal Cancer Patients: The Early Learning Phase After Surgical Training in the Netherlands

## TL;DR

This study assesses the early outcomes of lateral lymph node dissection after neoadjuvant radiotherapy for rectal cancer in the Netherlands, showing acceptable complication rates and good cancer control.

## Contribution

The study evaluates the implementation and outcomes of LLND in a real-world setting after surgical training in the Netherlands.

## Key findings

- Minimally invasive LLND had acceptable complication rates with 54% experiencing complications, 21% grade 3 or higher.
- 41% of LLND specimens contained malignant lymph nodes, and no ipsilateral LLRs occurred.
- The 18-month local recurrence rate was 14%, and disease-free survival was 55%.

## Abstract

Distal, locally advanced rectal cancer might spread to lateral lymph nodes (LLNs), posing a risk of lateral local recurrence (LLR). This study evaluated quality-controlled implementation of lateral lymph node dissection (LLND) in the Netherlands.

This retrospective multicenter cohort study included consecutively treated rectal cancer patients who underwent neoadjuvant therapy, total mesorectal excision (TME) surgery, and nerve-sparing minimally invasive LLND by trained surgeons across 10 Dutch hospitals. Training involved cadaver sessions, monthly video meetings, and proctoring. Outcome measures included intra- and postoperative complications, urogenital dysfunction and 18-month LLR, local recurrence (LR), and disease-free survival (DFS).

The study comprised 41 patients (median follow-up period, 16 months; interquartile range, IQR, 8–21 months) with advanced tumors (27% cT4, 49% cN2, 7% cM1), and a mean LLN size of 11 mm on primary-staging MRI. Abdominoperineal resection was performed for 29 patients (70%). A beyond TME procedure was performed for 11 patients (28%). The median blood-loss was 250 ml (IQR, 100–400 ml), with obturator nerve injury reported in one patient. Malignant LLNs were found in 41% of the LLND specimens. Complications occurred for 22 patients (54%), 21% (9/41) of which were grade 3 or higher. Nine patients (22%, four of whom underwent beyond TME surgery) had a Foley or intermittent urinary catheter at the end of the follow-up period. Sexual dysfunction of three patients was reported. No ipsilateral LLRs occurred. The 18-month LR rate was 14%, and the DFS was 55%.

Minimally invasive nerve-sparing LLND by trained Dutch surgeons showed acceptable complication rates and good oncologic control of the lateral compartment to date.