Evaluation of National Surgical Practice for Lateral Lymph Nodes in Rectal Cancer in an Untrained Setting

Abstract

Background Involved lateral lymph nodes (LLNs) have been associated with increased local recurrence (LR) and ipsi-lateral LR (LLR) rates. However, consensus regarding the indication and type of surgical treatment for suspicious LLNs is lacking. This study evaluated the surgical treatment of LLNs in an untrained setting at a national level. Methods Patients who underwent additional LLN surgery were selected from a national cross-sectional cohort study regarding patients undergoing rectal cancer surgery in 69 Dutch hospitals in 2016. LLN surgery consisted of either ‘node-picking’ (the removal of an individual LLN) or ‘partial regional node dissection’ (PRND; an incomplete resection of the LLN area). For all patients with primarily enlarged (≥7 mm) LLNs, those undergoing rectal surgery with an additional LLN procedure were compared to those undergoing only rectal resection. Results Out of 3057 patients, 64 underwent additional LLN surgery, with 4-year LR and LLR rates of 26% and 15%, respectively. Forty-eight patients (75%) had enlarged LLNs, with corresponding recurrence rates of 26% and 19%, respectively. Node-picking (n = 40) resulted in a 20% 4-year LLR, and a 14% LLR after PRND (n = 8; p = 0.677). Multivariable analysis of 158 patients with enlarged LLNs undergoing additional LLN surgery (n = 48) or rectal resection alone (n = 110) showed no significant association of LLN surgery with 4-year LR or LLR, but suggested higher recurrence risks after LLN surgery (LR: hazard ratio [HR] 1.5, 95% confidence interval [CI] 0.7–3.2, p = 0.264; LLR: HR 1.9, 95% CI 0.2–2.5, p = 0.874). Conclusion Evaluation of Dutch practice in 2016 revealed that approximately one-third of patients with primarily enlarged LLNs underwent surgical treatment, mostly consisting of node-picking. Recurrence rates were not significantly affected by LLN surgery, but did suggest worse outcomes. Outcomes of LLN surgery after adequate training requires further research.

Prognostic Implications of Lateral Lymph Nodes in Rectal Cancer: A Population-Based Cross-Sectional Study with Standardized Radiological Evaluation after Dedicated Training

“…Our research group is examining the irradiation doses received by patients with LLNs ≥5 mm and the outcomes after LLN surgery (not LLND; separate articles). 10 , 22 We hypothesize that the majority of LLNs received an adequate dose, meaning that surgical treatment might be imperative to improve oncological outcomes for this population in the future.…”

“…This could not be performed for LLR due to low event rates. Surgical treatment of LLNs was not routine practice and was only incidentally performed without standardized technique; therefore, LLN surgery was not included in the prognostic models (details of patients who underwent LLN surgery are described elsewhere) 10 . Statistical significance was set at a p value of <0.05.…”

Coverage of Lateral Lymph Nodes in Rectal Cancer Patients with Routine Radiation Therapy Practice and Associated Locoregional Recurrence Rates

“…None were formal LLND. A separate analysis of patients undergoing LLN-surgery in 2016 revealed similar long-term LLR rates for these patients compared with those who did not undergo additional surgery (around 15%), 25 highlighting the inexperience of Western surgeons with these procedures. Because additional LLN surgery was not standard in the Netherlands in 2016 and did not positively influence LLR rates, it has not been considered separately.…”

Value of Size and Malignant Features of Lateral Lymph Nodes in Risk Stratification at Lateral Local Recurrence of Rectal Cancer: A National Cohort Study

“…None underwent formal LLND. 20 Oncologic outcomes for these patients versus those without LLNs or those who did not receive neoadjuvant therapy were previously published. 11 Patients were excluded if they had synchronous DMs (within 3 months of surgery), were treated according to a watch-and-wait protocol (due to incomplete registration in the DCRA database), or had only external iliac or long-stretched obturator LLNs (short axis ,5.0 mm, long axis:short axis ratio of $2:1, and no malignant features) because previous research showed they did not result in LLRs.…”