Positive lateral pelvic lymph nodes in low rectal cancer: should we change our practice now?

• Published in: ANZ journal of surgery Vol. 91; no. 5; pp. 947 - 953
• Main Authors: Gartrell, Richard, Hong, Michael K.‐Y., Baker, Ali, Master, Mobin, Gibbs, Peter, Arslan, Janan, Croxford, Matthew, Yeung, Justin M., Faragher, Ian G.
• Format: Journal Article
• Language: English
• Published: Melbourne John Wiley & Sons Australia, Ltd 01.05.2021; Blackwell Publishing Ltd
• Subjects: Cancer; Chemoradiotherapy; Colorectal cancer; lateral lymph node; lateral lymph node dissection; local recurrence; Lymph nodes; Lymphatic system; Metastases; Metastasis; neoadjuvant chemoradiotherapy; Patients; rectal cancer; Rectum; Surgery; Survival; neoadjuvant chemoradiotherapy; lateral lymph node dissection; local recurrence; lateral lymph node; rectal cancer
• ISSN: 1445-1433; 1445-2197
• DOI: 10.1111/ans.16779

Background The role of lateral lymph node dissection (LLND) in the treatment of patients with low rectal cancer with enlarged lateral lymph nodes (LLN+) is under investigation. Enthusiasm for LLND stems from a perceived reduction in local recurrence (LR). We aimed to compare the LR rate for LLN+ patients with LLN− patients, treated with neoadjuvant chemoradiotherapy (nCRT) and surgery, in a hospital that does not perform LLND. Methods A retrospective study of all patients with clinical stage 3 low rectal cancer who completed nCRT and surgery between 2008 and 2017 at Western Health was performed. Outcomes for LLN+ patients were compared with LLN− patients. The primary outcome was LR. Secondary outcomes included distant metastases, disease‐free survival and overall survival. Results There were 110 patients treated for stage 3 low rectal cancer over 10 years. There was no significant difference in the LR rate, with one LR from 28 LLN+ patients and one LR from 82 LLN− patients (4% versus 1.2%, P = 0.44). There were no significant differences in median disease‐free survival (41 versus 52 months, P = 0.19) or mean overall survival (62 versus 60 months, P = 0.80). Of all patients studied, 21% developed distant metastases. Conclusion LR after nCRT and surgery in patients with stage 3 rectal cancer is rare, irrespective of lateral pelvic node status. These data, along with the uncertain benefit and known risks of LLND, supports the continued use of standard therapy in these patients. Strategies to address distant failure in these patients should be explored. We were unable to find a difference in the local recurrence rate for patients with low rectal cancer, with and without enlarged lateral pelvic sidewall nodes, treated with neoadjuvant chemoradiotherapy and total mesorectal excision surgery alone. Our data do not support the adoption of lateral node dissection in these patients but rather emphasize the importance of exploring systemic strategies to address distant failure.