The following is a summary of “Lateral Lymph Node Size and Tumor Distance From Anal Verge Accurately Predict Positive Lateral Pelvic Lymph Nodes in Rectal Cancer: A Multi-Institutional Retrospective Cohort Study,” published in the June 2023 issue of Colon and Rectum by Bae et al.
Lateral pelvic lymph node dissection enhances oncological outcomes in individuals diagnosed with rectal cancer who exhibit indications of lateral pelvic lymph node metastasis. Nevertheless, the medical expression for this procedure remains uncertain. This study sought to identify the prognostic factors for lateral lymph node metastasis and the criteria for performing lateral pelvic lymph node dissection. This clinical investigation comprised a cohort of 105 individuals diagnosed with locally advanced mid/low rectal cancer and exhibiting clinical indications of lateral pelvic lymph node metastasis. These patients underwent a surgical procedure known as total mesorectal excision, which involved the removal of both the rectal tumor and the adjacent lymph nodes in the pelvic region. The study was conducted over a period spanning from 2015 to 2020.
The indications were established based on preoperative factors associated with metastasis of lateral pelvic lymph nodes. Of 105 patients, 36 (34.3%) were diagnosed with lateral pelvic lymph node metastasis through pathological examination. Additionally, 77 patients (73.3%) received preoperative chemoradiation treatment. Tumors situated within a 5 cm proximity from the anal verge (P = 0.02) and initial node size ≥ 6 mm (P = 0.001) were observed to be significant indicators of lateral pelvic lymph node metastasis. The sensitivity was 100% (36/36) with a cutoff of 6 mm for the initial node size and 94.4% (34/36) with a cutoff of 8 mm for the initial node size. When employing initial node size cutoffs of 8 mm for the distance between the anal verge and the tumor greater than 5 cm and 6 mm for the distance between the anal point.
The tumor was less than or equal to 5 cm, and the sensitivity of metastasis in the lateral pelvic lymph nodes was 100%. The limitations of this study included a retrospective design and a small sample size, which may have impacted the findings. The size of the initial node and the tumor’s height were significant indicators of metastasis in the lateral pelvic lymph nodes. This study suggested that a minimum node size of 8 mm or more prominent, with a distance of more than 5 cm between the anal verge and the tumor, and a minimum node size of 6 mm or more significant, with a length of 5 cm or less between the anal point and cancer, are the most suitable criteria for performing lateral pelvic lymph node dissection in cases of rectal cancer.
