Should No.253 lymph nodes be dissected routinely in laparoscopic radical resection of colorectal cancer?

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Abstract Background Laparoscopic radical resection of colorectal cancer (CRC) has become the most important treatment for resectable CRC. However, it is still controversial whether No.253 lymph nodes should be routinely dissected during radical resection of sigmoid colon cancer and rectal cancer. Patients and methods: From June 2016 to January 2019, 508 patients with sigmoid or rectal cancer received surgical treatment in the Sixth Affiliated Hospital of Sun Yat-sen University were enrolled in this retrospective cohort study. Patients were divided into No.253 LN dissection group (n = 220) and No.253 LN preservation group (n = 288) according to whether No.253 LN were removed during operation. Propensity score matching (PSM) was used to adjust the differences in baseline characteristics. The incidence of postoperative complications and survival rate related results were analyzed after PSM. Results 294 patients were equally divided into No.253 LN dissection group (n = 147) and No.253 LN preservation group (n = 147) after PSM. There were no statistically significant differences in overall survival (OS), progression-free survival (PFS), recurrence free survival (RFS) and distant metastasis-free survival (DMFS) between the two groups (P value was 0.054, 0.159, 0.837 and 0.143 respectively). Though, No.253 LN-positive group had a shorter OS (P = 0.003) and PFS (P = 0.004), a low positive rate (4/220) of No.253 LN metastases was observed. CT or MRI in assessment of LN involvement reveal that LN diameter ≥ 5mm in diameter indicated a higher discrimination accuracy, which should be paid attention in clinical practice. Conclusion Routine dissection of No.253 LN is not necessary for all patients with sigmoid colon cancer or rectal cancer but is performed in specific cases. For certain cases, such as in patients with regional LN ≥ 5mm, especially ≥ 10mm, evaluated by preoperative CT/MRI, dissection of No.253 LN should be considered into clinical practice.