Focusing on chylous ascites: a noteworthy complication after laparoscopic/robotic para-aortic lymphadenectomy in left-sided colorectal cancer in a high-volume single center.

BACKGROUND

This study aimed to evaluate the incidence, severity, and treatment modalities of chylous ascites after laparoscopic/robotic para-aortic lymph node (PALN) dissection for left-sided colorectal cancer (CRC).

METHODS

A cohort of 143 patients who underwent laparoscopic PALN dissection for left-sided CRC were included. The least absolute shrinkage and selection operator (LASSO) and logistic regression analysis were performed to identify risk factors for the occurrence of chylous ascites.

RESULTS

Chylous ascites occurred in 27 (18.8%) patients. Multivariate logistic regression analysis demonstrated that prognostic nutritional index (PNI ≤ 46, OR = 3.18, P = 0.03), use of indocyanine green (ICG) fluorescence imaging (OR = 2.92, P = 0.04), and number of total retrieved lymph nodes (LNs) > 25 (OR = 5.41, P = 0.01) were independently correlated with the occurrence of chylous ascites. A nomogram predicting postoperative chylous ascites was developed, with a C-index of 0.75. Based on the grading system, 63.0% (17/27) were classified as Grade A, 22.2% (6/27) as Grade B, and 14.8% (4/27) as Grade C. The use of ICG fluorescence during surgery and the number of total retrieved PALNs were correlated with prolonged resolution (Grade B/C) of chylous ascites (P = 0.02 and P = 0.04).

CONCLUSIONS

Postoperative chylous ascites represents a common and significant complication after laparoscopic/robotic PALN dissection for CRC surgery. PNI ≤ 46, ICG fluorescence imaging guidance, and total LN retrieval are independent risk factors. The use of ICG fluorescence during surgery and total retrieved PALNs are correlated with the prolonged resolution of chylous ascites. Further study is needed to validate these findings.