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Published on: February 12, 2022
What is the number of lymph nodes required for an "adequate" pelvic lymphadenectomy?
H W Nijman1, M Khalifa, A Covens
1Department of Obstetrics and Gynecology, Division of Gynecologic Oncology, Sunnybrook and Women's College Health Science Center, University of Toronto, Toronto, Ontario, Canada.
Purpose Of Investigation:
To establish a definition of an adequate number of lymph nodes identified at a pelvic lymphadenectomy through statistical methods.
Methods:
We conducted a retrospective study in cervical and endometrial carcinoma patients who underwent radical or staging surgery. The Student's t-test, Pearson's correlation, analysis of variance, and linear regression analysis were used.
Results:
Five hundred and ninety four-sided pelvic lymphadenectomies were analyzed. The mean (range) number of pelvic lymph nodes identifed was 11.3 (0-42). The 1st, 5th and 10th percentiles were three, five, and six lymph nodes respectively. The number of lymph nodes was higher in the laparoscopic approach compared to laparotomy (11.9 vs 10.6, p < 0.01).
Conclusions:
The number of lymph nodes identified at a pelvic lymphadencetomy vary with type of surgery. We propose that using the 1st, 5th or 10th percentile is reasonable for the definition of an adequate number of lymph nodes to be identified at a pelvic lymphadenectomy.

