Variables Impacting Lymph Node Recovery in Colectomy Resection Specimens Removed for Colorectal Adenocarcinoma

ABSTRACT

Recent data suggest that a higher number of nodes evaluated in colectomy specimens for colorectal adenocarcinoma is associated with increased survival. Recommendations mandate the harvesting of at least 12 nodes in colectomy specimens for adequate assessment. Recent studies argue that the above association is complex and is uncontrolled for a variety of variables.

The study's objective is to evaluate several factors that impact the harvesting of lymph nodes in colectomy specimen.

We reviewed 306 colectomy specimens from 2 academic medical centers, 177 from Kansas University Medical Center (KUMC) and 129 from the Kansas City Veterans Affairs Medical Center (VAMC) from 2000 to 2007.

Factors evaluated included tumor size, grade, stage, site, number of positive nodes and length of colectomy segment removed. We compared the number of nodes removed at the 2 institutions and whether individual surgeons had an impact on the number of harvested nodes.

Harvesting at least 12 nodes is correlated with larger tumor size, higher grade and stage and specimens longer than 21 cm. More nodes were harvested from the right colon (mean=13 nodes), followed by descending (12 nodes), transverse and rectosigmoid (10 nodes each). Number of positive nodes correlated with tumor grade, but not with tumor site, size, linear length of specimen or whether 12 nodes were harvested.

Cases from the VAMC were more likely to harvest 12 nodes compared to KUMC. It was noted that 2 of 10 surgeons at the VAMC performed 76% of all surgeries. There were 21 surgeons at KUMC; none performed more than 12% of the cases.

Number of harvested nodes is related to other prognostically significant parameters primarily related to tumor biology. The potential impact of surgeon's experience and the type of surgery performed needs further evaluation.

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