Does Reevaluation of Colorectal Cancers With Inadequate Nodal Yield Lead to Stage Migration or the Identification of Metastatic Lymph Nodes?

BACKGROUND: The National Comprehensive Cancer Network recommends routine reevaluation of all stage II colon cancer specimens with fewer than 12 lymph nodes. However, there are few data demonstrating the effect of reevaluation on stage. OBJECTIVE: The aim of this study was to demonstrate the effect of pathologic reevaluation for colorectal cancers with fewer than 12 lymph nodes on stage. DESIGN: This study entailed a retrospective review of pathology reports. SETTINGS: This study was conducted at 2 large multispecialty referral centers. INTERVENTIONS: Pathologic reevaluation was performed to look for additional lymph nodes. PATIENTS: All patients with stage I through III colorectal cancers with inadequate lymph node yields who underwent reevaluation from January 1, 2007 through March 31, 2011 were identified. MAIN OUTCOME MEASURES: We recorded initial pathologic stage and new stage following reevaluation. The following variables before and after reevaluation were also recorded: 1) total lymph node count, 2) metastatic node count, 3) negative node count, and 4) lymph node ratio. RESULTS: Eighty-three patients underwent pathologic reevaluation from a total of 1682 cancer specimens. Mean nodal yields were 7.2 2.6 on the first pathologic review. On reevaluation, 80% of patients had one or more newly identified nodes. On average, 6.9 9.6 more lymph nodes were identified with a metastatic node detected in 4 of 83 patients (4.8%). After pathologic reevaluation, 1 patient (1.2%) had a change in TNM stage from N1 to N2 disease. The lymph node ratio changed in 13 of 15 patients (87% of stage III cancers). Only 4 of these had a change in lymph node quartile. LIMITATIONS: The study was limited by its retrospective nature and small sample size. CONCLUSION: Few patients have a newly discovered metastatic node or stage change following pathologic reevaluation. The effect of pathologic reevaluation on treatment and outcome should be further investigated.