Does the size of pelvic lymph nodes predict metastatic involvement in patients with endometrial cancer?

Whether the size of a retroperitoneal lymph node reflects its status is not clear. We measured the size of 125 positive and 160 negative pelvic lymph nodes in 32 consecutive patients with node-positive endometrial cancer. The measurements were compared with those of 143 pelvic lymph nodes of five randomly selected patients with endometrial cancer without node involvement. Overall, positive lymph nodes were larger than negative lymph nodes in both node-positive patients and node-negative controls (P < 0.01). There was a positive correlation between the size of positive lymph nodes and the size of the metastasis therein (P < 0.01). However, 68 of 125 (54%) positive lymph nodes measured less than 10 mm in maximum diameter, while 46 of 160 (29%) negative lymph nodes in node-positive patients measured more than 10 mm in maximum diameter. The metastasis was detected in more than 50% of step-serial sections in only 74% of positive lymph nodes. These data suggest that the size of a lymph node does not reliably reflect its status. Thus, these nodes may be missed if only enlarged nodes are removed. If only one section of a lymph node is performed, at least 26% of metastases will be missed.