Preoperative biopsy and intraoperative tumor diameter predict lymph node dissemination in endometrial cancer

To determine whether preoperative biopsy (grade and histology) and intraoperative tumor diameter (TD) predict lymph node dissemination (LN+) and lymph node recurrence (LNRec) in endometrial cancer (EC).

Patients who underwent EC surgery from 2004 to 2008 were stratified into risk categories. Cases with preoperative grade 3 or non-endometrioid histology were classified as high risk (HR). Patients with preoperative FIGO grade 1 or 2, endometrioid histology or complex and/or atypical hyperplasia were classified based on intraoperative findings: (a) intraoperative macroscopic extrauterine disease classified as HR; (b) largest TD>2 cm classified as intermediate risk (IR) and (c) TD ≤ 2 cm classified as low risk (LR). LN+ and LNRec rates were determined.

Of 704 patients evaluated, 188 were HR (27%), 350 IR (50%), and 166 LR (23%). P/PA lymphadenectomy was performed in 87% HR, 83% IR and 16% LR patients. LN+ and/or LNRec occurred in 51 HR patients (27%) and 39 IR patients (11%). Only 1 LR patient (0.6%) had LN+ and none had LNRec. Four LR patients (2%) required adjuvant therapy according to permanent section pathology.

Preoperative biopsy and intraoperative TD can be used to effectively stratify patients into LR, IR or HR subgroups to tailor surgery. LR patients have a low probability (<1%) of LN+ and/or LNRec and lymphadenectomy can be omitted in this group. HR and IR patients combined (3/4 of population) have a substantial risk of LN+ or LNRec (17%). Lymphadenectomy is proposed to be advantageous in HR and IR patients if accurate frozen section is lacking.