Histological and immunohistochemical profiles predict lymph node status in women with low-intermediate risk endometrial cancer

Objective: The aim of this study was to build a model to predict the risk of lymph node metastases (LNM) in women with low- or intermediate-risk endometrial cancer (EC) using histological and immunohistochemical markers.

Methods: Samples were collected from 68 women with low- or intermediate-risk EC. European Society of Medical Oncology (ESMO) risk group, lymphovascular space involvement (LVSI), immunostaining expressions of Estrogen receptor (ER) and Progesteron receptor (PR) were used to build a recursive partitioning model to predict final lymph node status.

Results: The number of women with final low- and intermediate risk EC was 34 (50%) each. LVSI was present in 7 women with low-risk (20%) and 28 (80%) with intermediate-risk EC. Nineteen women (28%) had LNM at final histology. A lower immunostaining of ER (p=0.02) and PR (p=0.03) was found in women with LNM compared with those without. Women were correctly classified by the model in 87% of cases; among the 56 women without LNM that were predicted, 48 (86%) had no LNM at final histology. Among the 12 women with LNM predicted, 11 (92%) had LNM at final histology.

Conclusions: Our results show that lymph node status can be predicted with a relatively high accuracy in women with low- or intermediate-risk EC. This can help physicians to better adapt surgical staging and adjuvant therapies.