[1231] Number of Involved Lymphatic Vessels and Their Distance from Tumor Are Independent Prognostic Factors of Lymph Node Metastases in Low Grade Endometrial Adenocarcinoma. A Multi-Institutional Study
Delia Perez Montiel, Elizabeth Dierksen Euscher, Andres Roma, Elizabeth J Moschiano, Rouba Ali-Fehmi, Elizabeth F Frauenhoffer, Insun Kim, Bojana Djordjevic, Denise A Barbuto, Sun Rang Hong, Anais Malpica, Elvio G Silva. Instituto Nacional de Cancerologia, Mexico City, Mexico; Multi Institutional Study, Los Angeles
Background: Metastasis to lymph node in low-grade endometrial adenocarcinoma (LGEC) are uncommon. Clinical stage is the most important prognostic factor in predicting nodal disease regardless of histological grade. The aim of this study was to investigate whether histological features exist that can predict lymph node involvement.
Design: This is a multi institutional case-control study where 153 patients with LGEC and nodal disease were compared to 336 controls with negative lymph nodes. Studied variables included size and appearance of tumor, depth of myometrial infiltration, cervical stromal and or lower uterine segment involvement (LUS), stromal reaction, intratumoral necrosis, LVI (divided as 0, 1 vessel, 2-5 vessels and more than 5 vessels), distance to LVI (adjacent to neoplasm and deeper than invasive front of tumor). Difference between mean estimates were evaluated by the student´s-T, Chi-square or Fisher exact tests. Multivariate analysis was performed using logistic regression model. P<0.05 was considered statistically significant.
Results: Mean age in the case group was of 58.2 years vs 61 in controls (p=0.010). Average tumor size 5.4 cm vs 4.2 cm (p=0.001), myometrial invasion 58% vs 35% (p=0.0001).
| Cases with LNM (n=153) | Control cases (n=336) | P | |
| LVI (more than 5 foci) | 39% | 9% | 0.0001 |
| Distant LVI | 28% | 6% | 0.0001 |
| Necrosis | 60% | 35% | 0.0001 |
| Stromal reaction | 84% | 55% | 0.0002 |
| Stromal cervical invasion | 33% | 9% | 0.0001 |
| LUS involvement | 60% | 37% | 0.0002 |