MELF invasion in endometrial cancer as a risk factor for lymph node metastasis.

Kitty Pavlakis (1) , Irini Messini (1) , Theodoros Panoskaltsis (2) , Thomas Vrekoussis (3) , Dimitris Chrysanthakis (1) , Petros Yiannou (1) , Zannis Voulgaris (4)

1 Pathology Department
2 Gynecological Oncology
3 Pathology
4 Gynecological Oncology

Aim: To investigate whether the microcystic, elongated and fragmented (MELF) pattern of myometrial invasion encountered in certain endometrioid endometrial carcinomas can be considered as a risk factor for lymph node metastasis. Materials and Methods: 351 cases of total abdominal hysterectomy and bilateral salpingo-oophorectomy with/without lymphadenectomy or lymph node sampling, performed for endometrioid endometrial adenocarcinoma were enrolled in the study. The existence of MELF invasion, vascular invasion, fibromyxoid stromal reaction and lymph node metastasis were recorded. Immunohistochemistry for endothelial and epithelial markers was performed on selected cases. Results: MELF invasion was identified in 20 (10.81%) and 13 cases (13.13%) treated without and with lymphadenectomy respectively. All of these cases were either well or moderately differentiated carcinomas, stage IA to II (without considering lymph node status). Positive lymph nodes were detected in 7/13 MELF positive (53.84%) and in 6/86 MELF negative cases (6.97%) This observation was statistically significant. Out of the 7 MELF positive tumours with lymph node metastasis, 3 cases exhibited intravascular tumour emboli while 4 showed a fibromyxoid stromal reaction. Conclusion: MELF pattern invasion was found to be statistically related to lymph node metastasis. Nevertheless, further studies are needed in order to evaluate the clinical significance of this observation.

Mots clés: Medicine

Kitty Pavlakis, Irini Messini, Theodoros Panoskaltsis, Thomas Vrekoussis, Dimitris Chrysanthakis, et al.. MELF invasion in endometrial cancer as a risk factor for lymph node metastasis.. Histopathology, 2011, 58 (5), pp.739. ⟨10.1111/j.1365-2559.2011.03801.x⟩. ⟨hal-00626293⟩