Dear Editor,
We read with a great deal of interest the article entitled “Prognostic Significance of Microcystic Elongated and Fragmanted (MELF) Myometrial Invasion Pattern: A Retrospective Study” by Okcu et al.1.
In their cohort, the MELF pattern was observed in 29.8% of the patients, and it was significantly related to lymphovascular space invasion (LVSI), stage, infiltrative pattern, and necrosis. No significant relation was identified with overall or disease-free survival rates. The authors concluded that additional sectioning and immunohistochemical (IHC) analysis should be performed to the excised lymph nodes to identify micrometastases as MELF associated with LVSI and lymph node metastases.
Recently, Qi et al.2 demonstrated that the combination of MELF and tumor budding is a histological marker associated with tumor aggressiveness and can be an independent predictor of adverse outcomes. Moreover, Tahara et al.3 reported a strong expression of programed death-ligand 1 (PD-L1) in the invasive front of the MELF pattern and concluded that programed cell death protein 1/PD-L1 immunotherapy demonstrated significant therapeutic effect on the management of patients with endometrial cancer and grade 1 MELF. Furthermore, Rabe et al.4 claimed that cytokeratin IHC staining could detect malignant cells in the sentinel lymph nodes of patients with endometrial cancer and MELF.
Finally, in a large cohort study, He et al.5 revealed that participants with POLE-mutated tumors and MELF pattern invasion had a 15.1-fold increase in tumor recurrence or progression risk than POLE-wild type tumors. Once again, we thank the authors for their excellent study.
