Neuroendocrine tumors of the female reproductive tract are a heterogeneous group of neoplasms that display various histologic findings and biologic behaviors. In this review, the classification and clinicopathologic characteristics of neuroendocrine tumors of the female reproductive tract are described. Differential diagnoses are discussed, especially for non-neuroendocrine tumors showing high-grade nuclei with neuroendocrine differentiation. This review also discusses recent advances in our pathogenetic understanding of these disorders.

Hong JH, et al. J Gynecol Oncol. 2022 Jan;33:e29. https://doi.org/10.3802/jgo.2022.33.e29

Hong JH, et al. J Gynecol Oncol. 2022 Dec;34:e18. https://doi.org/10.3802/jgo.2023.34.e18

To evaluate the association between mismatch repair (MMR) protein expression and clinico-pathologic outcomes in patients with endometrioid endometrial cancer (EC). A retrospective review of the clinico-pathologic outcomes was performed on patients who were diagnosed with EC and had results of MMR protein immunohistochemistry. MMR-deficient (MMR-d) was defined as absence of expression in any of the 4 MMR proteins (MLH1, MSH2, MSH6, and PMS2). Demographics, pathologic variables, and survival outcomes were compared according to the MMR status. A total of 193 EC patients with available MMR expression data were included, of whom 163 patients had endometrioid type EC. Overall, 44 patients (27.0%) were classified as MMR-d. Compared with MMR-proficient (MMR-p) group, MMR-d group was associated with more frequent lymphovascular space invasion (LVSI, p = 0.001). MMR-d was also related with higher risk of lymph node (LN) metastasis in endometrioid type EC (p = 0.008), especially para-aortic LN metastasis. During the median follow-up period of 19.1 months (1-44.5), MMR-d group, especially MLH1/PMS2 subgroup, showed a tendency of reduced PFS (p = 0.036 and p = 0.008, respectively). On Cox regression analysis, however, LN metastasis remained as the only independent risk factor for PFS (p = 0.004) in endometrioid EC, and MLH1/PMS2 loss showed a marginally significant association (p = 0.054). Our findings of the associations between MMR deficiency and poor prognostic factors, such as LVSI and LN metastasis, may suggest the prognostic value of MMR status in EC and need further prospective validation studies.

Chun YK, et al. J Korean Med Sci. 2010 Jun;25(6):970-973. http://dx.doi.org/10.3346/jkms.2010.25.6.970

This study aimed to evaluate the efficacy of the 2020 European Society of Gynecological Oncology/European Society for Radiotherapy and Oncology/European Society of Pathology (ESGO/ESTRO/ESP) guidelines for endometrial cancer (EC). Additionally, a novel risk category incorporating clinicopathological and molecular factors was introduced. The predictive value of this new category for recurrence and survival in Korean patients with EC was assessed, and comparisons were made with the 2013 and 2016 European Society of Medical Oncology (ESMO) risk classifications. Patients with EC were categorized into the POLE-mutated (POLEmut), mismatch repair-deficient (MMRd), p53-aberrant (P53abn), and nonspecific molecular profile (NSMP) subtypes. Recurrence, survival, and adjuvant therapy were assessed according to each classification. Notably, patients with the POLEmut subtype showed no relapse, while patients with the P53abn subtype exhibited higher recurrence (31.8%) and mortality rates (31.8%). Regarding adjuvant therapy, 33.3% of low-risk patients were overtreated according to the 2020 ESGO/ESTRO/ESP guidelines. Overall and progression-free survival differed significantly across molecular classifications, with the POLEmut subtype showing the best and the P53abn subtype showing the worst outcomes. The 2020 ESGO molecular classification system demonstrated practical utility and significantly influenced survival outcomes. Immunohistochemistry for TP53 and MMR, along with POLE sequencing, facilitated substantial patient reclassification, underscoring the clinical relevance of molecular risk categories in EC management.