Clinicopathological and molecular characteristics of endometrial neuroendocrine carcinomas reveal preexisting endometrial carcinoma origin

Triple synchronous primary cancers comprising large cell neuroendocrine carcinoma of the lower uterine segment and endometrioid carcinomas of the uterine corpus and the right ovary-a rare combination: A case report

We report a rare case of triple primary cancers in a 52-year-old woman who presented with abdominal pain and fever. Diagnostic imaging and subsequent histopathological evaluation revealed independent primary endometrioid carcinomas of the ovary and uterine corpus proper (UC), as well as large cell neuroendocrine carcinoma (LCNEC) originating from the lower uterine segment (LUS). Surgical resection was performed, followed by adjuvant chemotherapy (irinotecan and cisplatin). The patient demonstrated no recurrence at the 10-month follow-up. This case highlights the importance of accurate pathological differentiation, as prognosis and treatment depend on distinguishing independent primary tumors from metastatic lesions. This rare case of triple synchronous malignancies emphasizes the need for a multidisciplinary approach to ensure precise diagnosis and optimal management. Comprehensive molecular studies and advanced imaging techniques may further improve outcomes in such complex cases.

Whole exome sequencing identifies common mutational landscape of cervix and endometrium small cell neuroendocrine carcinoma

Background

Primary small cell neuroendocrine carcinomas of the cervix and endometrium are rare gynecological malignancies with limited treatment options. This study aimed to improve the understanding of the carcinogenesis process and identify potential therapeutic targets for these two tumor types by constructing the mutational landscape at the whole exome level.

Methods

Primary tumor tissues and their matched blood samples were obtained from 10 patients with small cell cervical neuroendocrine carcinoma (NECC) and five patients with small cell endometrial neuroendocrine carcinoma (NECE). Whole exome sequencing was performed to construct the somatic mutation profiles. Mutational signature and recurrent mutated gene analysis were used to identify tumor subtypes and common carcinogenesis processes.

Results

Based on the burden of different mutational signatures, the NECCs in this work can be divided into two subtypes, including the mismatch repair deficiency like (dMMR-like) type (4/10) and the high spontaneous deamination type (6/10). Components of the PI3K/AKT signaling and RAS signaling were exclusively mutated in these two subtypes, respectively. The integration of human papillomavirus made a limited contribution to tumorigenesis in NECC (20%). The dysfunction of the mismatch repair system and microsatellite instability are the major features of NECE. PI3K/AKT, JAK/STAT signaling, and chromatin remodeling activity were the common mutated pathways in NECE. PIK3CA, WNK2, and KMT2B underwent mutations in both the dMMR-like subtype of NECC (50% - 75%) and in NECE (60% - 80%) specimens, while exhibiting infrequent mutational occurrences in publicly available data pertaining to neuroendocrine carcinomas of the lung or bladder (< 10%).

Conclusion

We identified the two subtypes of NECC with distinct mutated pathways and potential therapy targets. The dMMR-like type NECC and NECE may share a similar carcinogenesis process that include dysfunction of PI3K/AKT signaling, cell cycle, antiapoptotic processes, and chromatin remodeling activity.

Pilomatrix-like High-Grade Endometrioid Carcinoma of the Ovary: Case Report, Literature Review, and Differential Diagnosis

Pilomatrix-like high-grade endometrioid carcinoma (PiMHEC) has recently been described as an aggressive variant of endometrial carcinoma. Herein, we described a case of ovarian PiMHEC, comparing it to endometrial PiMHEC and assessing previously published cases of putative ovarian PiMHEC. A 65-year-old woman underwent hysterectomy for an ovarian tumor characterized by solid nests of basaloid cells with prominent ghost cell keratinization. Immunohistochemistry showed nuclear β-catenin and CDX2 expression and loss of estrogen and progesterone receptors and PAX8. These features were consistently observed in all previously published cases and may represent diagnostic criteria of PiMHEC. Other frequent features were geographic necrosis and a low-grade endometrioid component. CK7, neuroendocrine, and basal/squamous markers were inconsistently expressed. All cases with available follow-up showed poor prognosis. PiMHEC should be distinguished from mimickers, such as high-grade endometrioid carcinoma with geographic necrosis, low-grade endometrioid carcinoma with ghost cell keratinization, and undifferentiated/dedifferentiated carcinoma. In conclusion, PiMHEC can also occur in the ovary and shows several consistent clinical, morphological, and immunophenotypical features. These features support that PiMHEC is a distinct entity requiring an aggressive management.