Embryonal Rhabdomyosarcoma of the Uterine Cervix: A Clinicopathologic Study of 94 Cases Emphasizing Issues in Differential Diagnosis Staging, and Prognostic Factors

Pleomorphic rhabdomyosarcoma of the vagina: A case report

BACKGROUND

Rhabdomyosarcoma (RMS) of the vagina in postmenopausal women is an extremely rare malignant tumor that was originally described as a unique group of soft tissue sarcomas originating from primitive mesenchymal cells. It was first reported in postmenopausal women in 1970, and fewer than 50 postmenopausal patients have been reported to date.

CASE SUMMARY

A 68-year-old multiparous female was admitted to the hospital on October 11, 2023, with the chief complaint of a mass causing vaginal prolapse with incomplete urination that had persisted for 4 months. The vaginal mass was approximately the size of a pigeon egg; after lying down, the vaginal mass retracted. Complete resection was performed, and vaginal pleomorphic RMS was diagnosed based on pathology and immunohistochemical staining features. The patient is currently undergoing chemotherapy. The present study also reviewed the clinical, histological, and immunohistochemical features and latest treatment recommendations for vaginal RMS. Any abnormal vaginal mass should be promptly investigated through pelvic examination and appropriate imaging. The current initial treatment for vaginal RMS is biopsy and primary chemotherapy.

CONCLUSION

When surgery is planned for vaginal RMS, an organ-preserving approach should be considered.

Rhabdomyosarcoma: Updates on classification and the necessity of molecular testing beyond immunohistochemistry

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children and adolescents under the age of 20. The current World Health Organization (WHO) classification for soft tissue and bone tumors recognizes 4 distinct subtypes of RMS based on clinicopathological and molecular genetic features: embryonal, alveolar, spindle cell/sclerosing and pleomorphic subtypes. However, with the increased use of molecular techniques, the classification of rhabdomyosarcoma has been evolving rapidly. New subtypes such as osseus RMS harboring TFCP2/NCOA2 fusions or RMS arising in inflammatory rhabdomyoblastic tumor have been emerging within the last decade, adding to the complexity of diagnosing skeletal muscle tumors. This review article provides an overview of classically recognized distinctive subtypes as well as new, evolving subtypes and discusses important morphologic, immunophenotypic and molecular genetic features of each subtype including recommendations for a diagnostic approach of malignant skeletal muscle neoplasms.

The "Other" Uterine Mesenchymal Neoplasms: Recent Developments and Emerging Entities

Uterine mesenchymal neoplasms are a challenging group of tumors that often show overlapping morphologic features and immunohistochemical profiles. The increasing use of molecular testing in these tumors has enabled a better appreciation of their pathobiology, resulting in a wave of emerging neoplasms and improved characterization of ones previously considered exceptionally rare. Identification of specific molecular alterations has permitted targeted therapy options in tumors that were typically unresponsive to conventional therapies, as well as recognition that a subset can have a hereditary basis. This review will discuss the more "common" of the uncommon uterine mesenchymal neoplasms, including inflammatory myofibroblastic tumor, perivascular epithelioid cell tumor, uterine tumor resembling ovarian sex cord tumor, and embryonal rhabdomyosarcoma. This will be followed by an overview of emerging entities, including NTRK-rearranged uterine sarcoma, SMARCA4-deficient uterine sarcoma, KAT6B/A::KANSL1 fusion uterine sarcoma, and MEIS1::NCOA2/1 fusion sarcoma.

Patient-derived organoids facilitating individual therapy in an adolescent with embryonal rhabdomyosarcoma of the cervix: a case report and literature review

Rhabdomyosarcoma (RMS) is a highly aggressive pediatric neoplasm that originates from striated muscle or undifferentiated mesenchymal cells. Based on its histopathological characteristics, the World Health Organization categorizes RMS into four distinct subtypes: embryonal RMS, alveolar RMS, pleomorphic RMS, and sclerosing/spindle cell RMS. Embryonal RMS represents the predominant subtype and primarily manifests in the head and neck region, with the genitourinary system being the subsequent most frequent site of occurrence. Embryonal rhabdomyosarcoma of the cervix (cERMS) is more insidious in the reproductive tract, and there is still a lack of consensus on its treatment. Patient-derived organoids (PDOs) are being prioritized for use in guiding personalized medicine. The application of PDOs to test the sensitivity of chemotherapy drugs in patients with cERMS has rarely been reported. In this case report, we delineate the presentation and diagnosis of a 16-year-old adolescent with cERMS, emphasizing the utilization of PDOs in the management of this infrequent neoplasm. We intend to elucidate the diagnostic and therapeutic processes associated with cERMS by referencing previously reported literature on this infrequent tumor, aiming to offer a foundation for clinical practice.

Genomic characterization of DICER1-associated neoplasms uncovers molecular classes

DICER1 syndrome is a tumor predisposition syndrome that is associated with up to 30 different neoplastic lesions, usually affecting children and adolescents. Here we identify a group of mesenchymal tumors which is highly associated with DICER1 syndrome, and molecularly distinct from other DICER1-associated tumors. This group of DICER1-associated mesenchymal tumors encompasses multiple well-established clinicopathological tumor entities and can be further divided into three clinically meaningful classes designated "low-grade mesenchymal tumor with DICER1 alteration" (LGMT DICER1), "sarcoma with DICER1 alteration" (SARC DICER1), and primary intracranial sarcoma with DICER1 alteration (PIS DICER1). Our study not only provides a combined approach to classify DICER1-associated neoplasms for improved clinical management but also suggests a role for global hypomethylation and other recurrent molecular events in sarcomatous differentiation in mesenchymal tumors with DICER1 alteration. Our results will facilitate future investigations into prognostication and therapeutic approaches for affected patients.