Dedifferentiated Leiomyosarcoma of the Uterine Corpus with Heterologous Component: Clinicopathological Analysis of Five Consecutive Cases from a Single Institution and Comprehensive Literature Review

Establishment of Two Novel Ovarian Tumor Cell Lines with Characteristics of Mucinous Borderline Tumors or Dedifferentiated Carcinoma-Implications for Tumor Heterogeneity and the Complex Carcinogenesis of Mucinous Tumors

BACKGROUND/OBJECTIVE

Mucinous borderline tumors of the ovary (MBOTs) are characterized by their unique histological features and intermediate malignant potential; however, the factors underlying their molecular carcinogenesis and tumor biology remain largely unknown. Developing cell lines from these tumors presents an ongoing challenge. The purpose of this study is to establish MBOT cell lines and characterize their biological features.

METHODS

Epithelial cells were collected and purified from surgically removed MBOT samples and then stably maintained with an extended life span by overexpressing CyclinD1/CDK4 in combination with human telomerase reverse transcriptase. The characterization of resulting cell lines was defined by morphology, growth kinetics, functional analysis, whole-exome sequencing, and tumorigenicity in mice.

RESULTS

Two independent cell lines, HMucBOT-1 and HMucBOT-2, were successfully established from the tissues of a patient with an MBOT, with the latter showing more aggressive growth capacity. In the patient-derived xenograft model, HMucBOT-1 cells retained the original morphological characteristics of the MBOT, whereas HMucBOT-2 cells displayed a transition to mucinous carcinoma accompanying undifferentiated carcinoma, suggestive of dedifferentiated carcinoma. Genetic analysis of the original tumor sample and HMucBOT-2 cells revealed shared oncogenic mutations. However, KRAS amplification and certain copy number alterations were uniquely observed in the HMucBOT-2 cells.

CONCLUSIONS

The above results indicate that HMucBOT-1 can serve as a preclinical model for investigating the biological behavior of and potential targeted therapies for human MBOTs, with HMucBOT-2 serving as a valuable tool for studying the heterogeneity and genetic diversity of this tumor and explaining the potential causes of treatment failure or relapse.

Editorial on the Special Issue Titled "Pathology and Diagnosis of Gynecologic Diseases-2nd Edition"

The pathology and diagnosis of gynecological diseases encompass many different organs (breasts, uterus, ovaries, salpinx, peritoneum, and placenta) and benign or malignant diseases [...].

Dedifferentiated recurrent liposarcoma of the uterine corpus: A case report and literature review

Liposarcoma of the uterine corpus represents an exceptionally rare tumor, with few cases documented in the literature, underscoring its unique histopathologic characteristics and management challenges. This case describes the clinical management of a 57-year-old patient with well-differentiated liposarcoma of the uterine corpus who presented with a three-month history of abdominal pain and distension. She underwent an abdominal hysterectomy followed by chemotherapy but experienced local recurrence in the mesentery and retroperitoneum after 21 months. Tumor resection was performed again, followed by chemotherapy, but the patient experienced a second recurrence 15 months later, involving the small intestine, vaginal stump, and ureter, with evidence of dedifferentiated liposarcoma. A third surgical resection was carried out without administering chemotherapy and the patient remained asymptomatic at follow-up appointments every 3 months for a year. This case highlights the importance of acknowledging the aggressive nature of recurrent liposarcoma, especially its transition into dedifferentiated liposarcoma, and the need for tailored management strategies.