Chronic Expanding Hematoma with a t(11;19)(q13;q13) Chromosomal Translocation.

ABSTRACT

BACKGROUND/AIM: Chronic expanding hematoma is defined as a hematoma that gradually expands over 1 month or longer, is without neoplastic features on histological sections, and does not occur in the setting of coagulopathy. The pathogenetic mechanism behind its development is unknown, nor is anything known about its genetic features. CASE REPORT A 49-year-old man noted a tender lump close to the right femoral trochanter. Examination of a core needle biopsy showed a fibrous capsule with fibrinoid material on one side. The patient underwent surgery with removal of a cystic, encapsulated structure with central bleeding and proliferating vessels in the fibrous capsule. The reactive fibroblasts were without any sign of atypia. Genetic analyses were performed on this chronic expanding hematoma. RESULTS: G-Banding analysis of short-term cultured cells from the chronic expanding hematoma yielded a karyotype with a single clonal chromosome abnormality 46,XY,t(11;19)(q13;q13)[8]/46,XY[10]. RNA sequencing and examination of the sequencing data using five different programs did not identify fusion genes related to the translocation. CONCLUSION: The acquired translocation t(11;19)(q13;q13) suggested that chronic expanding hematoma is a neoplastic lesion. Since the translocation did not lead to any fusion genes, one can speculate that it causes deregulation of gene expression.