Multifocal recurrent adult rhabdomyoma

Abstract

The clinical and morphologic features of a recurrent, multifocal, adult, extracardiac rhabdomyoma are reported. This benign skeletal muscle neoplasm is composed of large round to polyhedral cells containing cross striations. The ultrastructural features consist of hypertrophic Z bands, intranuclear inclusions, and numerous mitochondria with linear, intracristal inclusions. The low thymidine labeling index and long potential doubling time correspond wi th the length of time for clinical recurrence.

Rhabdomyoma of the head and neck: morphology and differential diagnosis

“…AR grows most frequently as a solitary mass (about 70%), but may be multinodular with discrete nodules in the same area (about 25%) or, rarely, even multicentric (about 5%) [6,19]. Due to high local recurrence rate (up to 42%), complete excision is recommended [6,15,[18][19][20][21]. By contrast, malignant transformation has not been described.…”

Mediastinal rhabdomyoma: case report and review of the literature

“…There have been reported cases with a larger size [5,9] as Histologically, the tumor is composed of well-demarcated lobules that consist of closely packed, large polygonal cells and scant stroma containing thin-walled vascular channels [1,6,8,10,16,17]. The tumor cells have small round centrally or peripherally located nuclei with prominent nucleoli and abundant eosinophilic, granular or peripherally vacuolated cytoplasm [1,7,11,16,17]. The peripherally located vacuoles are a result of the removal of intracellular glycogen by the fixative.…”

“…The peripherally located vacuoles are a result of the removal of intracellular glycogen by the fixative. When they are surrounded by residual radially oriented cytoplasm, they impart a spider web appearance to the cell [7,10,16]. Cytoplasmic cross-striations and crystal-like structures can be found focally in hematoxylin-eosin stained sections in most but not all of the cases.…”

“…The cytoplasm is rich in glycogen which gives the Periodic-Acid Schiff reaction positive but sensitive to prior diastase treatment [5,9,7,15]. Mitoses are absent [1,10,16]. Foci of inflammation and necrosis with reactive nuclear features can rarely be seen [10].…”

“…However, recurrences have been reported to happen after 1 month to 35 years [9][10][11]16] and are probably due to incomplete resection of the primary tumor. Uncontrolled focal growth, metastases, or death due to the neoplasm has not been reported [11].…”