Rhabdomyomatous Mesenchymal Hamartoma: An Acquired Plaque-Type Variant Case Report

Area of Science:

• Dermatology
• Pathology
• Oncology

Background:

• Rhabdomyomatous Mesenchymal Hamartoma (RMH) is a rare, benign tumor typically congenital, affecting the dermis and subcutaneous tissue.
• Lesions comprise mature skeletal muscle and mesenchymal-derived tissue, often presenting as midline head/neck masses in children.
• Adult presentations are less common, with varied clinical and histologic characteristics.

Purpose of the Study:

• To present a case of Rhabdomyomatous Mesenchymal Hamartoma (RMH) in an adult patient.
• To describe the clinical presentation and histologic findings of this uncommon variant.
• To discuss the unique histologic properties observed in this acquired, plaque-type RMH.

Main Methods:

• Clinical case presentation.
• Histologic evaluation of the lesion.
• Review of relevant literature on RMH in adults.

Main Results:

• An adult patient presented with an acquired, plaque-type Rhabdomyomatous Mesenchymal Hamartoma on the chin.
• Histologic examination revealed unique properties distinct from typical congenital RMH.
• The lesion demonstrated a disordered collection of mature skeletal muscle and mesenchymal elements.

Conclusions:

• This case highlights an uncommon variant of acquired Rhabdomyomatous Mesenchymal Hamartoma in an adult.
• The unique histologic features underscore the diverse presentations of RMH.
• Further research into adult RMH variants may refine diagnostic and therapeutic approaches.