Title: Adult tongue rhabdomyosarcoma: A rare case report and review of diagnostic and therapeutic challenges
Abstract:
Rhabdomyosarcoma (RMS) is a malignant mesenchymal neoplasm characterized by skeletal muscle differentiation and is predominantly a paediatric malignancy. It represents the most common soft-tissue sarcoma in children; however, its occurrence in adults is rare and often associated with a poorer prognosis. Within the head and neck region, RMS commonly arises in the orbit, nasopharynx, or paranasal sinuses. Primary involvement of the tongue in adults is exceedingly uncommon, creating diagnostic and therapeutic challenges for clinicians in oral and maxillofacial surgery. This report describes a rare case of rhabdomyosarcoma of the tongue in and discusses the clinical, radiological, histopathological, and management considerations relevant to this unusual presentation. A 35-year-old female presented with a firm asymptomatic slow growing mass on the anterior tip of the tongue. Clinical examination revealed a 20mmx10mm distinct palpable lesion on the midline of the tongue, with slightly erythematous overlying mucosa. Initial differential diagnoses included benign muscular tumours, granular cell tumour, minor salivary gland neoplasm, and soft tissue sarcoma. Magnetic resonance imaging demonstrated a well-defined soft-tissue lesion indicative of a minor salivary gland tumour without obvious nodal involvement.
An excisional biopsy followed by histopathological analysis revealed a malignant indolent spindle-shaped Rhabdomyosarcoma with evidence of skeletal muscle differentiation. Immunohistochemical staining showed positivity for desmin, myogenin (sparse), and MyoD1 (extensive), confirming the diagnosis of rhabdomyosarcoma. Further staging investigations excluded distant metastasis. The patient was later referred to a different centre following a multidisciplinary discussion involving oral and maxillofacial surgery, oncology, and pathology teams.
Adult rhabdomyosarcoma of the tongue is extremely rare and may mimic more common benign or malignant oral lesions, leading to potential delays in diagnosis. Early biopsy of suspicious tongue lesions and the use of immunohistochemistry are essential for accurate diagnosis. Due to the rarity of this tumour in adults, optimal treatment strategies are not well standardized, but current evidence supports aggressive multimodal therapy combining surgery, chemotherapy, and radiotherapy to improve outcomes. This case highlights the importance of considering rhabdomyosarcoma in the differential diagnosis of unusual tongue masses in adults and underscores the need for early multidisciplinary management to optimize prognosis.
