Granular Cell Myoblastoma, also known as Granular Cell Tumor, is a rare benign tumor that mainly affects the skin and subcutaneous tissues, but can occasionally occur in other sites of the body, such as the oral cavity, breast, and internal organs. It is characterized by the presence of granular cells, which are large, round or oval cells containing numerous granules in their cytoplasm. These granules stain positively for certain substances, such as S-100 protein and periodic acid-Schiff (PAS).
Clinically, Granular Cell Myoblastoma typically presents as a painless, slow-growing, solitary, or occasionally multiple nodules ranging in size from a few millimeters to several centimeters. The tumor is usually well-defined, firm, and non-tender upon palpation. Granular Cell Myoblastoma commonly occurs in adults, with a slight female predominance.
The exact cause of Granular Cell Myoblastoma is still uncertain, although various theories suggest a potential origin from muscle cells, Schwann cells, or fibroblasts. While most cases of Granular Cell Myoblastoma are benign, rare malignant cases have been reported. Therefore, it is crucial for an accurate diagnosis, which is usually achieved through a combination of clinical examination, imaging tests (such as ultrasonography or magnetic resonance imaging), and definitive histological examination of tissue samples obtained through biopsy or surgical removal.
Treatment options for Granular Cell Myoblastoma primarily involve surgical excision. Complete removal is usually curative, with a low recurrence rate observed. However, regular follow-up examinations are recommended to monitor for any potential recurrence or malignant transformation. In cases where complete excision is not feasible, alternative treatments such as radiation therapy or intralesional
