Track
Case ReportsAbstract
Introduction: Intramuscular capillary-type hemangioma (ICTH) is a rare benign vascular anomaly involving skeletal muscle. It presents as a slowly growing, painful intramuscular mass, often in younger individuals. The ISSVA renamed it "Intramuscular Fast-Flow Vascular Anomaly" (IFVA) due to possible associations with somatic MAP2K1 and KRAS mutations, with Goss et al. detecting such mutations in 6 of 8 ICTH specimens. A French multicenter study of 66 cases found only 7 with features overlapping arteriovenous malformations; no mutations were found in the single case tested. Further studies are needed to clarify these molecular findings. Case Summary: A 62-year-old Cuban woman presented with a year-long, slowly enlarging, non-tender, 0.9 × 0.9 cm lesion on her left forehead without trauma. Excisional biopsy revealed lobules of capillary-like vessels lined by plump endothelial cells infiltrating skeletal muscle and mixed with adipose tissue. No mitotic activity or atypia was seen. The lesion was diagnosed as intramuscular capillary-type hemangioma. The patient recovered well with minimal scarring. Conclusion: ICTH’s rarity often leads to missed preoperative diagnosis. Differential diagnoses include intramuscular lipoma, angiolipoma, and angiosarcoma. Imaging like CT or MRI can aid diagnosis but is typically not needed for small superficial lesions. Complete excision is preferred due to high local recurrence (30–50%). While mainly affecting younger patients, this case shows occurrence in older individuals. Further research is needed to understand its genetics and validate its classification and nomenclature.