Angiosarcoma of the head and neck: A clinicopathologic study with special emphasis on diagnostic pitfalls

Angiosarcoma (AS) is a rare malignant vascular tumor that phenotypically and functionally recapitulate normal endothelium. They constitute approximately 2-4% of soft tissue sarcomas. We present 36 cases of head and neck AS diagnosed for 11 years at a tertiary care hospital in South India to analyze the clinical, pathological, and immunophenotypic profiles with special emphasis on their differential diagnoses and diagnostic pitfalls.

Head and neck AS diagnosed from January 2006 to December 2017 were included. Clinical characteristics, treatment received, and follow-up data were obtained from electronic medical records. Hematoxylin and eosin (H&E)-stained slides and immunohistochemistry (IHC) slides were reviewed, and the histomorphological features, immunohistochemical staining, and their utility in resolving differential diagnosis were assessed.

Twenty-two females and 14 males were diagnosed with head and neck AS in the study period. Histomorphological patterns observed were mixed vasoformative and solid ( n = 22), pure vasoformative ( n = 13), and pure solid ( n = 1). Neoplastic cells showed epithelioid, spindly, signet cell-like, clear cell, and rhabdoid morphology. CD31 was positive in 100% of cases, and CD34 was positive in 40% of cases. Differential diagnoses included melanoma, rhabdomyosarcoma, and large-cell lymphoma. Surgery, radiotherapy, and chemotherapy were the treatment modalities used. Twelve patients developed local recurrence, and 12 patients developed metastasis on follow-up. Twenty-five patients died of disease, on an average of 24 months after diagnosis.

Head and neck AS pose a significant diagnostic challenge due to their broad morphologic spectrum. Proper clinicopathologic correlation is necessary to avoid misdiagnosis.