Multinucleate cell angiohistiocytoma versus symplastic hemangioma - diagnostic dilemma

Symplastic hemangioma (SH) represents degenerative changes occurring in preexisting hemangioma that can mimic sarcomas and pseudosarcomas. Around eight cases of SH have been reported so far in the literature indicating its rare presentation. On the other hand, multinucleate cell angiohistiocytoma (MCAH) is believed to be a reactive inflammatory process rather than a true neoplastic process. Around 80 cases of MCAH have been reported so far. Both these entities share common histopathological features such as the presence of vascular channels, bizarre cells, inflammatory stroma, and multinucleate giant cells making them to masquerade sarcoma. Hereby, we report a case of a tiny swelling over the dorsum of hand in a 30-year-old female, with a clinical diagnosis of hemangioma. The histopathological examination revealed poorly circumscribed vascular lesion with bizarre cells, multinucleated giant cells scattered against the dense inflammatory background. We considered differential diagnoses of MCAH, SH, and dermatofibroma. We also considered malignancies in differential diagnoses such as hemangioendothelioma, liposarcoma, and metastatic nodule due to the presence of bizarre cells. This case report reemphasizes the presence of atypical histological features that represent degenerative changes occurring in benign tumors which can masquerade malignancies. We discuss the histological features that will help to differentiate SH and MCAH.