The clinical presentation, imaging, and histology are consistent with angiosarcoma, which is a rare, aggressive malignancy that grows insidiously.
The clinical appearance of the tumor in the hand often has central necrosis that is manifested with overlying skin changes. Radiographs often reveal eccentric, purely lytic, metaphyseal and diaphyseal lesions, with no visible matrix mineralization. The histology often shows vascular channels with neoplastic cells that have abundant eosinophilic cytoplasm and large nuclei with mitotic figures. CD31 is a sensitive marker for angiosarcoma. A wide range of treatments have been proposed including resection, forequarter amputation, adjunctive radiation, and chemotherapy depending on the extent, metastasis, and aggressiveness of the lesion.
Vandevender et al offer a Level 5 evidence review on vascular hand tumors. They state that "angiography helps determine the extent of the lesion and may show metastasis" and MR imaging is valuable for evaluating the size and extent of the lesion.
Walsh et al provided an overview of vascular tumors, classifying them into benign, congenital and malignant. Angiosarcomas can arise following irradiation and poly-vinyl chloride exposure.
Vandevender DK, Daley RA. Benign and malignant vascular tumors of the upper extremity. Hand Clin. 1995 May;11(2):161-81. Review.
PMID:7635879 (Link to Abstract)
Walsh JJ 4th, Eady JL. Vascular tumors. Hand Clin. 2004 Aug;20(3):261-8, v-vi
PMID:15275685 (Link to Abstract)