Intravascular pseudolymphomatous angiosarcoma: A new finding potentially mistaken for intravascular lymphoma.

Pseudolymphomatous infiltrates associated with angiosarcoma are a rarely reported phenomenon. Recognition of this reactive process is critical to making an accurate diagnosis, both in diagnosing the angiosarcoma and in avoiding an incorrect diagnosis of lymphoma. Here, we present a novel histopathologic pattern, angiosarcoma with a prominently intravascular atypical lymphoid component, mimicking intravascular T-cell lymphoma. Interestingly, serial biopsies in this case revealed a progressive increase in lymphocyte density and intravascular component over time. Despite prior reports of improved progression-free survival and overall survival of patients with pseudolymphomatous angiosarcoma, this patient showed rapid disease progression.