A mass formed of spindle shaped cells surrounding cleft like spaces situated in the lung. Hyperchromatic and pleomorphic nuclei. Stains for pneumocystis carinii are negative.
The spindle cells stain positively with endothelial markers C34 and factor VIII related antigen. Vimentin is positive. Desmin and SMA are negative.
Comment: The appearances are those of Kaposi’s sarcoma