Diffuse pulmonary carcinomatous embolization: a rare and fatal manifestation of ovarian cancer.

A 44-year-old female presented with dyspnea and lethal respiratory failure secondary to pulmonary embolic carcinomatosis as a manifestation of ovarian serous cystadenocarcinoma. Diffuse involvement of pulmonary arterioles and muscular arteries ranging from 30 to 950 microns in diameter was observed in conjunction with slight dilatation of pulmonary arteries. Vascular intraluminal changes included the presence of free clusters of malignant cells, superimposed thrombosis, varying degrees of eccentric fibromyxoid intimal proliferation with entrapped malignant cells, and luminal obliteration with neovascularization. The pathobiological aspects of this unique manifestation of ovarian neoplasia are discussed.