Imprint cytology of pulmonary artery sarcoma

—A case report—

Abstract

Background : Pulmonary artery sarcoma is rare, and diagnosis before surgery is difficult. The characteristic cytologic appearances have not been described yet.
Case : A man in the fifties was admitted to our hospital with a persistent cough. Computed tomographic examination revealed a pulmonary nodule in the lower left lung field. The lesion was suspected to be a primary pulmonary carcinoma and was resected with a left lower lobectomy. Imprint cytologic smears obtained from the resected specimen revealed clusters of small and uniform epithelioid cells, and small tumor cells with polygonal and thick cytoplasm. The nuclei of the cells were round and localized. The nuclei frequently showed irregularity, but without any conspicuous atypia. Intracytoplasmic and/or nuclear inclusions were prominent. No mitosis was seen. We therefore diagnosed them as atypical columnar cells, uncertain as to whether they were benign or malignant. Histologically, the tumor was diagnosed as an artery sarcoma combining the above data with an immunohistochemical examination.
Conclusion : Although the cytologic appearance of pulmonary artery sarcoma is similar to that of pulmonary adenocarcinoma, focusing on cytologic findings such as nuclear features and inclusion body structures may allow them to be distinguished.