原发性肺平滑肌肉瘤罕见,我院遇到1例,现报告如下。患者男性,51岁。咳嗽,咳血痰半年,胸闷1月,于1986年5月20日入院。曾在某医院诊为肺结核,经抗痨治疗无效。有30年吸烟史。体检一般情况好。左肺呼吸音稍减弱。胸片见左肺门下方约2.5×2cm圆形阴影,密度均匀一致,边缘尚清楚。诊断左肺癌。于5月29日行左上叶肺切除术。病理检查肺组织一叶,9.5×7×3.5cm,在肺门支气管旁0.5cm肺组织内可见3.0×2.5×2.0cm肿物,似有包膜,边缘整齐,分界清楚,切面灰红,鱼肉状,质脆,部分区域呈褐色,肿物与支气管不通连。镜下见瘤组织血管丰富,部分区域呈海绵状。瘤细胞围绕血管密集弥漫分布,界限不清,胞浆红染,核呈圆形,卵圆形及梭形,染色质粗颗粒状,核异型性明显。有的区域粘液变性和钙 Primary pulmonary leiomyosarcoma is rare. One case was encountered in our hospital. The report is as follows. The patient male is 51 years old. Cough, hemoptysis and hemorrhage for six months, chest tightness in January, admitted to hospital on May 20, 1986. He had been diagnosed as tuberculosis in a hospital and was not treated with anticonvulsants. There is a history of smoking for 30 years. Physical examination is generally good. Left lung breath sounds slightly weakened. The chest radiograph showed a round shadow of about 2.5 x 2 cm below the left hilum, and the density was uniform and the edges were clear. Diagnosis of left lung cancer. The upper left lung resection was performed on May 29th. Pathological examination of a lung tissue, 9.5 × 7 × 3.5cm, in the 0.5cm lung tissue near the hilar bronchus 3.0 × 2.5 × 2.0cm visible tumor, there seems to be coated, neat edges, clear boundaries, cut gray, fish Shape, crisp, brown in some areas, tumor and bronchi are not connected. Under the microscope, the tumor tissue was rich in blood vessels, and some areas were spongy. The tumor cells were dense and diffusely distributed around the blood vessels, the boundaries were unclear, the cytoplasm was red-stained, the nucleus was round, oval and fusiform, the chromatin was coarse and granular, and the nuclear heteromorphism was obvious. Some areas of mucous degeneration and calcium