Background: The case of a male patient, 68, who presented with one week’s history of cough, dyspnoe and hemosputum. Chest X-ray showed a shadow near the hilum of the right-sided lung. Furthtermore, CT scan of the thorax demonstrated a right middle lobe mass with signs of peripheral obstructive pneumonitis. Bronchoscopy revealed a stenosis of the right middle lobe, of which biopsy material was taken for microscopic examination.
Methods: The bioptic material consisted of seven pale-white tissue specimens, 0.2–0.3 cm in greatest diameter.
Results: The material contained blood clots, fibrin, and mucin, as well as superficial mucosal specimens. The submucosa of the latter was infiltrated by mainly medium-sized, neoplastic cells with crush artifacts and degenerative changes. These cells showed increased pleomorphy and atypia, with enlarged, abnormal nuclei and distinct nucleoli. Among the immunohistochemical stains, Vimentin, Desmin and Calponin were positively expressed, a fact that implies the mesenchymal origin of the neoplasm. On the other hand, SMA, Caldesmon, MyOD1, CD56, AE1/AE3, CK8/18, CK7, CK5/6, TTF-1, p63, CD45, HMB-45, S-100 and CD34 were negative. The proliferation marker (Ki67) was expressed in 80% of the neoplastic cells. Given the above findings, the diagnosis referred to a mesenchymal neoplasm (sarcoma) of myogenic origin, with high-grade malignancy. The patient received a platinum and taxane chemotherapy.
Conclusions: The microscopic examination of bronchoscopy biopsy material usually leads to the diagnosis of a variety of pulmonary diseases. Immunohistochemistry has significantly expanded the pathologist’s diagnostic abilities. However, in some cases, due to the rarity of the disease or the inappropriacy of the biopsy material, there can only be a rough estimation of the origin of the malignant neoplasm. In this case, the differential diagnosis would include, among else, a leiomyosarcoma, a synovial sarcoma, a fibrosarcoma, the spindle-cell variant of squamous cell carcinoma and a metastatic carcinoma.
