A Case of “Collision” of Squamous Cell and Small Cell Carcinoma of the Lung

A case of “collision” lung cancer was reported.An abnormal shadow was pointed out in left S6 in a 70-year-old man.One month later, a second tumor-shadow appeared near the first coin lesion and the two tumor-shadows had developed into a fused tumor during the period of followup. Specimens from percutaneous biopsy showed class V Papanicolaou. Left lower lobectomy with mediastinal lymph node dissection was performed. From the features of chest roentogenographs and post-operative histology, this tumor was considered to be a case of collision of small cell and squamous cell carcinoma.