A 65-year-old man with limited disease-small cell lung cancer was treated with concurrent chemoradiotherapy which resulted in a partial response. He further received high-dose chemotherapy with autologous peripheral blood stem cell transplantation. Development of non-small cell carcinoma was, however, suspected at a site of the residual nodule in cytological examination using bronchoscopy. He then underwent lobectomy, which revealed that the nodule was composed of necrotic tissue. He has been alive without recurrence for seven years. This multimodality treatment appeared to be effective for this patient. However, further investigation is necessary to clarify the role of multimodality treatment.