[Problems concerning the diagnosis and treatment of multiple primary carcinoma of the lung]

Data on 44 patients with multiple primary carcinoma of the lung are presented. Twenty had metachronous tumors, and 24 had synchronous tumors. Twenty-one patients had undergone complete resection for both tumors, and 14 had undergone resection for only one of two tumors. The remaining 9 patients underwent no operation and were treated with photodynamic, radiation and/or chemotherapy. Long-term survival of more than 3 years was achieved for 11 patients, nine of whom had synchronous lesions. Furthermore, they included 3 patients who underwent nonsurgical therapy for both lesions. On the other hand, the prognosis after resection of the second tumor in patients with metachronous lesions was poor. This was thought to be the result of failure to diagnose the second lesion due to incomplete long-term follow-up. We conclude that careful attention to the operative indications is necessary for patients with multiple lesions, particularly lesions such as early squamous cell carcinomas.