Abstract
Background. Reports of pulmonary adenosquamous cell carcinoma which form following chemoradiation therapy for small cell lung carcinoma are rare. Case. A 65-year-old man, who had received chemoradiation therapy for a limited stage small cell lung carcinoma (SCLC) located in the left upper lobe, and who achieved complete response (CR) in 1995, had been followed up in our hospital and had shown no sign of recurrence until 2007. However, he complained of hoarseness, and therefore we performed chest CT scanning, but this showed only unchanged SCLC post-treatment scar in the left upper lobe. We suspected laryngeal cancer, and he was examined by fluorodeoxyglucose-positron emission tomography (FDG-PET) which showed an increased uptake of FDG in the larynx and in the scar region in the left upper lobe. A transbronchial lung biopsy specimen from the scar region showed squamous cell carcinoma. We administered chemoradiation therapy for laryngeal cancer, but a second FDG-PET scan showed a remaining area of high FDG uptake in the scar region. In January 2008, left upper lobectomy was performed. The final pathological diagnosis was adenosquamous cell carcinoma, which was different from the typical appearance of SCLC recurrence or metastasis of laryngeal cancer. Conclusion. We encounterd a case of pulmonary adenosquamous cell carcinoma which may have formed from the cicatricial tissue following chemoradiation therapy for SCLC.
