Spontaneous Regression of Small Cell Lung Cancer: A Case Report

Spontaneous regression (SR) is extremely rare in small cell lung cancer (SCLC). The present study reports a rare case of SCLC accompanied by partial SR in a 68-year-old man. The patient was scheduled to receive chemoradiotherapy for SCLC. Computed tomography (CT) simulation images for radiotherapy revealed partial regression of the primary tumor, while lymph node metastasis progression was observed. On 18F-fluorodeoxyglucose (FDG) positron emission tomography/CT, an abnormally high uptake of FDG was not observed in the primary exhibiting SR, while an extremely high uptake was identified in the lymph node metastases. The patient also presented with bilateral double vision, which suggested neurological paraneoplastic syndrome. He received chemoradiotherapy and a complete response was obtained. Until the last follow-up (58 months since the initiation of chemoradiotherapy), the patient was free from tumor progression.