Ureteral metastasis of small cell lung cancer transformed from lung adenocarcinoma: A case report

Targeted therapy offers a new option for patients with advanced lung adenocarcinoma patients. However, long‐term targeted therapy may transform lung adenocarcinoma into small cell lung cancer (SCLC). Herein, we report a 48‐year‐old female patient with pulmonary adenocarcinoma and ureteral metastasis which transformed from adenocarcinoma to SCLC after surgical and targeted therapies. She was diagnosed with invasive adenocarcinoma undergoing the surgery. Two years later recurrence and metastasis occurred and she was given targeted therapy with gefitinib and osimertinib. Two years after targeted therapy, a right ureteral mass (4.9 × 3.7 × 3.8 cm) pathologically diagnosed with SCLC was found, which indicated that the pathological subtype has changed from adenocarcinoma to SCLC. Ultimately, multiple metastases occurred after two cycles of chemotherapy consisting of cis‐platinum plus etoposide.