[A Case of Sigmoid Colon Cancer with Synchronous Pulmonary Metastases Diagnosed during Follow-Up after Primary Tumor Resection].

A 62-year-old woman was admitted and underwent endoscopic mucosal resection for sigmoid colon cancer.Histopathological examination revealed submucosal invasion of 3,000 μm with positive tumor budding(Grade 2).Subsequently, she underwent laparoscopic sigmoidectomy with D2 lymphadenectomy.Postoperative pathology showed no regional lymph node metastasis, and the disease was staged as pStage Ⅰ.Chest CT scans revealed small nodules in the right middle lobe and left lower lobe that had been noted preoperatively and demonstrated gradual enlargement.Twenty four months after the initial surgery, these were diagnosed as synchronous pulmonary metastases, and she underwent thoracoscopic partial resections of both lungs.Nonetheless, the patient remains alive, with no recurrence 10 years after the resection of the pulmonary metastases.