Clinical characteristics and outcomes of surgically resected small cell lung cancer diagnosed postoperatively: a retrospective analysis

Small cell lung cancer (SCLC) is characterized by rapid progression and a poor prognosis, with chemoradiotherapy being the standard treatment. Surgical resection is traditionally limited strictly to early-stage disease. However, there are cases in which patients undergo resection with a preoperative diagnosis of non-small cell lung cancer, only to be confirmed as having SCLC postoperatively. We retrospectively investigated eight patients who underwent pulmonary resection at our institution between 2017 and 2024 and were diagnosed with SCLC on postoperative pathology. Clinical characteristics, perioperative outcomes, adjuvant therapy, recurrence patterns, and survival were assessed. The cohort included four men and four women with a median age of 71.7 years (range, 55–84). The median Brinkman Index was 740. Clinical stage ranged from IA to IIB. All patients underwent lobectomy with systematic lymph node dissection. Adjuvant therapy was administered in four patients. Recurrence occurred in two patients with p-stage IIIA disease. During a median follow-up of 72 months, five patients remained alive without recurrence, including one with p-stage IIIA disease who survived for 93 months. pN0 status and receipt of adjuvant therapy were associated with a favorable prognosis. Long-term survival was observed in some patients with surgically resected SCLC diagnosed postoperatively. These findings highlight the importance of optimizing multidisciplinary treatment strategies including surgery.