Exceptional 106-month survival in multiply relapsed small cell lung cancer after sequential anlotinib and short-course sintilimab: a case report.

Background: Small cell lung cancer (SCLC) is highly aggressive, and durable disease control after multiple treatment lines is uncommon. Anti-angiogenic therapy combined with PD-1 blockade may provide complementary antitumor effects through vascular and immune microenvironment remodeling. Case presentation: We report a 64-year-old never-smoking woman diagnosed with limited-stage SCLC in September 2017. She achieved a partial response after concurrent chemoradiotherapy but developed recurrence in November 2018 and subsequently progressed after irinotecan-based and pemetrexed-based chemotherapy. Anlotinib was initiated in August 2019 and achieved radiologic tumor regression. In May 2020, biopsy of a right submandibular lymph node confirmed extrathoracic metastatic SCLC. Sintilimab was added to ongoing anlotinib in June 2020, and a partial response was achieved after three cycles. Grade 2 immune-related hypothyroidism developed during combination therapy, and sintilimab was discontinued. Anlotinib monotherapy was subsequently continued as maintenance treatment. At the latest follow-up in July 2026, the patient remained alive with stable disease, with an overall survival of 106 months from initial diagnosis. Conclusions: This case highlights exceptionally durable disease control in multiply relapsed SCLC following sequential anlotinib and short-course sintilimab. The sustained activity of anlotinib, reactivation of antitumor immunity by PD-1 blockade, and potential vascular-immune interaction may have jointly contributed to the prolonged outcome. However, because anlotinib had demonstrated activity before immunotherapy and was continued after sintilimab discontinuation, the relative contribution of each treatment cannot be determined. Further prospective studies with biomarker analyses are warranted.