Successful conversion therapy of advanced gallbladder carcinoma by chemotherapy combined with immunotherapy: two case reports.

Gallbladder cancer (GBC) is a highly aggressive malignancy of the biliary system and is frequently diagnosed at an advanced stage upon initial presentation. Nonetheless, the introduction of conversion therapy has allowed certain initially inoperable cases of GBC to become candidates for radical resection after comprehensive modalities, including chemotherapy, immunotherapy, and radiotherapy. In the current retrospective analysis, we present two patients with initially unresectable GBC treated at Xiangyang Central Hospital, affiliated with Hubei University of Arts and Science. After receiving a combination of chemotherapy and immunotherapy, substantial tumor regression was observed at both primary and metastatic sites, achieving partial remission according to the Response Evaluation Criteria in Solid Tumors (RECIST). Conversion therapy proved effective, enabling both patients to undergo successful radical resections. Following surgery, the original therapeutic regimen was continued until completion of five cycles. Follow-up extended through November 2025, with no evidence of tumor recurrence observed.