Diagnosis and treatment of gallbladder and gastric multiple primary malignancies: a rare case report

Multiple primary malignancies are rare and challenging to diagnose when they occur simultaneously. Treatment differs from that of single cancer. A case report describes a patient initially diagnosed with metastatic gallbladder cancer from gastric cancer, but postoperative tests showed concurrent malignancies in both organs. The patient received 3 cycles of SOX neoadjuvant chemotherapy, followed by laparoscopic radical cholecystectomy with liver wedge resection and D2 total gastrectomy with Roux-en-Y reconstruction. Postoperatively, the patient underwent adjuvant SOX chemotherapy, but liver metastasis occurred at 6 months, peritoneal dissemination at 9 months, and she unfortunately died at 11 months after surgery. Interestingly, the patient's gallbladder tumor responded well to SOX chemotherapy, usually used for gastric cancer, despite gallbladder cancer's typical resistance to such treatment. This suggests a need for careful diagnostic methods and personalized treatment approaches. The case also indicates that the SOX regimen might be a new treatment option for gallbladder cancer.