Curative Conversion of Metastatic Gastric Cancer After Pembrolizumab-Trastuzumab-Based Therapy in a PD-L1-Negative, HER2-Positive Patient: A Case Report and Literature Review. MJCR [Internet]. 2026 May 4 [cited 2026 Jun. 13];1(1):30-8. Available from: https://menamedicalresearch.com/journals/index.php/mjcr/article/view/21