Akademik Veri Yönetim Sistemi
Journal of Cancer Research and Therapeutics, cilt.20, sa.3, ss.1045-1048, 2024 (SCI-Expanded)
Gastric cancer (GC) is an aggressive malignancy; 5.0% of GC patients are diagnosed before the age of 40. These patients are more aggressive and advanced stage at the diagnosis. Microsatellite instability‑high (MSI‑H) status is usually seen in relatively older patients. We report a 31‑year‑old male patient presenting with an intra‑abdominal mass and spleen lesions that radiologically mimic a gastrointestinal stromal tumor (GIST). He underwent surgery. Histological examination revealed poorly differentiated adenocarcinoma starting from the deep gastric mucosa. After surgery, rapidly progressive disease was observed. The patient with MSI‑H and combined positive score (CPS) of 65% was treated with a combination of immunotherapy and chemotherapy; complete response was observed in approximately 3 months. This is a very rare GC case in young adult age with MSI‑H status and responds to treatment in a short time. Predictive markers for immunotherapy efficacy are still being discussed; this case supports the predictive role of high CPS score and MSI‑H phenotype in demonstrating treatment efficacy.