FACTORS PREDICTING RESPONSE TO NEOADJUVANT CHEMOTHERAPY IN LOCALLY ADVANCED GASTRIC CANCER/LOKAL ILERI MIDE KANSERINDE NEOADJUVAN KEMOTERAPIYE YANITI ONGOREN FAKTORLER

Objective: In the treatment of local advanced gastric cancer (LAGC), it is recommended to start with neoadjuvant chemotherapy (NAC). Although the benefits of NAC have been shown, it is still not fully understood which patients respond better. The aim of this study was to investigate the effect of hematological and histopathological parameters on the response to chemotherapy. Materials and Methods: A retrospective examination was made of 38 patients who underwent surgery for LAGC after receiving NAC. Evaluations were made by comparing the demographic characteristics, histopathological characteristics in an endoscopic biopsy of the tumor, preoperative hemoglobin levels, and neutrophil-lymphocyte ratios with the postoperative pathological response to determine which tumor characteristics gave a better response. Results: In the postoperative histopathological evaluation, there was a pathological complete response to chemotherapy in two patients (6%), grade 1 in 9 patients (24%), grade 2 in 13 patients (34%), and grade 3 in 14 patients (36%). A statistically significant relationship was determined between the histopathological absence of perineural invasion and pathological complete response (p=0.023). Conclusion: A relationship between perineural invasion and poor response to chemotherapy was determined. Although not at a statistically significant level, there was also observed to be a poor response to chemotherapy in the presence of low grade and lymphovascular invasion. Keywords: Local advanced gastric cancer, neoadjuvant chemotherapy response, pathological complete response, perineural invasion Amac: Lokal ileri mide kanserinde (LIMK) tedaviye neoadjuvan kemoterapi (NAK) ile baslanmasi onerilir. Ancak NAK'nin faydalari gosterilmis olsa da hangi hasta gurubunun tedaviye daha iyi yanit verdigi tam olarak anlasilamamistir. Calismamizda hematolojik ve histopatolojik parametrelerin kemoterapi yaniti uzerine etkisi arastirilmistir. Yontem ve Gerec: Bu calismada lokal ileri evre mide kanseri nedeni ile neoadjuvan kemoterapi gorup sonrasinda ameliyat edilen 38 hasta retrospektif olarak incelendi. Ameliyat sonrasi patolojik yanit ile hastanin demografik ozellikleri, tumorun endoskopik biyopsideki histopatolojik ozellikleri, preoperatif hemoglobin seviyesi, notrofil lenfosit orani karsilastirilip hangi ozellikteki tumorlerin daha iyi yanit verdigi degerlendirildi. Bulgular: Ameliyat sonrasi yapilan histopatolojik degerlendirmede 2 (%6) hastada patolojik tam yanit, 9