HALP Score in Predicting Response to Treatment in Patients with Early-Stage Gastric Cancer: A Multi-Centred Retrospective Cohort Study

<i>Background and Objectives</i>: The HALP (Haemoglobin, Albumin, Lymphocyte and Platelet) score is used to predict the prognosis of different types of cancer. This study aimed to investigate the role of the HALP score in predicting pathological response in early-stage gastric cancer patients. <i>Materials and Methods</i>: This retrospective cohort study was conducted on 118 patients diagnosed with early-stage gastric cancer and subjected to perioperative (FLOT) treatment between 2018 and 2023. The role of the HALP score in predicting the pathological response to perioperative treatment in patients was investigated. <i>Results</i>: The mean age of the 118 patients included in the study was 61.3 ± 11.1 (min = 23; max = 86). In the ROC analysis, the optimum cut-off value for the HALP score in pathological response classification was found to be 28.9 (AUC = 0.710, sensitivity = 56.7%, specificity = 80%, PPV = 86.79%, NPV = 46.15%). The pathological response rate was 69% in all patients, 87% in patients with a HALP score ≥ 28.9, and 52% in patients with a HALP score < 28.9 (<i>p</i> < 0.001). The probability of pathological response is 6.5 times higher in patients with a HALP score ≥ 28.9. In the Fagan nomogram, when the HALP score was ≥28.9, our pathological response probability estimate (post-test response probability) was found to increase to 64.8% (Positive Likelihood Ratio = 3, Negative Likelihood Ratio = 0.53). In patients with HALP scores ≥ 28.9 and <28.9, progression rates were 16.7% and 47.8%, respectively (<i>p</i> < 0.001), and median survival times were 45.4 and 30.6 months (<i>p</i> < 0.001). <i>Conclusions</i>: The HALP score is a useful and easily accessible score for determining pathological responses in patients with locally advanced gastric cancer.