Prognostic accuracy of the Hemoglobin,Albumin,Lymphocyte,Platelet (HALP) score in metastatic gastric cancer

After the approval of Institute Ethics Committee, the study will be conducted in the Department of Surgery and Department of Medical Oncology, JIPMER, Puducherry

The details of the patients diagnosed with metastatic gastric cancer (Tumor metastasis in distant organs like liver, lung, parietal peritoneum, nodal metastasis other than regional nodes etc. NCCN, 2024) will be collected from the prospectively maintained retrospective database from January 2013 to December 2022. The patients will be recruited as per the inclusion and exclusion criteria as mentioned above.

Data related to demography, Eastern Cooperative Oncology Group (ECOG) status, smoking or alcohol consumption habits, comorbidities, pathological type of tumor, site and size of the tumour, endoscopic and CECT findings, Tumor, Node, Metastasis (TNM) staging, chemo radiotherapy regimens given, type and indication for surgeries if any, metastases site, basic blood investigations like hemoglobin, albumin, lymphocyte, and platelets will be obtained from the database and no new investigation will be done on patients.

HALP score will be calculated using laboratory values at time of metastasis (or diagnosis of metastatic disease) by multiplying the hemoglobin albumin and lymphocyte/platelet ratio [hemoglobin (g/L) × albumin (g/L) × lymphocyte count/thrombocyte count]20.

Similarly, Neutrophil/lymphocyte ratio and Platelet/lymphocyte ratio will be calculated as follows.

·        The definition of NLR is the absolute value of neutrophil count (ANC) divided by the absolute value of lymphocyte count (ALC) (NLR = ANC/ALC),

·        PLR is the absolute value of platelet count (PLT) divided by ALC (PLR = PLT/ALC)21.

·        Prognostic Nutritional Index (PNI) will be calculated using the following formula. PNI=(10*serum albumin[g/dl])+(0.005*lymphocyte/microL)22

The overall survival will be calculated as the time from the diagnosis to the date of death.

 The optimum cut-off point for HALP score will be calculated from the ROC curve and the patients will be categorized into low and high HALP score groups for further analysis.

All the patients will be followed up during the study period for the outcome variable. The minimum follow-up period will be three years and maximum follow-up period will be 10 years or till the outcome event occurs whichever is earliest.  Data regarding mortality will be obtained from records maintained during follow up visits or through telephonic conversation or during routine follow-up visits.

Simultaneously, optimum cut-off value for other prognostic scores like NLR and PLR will be calculated from the ROC curve and their accuracy in predicting overall survival as opposed to HALP score will be analysed.