<![CDATA[Background: Older adults with advanced solid tumors are at heightened risk of chemotherapy-induced myelotoxicity, which can compromise treatment delivery and outcomes. Risk stratification tools such as the Cancer and Aging Research Group Chemotherapy Toxicity Tool (CARG-TT) and the Chemotherapy Risk Assessment Scale for High-Age Patients (CRASH) exist, but their performance in Indonesia remains uncertain. A locally validated, accurate predictor is needed to guide treatment intensity, monitoring, and allocation of limited resources. This study evaluates and compares the predictive performance of CARG-TT and CRASH for severe myelotoxicity in Indonesian older adults with advanced solid tumors. Methods: This study applied a retrospective cohort design involving 109 geriatric patients aged 60 years or older with stage III or IV solid tumors who received chemotherapy at Mohammad Hoesin General Hospital, Indonesia, between September 2022 and 2024. Pre-chemotherapy assessments were performed using CARG-TT and CRASH. Severe myelotoxicity was defined in accordance with the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0, including grade 3 or higher anemia (hemoglobin <8 g/dL), leukopenia (leukocyte count <2000/mm³), neutropenia (absolute neutrophil count <1000/mm³) with or without febrile neutropenia, and/or thrombocytopenia (platelet count <50,000/mm³). Receiver operating characteristic (ROC) curve analysis was conducted to compare the predictive performance of both scoring systems. Statistical analyses were conducted using SPSS version 26.0, with a p-value of < 0.05 considered statistically significant. Results: Among the 109 patients analyzed (mean age: 67.2 years; 54.1% female), 81 (74.3%) experienced severe myelotoxicity during chemotherapy. The median CARG-TT and CRASH scores were 10 and 8, respectively. The ROC-AUC for CRASH was 0.726 (95% CI: 0.633–0.807), significantly outperforming CARG-TT, which had an AUC of 0.610 (95% CI: 0.511–0.702; p = 0.022). CRASH demonstrated superior sensitivity and specificity in identifying high-risk patients. Conclusions: The CRASH score outperformed the CARG-TT in predicting severe myelotoxicity among older adults with advanced solid tumors receiving chemotherapy. ]]>
