Frailty Scales for Predicting Chemotherapy Toxicity in Older Adults With Gastrointestinal Cancers

"Patients aged 65 years and older with non-metastatic or locally advanced gastrointestinal cancers will receive standard adjuvant chemotherapy regimens as part of routine clinical practice. Regimens may include FOLFOX, CAPEOX, FOLFIRI, FOLFOXIRI, FOLFIRINOX, capecitabine, gemcitabine, 5-FU/leucovorin, or oxaliplatin-based combinations, depending on tumor type and physician decision.~No investigational drugs or experimental interventions are administered. The study is observational, and all treatments follow standard of care."