Objective This study assessed the weight loss changes and gastrointestinal symptoms in patients with advanced tumors receiving platinum-containing chemotherapy.Methods We retrospectively reviewed 297 patients with advanced cancers[124 gastrointestinal (GI) cancer patients,119 lung cancer patients and 54 head and neck cancer (HNC) patients]receiving first-line chemotherapy at Tongji Hospital.The patients' changes in body weight,body mass index (BMI),and biochemical parameters (serum haemoglobin and albumin levels) were compared before and after two chemotherapy cycles.Results More than half[54.88％ (163/297)]of the patients had experienced unintentional weight loss in the 6 months before chemotherapy,and weight loss ＞ 5％ and ＞ 10％ of the body mass was noted in 35.69％ and 20.20％ of the patients,respectively.After two cycles of platinum-based chemotherapy,the proportions of patients with a ＞ 5％ reduction in body weight among patients with GI,lung,and head and neck cancers were 47.5％ (59/124),44.53％ (53/119),and 46.2％ (25/54),respectively.The patients with GI and lung cancers were more vulnerable to extreme weight loss (＞ 10％) than those with HNC (P =0.025).The serum hemoglobin levels were also remarkably decreased relative to those before chemotherapy (all P ＜ 0.05).Common GI symptoms reported by all patients included anorexia (61.28％),vomiting (52.53％),and nausea (51.18％).A higher proportion of patients with ＞ 10％ weight loss experienced anorexia and vomiting (OR =12.21 and 3.61,P =0.008 and 0.047,respectively).Conclusions For advanced cancer patients receiving platinum-based chemotherapy,the GI symptoms are the major factor related to their nutritional status.Appropriate nutritional screening,evaluation and treatment should be applied during the treatment of cancer in order to reduce GI symptoms and improve the patient's nutritional status.