Children undergoing ABMT, a procedure which entails massive doses of chemotherapy along with total-body irradiation, are candidate to develop severe gastrointestinal toxicity and prolonged anorexia requiring administration of Parenteral Nutrition (PN) for variable periods. We report a series of 35 consecutive children affected by malignancies who underwent 37 courses of PN after ablative therapy followed by ABMT. Age ranged from 8 months to 17 years; 16 were females, 19 males. There were 23 cases of neuroblastoma, 5 of Wilms' tumor, 3 of acute myelogenous leukemia, 2 of Ewing's sarcoma, 1 case each of rhabdomyosarcoma and acute lymphoblastic leukemia. All patients developed severe neutropenia for 9-42 days (median 18 d). Fever occurred in all patients; sepsis was documented in 10. Duration of PN ranged from 10 to 64 days (23 +/- 9; mean +/- SD). PN solution, containing crystalline L-Aminoacids (8.5%) mixed with 33% glucose, minerals, trace elements and vitamins provided for children a caloric intake of 49.8 +/- 17.3 Kcal/Kg/day with a nitrogen intake of 0.26 +/- 0.27 g/Kg/day. Nutritional assessment, utilizing percent ideal body weight, serum protein electrophoresis, C3, pseudocholinesterase and fibrinogen, was performed at the beginning and at the completion of each course of PN. Mean percent ideal body weight was 95.8 before PN, 98.5 on last day of PN (p less than 0.0005). Other parameters did not change significantly. No metabolic complication nor severe electrolyte imbalance were observed except for 5 patients who developed hypokalemia in coincidence with administration of Amphotericin B.(ABSTRACT TRUNCATED AT 250 WORDS)