Metabolism in hematologic malignancy

The authors used isotopic infusions of 6‐3H‐glucose, U‐14C‐glucose, and 14C‐urea and calorimetry to investigate energy expenditure and metabolic profiles in 19 patients with hematologic malignancy. The average age of these patients was 62 years. Eleven patients had either leukemia or myeloproliferative disorders (LEMP). The rest had lymphoma (LYMPH). The Resting Energy Expenditure (REE) in the LYMPH patients was 1015 ± 115 kcal/24 hr. This value in the LEMP group was significantly elevated at 2083 ± 270 kcal/24 hr (P < 0.025) despite similar weights and ages between the two groups. Net Protein Catabolism (NPC) in the LYMPH group was 82 ± 29 mg/kg. hr. In contrast the value in the LEMP group was more than doubled at 174 ± 30 mg/kg. hr (P < 0.05). Glucose production in the LYMPH group was 14.1 ± 2.7 μmol/kg. min, and the percent of glucose uptake oxidized in the LYMPH group was 37% ± 9%. In contrast, glucose production in the LEMP group was significantly elevated (P < 0.025) at 41.0 ± 8.1 μmol/kg. min, and the percent of glucose uptake oxidized was significantly depressed (P < 0.05) at 20% ± 4% compared with the value in the LYMPH group. Glucose recycling in the LYMPH group was 9.0% ± 6%. In the LEMP group the rate of recycling was significantly elevated at 60.3% ± 4.8% (P < 0.005). The percent suppression of endogenous glucose turnover during glucose infusion in the LYMPH group was 96% ± 4%. The value for the LEMP patients was significantly less at 30.2% ± 5% (P < 0.0005). The serum cortisol concentration in the LYMPH patients was 285 ± 74 nmol/l. The value in the LEMP patients was significantly higher (P < 0.005) at 579 ± 22 nmol/l. The authors concluded that hematologic malignancy is not a homogeneous group when evaluated metabolically. Lymphoma patients are similar metabolically to normal volunteers, but LEMP patients form a distinct group with major abnormalities in both glucose and protein kinetics and energy expenditure.