Increasing utilization and predictors of hematopoietic growth factors in patients diagnosed with colorectal cancer: findings from a large national population-based cohort in the USA, 1992-2009.

None of previous studies has provided the detailed pattern, variation, and temporal trend in the use of growth factors for patients with colorectal cancer. The aim of the study was to examine the temporal trend and predictors of receiving hematopoietic growth factors in a large nationwide and population-based cohort of patients with colorectal cancer in the USA from 1992 to 2009. We studied 50,768 patients diagnosed with colorectal cancer at age 65-89 years in 1992-2009 in the Surveillance, Epidemiology and End Results areas who received chemotherapy as part of initial therapy within 12 months of diagnosis according to Medicare data. Growth factors were identified for colony-stimulating factors (CSFs) and for erythropoiesis-stimulating agents (ESAs). Overall, 16.3% received CSFs and 26.5% received ESAs with an increase from 0.8 and 1.5% in 1992 to 29.4 and 14.1% in 2009, respectively. Compared with patients diagnosed in 1992-1994, those diagnosed in 1995-1997 were >2 times more likely to receive CSFs and ESAs, whereas patients diagnosed recently in 2007-2009 were >22 times and 4 times to receive CSFs and ESAs, respectively. Gender, marital status, comorbidity scores, geographic area, year of diagnosis, tumor stage, number of lymph nodes, and risk profile for febrile neutropenia were statistically significant predictors of using CSFs and ESAs. There were substantial temporal and geographic variations in the use of hematopoietic growth factors in patients with colorectal cancer following chemotherapy. More studies would be needed to explore the effectiveness of hematopoietic growth factors in preventing and treating neutropenia, anemia, and infection.