Medical Care Costs for Recurrent versus De Novo Stage IV Cancer by Age at Diagnosis

Objective Data Sources/Study Setting To address the knowledge gap regarding medical care costs for advanced cancer patients, we compared costs for recurrent versus de novo stage IV breast, colorectal, and lung cancer patients. Virtual Data Warehouse (VDW) information from three Kaiser Permanente regions: Colorado, Northwest, and Washington. Study Design Principal Findings We identified patients aged >= 21 with de novo or recurrent breast (n(de novo) = 352; n(recurrent) = 765), colorectal (n(de novo) = 1,072; n(recurrent) = 542), and lung (n(de novo) = 4,041; n(recurrent) = 340) cancers diagnosed 2000-2012. We estimated average total monthly and annual costs in the 12 months preceding, month of, and 12 months following the index de novo/recurrence date, stratified by age at diagnosis (<65, >= 65). Generalized linear repeated-measures models controlled for demographics and comorbidity. In the pre-index period, monthly costs were higher for recurrent than for de novo breast (<65: +$2,431; >= 65: +$1,360), colorectal (<65: +$3,219; >= 65: +$2,247), and lung cancer (<65: +$3,086; >= 65: +$2,260) patients. Conversely, during the index and post-index periods, costs were higher for de novo patients. Average total annual pre-index costs were five- to ninefold higher for recurrent versus de novo patients Conclusions Cost differences by type of advanced cancer and by age suggest heterogeneous patterns of care that merit further investigation.