Factors affecting receipt of expensive cancer treatments and mortality: evidence from stem cell transplantation for leukemia and lymphoma

Abstract

Objective: To identify factors that affect whether patients diagnosed with either leukemia or lymphoma receive a stem cell transplant and secondly if receipt of stem cell transplantation is linked to improved survival.

Data: California inpatient discharge records (2002-2003) for patients with either leukemia or lymphoma linked with vital statistics death records (2002-2005).

Study design: Bivariate Probit treatment effects model that accounts for both the type of treatment received and survival while controlling for nonrandom selection due to unobservable factors.

Principal findings: Having private insurance coverage and residence in a well-educated county increased the chances a patient with either disease received HSCT. Increasing age and travel distance to the nearest transplant hospital had the opposite effect. Receipt of HSCT had a significant impact on mortality. We found the probability of death was 4.3 percentage points higher for leukemia patients who did NOT have HSCT. Receipt of HSCT reduced the chances of dying by almost 50 percent. The likelihood of death among lymphoma patients who underwent HSCT was almost 5 percentage points lower, a 70 percent reduction in the probability of death.

Conclusions: The findings raise concern about access to expensive, but highly effective cancer treatments for patients with certain hematologic malignancies.

Keywords: Leukemia; access; bivariate probit; insurance; lymphoma; stem cell transplantation; survival.