OBJECTIVES: Treatments for metastatic non–small cell lung cancer (mNSCLC) vary depending on histologic subtype and may have differential impact on economic outcomes. We therefore examined disease-related healthcare and cancer-directed treatment costs by histologic subtype among patients with mNSCLC.
METHODS: We identified patients aged greater than or equal to 65 years diagnosed with mNSCLC between 2000 and 2011 using the SEER–Medicare linked database. Patients with initial diagnosis at earlier-stage disease were required to have greater than or equal to 1 subsequent diagnosis of secondary metastases (ICD-9-CM codes: 196.xx-198.xx). The first mNSCLC diagnosis date defined the index date; patients were followed from index until death or database end (12/31/2012). Patients were stratified by squamous versus nonsquamous histology. Disease-related costs consisted of Medicare-reimbursed costs on healthcare claims for inpatient admissions, ambulatory care visits, and hospice care with a cancer-related diagnosis code, as well as cancer-directed treatment claims defined by biologic therapy, chemotherapy, radiation, and surgery. We used multivariable generalized linear models adjusting for demographic and clinical characteristics to examine cost differences by histologic subtype.
RESULTS: Overall, 138,214 patients met the inclusion criteria, of whom 23.3% had squamous mNSCLC and 76.7% had nonsquamous mNSCLC. The proportion of patients receiving cancer-directed treatment was higher among those with squamous versus nonsquamous mNSCLC (72.2% vs. 60.6%; chi-square p less than 0.0001). Adjusted mean per-patient per-month cancer- directed treatment costs were slightly lower among patients with squamous versus nonsquamous mNSCLC ($3,332 vs. $3,440; p less than 0.0001). Additionally, adjusted mean per-patient per-month total disease-related healthcare costs were significantly lower for patients with squamous versus nonsquamous mNSCLC ($13,862 vs. $14,690; p less than 0.0001).
CONCLUSIONS: Patients with nonsquamous mNSCLC had higher cancer-directed treatment costs and total disease-related costs compared to those with squamous mNSCLC. Given the paucity of evidence comparing costs of squamous versus nonsquamous mNSCLC, this research should be reproduced in similar settings using other real-world data sources to evaluate the generalizability of these findings.
