Biopsy Procedures and Molecular Testing Utilization and Related Costs in Patients with Metastatic Lung Cancer

Epidermal growth factor receptor (EGFR) gene mutations and anaplastic lymphoma kinase (ALK) gene rearrangements are key therapeutic targets for biomarker-driven treatment with an EGFR or ALK tyrosine kinase inhibitor (TKI) in patients with metastatic non-small cell lung cancer (NSCLC). To appropriately guide treatment decisions, since 2011, the National Comprehensive Cancer Network and the American Society of Clinical Oncology therefore recommend EGFR and ALK analysis in tumor samples obtained at the time of diagnosis in patients with non-squamous NSCLC. Currently, there are limited data on utilization patterns and cost of biopsy procedures and biomarker tests in patients with metastatic NSCLC who receive an EGFR or ALK TKI.

To (a) describe utilization patterns and costs associated with biopsy procedures and biomarker testing in patients with NSCLC who received erlotinib or crizotinib between 2009 and 2012 and (b) investigate the timing of these procedures relative to the erlotinib or crizotinib index date.

Adult patients with metastatic lung cancer were identified by ICD-9-CM diagnostic codes within the Truven Health Analytic MarketScan database. Patients were included in the analysis if they had an index erlotinib or crizotinib claim between January 1, 2009, and September 30, 2012 (index period) and were continuously enrolled for ≥ 12 months before the index claim. Because there is no specific ICD-9-CM diagnostic code for NSCLC, patients with metastatic lung cancer who received erlotinib or crizotinib were considered to have metastatic NSCLC. Using CPT and ICD-9-CM codes, lung biopsy procedures performed during the 24 months before or 12 months after the index claim date were identified. For every patient, biomarker testing claims for EGFR and ALK were identified using the molecular pathology stacked CPT code during the 2 months before or 1 month after the index date. The frequency of claims for biopsy procedures and biomarker testing was analyzed descriptively. The overall summary measures for biomarker testing, especially frequency of EGFR testing in patients receiving erlotinib, was also described as before and after 2011, the year when biomarker testing became part of the guidelines. Per patient and overall costs for biopsy procedures and biomarker testing were calculated from payer and patient perspectives.

Of the 4,926 identified patients, 4,801 (97.5%) received erlotinib, and 125 (2.5%) received crizotinib. Biopsy procedure claims were identified for 3,579 (72.7%) patients, including 3,503 (73.0%) erlotinib recipients and 76 (60.8%) crizotinib recipients. Biomarker testing claims were identified for 675 (13.7%) patients, including 634 (13.2%) erlotinib recipients and 41 (32.8%) crizotinib recipients. Overall, most biomarker testing procedures (476 of 741) were identified in 435 (of 675) patients after year 2011. Also, among erlotinib recipients, percentage of patients receiving EGFR testing was increased over the index period. Per patient mean (SD) numbers of biopsy procedures and biomarker tests were 1.2 (1.1) and 0.2 (0.4), respectively. In the outpatient setting, per patient mean (SD) cost per biopsy procedure was $1,223 ($1,899) from the payer perspective and $60 ($147) from the patient perspective, whereas in the inpatient setting, it was $8,163 ($18,712) and $180 ($691), respectively. Among patients receiving at least 1 biomarker test, the per patient mean (SD) cost for the overall population was $891 ($1,062) and $43 ($229); for erlotinib recipients, it was $906 ($1,084) and $42 ($228); and for crizotinib recipients, it was $664 ($576) and $55 ($243) in payer and patient perspectives, respectively.

This study provides insight into the use and cost of biopsy and biomarker testing procedures in patients with metastatic NSCLC. The low frequency of biomarker testing highlights the need for more awareness of testing to guide treatment decisions in these patients. Costs associated with biopsy procedures and biomarker testing provide insight into the economic impact on metastatic NSCLC patients treated with targeted therapy.

This study was sponsored by Merck & Co. Shinde is a study manager working for Merck under contract with AllSourcePPS, an Agile 1 company in Huntington Beach, California. Cao and Kothari are employees of Merck & Co., Kenilworth, New Jersey. Study concept and design were contributed primarily by Shinde and Kothari. Data analysis was performed by Cao. Data interpretation was performed by Shinde, Cao, and Kothari. Shinde wrote the manuscript with assistance from Cao and Kothari. The revision was completed primarily by Shinde and Kothari.