Systemic Treatment Patterns With Advanced or Recurrent Non-small Cell Lung Cancer in Japan: A Retrospective Hospital Administrative Database Study

Abstract

Purpose: Data on the treatment of non-small cell lung cancer (NSCLC) in real-world clinical practice in Japan are limited. This large-scale, retrospective cohort study examined data on patients' characteristics and systemic therapies for advanced or recurrent NSCLC in routine practice in Japan.

Methods: This study used an electronic health records-based database of health claims and Diagnosis Procedure Combination data from 215 consenting hospitals in Japan. Records from April 2008 to September 2015 were analyzed. Regimens were examined by histology, age, sex, and therapeutic line. Logistic regression analysis was performed to predict which clinical and demographic factors affected patients' probability of receiving first- or second-line therapy or completing first-line platinum-based chemotherapy.

Findings: Among 16,413 patients, 67.9%, 39.2%, and 22.3% received first-, second-, and third-line systemic treatment, respectively. Treatment was more common in patients aged <75 versus ≥75 years (76.0% vs 51.6%), in female versus male patients (71.6% vs 65.4%), and in patients with nonsquamous versus squamous disease (75.6% vs 61.9%). More than 30 systemic regimens were administered. The most common first-line therapy was platinum-based chemotherapy (nonsquamous, 53.6%; squamous, 73.7%). Non-platinum-based chemotherapy use increased in the second-line setting, but platinum-based chemotherapy use remained high (nonsquamous, 33.9%; squamous, 38.6%). Tyrosine kinase inhibitors were used in 32.0% and 29.4% of patients with nonsquamous NSCLC in the first- and second-line settings, respectively. Switches from first- to second-line platinum-based chemotherapy and from first- to second-line tyrosine kinase inhibitors occurred. Forty-two percent of the patients died during hospitalization. In the logistic regression analysis, factors associated with a decreased likelihood of receiving first-line therapy were male sex, squamous histology, age >75 years, treatment at a general (vs cancer-specific) hospital, worse scores on certain activities of daily living, presence of chronic pulmonary disease, worse Hugh-Jones classification, and positive smoking status. The likelihood of completing first-line platinum-based chemotherapy was increased with greater body mass index, better activities of daily living scores, absence of chronic pulmonary disease, and better Hugh-Jones classification. The likelihood of continuing with second-line therapy was decreased with older age and recurrence of NSCLC.

Implications: Systemic treatment patterns for advanced or recurrent NSCLC in Japan were varied. Nearly 30% of all patients and approximately half of elderly patients did not receive systemic treatment. Treatment rates declined with subsequent therapeutic lines. Generally, guidelines were followed with first-line treatment administration, but not with second-line administration. These results underscore the need for better guideline adherence and more optimal treatment in and elderly patients and in those receiving later-line treatment in Japan.

Keywords: Japan; non–small cell lung cancer; real-world data; retrospective study.