Recent Trends in Use of Adjuvant Chemotherapy in Elderly Stage II– III Non-Small Cell Lung Cancer

Takefumi Komiya; Emily Powell; Achuta Kumar Guddati


Transl Lung Cancer Res. 2020;9(4):1180-1186. 

In This Article


SEER is a publicly available cancer research resource that collects data on cancer cases since 1973 from United States state-wide cancer registries.[1] It represents about 28% of the US population, including 18 cancer registries. The SEER database contains information on patient demographics, clinical characteristics, tumor stage, first course treatment, and survival data.[13] This population study used SEER-18 dataset with SEER* stat v. 8.3.5 software.[14–17]

Surgically resected, pathologically confirmed NSCLC cases that were diagnosed between 2004 and 2015 with pathologic stage II–III were identified. AJCC 6th version of TNM staging system, instead of 7th or 8th versions, was used because of availability throughout the period of diagnosis. Information on age, sex, race, histology, presence or absence of chemotherapy in the first course treatment were collected. Cases where chemotherapy use was unknown were assigned into no/unknown category.

Incidence of chemotherapy was assessed according to sex (male vs. female), race (white vs. others), age (20–69 vs. 70–79 vs. 80+), year of diagnosis (2004–2009 vs. 2010–2015), histology (adenocarcinoma vs. others), and pathologic stage (II vs. III). SEER dataset does not define the timing of chemotherapy in relation to surgery, e.g., neoadjuvant, adjuvant, although it counts only for first course treatment. Information about systemic treatment for recurrent/metastatic setting was not available. Elderly patients with age 70+ were then divided into two groups (70–79 vs. 80+) for subset analyses.

Univariate and multivariate analyses were conducted using JMP version 13 (SAS Institute, Cary, NC, USA). A two-tailed P value less than 0.05 was considered as statistically significant.

This is a population study that involves no identifiable information for individuals throughout the analyses. This study was reviewed by the institutional review board and was considered exempt from human subject research.