title: Efficacy of first-line erlotinib in non-small cell lung cancer patients undergoing dose reduction and those with a low body surface area: A population-based observational study by the Ibaraki Thoracic Integrative (POSITIVE) Research Group.
abstract: The aim of the present study was to evaluate the efficacy of erlotinib, one of the epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs), in patients undergoing dose reduction and in those with a low body surface area (BSA). The association between dose reduction, low BSA and efficacy, including response rate, disease control rate, time to treatment failure and overall survival, were evaluated in patients prescribed first-line erlotinib for EGFR mutated non-small cell lung cancer patients between April 2012 and March 2015. A total of 22 patients received first-line erlotinib during the study period. A dose reduction of erlotinib for the reason of low BSA and poor performance status occurred in 14 (63.6%) of the patients: 6 (27.3%) had initial dose reduction, 6 (27.3%) had dose reduction in their clinical courses, and 2 (9.1%) had both. Dose reduction of erlotinib with the initial dose of erlotinib/BSA was >80 mg/m2, and longest-term prescribed dose of erlotinib/BSA was >50 mg/m2, which may have no association with a survival disadvantage. Dose-reduction estimation studies for TKIs may be crucial, particularly for patients with a low BSA. Future prospective studies and confirmation of these results in population-based retrospective ones investigating the incidence of dose reduction in patients with AEs and those with low BSA may be required for the efficient use of erlotinib in common clinical practice.
authors.affiliation: Divisions of Thoracic Surgery and Respiratory Medicine, Tsuchiura Kyodo General Hospital and Regional Cancer Center, Tsuchiura, Ibaraki 300-0053, Japan.
authors.forename: Masaharu
authors.initials: M
authors.lastname: Inagaki
authors.affiliation: Divisions of Thoracic Surgery and Respiratory Medicine, Tsuchiura Kyodo General Hospital and Regional Cancer Center, Tsuchiura, Ibaraki 300-0053, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Shinohara
authors.affiliation: Division of Respiratory Medicine, Ibaraki Prefectural Central Hospital and Regional Cancer Center, Kasama, Ibaraki 309-1793, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kaburagi
authors.affiliation: Division of Respiratory Medicine, Faculty of Clinical Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8576, Japan.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Homma
authors.affiliation: Division of Respiratory Medicine, Faculty of Clinical Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8576, Japan.
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Hizawa
authors.affiliation: Divisions of Thoracic Surgery and Respiratory Medicine, Tokyo Medical University, Ibaraki Medical Center Hospital, Ami, Ibaraki 300-0395, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nakamura
authors.affiliation: Division of Respiratory Medicine, Ibaraki Higashi National Hospital, Tokai, Ibaraki 319-1113, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Hayashihara
authors.affiliation: Division of Respiratory Medicine, Ibaraki Higashi National Hospital, Tokai, Ibaraki 319-1113, Japan.
authors.forename: Takefumi
authors.initials: T
authors.lastname: Saito
authors.affiliation: Division of Respiratory Medicine, Tsukuba Medical Center Hospital and Regional Cancer Center, Tsukuba, Ibaraki 305-8558, Japan.
authors.forename: Hiroichi
authors.initials: H
authors.lastname: Ishikawa
authors.affiliation: Divisions of Thoracic Surgery and Respiratory Medicine, Hitachi General Hospital, Hitachi, Ibaraki 317-0077, Japan.
authors.forename: Hideo
authors.initials: H
authors.lastname: Ichimura
authors.affiliation: Divisions of Thoracic Surgery and Respiratory Medicine, Hitachi General Hospital, Hitachi, Ibaraki 317-0077, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nawa
authors.affiliation: Division of Respiratory Medicine, Kasumigaura Medical Center, Tsuchiura, Ibaraki 300-0812, Japan.
authors.forename: Norihiro
authors.initials: N
authors.lastname: Kikuchi
authors.affiliation: Division of Respiratory Medicine, Ryugasaki Saiseikai General Hospital, Ryugasaki, Ibaraki 301-0854, Japan.
authors.forename: Kunihiko
authors.initials: K
authors.lastname: Miyazaki
authors.affiliation: Division of Respiratory Medicine, Ryugasaki Saiseikai General Hospital, Ryugasaki, Ibaraki 301-0854, Japan.
authors.forename: Takahide
authors.initials: T
authors.lastname: Kodama
authors.affiliation: Division of Thoracic Surgery, Tsukuba Kinen General Hospital, Tsukuba, Ibaraki 300-2622, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Kamiyama
authors.affiliation: Division of Respiratory Medicine, Mito Medical Center, Institute of Clinical Medicine, University of Tsukuba, Mito, Ibaraki 310-0015, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Satoh
authors.affiliation: Divisions of Thoracic Surgery and Respiratory Medicine, Tokyo Medical University, Ibaraki Medical Center Hospital, Ami, Ibaraki 300-0395, Japan.
authors.forename: Kinya
authors.initials: K
authors.lastname: Furukawa
keywords: dose reduction; erlotinib; first-line; population-based; retrospective; survival