Open AccessTime-Varying Pattern of Postoperative Recurrence Risk of Early-Stage (T1a-T2bN0M0) Non-Small Cell Lung Cancer (NSCLC): Results of a Single-Center Study of 994 Chinese Patients
Author(s) -
Zhu Jing-ci,
Xing Feng,
Xuewen Zhang,
Ying Sheng Wen,
Peng Lin,
Tie Hua Rong,
Ling Cai,
Lan Jun Zhang
Publication year - 2014
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0106668
Subject(s) - medicine , hazard ratio , stage (stratigraphy) , proportional hazards model , retrospective cohort study , surgery , survival analysis , population , single center , adjuvant therapy , lung cancer , cancer , oncology , confidence interval , paleontology , environmental health , biology
Background The aim of this study was to analyze the time-varying pattern of recurrence risk of early-stage (T1a-T2bN0M0) non-small cell lung cancer (NSCLC) after surgery using the hazard function and identify patients who might benefit from adjuvant chemotherapy. Patients and Methods This retrospective study enrolled 994 patients with early-stage NSCLC who underwent radical surgical resection between January 1999 and October 2009. Survival curves were generated using the Kaplan-Meier method, and the annual recurrence hazard was estimated using the hazard function. Results The median recurrence-free survival (RFS) was 8.8 years. The life table survival analysis showed that the 1-year, 3-year, 5-year and 10-year recurrence rates were 82.0%, 67.0%, 59.0% and 48.0%, respectively. Approximately 256 (25.7%) patients experienced relapse [locoregional: 32 (3.2%) and distant: 224 (22.5%)], and 162 patients died from cancer. The annual recurrence hazard curve for the entire population showed that the first major recurrence surge reached a maximum 1.6 years after surgery. The curve subsequently declined until reaching a nadir at 7.2 years. A second peak occurred at 8.8 years. An analysis of clinical-pathological factors demonstrated that this double-peaked pattern was present in several subgroups. Conclusions The presence of a double-peaked pattern indicates that there is a predictable temporal distribution of the recurrence hazard of early-stage NSCLC. The annual recurrence hazard may be an effective method of selecting patients at high risk of recurrence, who may benefit from adjuvant therapy.