Journal Thoracic Oncology

Abstracts Journal of Thoracic Oncology • Volume 12 Issue S1 January 2017
alone diagnosis on “neuroendocrine appearing” tumors performs well, but is
improved in most cases by the judicious use of IHC in the diagnosis of SCLC,
where histologic features are equivocal or when the pathologist wants to gain
confidence.
Keywords: SCLC, Pathology, Reproducibility, Immunohistochemistry
PUB016 A MULTI-NATIONAL COHORT VALIDATION OF PROCEDURE–
SPECIFIC NOMOGRAMS TO PREDICT RECURRENCE FOR SMALL
LUNG ADENOCARCINOMAS
Sarina Bains 1 , Takashi Eguchi 1 , Arne Warth 2 , Yi-Chen Yeh 3 , Jun-Ichi Nitadori 4 ,
Kaitlin Woo 5 , Teh Ying Chou 3 , Hendrik Dienemann 6 , Thomas Muley 7 , Jun
Nakajima 4 , Aya Shinozaki-Ushiku 8 , Yu-Chung Wu 9 , Kyuichi Kadota 10 , William
Travis 11 , Kay See Tan 5 , David Jones 1 , Prasad Adusumilli 1
1 Thoracic Service, Department of Surgery, Memorial Sloan Kettering Cancer
Center, New York/NY/United States of America, 2 Institute of Pathology,
Heidelberg University Hospital, Heidelberg/Germany, 3 Department of Pathology
and Laboratory Medicine, Taipei Veterans General Hospital, Taipei/Taiwan,
4 Department of Thoracic Surgery, The University of Tokyo Hospital, Tokyo/Japan,
5 Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New
York/NY/United States of America, 6 Department of Thoracic Surgery, Thoraxklinik
at Heidelberg University Hospital, Heidelberg/Germany, 7 Translational Research
Unit (Stf), Translational Lung Research Center Heidelberg (Tlrc), Member of the
German Center for Lung Research (Dzl), Thoraxklinik at Heidelberg University
Hospital, Heidelberg/Germany, 8 Department of Pathology, The University of Tokyo
Hospital, Tokyo/Japan, 9 Department of Surgery, Taipei Veterans General Hospital,
Taipei/Taiwan, 10 Department of Diagnostic Pathology, Kagawa University, Kagawa/
NY/Japan, 11 Dept of Pathology, Memorial Sloan Kettering Cancer Center, New York/
NY/United States of America
Background: The goal of this study was to construct and validate procedure–
specific nomograms, using competing risk analysis, to predict recurrence
following resection for lung adenocarcinoma (LADC) ≤2 cm. Methods:
Nomogram development was performed using an internal cohort (N=909) of
patients who underwent R0 resection for small LADC at our institution (Table
1), and external validation was conducted using cohorts (N=708) from Japan,
Taiwan, and Germany. Cumulative incidence of recurrence (CIR) was assessed,
treating death without recurrence as a competing risk. Nomograms for
5-year-CIR were developed using significant prognostic factors from
multivariable analyses and were evaluated internally using bootstrap
validation. The predictive accuracy of the nomograms was measured using a
concordance index (C-index). Results: Multivariable analyses identified six
independent risk factors with the highest predictive accuracy for CIR in both
the LO (lobectomy) and LR (limited resection) groups (Table 2). These variables
were used to develop two nomograms with C-index of 0.747 for LO and 0.748
for LR. The two nomograms were validated externally with high accuracy
(C-index of 0.710 for LO and 0.796 for LR).Conclusion: The two procedure–
specific nomograms with high C-indices can be used to predict recurrence and,
thereby, better prognosticate and stratify patients with resected small LADC
by outcomes.
Keywords: Nomogram, STAS, Adenocarcinoma, competing risk
PUB017 MINIMALLY INVASIVE LOBECTOMY IS ASSOCIATED WITH
LOWER NONCANCER MORTALITY IN ELDERLY: A PROPENSITY-
SCORE MATCHED ANALYSIS
Boris Hristov 1 , Takashi Eguchi 1 , James Isbell 1 , Bernard Park 1 , Kay See Tan 2 ,
Valerie Rusch 1 , David Jones 1 , Prasad Adusumilli 1
1 Thoracic Service, Department of Surgery, Memorial Sloan Kettering Cancer Center,
New York/NY/United States of America, 2 Epidemiology and Biostatistics, Memorial
Sloan Kettering Cancer Center, New York/NY/United States of America
Background: Two-thirds of the patients with non-small cell lung cancer
(NSCLC) are elderly (≥65 years). As age increases, the risk of competing events,
such as noncancer death, increases. The aim of this study is to investigate
cancer- and noncancer-specific mortality following lobectomy by minimally
invasive surgery (MIS, includes VATS and robot-assisted resections) versus
thoracotomy in elderly patients with NSCLC. Methods: Of 2208 patients
who underwent curative-intent lobectomy for pStage I-III NSCLC without
induction therapy (2000-2012), 1458 patients (66%) were ≥65 years of age
and included in the analysis. Of these, 466 patients underwent MIS and
992 underwent thoracotomy. Propensity-score matching was performed
to identify pairs of thoracotomy and MIS patients with comparable clinical
characteristics including types of comorbidities, pulmonary function,
pathological stage, tumor size, and year of surgery. Association between
surgical approach (MIS vs. thoracotomy) and cause-specific mortality analysis
was performed using competing risks approach: Gray’s test to compare CID
curves, and Fine and Gray’s test to quantify the effects of surgical approach.
Results: Following propensity matching of patients who underwent
thoracotomy (N=366) versus MIS (N=366), there were statistically significant
differences in length of stay (p