Abstract 5055: Earlier birth cohort, lower BMI, and increased FEV1 are risk factors for cancer in adults with cystic fibrosis
Authors: Doyle John B. , Knotts Rita M. , Keating Claire L. , DiMango Emily A. , Abrams Julian A. 
Published: August 2019

Abstract
Introduction: Adults with cystic fibrosis (CF) have a higher risk of multiple cancer types compared to the general population, and this risk appears to be particularly increased in transplant recipients. However, other risk factors for malignancy have not been well-described. This study assessed patient factors associated with cancer in adults with CF.
Methods: This was a retrospective study of prospectively collected data from the CF Foundation Patient Registry from 1992 - 2015. All adults cancer-free at 18 years of age were followed until either their most recent year in the registry or the year of their cancer diagnosis. Age, sex, CFTR mutation class, history of transplant, birth cohort, and BMI and FEV1 five years prior to cancer diagnosis or most recent registry entry were assessed as predictors of cancer using multivariable logistic regression. Analyses were repeated stratified by history of transplant. Data on cancer type was unavailable in the registry.
Results: Of 26,453 adults with CF, 525 (2.0%) had cancer diagnosed by histology at a mean age of 40.5 (SD=12.8) years. Of cancer patients, 183 (35.1%) were transplant recipients and 302 (64.7%) had a severe CFTR mutation (Class I-III). Among all CF adults, factors independently associated with cancer included lower BMI, higher FEV1, history of transplant, and birth cohort (Table). Among non-transplanted patients, cancer was associated with higher FEV1, unknown mutation class, and birth cohort. Among transplanted patients, cancer was only associated with birth cohort.
Conclusion: A history of transplant, lower BMI, higher FEV1, and earlier birth cohorts are associated with cancer in adults with CF. More recent birth cohorts have lower risks of cancer even after adjustment for age, possibly related to major improvements in CF care. Future studies are warranted to identify risk factors associated with specific cancer types and to better refine cancer screening recommendations in this patient population.
Factors associated with cancer in CF (models include associated variables on univariate analyses)All CF patients (n=12,019)Non-transplanted CF patients (10,790)Transplanted CF patients (n=2,402)Adjusted odds ratio95% confidence intervalAdjusted odds ratio95% confidence intervalAdjusted odds ratio95% confidence intervalAge0.990.98-1.010.980.96-1.001.000.98-1.02Sex (male)0.980.76-1.270.800.59-1.071.160.83-1.62BMI0.950.91-0.99FEV1 percent predicted1.011.00-1.021.011.00-1.02History of transplant2.862.07-3.96N/AN/AN/AN/ABirth cohort&lt;19701.00Referent1.00Referent1.00Referent1970-19740.370.25-0.550.340.21-0.530.500.30-0.841975-19790.270.17-0.410.180.11-0.310.380.21-0.691980-19840.080.05-0.140.070.04-0.140.240.12-0.471985-19890.060.03-0.110.040.02-0.090.120.05-0.311990-19940.010.00-0.050.010.00-0.040.100.03-0.33&gt;1994--0.080.01-0.68CFTR Mutation classClass I-III1.00Referent1.00Referent1.00ReferentClass IV-V0.880.59-1.320.780.50-1.210.760.39-1.49Unknown0.170.54-1.090.660.44-1.001.270.83-1.93
Citation Format: John B. Doyle, Rita M. Knotts, Claire L. Keating, Emily A. DiMango, Julian A. Abrams. Earlier birth cohort, lower BMI, and increased FEV1 are risk factors for cancer in adults with cystic fibrosis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 5055.