a From Indiana University, Melvin and Bren Simon Cancer Center, and Indiana University School of Nursing, Indianapolis, Indiana; University of Rochester Medical Center, James P. Wilmot Cancer Institute, Rochester, New York; Department of Medicine, University of Chicago, Chicago, Illinois; Department of Medical Oncology, Memorial Sloan Kettering Cancer Center, New York, New York; Division of Urology, Princess Margaret Cancer Centre, Toronto, Ontario; Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Radiation Oncology, Dana-Farber Cancer Institute, and Divisions of Preventive Medicine and Aging, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts; and Department of Oncology, Oslo University Hospital, Norwegian Radium Hospital, Oslo, Norway.
Background: Testicular cancer survivors (TCS) are at significantly increased risk for cardiovascular disease (CVD), with metabolic syndrome (MetS) an established risk factor. No study has addressed clinical and genetic MetS risk factors in North American TCS. Patients and Methods: TCS were aged <55 years at diagnosis and received first-line chemotherapy. Patients underwent physical examination, and had lipid panels, testosterone, and soluble cell adhesion molecule-1 (sICAM-1) evaluated. A single nucleotide polymorphism in rs523349 (5-α-reductase gene, SRD5A2), recently implicated in MetS risk, was genotyped. Using standard criteria, MetS was defined as ≥3 of the following: hypertension, abdominal obesity, hypertriglyceridemia, decreased high-density lipoprotein (HDL) cholesterol level, and diabetes. Matched controls were derived from the National Health and Nutrition Examination Survey. Results: We evaluated 486 TCS (median age, 38.1 years). TCS had a higher prevalence of hypertension versus controls (43.2% vs 30.7%; P<.001) but were less likely to have decreased HDL levels (23.7% vs 34.8%; P<.001) or abdominal obesity (28.2% vs 40.1%; P<.001). Overall MetS frequency was similar in TCS and controls (21.0% vs 22.4%; P=.59), did not differ by treatment (P=.20), and was not related to rs523349 (P=.61). For other CVD risk factors, TCS were significantly more likely to have elevated low-density lipoprotein (LDL) cholesterol levels (17.7% vs 9.3%; P<.001), total cholesterol levels (26.3% vs 11.1%; P<.001), and body mass index ≥25 kg/m2 (75.1% vs 69.1%; P=.04). On multivariate analysis, age at evaluation (P<.001), testosterone level ≤3.0 ng/mL (odds ratio [OR], 2.06; P=.005), and elevated sICAM-1 level (ORhighest vs lowest quartile, 3.58; P=.001) were significantly associated with MetS. Conclusions and Recommendations: Metabolic abnormalities in TCS are characterized by hypertension and increased LDL and total cholesterol levels but lower rates of decreased HDL levels and abdominal obesity, signifying possible shifts in fat distribution and fat metabolism. These changes are accompanied by hypogonadism and inflammation. TCS have a high prevalence of CVD risk factors that may not be entirely captured by standard MetS criteria. Cancer treatment–associated MetS requires further characterization.
Author contributions:Study concept and design: Sesso, Einhorn, Travis. Financial support: Travis. Administrative support: Travis. Provision of study materials or patients: Fung, Feldman, Hamilton, Vaughn, Beard, Einhorn, Travis. Data acquisition: Abu Zaid, Feldman, Cook, Althouse, Travis. Data analysis and interpretation: All authors. Manuscript preparation: All authors. Final approval of manuscript: All authors.
Correspondence: Lois B. Travis, MD, ScD, Indiana University, Melvin and Bren Simon Cancer Center, 535 Barnhill Drive, RT433, Indianapolis, IN 46202. E-mail: firstname.lastname@example.org