Type 2 diabetes can increase the risk for hepatocellular carcinoma and other malignancies in patients with chronic HCV, according to recent results.
In a retrospective cohort study, researchers observed the incidence of malignancies during a mean follow-up of 8.1 years among 4,302 Japanese patients with chronic HCV who had undergone prior interferon [IFN] therapy. All participants had no malignancies, had received IFN therapy between 1 month and 1 year and were aged 30 to 80 years at enrollment.
Malignancy occurred in 606 patients, including 393 incidents of HCC, which had cumulative development rates of 4.3%, 10.5% ,19.7% and 28% after 5, 10, 15 and 20 years, respectively. Other malignancies — including stomach, colon, lung, pancreatic, prostate and breast cancers — had cumulative development rates of 2.4%, 5.1%, 9.8% and 18% for 5, 10, 15 and 20 years, respectively.
Factors associated with HCC development included the presence of cirrhosis (n=433 patients, HR=5.01; 95% CI, 3.92-6.40), a lack of sustained virological response during interferon therapy (n=2,402 patients; HR=4.93; 95% CI, 3.53-6.89) and type 2 diabetes (T2DM) (n=267 patients; HR=1.73; 95% CI, 1.30-2.30). Investigators noted that the risk for HCC decreased among patients with diabetes and mean HbA1c levels less than 7.0% (HR=0.56; 95% CI, 0.33-0.89).
The presence of non-HCC malignancies was associated with advanced age (HR=2.19, 1.84-2.62 for every 10-year increase), heavier smoking (20 or more pack-years) (HR=1.89, 1.41-2.53 compared to fewer than 20 pack-years) and T2DM (HR=1.70, 1.14-2.53). In particular, T2DM was significantly associated with pancreatic cancer (HR=3.75, 1.02-13.88), and also had a tendency to increase the risk for gastric cancer (HR=2.29, 0.95-5.52) (95% CI for all).
“The present study shows several findings with regard to the development incidence and predictive factors for total malignancies after IFN therapy for HCV patients,” the researchers wrote. “T2DM causes an approximately 1.7-fold enhancement in the development of HCC and malignancies other than HCC after IFN therapy. Additionally, in T2DM patients, maintaining mean HbA1c levels of [less than] 7.0% during follow-up reduced the development of HCC.”