The clinical importance of overweight or obesity on tumor recurrence in papillary thyroid carcinoma

Abstract

Background: Obesity is known to common, preventable, and modifiable cause of carcinogenesis. Obesity may be associated with the risk and prognosis of papillary thyroid carcinoma (PTC), but the results of studies are controversial. We studied whether overweight or obesity would be associated with poor prognoses, such as tumor recurrence in PTC patients. Methods: PTC patients at a single institution were retrospectively reviewed. Results: A total of 403 PTC patients (352 women and 51 men; mean age, 48 years) were enrolled. They underwent total thyroidectomy or lobectomy from January 2000 through December 2010. One-hundred forty-eight cases (37%) were categorized as overweight or obese [body mass index (BMI) >25 kg/m2]. I found a significant association between overweight or obesity and multifocality (P=0.006). In multivariate analyses adjusting for poor prognosis factors, such as age, gender, tumor size, and extrathyroid extension (ETE), this association disappeared. There was a significant association between overweight or obesity and tumor recurrence; 13% vs. 5% with and without overweight or obesity, respectively (P=0.008 by log-rank test, median follow-up period: 10.5 years). However, this association was also lost on multivariate analysis adjusting for poor prognosis predictors of recurrence. Conclusions: Overweight or obesity might be associated with poor prognosis factors. However, they might not be associated with tumor recurrences of PTC.