Editorial: Obesity and (Thyroid) Cancer
More than 1.9 million new cancer cases will be diagnosed in 2023 in the US, and more than 609,000 cancer deaths (1790 per day) are also expected this year. Obesity is the second most prevalent, preventable and modifiable cancer risk factor after smoking. It has been recognized as an important risk factor in 13 malignancies and can be responsible for 30% to 50% of the cases of liver, gallbladder, esophageal and endometrial cancers. [2, 3] Moreover, obesity increases the risk of pancreatic cancer in 50% to 60% and is currently associated with early-onset colorectal cancer. In obese breast cancer survivors, the risk of lymphedema is higher, and obesity is also associated with a poor quality of life and complications in survivors from other cancers. Although it is well known that radiation and iodine deficiency are established risk factors for thyroid cancer, obesity has also been associated with this malignancy. In fact, it is estimated that an increment of 5-points in the BMI or an increase in 0.1 hip-to-waist ratio, add up a 30% or 14% risk of thyroid cancer in women, respectively. Moreover, thyroid cancer is 1.3 times more likely in obese patients and 1.26 times more likely in overweight ones.
Billions of dollars are spent every year on cancer care costs and thousands of lives are either lost or impaired at a productive age. Also, the incidence and prevalence of obesity is increasing in countries that are seeing their incomes increase, and coincidentally (or not so much), obesity-associated cancers are also on the rise. For instance, the vast majority of new thyroid cancer cases (91%) occur in prosperous countries with the highest Human Development Index (HDI). In the World, the West Pacific region has 48% of the cases of thyroid cancer, whilst only having 25% of the total population. It is calculated that by 2040, the incidence of thyroid cancer and mortality will increase by 30% and 67%, respectively. Paradoxically, the Africa region is projected to experience an increase of 84.3% and 100.3% in incidence and mortality, respectively, likely related to the socioeconomic status and lack of access to quality healthcare. At the personal level, patients with thyroid cancer report having experienced financial burden as a consequence of the diagnosis despite having financial protection, secured income, insurance and high level of education. For instance, in a cost-effective analysis Wang and colleagues demonstrated that for patients diagnosed with papillary thyroid cancer, the cost of surveillance for low-risk patients is US$ 443,456, US$ 987,080 for intermediate-risk patients, and US$ 454,961 for high-risk patients, which translates to a high risk of bankruptcy in this population.
This is just a glimpse of the burden obesity and cancer represent to our society. We are privileged witnesses of the previously unthinkable technological progress our society has made in the last decades. The new methods of cancer screening, diagnosis, precision medicine, personalized treatments, immunotherapy, and minimally invasive surgery are just some fields that presuppose our theoretical advantage in the war on cancer. However, the reality is continuously slapping us on the face demonstrating that all these efforts are still insufficient. I believe the war on cancer not only impacts patients, their families, caregivers, healthcare professionals and the healthcare system, but affects all our civilization. The war on cancer should be a priority task of the entire society. The control of modifiable cancer risk factors such smoking or obesity deserve the focused attention of everyone including the major government institutions. At MCRC we assume our role and are committed as active players in this global fight. But success will depend upon the participation of the community as a whole.
 Cancer Facts & Figures 2023| American Cancer Society. Accessed May 30, 2023.
 Obesity and Cancer Fact Sheet - NCI. Published April 13, 2022. Accessed May 31, 2023.
 Xu M, Jung X, Hines OJ, Eibl G, Chen Y. Obesity and Pancreatic Cancer: Overview of Epidemiology and Potential Prevention by Weight Loss. Pancreas. 2018;47(2):158-162. doi:10.1097/MPA.0000000000000974