Obesity, especially its clinically severe form, has been linked to the occurrence of numerous serious diseases. Obesity and cancer are now two closely related concepts as obese people have an increased chance of developing neoplasms.

How is obesity linked to cancer? How can neoplasms whose appearance is favored by obesity be prevented? The above questions are answered by Dr. Charalambos Spyropoulos, General Surgeon, Director of the 3rd Surgical Clinic and Department of Minimally Invasive Surgery of the Digestive System, Obesity and Diabetes of the Metropolitan General, Secretary General of the Hellenic Obesity Surgery Society (HEXEP):

Obesity as a disease

Obesity is characterized by the increased deposition of fat in the human body, affecting particularly negatively the overall health of the person. A person with a body mass index (BMI) over 30 is considered obese, while someone with a body mass index over 35 is considered clinically severely obese. The etiology of obesity is multifactorial:

• Poor diet
• Reduced physical exercise
• Excessive calorie intake
• Genetic load
• Hormonal disorders

Obesity: Harbinger of serious diseases

Obesity, apart from the autonomous burden it causes on the human body, is related to the progressive appearance of numerous diseases (obesity co-morbidities):

• Type 2 diabetes
• Arterial hypertension
• Dyslipidemia
• Gastroesophageal reflux disease
• Cardiovascular events
• Respiratory problems
• Malignancies

The association of obesity with carcinogenesis is now well established. The appearance of neoplasms in chronically obese individuals may concern various systems and organs of the human body, such as:

• Colon and rectum
• Esophagus
• Stomach
• Breast
• Endometrium
• Kidney
• Protector

Obesity and cancer

Excess body weight and obesity are a major cause of neoplasms. The International Agency for Research on Cancer (IARC) has pointed out that 40% of neoplasms are the result of increased body weight. The pathophysiological mechanisms of carcinogenesis are the subject of continuous study, however the following are considered to be the most prevalent:

• Chronic inflammation: Obesity and increased visceral fat deposition are characterized by the presence of a chronic inflammatory state in the human body, due to the release of numerous hormonal mediators. This chronic inflammatory condition is a precursor pathogenetic feature of various neoplasms.
• Insulin resistance and hyperinsulinemia: Increased levels of insulin due to resistance to its action are a characteristic feature of obesity and are associated with an increased incidence of gastrointestinal cancers.
• Chronic oxidative stress.
• Modification of the intestinal microbiome: Obesity is characterized by a modification of the intestinal microbial colonization that leads to the secretion of toxic and potentially carcinogenic metabolites.

Metabolic surgery prevents cancer

Treating obesity is of paramount importance to prevent the occurrence of obesity-related cancers. Weight loss can and should be achieved by adopting healthy eating patterns and lifestyle changes:

• Improving nutrition
• Daily exercise
• Positive psychology
• Stable sleep

In more serious cases, however, especially in long-term obesity with the presence of characteristics of metabolic syndrome, the application of conservative treatment alone usually does not bring about the desired results.

“Surgical treatment is the most powerful therapeutic approach in cases of clinically severe obesity. The modern therapeutic quiver includes special techniques of metabolic surgery which, apart from other beneficial effects, lead to a statistically significant reduction in the incidence of cancer. Metabolic surgery has proven to increase the long-term survival expectancy of obese patients, reducing mortality from the co-morbidities of obesity as well as the occurrence of malignancies”, concludes Dr. Spyropoulos.