| Severe obesity has been known to be associated | | | | was 70 percent lower than the second group. The |
| with life threatening morbidities including Type 2 | | | | study group also reported a significantly lower |
| diabetes, arthritis, asthma, sleep apnea, | | | | incidence of other malignancies in the first group. |
| hypertension and heart disease. | | | | Given that obesity affects the body in various |
| Epidemiological data have consistently | | | | ways, a single hypothesis cannot fully explain the |
| demonstrated that there is an increasing evidence | | | | result of weight loss surgery on the incidence of |
| of a positive correlation between increased body | | | | colorectal cancer. A possible explanation is that |
| weight and malignancies of the breast, pancreas, | | | | excess body fat is responsible for hormonal |
| ovaries, esophagus and the colon. In fact, | | | | imbalances which constitute a major risk factor |
| oncologists even suggest a more aggressive | | | | for colorectal malignancies. |
| screening for cancers in the obese: especially for | | | | The decrease in body weight, as well the increase |
| breast, uterine, and colorectal cancers. | | | | in the distal small intestine hormone peptide YY |
| So, is there an association between colorectal | | | | (PYY), and glucagon-like peptide 1 (GLP-1), which |
| cancer and weight loss surgery? | | | | are secreted by intestinal L cells consequent to |
| Researchers believe that dysregulation of energy | | | | weight loss surgery result in an altered metabolic |
| homeostasis is associated with colorectal | | | | milieu. The chronic low grade inflammation known |
| carcinogenesis, with insulin resistance (the impaired | | | | to be associated with obesity decreases, as does |
| ability to normalize plasma glucose levels inspite of | | | | the oxidative stress, resulting in protection from |
| adequate insulin reserves) being the core of these | | | | malignancies, including those of the colon. |
| pathogenesis. The alteration of the patient's | | | | It is therefore difficult to attribute the decreased |
| hormonal milieu due to weight loss therefore may | | | | risk for cancer to weight loss alone and multiple |
| result in a lower incidence of these cancers. | | | | factors both pre- and post-bariatric surgery have |
| In a study of 1482 women with severe obesity, it | | | | to be evaluated before reaching a conclusion. |
| was found that those who had not undergone | | | | Another important consideration when considering |
| bariatric surgery had a significantly higher cancer | | | | the impact of weight loss surgery on cancer risk |
| diagnosis rate (5.8 versus 3.6 percent) than did | | | | is that diet and exercise have not proven very |
| the patients who had undergone bariatric surgery. | | | | effective strategies for weight loss in the |
| There is clinical evidence to suggest that obese | | | | morbidly obese. |
| women who undergo bariatric surgery experience | | | | Researchers therefore maintain that even though |
| as much as a 42 percent drop in the relative risk | | | | there are no randomized case control trials to |
| for developing a malignancy. | | | | suggest that sustained weight loss through |
| In a retrospective study, researchers compared | | | | bariatric surgery decreases the risk of death |
| 1,035 morbidly obese patients who underwent | | | | from colorectal cancer, especially in men, who are |
| bariatric surgery with 5,746 patients with the | | | | most at risk for this, weight loss surgery could be |
| same weight profile who did not undergo the | | | | protective for colorectal cancer as well as other |
| operation. They found that the incidence of | | | | obesity related malignancies. |
| diagnosis of colorectal cancer in the first group | | | | |