Obesity worsens treatment outcomes in rectal cancer patients: the local resective approach could in fact be more difficult in obese patients due to limited surgical visibility and it has also been reported that high visceral adiposity determines an increased risk of recurrence after chemoradiotherapy neoadjuvant. Bariatric surgery has proved to be the best choice for the treatment of morbid obesity and related comorbidities and in this context, the intragastric balloon (IGB) represents a strategy characterized by a low rate of complications and good results in terms of weight loss.

Therefore, the need to be able to offer obese patients suffering from rectal cancer the possibility of a better recovery perspective, alongside radical oncological surgery and neoadjuvant treatments, also a bariatric surgery such as the positioning of an intragastric balloon.

Epidemiological data show that obesity is associated with a 30-70% increase in the risk of developing rectal cancer; Obesity could also be associated with a worsening of the tumor prognosis, with an increased risk of recurrence and increased mortality. From this point of view, recent studies have shown that a BMI ≥ 30 kg/m2 is associated with higher oncological and functional risks in patients with locally advanced rectal cancer, with lower response rates to neoadjuvant treatment and a less frequent preservation of the anal sphincter.

Obesity also worsens treatment outcomes: the local resective approach could in fact be more difficult in obese patients due to limited surgical visibility and it has also been reported that high visceral adiposity determines an increased risk of recurrence after chemoradiotherapy neoadjuvant. Bariatric surgery has proved to be the best choice for the treatment of morbid obesity and related comorbidities and in this context, the intragastric balloon (IGB) represents a strategy characterized by a low rate of complications and good results in terms of weight loss.

The most recent studies on the subject have shown that IGBs are effective in producing weight loss ranging from 6% to 15% compared to 1% -5% produced by lifestyle interventions alone Therefore, the need to be able to offer obese patients suffering from rectal cancer the possibility of a better recovery perspective (reduction of intra- and peri-operative complications, increased disease-free survival and lower risk of long-term recurrence) is underlined. ), alongside radical oncological surgery and neoadjuvant treatments, also a bariatric surgery such as the positioning of an intragastric balloon.

Inclusion Criteria:

• Patients with locally advanced rectal cancer in clinical stage II-III according to AJCC-UICC 2017 (candidates for neoadjuvant therapy)
• Patients suffering from I, II and III degree obesity at the same time
• Age between 18 and 70 years old
• BMI between 31 and 55 kg/m2
• Non-Smoking
• Candidates, according to AIOM guidelines, for rectal resection surgical procedures
• Candidates, according to SICOB guidelines, for an intragastric balloon placement procedure

Exclusion Criteria:

• Age ≤ 18 or ≥ 70 years
• BMI ≤ 30 or ≥ 59 Kg/m2
• Smoker
• Patients with non-locally advanced rectal cancer, not eligible for neoadjuvant therapy
• Histological positivity to Helicobacter pylori
• Presence of ulcerative lesions on EGD
• Previous bariatric surgery treatments

Obese patients, with locally advanced rectal cancer in clinical stage II-III, candidates for neoadjuvant therapy, who can underwent BIB positioning during neoadjuvant period to obtain weight loss before resective cancer surgery