So far, the impact of sarcopenia has been analysed only in patients undergoing traditional surgical procedures (laparotomy) or those with metastatic spread. As the ERAS protocol combined with minimally invasive access decreases postoperative metabolic disorders, it seems possible that it can limit the deleterious impact of sarcopenia as well. The aim of this study was to investigate whether the use of ERAS protocol in colorectal cancer patients influences the postoperative risk due to sarcopenia.

The prospective observation with post-hoc analysis of 171 consecutive colorectal cancer patients was performed. In all patients 16-item ERAS protocol was applied.

Contrast-enhanced CT scan was performed preoperatively. From each scan one CT image at the level of L3 vertebra was transferred in Digital Imaging and Communications in Medicine format (DICOM) and anonymised. Firstly, the threshold range between -29 and +150 Hounsfield units was set to semi-automatically outline muscle areas, - 150 to - 50 was used for visceral adipose tissue areas, and -190 to -30 was used for subcutaneous and intermuscular adipose tissue areas. Secondly, the software calculated the surface area (cm2) of each tissue. The L3 skeletal muscle area (rectus abdominis, external and internal obliques, transversus abdominis, quadratus lumborum, psoas, erector spinae) normalized for patient height was used to calculate skeletal muscle index (SMI) (cm2/m2).

According to Martin et al. sarcopenia was defined as a SMI <41 cm2/m2 in women, <43 cm2/m2 in men with a BMI <25 kg/m2, and <53 cm2/m2 in men with a BMI >25 kg/m2 (10). To assess for myosteatosis the mean radiodensity of a L3 psoas muscle was measured. The cut-off for patients with BMI <25 kg/m2 was <41 Hounsfield units and <33 Hounsfield units for patients with BMI ≥25 kg/m2.

For the purposes of further analysis the entire group of patients was divided into subgroups depending on the presence of sarcopenia or myosteatosis.

Inclusion Criteria:

• confirmed adenocarcinoma of colon or rectum
• complete preoperative radiology assessment with abdominal CT scan
• laparoscopic resection
• perioperative care according to ERAS principles

Exclusion Criteria:

• unavailability of a preoperative abdominal CT scan (within 30 days prior surgery)
• emergency or initially open surgery
• patients treated with endoscopic techniques: transanal endoscopic microsurgery (TEM), transanal total mesorectal excision (TaTME)
• concomitant inflammatory bowel diseases.

The analysis included prospectively collected data from consecutive patients electively operated for colorectal cancer in the years 2014-2015. All patients were operated using laparoscopic surgery, and the perioperative care was based on pre-established ERAS protocol consisting of 13 items