8%) received XELOXIRI, 24 (35.8%) XELOX plus cetuximab and 15 (22.4%) FOLFIRI. In 58.2% of patients, four neoadjuvant cycles were administrated. Global median number of administered cycles was 4 [3-6] (Table 2). Eighteen patients (26.8%) reported some side effects to the chemotherapy, which did not contraindicate surgery. The most frequent complication was diarrhea, in six patients followed by neutropenia, in five patients. There was not any differences in complication rates between the three chemotherapy lines administered (P=0.65). Inhibitors,research,lifescience,medical After chemotherapy administration and before surgery, haemoglobin,

leukocytes and platelets mean levels were 11.7×1012/L (8.6-15.3), 5.6×109/L (2.3-13.7) and 225×109/L [72-576] respectively. Median time between the start of chemotherapy and surgery was 107 days, and between the end of chemotherapy and surgery was 29 days. After neoadjuvant treatment, 53 patients (79.1%) achieved hepatic partial response, and 14 (20.9%) stability Inhibitors,research,lifescience,medical of the disease. Table 2 Completion chemotherapy rate All patients underwent colon surgery and within those, eight patients (11.9%) underwent liver surgery simultaneously. Linsitinib Twenty-eight patients (41.8%), underwent liver surgery as a second procedure, and three patients (4.5%) underwent liver Inhibitors,research,lifescience,medical resection

as the first procedure. Twenty-eight patients (41.8%) only underwent primary tumour surgery. In twelve cases (17.9%) a complementary surgery was conducted. Inhibitors,research,lifescience,medical Forty-nine sigmoidectomies/left-hemicolectomies,

14 right hemicolectomies, 2 transverse colon resections and 2 Hartmann operations were performed. In 23 patients (34.3%) a laparoscopic approach was elected. Pathologic characteristics of primary tumour are summarized in Table 3. Seven patients required blood transfusion during their hospital admission: one packed red blood cells (PRBC) on three patients and two PRBC on four patients. Median surgical time was 203 [75-469] minutes and median hospital admission was a total Inhibitors,research,lifescience,medical of 8 [3-29] days. Table 3 Pathologic characteristics of primary tumor In Table 4 the complications reported in the first 30 days after surgery are shown. The complication rate was 16.4%, and no patient presented more than one complication. The morbidity predicted by POSSUM was 58.3%. There was not perioperative GPX6 mortality, despite mortality prediction for P-POSSUM being 5.07%. No differences were observed between the chemotherapy regimen (P=0.72) or the kind of the surgery—simple or combined (P=0.58). After a median follow-up period of 25 months, the median OS was 31 (95% CI: 23-39) months. There were no cases of local relapse. Table 4 Perioperative complications Discussion This study aims to analyze the surgical morbidity secondaty to primary tumor resection after neoadjuvant chemotherapy, in a group of patients diagnosed with stage IV colon adenocarcinoma.