Epidemiology, oncologic results and risk stratification model for metachronous peritoneal metastases after surgery for pT4 colon cancers: results from an observational retrospective multicentre long-term follow-up study.

PURPOSE: Metachronous peritoneal metastases (MPM) following a curative surgery procedure for pT4 colon cancer is a challenging condition. Current epidemiological studies on this topic are scarce. METHODS: A retrospective multicentre trial was designed. All consecutive patients who underwent operations to treat pT4 cancers between 2015 and 2017 were reviewed. Demographic, clinical, operative, pathological and oncological follow-up variables were included. MPM were described as any oncological disease at the peritoneum, clearly different from a local recurrence. Univariate and multivariate Cox regression models were constructed. A risk stratification model was created on a cumulative factor basis. According to the calculated hazard ratio (HR), a scoring system was designed (HR < 3, 1 point; HR > 3, 2 points) and a scale from 0 to 6 was calculated for peritoneal disease-free rate (PDF-R). A risk stratification model was also created on the basis of these calculations. RESULTS: Fifty different hospitals were involved, which included a total of 1356 patients. Incidence of MPM was 13.6% at 50 months median follow-up. The strongest independent risk factors for MPM were positive pN stage [HR 3.72 (95% CI 2.56-5.41; p < 0.01) for stage III disease], tumour perforation [HR 1.91 (95% CI 1.26-2.87; p < 0.01)], mucinous or signet ring cell histology [HR 1.68 (95% CI 1.1-2.58; p = 0.02)], poorly differentiated tumours [HR 1.54 (95% CI 1.1-2.2; p = 0.02)] and emergency surgery [HR 1.42 (95% CI 1.01-2.01; p = 0.049)]. In the absence of additional risk factors, pT4 tumours showed 98% and 96% PDF-R in 1-year and 5-year periods based on Kaplan-Meier curves. CONCLUSIONS: Cumulative MPM incidence was 13.6% at 5-year follow-up. The sole presence of a pT4 tumour resulted in high rates of PDF-R at 1-year and 5-year follow-up (98% and 96% respectively). Five additional risk factors different from pT4 status itself were identified as possible MPM indicators during follow-up.

Short-term outcomes of chemoradiotherapy and local excision versus total mesorectal excision in T2-T3ab,N0,M0 rectal cancer: a multicentre randomised, controlled, phase III trial (the TAU-TEM study).

BACKGROUND: The standard treatment of T2-T3ab,N0,M0 rectal cancers is total mesorectal excision (TME) due to the high recurrence rates recorded with local excision. Initial reports of the combination of pre-operative chemoradiotherapy (CRT) and transanal endoscopic microsurgery (TEM) have shown reductions in local recurrence. The TAU-TEM study aims to demonstrate the non-inferiority of local recurrence and the improvement in morbidity achieved with CRT-TEM compared with TME. Here we describe morbidity rates and pathological outcomes. PATIENTS AND METHODS: This was a prospective, multicentre, randomised controlled non-inferiority trial including patients with rectal adenocarcinoma staged as T2-T3ab,N0,M0. Patients were randomised to the CRT-TEM or the TME group. Patients included, tolerance of CRT and its adverse effects, surgical complications (Clavien-Dindo and Comprehensive Complication Index classifications) and pathological results (complete response in the CRT-TEM group) were recorded in both groups. Patients attended follow-up controls for local and systemic relapse. TRIAL REGISTRATION: NCT01308190. RESULTS: From July 2010 to October 2021, 173 patients from 17 Spanish hospitals were included (CRT-TEM: 86, TME: 87). Eleven were excluded after randomisation (CRT-TEM: 5, TME: 6). Modified intention-to-treat analysis thus included 81 patients in each group. There was no mortality after CRT. In the CRT-TEM group, one patient abandoned CRT, 1/81 (1.2%). The CRT-related morbidity rate was 29.6% (24/81). Post-operative morbidity was 17/82 (20.7%) in the CRT-TEM group and 41/81 (50.6%) in the TME group (P < 0.001, 95% confidence interval 42.9% to 16.7%). One patient died in each group (1.2%). Of the 81 patients in the CRT-TEM group who received the allocated treatment, 67 (82.7%) underwent organ preservation. Pathological complete response in the CRT-TEM group was 44.3% (35/79). In the TME group, pN1 were found in 17/81 (21%). CONCLUSION: CRT-TEM treatment obtains high pathological complete response rates (44.3%) and a high CRT compliance rate (98.8%). Post-operative complications and hospitalisation rates were significantly lower than those in the TME group. We await the results of the follow-up regarding cancer outcomes and quality of life.

Long-term outcomes of an acellular dermal matrix for the treatment of complex cryptoglandular anal fistula: a pilot study.

BACKGOUND: Effective, standardized treatments for complex anal fistula (CAF) still represent a clinical challenge. Emerging procedures attempted to achieve the healing rates of fistulotomy whilst preserving sphincter function. Acellular dermal matrix (ADM) used as a plug inserted through the fistulous tract is among newer treatment options. Varying success rates have been reported, most with short-term follow-up. The aim of this study was to report the long-term results of ADM-plug for CAF. METHODS: Retrospective analysis of a prospective database of patients treated with CAF. All consecutive patients presenting at two tertiary centers (Vall d'Hebron University Hospital and Bellvitge University Hospital, Barcelona, Spain) between November 2015 and March 2019 with a single, cryptoglandular CAF were evaluated for treatment with an ADM-plug were included. The primary endpoint was absence of discharge at clinical examination at 12 month follow-up. RESULTS: Twenty-two patients were included [7 women and 15 men, median age 56 (33-74) years]. Most patients had high transsphincteric fistulas (63.6%). The median follow-up was 42 (21-53) months. The 12 month success rate was 68.2%, with an overall healing rate of 59.1%. 77.8% of recurrences occurred within 12 months from surgery. One plug extrusion was observed. No major complications or mortality occurred during the follow-up. Patients did not report any worsening of fecal continence. CONCLUSIONS: This pilot study showed that more than half of patients with CAF could benefit from ADM-plug placement, preserving continence. A minimum follow-up of 12 months is recommended, because most recurrences occur during the first year.

Prognostic factors for complications after loop ileostomy reversal.

BACKGROUND: Defunctioning ileostomy creation and closure are both associated with morbidity. There is little data available about complications after ileostomy closure. The aim of this study was to evaluate morbidity related to loop ileostomy closure (LIC) and to determine if patients with postoperative complications in primary surgery suffer from more postoperative complications during stoma closure. METHODS: This was a retrospective study on prospectively registered consecutive patients undergoing elective LIC in a single centre in Spain between April 2010 and December 2017. Baseline characteristics, postoperative complications after primary surgery and after stoma closure were recorded. Primary surgery included any colorectal resection, elective or urgent associated with a diverting loop ileostomy either as a protective stoma or rescue procedure. A logistic regression model was used to assess the effects of baseline variables and postoperative complications after primary surgery on the existence of postoperative complications related to LIC. RESULTS: Four hundred and twenty-eight patients (288 men, median age 64.5 years [IQR 55.1-72.3 years]) were included in the study, and 37.4%, developed complications after LIC. The most common was paralytic ileus. Only chronic kidney disease (OR 2.31; 95% CI 1.03-5.33, p = 0.043), existence of postoperative complications after primary surgery (OR 2.25; 95% CI 1.41-3.66, p = < 0.001) and ileostomy closure later than 10 months after primary surgery (OR 1.52; 95% CI 1.00-2.33, p = 0.049) were statistically significant in the multivariate analysis. CONCLUSIONS: Patients with chronic kidney disease, those who had any complication after primary surgery and those who had LIC > 10 months after primary surgery have a significantly higher risk of developing postoperative complications.

Analysis of outcomes of emergency general and gastrointestinal surgery during the COVID-19 pandemic.

BACKGROUND: Few surgical studies have provided adjusted comparative postoperative outcome data among contemporary patients with and without COVID-19 infection and patients treated before the pandemic. The aim of this study was to determine the impact of performing emergency surgery in patients with concomitant COVID-19 infection. METHODS: Patients who underwent emergency general and gastrointestinal surgery from March to June 2020, and from March to June 2019 in 25 Spanish hospitals were included in a retrospective study (COVID-CIR). The main outcome was 30-day mortality. Secondary outcomes included postoperative complications and failure to rescue (mortality among patients who developed complications). Propensity score-matched comparisons were performed between patients who were positive and those who were negative for COVID-19; and between COVID-19-negative cohorts before and during the pandemic. RESULTS: Some 5307 patients were included in the study (183 COVID-19-positive and 2132 COVID-19-negative during pandemic; 2992 treated before pandemic). During the pandemic, patients with COVID-19 infection had greater 30-day mortality than those without (12.6 versus 4.6 per cent), but this difference was not statistically significant after propensity score matching (odds ratio (OR) 1.58, 95 per cent c.i. 0.88 to 2.74). Those positive for COVID-19 had more complications (41.5 versus 23.9 per cent; OR 1.61, 1.11 to 2.33) and a higher likelihood of failure to rescue (30.3 versus 19.3 per cent; OR 1.10, 0.57 to 2.12). Patients who were negative for COVID-19 during the pandemic had similar rates of 30-day mortality (4.6 versus 3.2 per cent; OR 1.35, 0.98 to 1.86) and complications (23.9 versus 25.2 per cent; OR 0.89, 0.77 to 1.02), but a greater likelihood of failure to rescue (19.3 versus 12.9 per cent; OR 1.56, 95 per cent 1.10 to 2.19) than prepandemic controls. CONCLUSION: Patients with COVID-19 infection undergoing emergency general and gastrointestinal surgery had worse postoperative outcomes than contemporary patients without COVID-19. COVID-19-negative patients operated on during the COVID-19 pandemic had a likelihood of greater failure-to-rescue than prepandemic controls.

Prevalence of nodal involvement in rectal cancer after chemoradiotherapy.

BACKGROUND: The purpose of this study was to investigate the prevalence of ypN+ status according to ypT category in patients with locally advanced rectal cancer treated with chemoradiotherapy and total mesorectal excision, and to assess the impact of ypN+ on disease recurrence and survival by pooled analysis of individual-patient data. METHODS: Individual-patient data from 10 studies of chemoradiotherapy for rectal cancer were included. Pooled rates of ypN+ disease were calculated with 95 per cent confidence interval for each ypT category. Kaplan-Meier and Cox regression analyses were undertaken to assess influence of ypN status on 5-year disease-free survival (DFS) and overall survival (OS). RESULTS: Data on 1898 patients were included in the study. Median follow-up was 50 (range 0-219) months. The pooled rate of ypN+ disease was 7 per cent for ypT0, 12 per cent for ypT1, 17 per cent for ypT2, 40 per cent for ypT3, and 46 per cent for ypT4 tumours. Patients with ypN+ disease had lower 5-year DFS and OS (46.2 and 63.4 per cent respectively) than patients with ypN0 tumours (74.5 and 83.2 per cent) (P < 0.001). Cox regression analyses showed ypN+ status to be an independent predictor of recurrence and death. CONCLUSION: Risk of nodal metastases (ypN+) after chemoradiotherapy increases with advancing ypT category and needs to be considered if an organ-preserving strategy is contemplated.

When patients are diagnosed with rectal cancer and the tumour grows beyond the rectal wall there is a high risk that the tumour has spread to nearby lymph nodes. This study showed that this relationship between tumour invasion depth and lymph node involvement is similar after treatment with (chemo)radiotherapy. Patients who have tumour cells remaining in the lymph nodes after (chemo) radiotherapy have a worse prognosis than patients who do not have cancer cells remaining in the lymph nodes. When an organ-preserving treatment is considered as an alternative therapy, this should be kept in mind during patient counselling.

European Society of Coloproctology: guidelines for the management of diverticular disease of the colon.

AIM: The goal of this European Society of Coloproctology (ESCP) guideline project is to give an overview of the existing evidence on the management of diverticular disease, primarily as a guidance to surgeons. METHODS: The guideline was developed during several working phases including three voting rounds and one consensus meeting. The two project leads (JKS and EA) appointed by the ESCP guideline committee together with one member of the guideline committee (WB) agreed on the methodology, decided on six themes for working groups (WGs) and drafted a list of research questions. Senior WG members, mostly colorectal surgeons within the ESCP, were invited based on publication records and geographical aspects. Other specialties were included in the WGs where relevant. In addition, one trainee or PhD fellow was invited in each WG. All six WGs revised the research questions if necessary, did a literature search, created evidence tables where feasible, and drafted supporting text to each research question and statement. The text and statement proposals from each WG were arranged as one document by the first and last authors before online voting by all authors in two rounds. For the second voting ESCP national representatives were also invited. More than 90% agreement was considered a consensus. The final phrasing of the statements with < 90% agreement was discussed in a consensus meeting at the ESCP annual meeting in Vienna in September 2019. Thereafter, the first and the last author drafted the final text of the guideline and circulated it for final approval and for a third and final online voting of rephrased statements. RESULTS: This guideline contains 38 evidence based consensus statements on the management of diverticular disease. CONCLUSION: This international, multidisciplinary guideline provides an up to date summary of the current knowledge of the management of diverticular disease as a guidance for clinicians and patients.

Clinical impact of leakage in patients with handsewn vs stapled anastomosis after right hemicolectomy: a retrospective study.

AIM: Anastomotic leakage is a major complication after right hemicolectomy leading to increased morbidity, mortality, length of stay and hospital costs. Previous studies have shown that the type of anastomosis (handsewn or stapled) is a major risk factor for anastomotic leakage. The purpose of this study was to evaluate the clinical impact of anastomotic leakage depending on the type of anastomotic technique (handsewn vs stapled). METHOD: This was an observational, retrospective, cross-sectional study. Data were collected at two major hospitals in Spain from January 2010 to December 2016. Patients had elective right colectomy for cancer with handsewn or stapled ileocolic anastomosis. The main outcome was the grading of postoperative treatments needed to manage anastomotic leakage according to two major classification systems. The other outcomes were demographics, time of hospitalization and death rate. RESULTS: Patients (n = 961) underwent elective surgery for neoplasia of the right colon. Anastomotic leakage was diagnosed in 116 patients (12.07%). Patients with handsewn anastomosis had more Type IIIA surgical complications and received milder treatments than patients with stapled anastomosis (SA) who had more Type IIIB complications and more re-laparotomies (P = 0.004). The clinical impact of anastomotic leakage was significantly more severe (Grade C) in patients with SA than in patients with a handsewn anastomosis (P = 0.007). No differences were found for hospital stay of patients with anastomotic leakage depending on the type of anastomosis (P = 0.275). Death due to anastomotic leakage was similar in both groups. CONCLUSIONS: The clinical impact of anastomotic leakage in patients with handsewn anastomosis is lower than in patients with SA.

Surgical treatment of a colon neoplasm of the splenic flexure: a multicentric study of short-term outcomes.

AIM: The optimal surgical treatment of splenic flexure neoplasm is still not well defined. Extended right hemicolectomy (ERH) and left colic resection (LCR) have been proposed but conclusive evidence concerning postoperative morbidity and oncological results is lacking. The aim of this study was to analyse the short-term outcomes after surgery for splenic flexure cancer with regard to surgical procedure and surgeon's specialty. METHODS: This was a multicentre study on patients who underwent surgery for primary colon cancer of the splenic flexure. RESULTS: From 2004 to 2015, 324 patients fulfilled the criteria for inclusion into the study; 270 (83.4%) had elective surgery while 54 (16.6%) had emergency resection: 158 (48.8%) underwent ERH and 166 (51.2%) LCR; 176 (54.3%) procedures were performed by colorectal surgeons, 148 (46.7%) by general surgeons. In the ERH group a significantly higher rate of emergency operations was carried out (P = 0.005). After elective surgery, no significant differences between ERH and LCR concerning 30-day mortality (3.3% vs 2.0%) and the need for reoperation (10.6% vs 7.4%) were found. Nodal harvesting was significantly higher in the ERH and colorectal surgeon groups in any clinical scenario. At multivariate analysis, age and smoking habit were predictive of the need for reoperation and major morbidity while the general surgeon group showed a higher risk of anastomotic failure (OR = 1.92; P = 0.168). CONCLUSION: We analysed the largest series in literature of curative resections for splenic flexure tumours. The optimal procedure still remains debatable as ERH and LCR appear to achieve comparable short-term outcomes. Surgeon's specialty seems to positively affect patient's outcomes.

Prevention of parastomal hernia after abdominoperineal excision with a prophylactic three-dimensional funnel mesh.

AIM: A prophylactic three-dimensional (3D) funnel mesh using the keyhole technique (intraperitoneal onlay mesh position) in abdominoperineal excision (APR) may significantly decrease the parastomal hernia (PSH) index without increasing morbidity. The aim of this retrospective observational study was to analyse the incidence of PSH and postoperative complications in patients who underwent permanent colostomy with the use of a prophylactic 3D preformed mesh compared with patients without a mesh. METHOD: Patients who underwent an end-colostomy after APR for primary or recurrent rectal cancer in a colorectal surgery unit were divided into two groups: group 1 without a prophylactic mesh and group 2 with a prophylactic synthetic mesh. The main end-point was to analyse the incidence of PSH after a median follow-up of 2.8 years. RESULTS: One hundred and ten patients (64 in group 1 and 46 in group 2, without significant clinical differences) underwent a permanent colostomy after APR. In group 1 70.3% developed a PSH, compared with 13% in group 2 (P < 0.001). Age (especially for patients ≥ 75 years) represented a significant risk factor for PSH. There were no differences in postoperative complications between the groups. CONCLUSION: A prophylactic parastomal 3D mesh using the keyhole technique may reduce the incidence of PSH after permanent colostomy without an increase in postoperative complications.

A propensity-score-matched analysis of laparoscopic vs open surgery for rectal cancer in a population-based study.

AIM: The oncological risk/benefit trade-off for laparoscopy in rectal cancer is controversial. Our aim was to compare laparoscopic vs open surgery for resection of rectal cancer, using unselected data from the public healthcare system of Catalonia (Spain). METHODS: This was a multicentre retrospective cohort study of all patients who had surgery with curative intent for primary rectal cancer at Catalonian public hospitals from 2011 to 2012. We obtained follow-up data for up to 5 years. To minimize the differences between the two groups, we performed propensity score matching on baseline patient characteristics. We used multivariate Cox proportional hazards regression analyses to assess locoregional relapse at 2 years and death at 2 and 5 years. RESULTS: Of 1513 patients with Stage I-III rectal cancer, 933 (61.7%) had laparoscopy (conversion rate 13.2%). After applying our propensity score matching strategy (2:1), 842 laparoscopy patients were matched to 517 open surgery patients. Multivariate Cox analysis of death at 2 years [hazard ratio (HR) 0.65, 95% CI 0.48, 0.87; P = 0.004] and 5 years (HR 0.61, 95% CI 0.5, 0.75; P < 0.001) and of local relapse at 2 years (HR 0.44, 95% CI 0.27, 0.72; P = 0.001) showed laparoscopy to be an independent protective factor compared with open surgery. CONCLUSIONS: Laparoscopy results in lower locoregional relapse and long-term mortality in rectal cancer in unselected patients with all-risk groups included. Studies using long-term follow-up of cohorts and unselected data can provide information on clinically relevant outcomes to supplement randomized controlled trials.

Preoperative oral antibiotic prophylaxis reduces Pseudomonas aeruginosa surgical site infections after elective colorectal surgery: a multicenter prospective cohort study.

BACKGROUND: Healthcare-associated infections caused by Pseudomonas aeruginosa are associated with poor outcomes. However, the role of P. aeruginosa in surgical site infections after colorectal surgery has not been evaluated. The aim of this study was to determine the predictive factors and outcomes of surgical site infections caused by P. aeruginosa after colorectal surgery, with special emphasis on the role of preoperative oral antibiotic prophylaxis. METHODS: We conducted an observational, multicenter, prospective cohort study of all patients undergoing elective colorectal surgery at 10 Spanish hospitals (2011-2014). A logistic regression model was used to identify predictive factors for P. aeruginosa surgical site infections. RESULTS: Out of 3701 patients, 669 (18.1%) developed surgical site infections, and 62 (9.3%) of these were due to P. aeruginosa. The following factors were found to differentiate between P. aeruginosa surgical site infections and those caused by other microorganisms: American Society of Anesthesiologists' score III-IV (67.7% vs 45.5%, p = 0.001, odds ratio (OR) 2.5, 95% confidence interval (95% CI) 1.44-4.39), National Nosocomial Infections Surveillance risk index 1-2 (74.2% vs 44.2%, p < 0.001, OR 3.6, 95% CI 2.01-6.56), duration of surgery ≥75thpercentile (61.3% vs 41.4%, p = 0.003, OR 2.2, 95% CI 1.31-3.83) and oral antibiotic prophylaxis (17.7% vs 33.6%, p = 0.01, OR 0.4, 95% CI 0.21-0.83). Patients with P. aeruginosa surgical site infections were administered antibiotic treatment for a longer duration (median 17 days [interquartile range (IQR) 10-24] vs 13d [IQR 8-20], p = 0.015, OR 1.1, 95% CI 1.00-1.12), had a higher treatment failure rate (30.6% vs 20.8%, p = 0.07, OR 1.7, 95% CI 0.96-2.99), and longer hospitalization (median 22 days [IQR 15-42] vs 19d [IQR 12-28], p = 0.02, OR 1.1, 95% CI 1.00-1.17) than those with surgical site infections due to other microorganisms. Independent predictive factors associated with P. aeruginosa surgical site infections were the National Nosocomial Infections Surveillance risk index 1-2 (OR 2.3, 95% CI 1.03-5.40) and the use of oral antibiotic prophylaxis (OR 0.4, 95% CI 0.23-0.90). CONCLUSIONS: We observed that surgical site infections due to P. aeruginosa are associated with a higher National Nosocomial Infections Surveillance risk index, poor outcomes, and lack of preoperative oral antibiotic prophylaxis. These findings can aid in establishing specific preventive measures and appropriate empirical antibiotic treatment.

Multistate modelling to estimate excess length of stay and risk of death associated with organ/space infection after elective colorectal surgery.

BACKGROUND: Accounting for time-dependency and competing events are strongly recommended to estimate excess length of stay (LOS) and risk of death associated with healthcare-associated infections. AIM: To assess the effect of organ/space (OS) surgical site infection (SSI) on excess LOS and in-hospital mortality in patients undergoing elective colorectal surgery (ECS). METHODS: A multicentre prospective adult cohort undergoing ECS, January 2012 to December 2014, at 10 Spanish hospitals was used. SSI was considered the time-varying exposure and defined as incisional (superficial and deep) or OS. Discharge alive and death were the study endpoints. The mean excess LOS was estimated using a multistate model which provided a weighted average based on the states patients passed through. Multivariate Cox regression models were used to assess the effect of OS-SSI on risk of discharge alive or in-hospital mortality. FINDINGS: Of 2778 patients, 343 (12.3%) developed SSI: 194 (7%) OS-SSI and 149 (5.3%) incisional SSI. Compared to incisional SSI or no infection, OS-SSI prolonged LOS by 4.2 days (95% confidence interval (CI): 4.1-4.3) and 9 days (8.9-9.1), respectively, reduced the risk of discharge alive (adjusted hazard ratio (aHR): 0.36 (95% CI: 0.28-0.47) and aHR: 0.17 (0.14-0.21), respectively), and increased the risk of in-hospital mortality (aHR: 8.02 (1.03-62.9) and aHR: 10.7 (3.7-30.9), respectively). CONCLUSION: OS-SSI substantially extended LOS and increased risk of death in patients undergoing ECS. These results reinforce OS-SSI as the SSI with the highest health burden in ECS.

Correction to: Distal Doppler-guided transanal hemorrhoidal dearterialization with mucopexy versus conventional hemorrhoidectomy for grade III and IV hemorrhoids: postoperative morbidity and long-term outcomes.

The article "Distal Doppler-guided transanal hemorrhoidal dearterialization with mucopexy versus conventional hemorrhoidectomy for grade III and IV hemorrhoids: postoperative morbidity and long-term outcomes", written by L. Trenti, S. Biondo, A. Galvez, A. Bravo, J. Cabrera, E. Kreisler, was originally published electronically on the publisher's internet portal (currently SpringerLink) on [27 April 2017] without open access. With the author(s)' decision to opt for Open Choice the copyright of the article changed on 7 June, 2018 to

Predictive factors for early- and late-onset surgical site infections in patients undergoing elective colorectal surgery. A multicentre, prospective, cohort study.

BACKGROUND: Surgical site infections (SSIs) are the leading cause of healthcare-associated infections in acute care hospitals in Europe. However, the risk factors for the development of early-onset (EO) and late-onset (LO) SSI have not been elucidated. AIM: This study investigated the predictive factors for EO-SSI and LO-SSI in a large cohort of patients undergoing colorectal surgery. METHODS: We prospectively followed-up adult patients undergoing elective colorectal surgery in 10 hospitals (2011-2014). Patients were divided into three groups: EO-SSI, LO-SSI, or no infection (no-SSI). The cut-off defining EO-SSI and LO-SSI was seven days (median time to SSI development). Different predictive factors for EO-SSI and LO-SSI were analysed, comparing each group with the no-SSI patients. FINDINGS: Of 3701 patients, 320 (8.6%) and 349 (9.4%) developed EO-SSI and LO-SSI, respectively. The rest had no-SSI. Patients with EO-SSI were mostly males, had colon surgery and developed organ-space SSI whereas LO-SSI patients frequently received chemotherapy or radiotherapy and had incisional SSI. Male sex (odds ratio (OR): 1.92; P < 0.001), American Society of Anesthesiologists' physical status >2 (OR: 1.51; P = 0.01), administration of mechanical bowel preparation (OR: 0.7; P = 0.03) and stoma creation (OR: 1.95; P < 0.001) predicted EO-SSI whereas rectal surgery (OR: 1.43; P = 0.03), prolonged surgery (OR: 1.4; P = 0.03) and previous chemotherapy (OR: 1.8; P = 0.03) predicted LO-SSI. CONCLUSION: We found distinctive predictive factors for the development of SSI before and after seven days following elective colorectal surgery. These factors could help establish specific preventive measures in each group.