Postoperative morbidity following Hartmann's procedure in comparison to anterior resection and abdominoperineal resection for rectal cancer-a population-based study.

AIM: There is ongoing controversy regarding the extent to which Hartmann's procedure (HP) should be used in rectal cancer treatment. This study was designed to investigate 30-day postoperative morbidity and mortality following HP, anterior resection (AR) and abdominoperineal resection (APR) for rectal cancer using a national registry. METHODS: All patients operated for rectal cancer, tumour height 5-15 cm, between the years 2010 and 2017, were identified through the Swedish colorectal cancer registry. RESULTS: A total of 8476 patients were included: 1210 (14%) undergoing HP, 5406 (64%) AR and 1860 (22%) APR. HP was associated with an increased risk of intra-abdominal infection (OR 1.7, CI 1.26-2.28, P = 0.0004) compared to AR and APR, while APR was related to an increased risk of overall complications (OR 1.18, CI 1.01-1.40, P = 0.040). No significant difference was observed in the rate of reoperations and readmissions between HP, AR and APR, and type of surgical procedure was not a risk factor for 30-day mortality. Findings from a subgroup analysis of patients with a tumour 5-7 cm from the anal verge revealed that HP was not associated with increased risk for complications or 30-day mortality. CONCLUSIONS: For patients where AR is not appropriate HP is a valid alternative with a favourable outcome. APR was associated with the highest overall 30-day complication rate.

Corrigendum: Surgical decision-making following neoadjuvant immunotherapy for dMMR rectal cancer; case reports and review of the literature.

Corrigendum for article: DOI: 10.1080/0284186X.2023.2281005.

Hartmann's procedure in rectal cancer surgery is often an intraoperative decision: a retrospective multicenter study.

PURPOSE: This study aimed to investigate patient-related factors predicting the selection of rectal cancer patients to Hartmann's procedure as well as to investigate how often, and on what grounds, anterior resection is intraoperatively changed to Hartmann's procedure. METHODS: Prospectively collected data from the Swedish Colorectal Cancer Registry regarding patients with rectal cancer operated upon from January 1 2007 to June 30 2017 in the county of Skåne were retrospectively reviewed. Data were expanded with further details from medical charts. A univariable analysis was performed to investigate variables associated with unplanned HP and significant variables included in a multivariable logistic regression analysis. RESULTS: Altogether, 1141 patients who underwent Hartmann's procedure (275 patients, 24%), anterior resection (491 patients, 43%), or abdominoperineal resection (375 patients, 33%) were included. Patients undergoing Hartmann's procedure were significantly older and had more frequently comorbidity. The decision to perform Hartmann's procedure was made preoperatively in 209 (76%) patients, most commonly because of a comorbidity (27%) or oncological reasons (25%). Patient preference was noted in 8% of cases. In 64 cases (23%), the decision was made intraoperatively, most often due to anastomotic difficulties (60%) and oncological reasons (22%). Anastomotic difficulties were most often reported due to technical difficulties, a low tumor or neoadjuvant radiotherapy. Male gender was a significant risk factor for undergoing unplanned Hartmann's procedure. CONCLUSIONS: The decision to perform Hartmann's procedure was frequently made intraoperatively. Hartmann's procedure should be considered and discussed preoperatively in old and frail patients, especially in the presence of mid-rectal cancer and/or male gender, since these factors increase the risk of intraoperative anastomotic difficulties.

Tumour deposits in colon cancer predict recurrence and reduced survival in a nationwide population-based study.

BACKGROUND: Tumour deposits are suggested to impact prognosis in colon cancer negatively. This study assessed the impact of tumour deposits on oncological outcomes. METHODS: Data from the Swedish Colorectal Cancer Registry for patients who underwent R0 abdominal surgery for TNM stage I-III colon cancer between 2011 and 2014 with 5-year follow-up were analysed with multivariable analysis. Patients were categorized for their tumour deposit status and compared for the local recurrence and distant metastasis rates and 5-year survivals (overall and relative). Subgroup analyses were performed according to the nodal disease status. RESULTS: Of 8146 stage I-III colon cancer patients who underwent R0 resection, 8014 patients were analysed (808 tumour deposits positive, 7206 tumour deposits negative). Patients with tumour deposits positive tumours had increased local recurrence and distant metastasis rates (7.2 versus 3.0 per cent; P < 0.001 and 33.9 versus 12.0 per cent; P < 0.001 respectively) and reduced 5-year overall and relative survival (56.8 per cent versus 74.9 per cent; P < 0.001 and 68.5 versus 92.6 per cent; P < 0.001 respectively). In multivariable analysis, tumour deposits moderately increased the risks of local recurrence and distant metastasis (hazard ratio 1.50, 95 per cent c.i. 1.09 to 2.07; P = 0.013 and HR 1.91, 95 per cent c.i. 1.64 to 2.23; P < 0.001 respectively) and worse 5-year overall and relative survival (hazard ratio 1.60, 95 per cent c.i. 1.40 to 1.82; P < 0.001 and excess hazard ratio 2.24, 95 per cent c.i. 1.81 to 2.78; P < 0.001 respectively). Subgroup analysis of N stages found that N1c patients had worse outcomes than N0 for distant metastasis and relative survival. For patients with lymph node metastases tumour deposits increased the risks of distant metastasis and worse overall and relative survival, except for N2b patients. CONCLUSION: Tumour deposits negatively impact the prognosis in colon cancer and must be considered when discussing adjuvant chemotherapy.

Adverse impact of tumor deposits in lymph node negative rectal cancer - a national cohort study.

PURPOSE: This study aimed to investigate the prognostic effect of tumor deposits (TDs) in lymph node negative rectal cancer. METHODS: Patients who had undergone surgery for rectal cancer with curative intention between 2011 and 2014 were extracted from the Swedish Colorectal Cancer Registry. Patients with positive lymph nodes, undisclosed TD status, stage IV disease, non-radical resections, or any outcome (local recurrence (LR), distant metastasis (DM) or mortality) within 90 days after surgery were excluded. TDs status was based on histopathological reports. Cox-regression analyses were used to examine the prognostic impact of TDs on LR, DM, and overall survival (OS) in lymph node-negative rectal cancer. RESULTS: A total of 5455 patients were assessed for inclusion of which 2667 patients were analyzed, with TDs present in 158 patients. TD-positive patients had a lower 5-year DM-free survival (72.8%, p < 0.0001) and 5-year overall survival (75.9%, p = 0.016), but not 5-year LR-free survival (97.6%) compared to TD-negative patients (90.2%, 83.1% and 95.6%, respectively). In multivariable regression analysis, TDs increased the risk of DM [HR 4.06, 95% CI 2.72-6.06, p < 0.001] and reduced the OS [HR 1.83, 95% CI 1.35-2.48, p < 0.001]. For LR, only univariable regression analysis was performed which showed no increased risk of LR [HR 1.88, 95% CI 0.86-4.11, p = 0.11]. CONCLUSION: TDs are a negative predictor of DM and OS in lymph node-negative rectal cancer and could be taken into consideration when planning adjuvant treatment.

Circumferential Resection Margin is Associated With Distant Metastasis After Rectal Cancer Surgery: A Nation-wide Population-based Study Cohort.

OBJECTIVE: To evaluate circumferential resection margin (CRM) as a risk factor for distant metastasis (DM) in rectal cancer. SUMMARY OF BACKGROUND DATA: The treatment of rectal cancer has evolved over the last decades. Surgical radicality is considered the most important factor in preventing recurrences including local and distant. CRM ≤1.0 mm is considered to increase recurrence risk. This study explores the risk of DM in relation to exact CRM. METHODS: All patients treated with abdominal resection surgery for rectal cancer between 2005 and 2013 in Sweden were eligible for inclusion in this retrospective study. Primary endpoint was DM. RESULTS: Twelve thousand one hundred forty-six cases were identified. Eight thousand five hundred ninety-three cases were analyzed after exclusion. Seven hundred seventeen (8.6%) patients had CRM ≤1.0mm and 7577 (91.4%) patients had CRM >1.0 mm. DM recurrence rate at 5 years was 42.1% (95% CI 32.5-50.3), 31.5% (95% CI 27.3-35.5), 25.8% (95% Confidence Interval (CI) 16.2-34.4), and 19.5% (95% CI 18.5-19.5) when CRM was 0.0 mm, 0.1 to 1.0 mm, 1.1 to 1.9 mm, and CRM ≥2mm, respectively. Multivariable analysis revealed higher DM risk in CRM 0.0-1.0 mm versus >1.0 mm (hazard ratio 1.30, 95% CI 1.05-1.60; P = 0.015). No significant difference in DM risk in CRM 1.1-1.9 mm versus ≥2.0 mm (hazard ratio 0.66, 95% CI 0.34-1.28; P = 0.224) could be detected. CONCLUSIONS: The risk of DM decreases with increasing CRM. Moreover, CRM ≤1.0 mm is a significant risk factor for DM. Thus, CRM is a dominant factor when discussing risk of DM after rectal cancer surgery.

Negative Prognostic Impact of Tumor Deposits in Rectal Cancer: A National Study Cohort.

OBJECTIVE: To investigate whether tumor deposits (TDs) in rectal cancer are associated with increased recurrence risk and decreased survival. BACKGROUND: Tumor deposits (TDs) are considered a risk factor for recurrence after colon cancer resection, and the presence of TDs prompts adjuvant chemotherapy. The prognostic relevance of TDs in rectal cancer requires further exploration. METHODS: All patients treated with abdominal resection surgery for rectal cancer in Sweden between 2011 and 2014 were eligible for inclusion in this retrospective cohort study based on prospectively collected data from the Swedish Colorectal Cancer Registry. The primary endpoint was local recurrence or distant metastasis. Secondary outcomes were overall and relative survival. RESULTS: Five thousand four hundred fifty-five patients were identified of which 3769 patients were analyzed after exclusion. TDs were found in 404 (10.7%) patients, including 140 (3.7%) patients with N1c-status. In TD-positive patients, local recurrence and distant metastasis rates at 5 years were 6.3% [95% CI 3.8-8.8%] and 38.9% [95% CI, 33.6-43.5%] compared with 2.7% [95% CI, 2.1-3.3%] and 14.3% [95% CI, 13.1-15.5%] in TD-negative patients. In multivariable regression analysis, the risk of local recurrence and distant metastasis were increased; HR 1.86 [95% CI, 1.09-3.19; P =0.024] and 1.87 [95% CI, 1.52-2.31; P =<0.001], respectively. Overall survival at 5 years was 68.8% [95% CI, 64.4-73.4%] in TD-positive patients and 80.7% [95% CI, 79.4-82.1%] in TD-negative patients. pN1c-patients had similar outcomes regarding local recurrence, distant metastasis, and survival as pN1a-b stage patients. TD-positive pN1a-b patients had significantly worse outcomes whereas TDs did not affect outcomes in pN2a-b patients. CONCLUSION: This study suggests that TDs have a negative impact on the prognosis in rectal cancer. Thus, efforts should be made to diagnose TD-positive rectal cancer patients preoperatively.

Muscle mass and quality as predictors for complications, recurrence and length of hospital stay in acute uncomplicated diverticulitis: a retrospective cohort study.

OBJECTIVES: The aim of this study was to investigate the potential correlation between muscle mass/muscle quality and risk of complications or recurrence in patients presenting with acute uncomplicated diverticulitis. It was also to study if low muscle mass/quality correlated to prolonged hospital stay. MATERIALS AND METHODS: The study population comprised 501 patients admitted to Helsingborg Hospital or Skåne University Hospital between 1 January 2015 and 31 December 2017, who had been diagnosed with acute uncomplicated diverticulitis and undergone computed tomography upon admission. The scans were used to estimate skeletal muscle mass and muscle radiation attenuation (an indicator for muscle quality). Skeletal muscle index was obtained by adjusting skeletal muscle mass to the patients' height. Values of below the fifth percentile of a normal population were considered low. RESULTS: There were no differences between the patients with normal versus those with low skeletal muscle mass, skeletal muscle index or muscle radiation attenuation regarding risk of complications or recurrence of diverticular disease. However, as only 11 patients had complications, no conclusion as to a potential correlation can be made. Low muscle quality correlated to longer hospital stay, also when adjusting for other potential confounders. CONCLUSIONS: Muscle mass/quality do not seem to serve as predictor of risk for recurrent disease in patients with acute uncomplicated diverticulitis. However, low muscle radiation attenuation was associated with prolonged hospital stay. This indicates that muscle quality, assessed by computed tomography scan, might be used in clinical practise to identify patients at risk of longer hospitalisation.

Low incidence of pelvic sepsis following Hartmann's procedure for rectal cancer: a retrospective multicentre study.

BACKGROUND: Results of previous studies regarding pelvic sepsis after Hartmann's procedure (HP) for rectal cancer have been inconsistent and few studies report the risk factors. This study aimed to investigate the incidence of pelvic sepsis after HP, identify risk factors and describe when as well as how pelvic sepsis was diagnosed and treated. METHODS: Data were collected from the Swedish Colorectal Cancer Registry on all patients undergoing HP for rectal cancer in the county of Skåne from 2007-2017. Patients diagnosed with pelvic sepsis were compared with patients without pelvic sepsis and risk factors for developing pelvic sepsis were analysed in a multivariable model. RESULTS: A total of 252 patients were included in the study, with 149 (59%) males, and a median age of 75 years (range 20-92). Altogether, 27 patients (11%) were diagnosed with pelvic sepsis. Risk factors for developing pelvic sepsis were neoadjuvant radiotherapy (OR 7.96, 95% CI 2.54-35.36) and BMI over 25 kg/m2 (OR 5.26, 95% CI 1.80-19.50). Median time from operation to diagnosis was 21 days (range 5-355) with 11 (40%) patients diagnosed beyond 30 days postoperatively. The majority of cases 19 (70%) were treated conservatively and none needed major surgery. CONCLUSION: Pelvic sepsis occurred in 11% of patients. Neoadjuvant radiotherapy and higher BMI were significant risk factors for developing pelvic sepsis. Forty percent of patients were diagnosed later than 30 days postoperatively and most patients were successfully treated conservatively. Our findings suggest that HP is a valid treatment option for rectal cancer when anastomosis is inappropriate, even in patients receiving neoadjuvant radiotherapy.

Impact of rectal washout on recurrence and survival after anterior resection for rectal cancer.

BACKGROUND: Rectal washout (RW) is routinely performed during anterior resection (AR) for rectal cancer to reduce local recurrence (LR), although is sometimes not performed during minimally invasive surgery (MIS) procedures due to technical challenges and time consumption. The aim was to investigate the impact of RW on the oncological outcome after AR for rectal cancer in a registry cohort. METHODS: Data on patients registered in the Swedish Colorectal Cancer Registry who had undergone elective radical (R0) AR for TNM stage I-III rectal cancer between 2007 and 2017 with a 3-year follow-up were analysed. Multivariable analyses were performed and the primary endpoint was LR at 3 and 5 years after AR. The occurrence of distant metastasis (DM) and overall recurrence (OAR), overall survival, and relative survival were also analysed as a secondary aim. A subgroup analysis was performed for the same outcomes in patients treated with MIS. RESULTS: Out of 6186 patients (1923 with TNM stage I, 1907 with TNM stage II, and 2356 with TNM stage III), RW was performed in 5706 (92.2 per cent). The median age of the cohort was 67 years. RW did not impact the 3-year risk of LR. LR within 5 years occurred in 104 of 4583 patients (2.3 per cent) in the RW group compared with 16 of 408 patients (3.9 per cent) in the no RW group (P = 0.037). In multivariable analysis of the LR risk, the HR was 0.53 (95 per cent c.i. 0.31 to 0.90), favouring RW. There were no differences in rates of DM and OAR, overall survival, and relative survival. A subgroup analysis of the 1410 patients undergoing MIS did not demonstrate any differences between the groups, given, however, the low rate of LR. CONCLUSIONS: RW in AR for rectal cancer does not impact the 3-year oncological outcome; however, after the 5-year follow-up a reduction in LR risk was observed after RW.

Management of acute uncomplicated diverticulitis without antibiotics: compliance and outcomes -a retrospective cohort study.

METHODS: Recent randomized control trials (RCTs) have confirmed that antibiotics in acute uncomplicated diverticulitis (AUD) neither accelerate recovery nor prevent complications or recurrences. A retrospective cohort study was conducted, including all consecutive AUD patients hospitalized 2015- 2018 at Helsingborg Hospital (HH) and Skåne University Hospital (SUS), Sweden. HH had implemented a non-antibiotic treatment protocol in 2014 while SUS had not. Main outcomes were proportion of patients treated with antibiotics, complications, recurrences, and adherence to routinely colon evaluation. RESULTS: A total of 583 AUD patients were enrolled, 388 at SUS and 195 at HH. The diagnosis was CT-verified in 320 (83%) vs. 186 (95%) patients respectively (p < 0.001). Forty-three (11%) and 94 (48%) of patients respectively did not receive antibiotics during hospitalization (p < 0.001). CRP was higher in the antibiotic group compared to the non-antibiotic group, both at admission and peak (90 mg/L vs 65 mg/L; p = 0.016) and (138 mg/L and 97 mg/L; p < 0.001). There were no significant differences in recurrences (22.0% vs. 22.6%; p = 0.87) and complications (2.5% vs. 2.9%; p = 0.77) between the antibiotic/non-antibiotic groups. CONCLUSION: The structured treatment protocol led to reduced antibiotic use and a higher standard of care in terms of CT-verification. Clinicians' compliance to the treatment protocol and best clinical practice was poor and warrants further studies.

Rectal washout during abdominoperineal resection for rectal cancer has no impact on the oncological outcome.

AIM: Intraoperative rectal washout is performed to eliminate exfoliated intraluminal cancer cells and thereby decrease the risk of local recurrence. Rectal washout in abdominoperineal resection has not been studied. The aim of this study was to assess the oncological outcome after rectal washout in abdominoperineal resection for rectal cancer and to find evidence as to whether rectal washout should be performed or not. METHOD: Data for all patients registered in the Swedish Colorectal Cancer Registry who underwent elective surgery with abdominoperineal resection for rectal cancer (TNM Stages I-III) between 2007 and 2013 were analysed using multivariable analysis. RESULTS: No significant differences were shown between the rectal washout group and the no rectal washout group for local recurrence [10/265 (3.8%) vs. 87/2160 (4.0%), p = 0.84], distant metastasis [51/265 (19.2%) vs. 476/2160 (22.0%), p = 0.29] or overall recurrence [53/265 (20.0%) vs. 505/2160 (23.4%), p = 0.21]. In multivariable analysis, rectal washout did not significantly affect the oncological outcome in terms of local recurrence, distant metastasis, overall recurrence or 5-year overall or relative survival. CONCLUSION: Our results do not support routine rectal washout during abdominoperineal resection in order to improve the oncological outcome.

Rectal washout does not increase the complication risk after anterior resection for rectal cancer.

BACKGROUND: To reduce local recurrence risk, rectal washout (RW) is integrated in the total mesorectal excision (TME) technique when performing anterior resection (AR) for rectal cancer. Although RW is considered a safe practice, data on the complication risk are scarce. Our aim was to examine the association between RW and 30-day postoperative complications after AR for rectal cancer. METHODS: Patients from the Swedish Colorectal Cancer Registry who underwent AR between 2007 and 2013 were analysed using multivariable methods. RESULTS: A total of 4821 patients were included (4317 RW, 504 no RW). The RW group had lower rates of overall complications (1578/4317 (37%) vs. 208/504 (41%), p = 0.039), surgical complications (879/4317 (20%) vs. 140/504 (28%), p < 0.001) and 30-day mortality (50/4317 (1.2%) vs. 12/504 (2.4%), p = 0.020). In multivariable analysis, RW was a risk factor neither for overall complications (OR 0.73, 95% CI 0.60-0.90, p = 0.002) nor for surgical complications (OR 0.62, 95% CI 0.50-0.78, p < 0.001). CONCLUSIONS: RW is a safe technique that does not increase the 30-day postoperative complication risk after AR with TME technique for rectal cancer.

Low Incidence of Pelvic Sepsis after Hartmann's Procedure: Radiation Therapy May Be a Risk Factor.

PURPOSE: Hartmann's procedure is a well-established alternative in colorectal surgery when a primary anastomosis is contraindicated. However, the rectal remnant may cause complications. This study was designed to investigate the occurrence of pelvic sepsis after Hartmann's procedure and identify possible risk factors. METHODS: All patients who underwent Hartmann's procedure between 2005 and 2012 were identified by the in-hospital registry. Information about pelvic sepsis and potential preoperative, perioperative, and postoperative risk factors was obtained by review of the medical records. RESULTS: 172 patients were identified (97 females); they were aged 74 ± 11 years. Surgery was performed due to cancer (49%) or diverticulitis (35%) and other benign disease (16%). Rectal transection was carried out anywhere between the pelvic floor and the promontory. Pelvic sepsis developed in 6.4% (11/172) of patients. Pelvic sepsis was associated with preoperative radiotherapy (p = 0.03) and Hinchey grade III and IV (p = 0.02) in those patients who underwent Hartmann's procedure for diverticular disease. CONCLUSION: Hartmann's procedure is a safe operation when an anastomosis is contraindicated since the incidence of pelvic sepsis is low. Preoperative radiotherapy and Hinchey grade III and IV may be risk factors for the development of pelvic sepsis.

Validity of the Swedish Rectal Cancer Registry for patients treated with major abdominal surgery between 1995 and 1997.

BACKGROUND: Founded in 1995, the Swedish Rectal Cancer Registry (SRCR) is frequently used for rectal cancer research. However, the validity of the registry has not been extensively studied. This study aims to validate a large amount of registry data to assess SRCR quality. MATERIAL AND METHODS: The study comprises 906 patients treated with major abdominal surgery registered in the SRCR between 1995 and 1997. SRCR data for 14 variables were scrutinized for validity against the medical records. Kappa's and Kendall's correlation coefficients for agreement between SRCR data and medical records data were calculated for 13 variables. RESULTS: For 11 variables, concerning the tumor, neoadjuvant therapy, the surgical procedure, local radicality and TNM stage, data were missing in 5% or less of the registrations; for the remaining three variables, anastomotic leakage, local and distant recurrence, data were missing in 13-38%. For the variables surgery performed or not and type of surgical procedure, no data were missing. Erroneous registrations were found in less than 10% of all variables; for the variables preoperative chemotherapy and surgery performed or not, all registrations were correct. For the variables concerning neoadjuvant therapy, local radicality according to the surgeon as well as the pathologist and distant metastasis, the false-positive or -negative registrations were equally distributed, and for the variables rectal washout, rectal perforation, anastomotic leakage and local recurrence there was a discrepancy in distribution. The correlation coefficient for 12 variables ranged from 0.82 to 1.00, and was 0.78 for the remaining variable. CONCLUSION: The validity of the SRCR was good for the initial three registry years. Thus, research based on SRCR data is reliable from the beginning of the registry's use.

Ezrin expression in rectal cancer predicts time to development of local recurrence.

PURPOSE: Improved outcome after rectal cancer surgery requires identification of novel risk factors of tumour recurrence in order to personalise therapy, that is, enhanced selection of high-risk patients to additional radiochemotherapy or intensified follow-up. In several tumour types, including colorectal cancer, high expression of the membrane-cytoskeleton linker ezrin has been suggested to impair prognosis but has not yet reached clinical application. We evaluated the expression of ezrin in rectal cancer with a focus on the identification of a marker for local tumour recurrence. METHODS: Immunohistochemical expression of ezrin was analysed in 104 primary rectal cancers from patients who developed local recurrences despite being treated with R0 major abdominal surgery. Time to local recurrence and distant metastasis as well as 5-year overall and cancer-specific survival were used as end points. RESULTS: Ezrin expression was weak in 17% of the tumours, moderate in 62%, and intense in 21%. The time to local recurrence was significantly shorter (p = 0.0004) for patients with tumours showing high ezrin expression. No correlation between ezrin expression and time to distant metastasis was identified. Survival data were similar between groups irrespective of ezrin expression in the primary tumours. CONCLUSIONS: Our findings suggest that increased expression of ezrin may represent a marker of aggressive biological behaviour in rectal cancer. Although further validation is needed, ezrin may represent a relevant marker for personalised treatment of rectal cancer with respect to risk of local recurrence after R0 surgery.

Oncological outcome after incidental perforation in radical rectal cancer surgery.

PURPOSE: Identification of risk factors of poor oncological outcome in rectal cancer surgery is of utmost importance. This study examines the impact of incidental perforation on the oncological outcome. METHODS: Using the Swedish Rectal Cancer Registry, patients were selected who received major abdominal surgery for rectal cancer between 1995 and 1997 with registered incidental perforation. A control group was also selected for analysis of the oncological outcome after 5-year follow-up. Multivariate analysis was performed. Registry data were validated, and additional data were supplemented from medical records. RESULTS: After validation and exclusion of non-radically operated patients, 118 patients with incidental perforation and 155 controls in TNM stages I-III were included in the analysis. The rate of local recurrence (LR) [20% (23/118) vs. 8% (12/155) (p = 0.007)] was significantly higher among patients with perforation, whereas the rates of distant metastasis [27% (32/118) vs. 21% (33/155) (p = 0.33)] and overall recurrence (OAR) [35% (41/118) vs. 25% (38/155) (p = 0.087)] were not significantly different between the groups. Overall as well as cancer-specific 5-year survival rates were significantly reduced for the patients with perforation [44 vs. 64% (p = 0.002) and 66 vs. 80% (p = 0.026), respectively]. In the multivariate analysis, perforation was a significant risk factor of increased rates of LR and OAR as well as reduced 5-year overall and cancer-specific survival. CONCLUSIONS: Incidental perforation in rectal cancer surgery is an important risk factor of poor oncological outcome and should be considered in the discussion concerning postoperative adjuvant treatment as well as the follow-up regime.