National differences in implementation of minimally invasive surgery for colorectal cancer and the influence on short-term outcomes.

BACKGROUND: The timing and degree of implementation of minimally invasive surgery (MIS) for colorectal cancer vary among countries. Insights in national differences regarding implementation of new surgical techniques and the effect on postoperative outcomes are important for quality assurance, can show potential areas for country-specific improvement, and might be illustrative and supportive for similar implementation programs in other countries. Therefore, this study aimed to evaluate differences in patient selection, applied techniques, and results of minimal invasive surgery for colorectal cancer between the Netherlands and Sweden. METHODS: Patients who underwent elective minimally invasive surgery for T1-3 colon or rectal cancer (2012-2018) registered in the Dutch ColoRectal Audit or Swedish ColoRectal Cancer Registry were included. Time trends in the application of MIS were determined. Outcomes were compared for time periods with a similar level of MIS implementation (Netherlands 2012-2013 versus Sweden 2017-2018). Multilevel analyses were performed to identify factors associated with adverse short-term outcomes. RESULTS: A total of 46,095 Dutch and 8,819 Swedish patients undergoing MIS for colorectal cancer were included. In Sweden, MIS implementation was approximately 5 years later than in the Netherlands, with more robotic surgery and lower volumes per hospital. Although conversion rates were higher in Sweden, oncological and surgical outcomes were comparable. MIS in the Netherlands for the years 2012-2013 resulted in a higher reoperation rate for colon cancer and a higher readmission rate but lower non-surgical complication rates for rectal cancer if compared with MIS in Sweden during 2017-2018. CONCLUSION: This study showed that the implementation of MIS for colorectal cancer occurred later in Sweden than the Netherlands, with comparable outcomes despite lower volumes. Our study demonstrates that new surgical techniques can be implemented at a national level in a controlled and safe way, with thorough quality assurance.

Family history of colorectal cancer and survival: a Swedish population-based study.

OBJECTIVES: A family history of colorectal cancer (CRC) is an established risk factor for developing CRC, whilst the impact of family history on prognosis is unclear. The present study assessed the association between family history and prognosis and, based on current evidence, explored whether this association was modified by age at diagnosis. METHODS: Using data from the Swedish Colorectal Cancer Registry (SCRCR) linked with the Multigeneration Register and the National Cancer Register, we identified 31 801 patients with a CRC diagnosed between 2007 and 2016. The SCRCR is a clinically rich database which includes information on the cancer stage, grade, location, treatment, complications and postoperative follow-up. RESULTS: We estimated excess mortality rate ratios (EMRR) for relative survival and hazard ratios (HR) for disease-free survival with 95% confidence intervals (CIs) using flexible parametric models. We found no association between family history and relative survival (EMRR = 0.96, 95% CIs: 0.89-1.03, P = 0.21) or disease-free survival (HR = 0.98, 95% CIs: 0.91-1.06, P = 0.64). However, age was found to modify the impact of family history on prognosis. Young patients (<50 at diagnosis) with a positive family history had less advanced (i.e. stages I and II) cancers than those with no family history (OR = 0.71, 95% CI: 0.56-0.89, P = 0.004) and lower excess mortality even after adjusting for cancer stage (EMMR = 0.63, 95% CIs: 0.47-0.84, P = 0.002). CONCLUSIONS: Our results suggest that young individuals with a family history of CRC may have greater health awareness, attend opportunistic screening and adopt lifestyle changes, leading to earlier diagnosis and better prognosis.

Population-based analysis of outcomes with early-age colorectal cancer.

BACKGROUND: The aim was to evaluate differences in stage, treatment and prognosis in patients aged less than 50 years with colorectal cancer compared with older age groups. METHODS: This population-based study included all patients diagnosed with colorectal cancer in Sweden, 2010-2015. Disease stage, treatment, 5-year disease-free survival (DFS) and relative survival were analysed in relation to age groups: less than 50, 50-74 and at least 75 years. RESULTS: Of 34 434 patients included, 24·1, 19·7 and 14·0 per cent of patients aged less than 50, 50-74 and at least 75 years respectively were diagnosed with stage IV disease (P < 0·001). Adverse histopathological features were more common in young patients. Among patients aged less than 50 years, adjuvant chemotherapy was given to 18·9, 42·0 and 93·9 per cent of those with stage I, III and III disease respectively, compared with 0·7, 4·4 and 29·6 per cent of those aged 75 years or older (P < 0·001). Stage-adjusted DFS at 5 years for patients under 50 years old was 0·96, 0·90 and 0·77 in stage I, II and III respectively. Corresponding proportions were 0·88, 0·82 and 0·68 among patients aged 50-74 years, and 0·69, 0·62 and 0·49 for those aged 75 years or older. Relative survival was better for young patients only among those with stage III disease. CONCLUSION: Patients younger than 50 years with colorectal cancer had a poorer stage at diagnosis and received more intensive oncological treatment. DFS was better than that among older patients in early-stage disease.

ANTECEDENTES: El objetivo del estudio fue evaluar las diferencias en estadio, tratamiento y pronóstico en pacientes con cáncer colorrectal (colorectal cancer, CRC) de edad inferior a 50 años en comparación con los grupos de mayor edad. MÉTODOS: Estudio de base poblacional de todos los pacientes con CRC en Suecia 2010-2015. Se analizaron el estadio, tratamiento, supervivencia libre de enfermedad (disease-free survival, DFS) a los 5 años y supervivencia relativa (relative survival, RS) en los grupos de edad de < 50, 50-74, ≥ 75 años. RESULTADOS: De 34.434 pacientes incluidos, tenían un estadio IV en el momento del diagnóstico en el 24,1%, 19,7% y 14,0% de los pacientes de < 50, 50-74 y ≥ 75 años de edad, respectivamente (P < 0,001). Las características histopatológicas desfavorables fueron más frecuentes en pacientes jóvenes. Se administró quimioterapia adyuvante al 18,9%, 42,0% y 93,9% de los pacientes con edad inferior a 50 años con estadios I, II y III de la enfermedad respectivamente, en comparación con el 0,7%, 4,4% y 29,6% de los pacientes ≥ 75 años con estadios I, II y III, respectivamente (P < 0,001). La DFS ajustada por estadio de la enfermedad en los pacientes de < 50 años fue 0,96, 0,94 y 0,77 para los estadios I, II y III, respectivamente. Las proporciones correspondientes de DFS en los pacientes de edad entre 50-74 años fueron 0,88, 0,82 y 0,68, respectivamente, y, para los pacientes de ≥ 75 de edad fueron 0,69, 0,62 y 0,49, respectivamente. La RS fue solo mejor en los pacientes jóvenes con estadio III de la enfermedad. CONCLUSIÓN: Los pacientes menores de 50 años con CRC tenían un estadio peor de la enfermedad en el momento del diagnóstico y recibieron un tratamiento oncológico más intenso. La DFS fue mejor en comparación con pacientes mayores con estadio más temprano de la enfermedad.

Improvement of the experience of colorectal cancer patients in Sweden with a regional cancer plan.

AIM: The Stockholm-Gotland Regional Cancer Plan was launched in 2012 to improve cancer care. A personal contact nurse (CN), an individual written care plan (IWCP) and a standardized care pathway (SCP) were introduced. The aim of the current study was to evaluate whether these efforts have resulted in an improved experience for patients treated for colorectal cancer. METHOD: Patients treated with bowel resection for colorectal cancer in the Stockholm-Gotland region between 1 January 2013 and 31 December 2017 were identified through the Swedish Colorectal Cancer Registry. Six to eight months postoperatively, the patients received a patient-reported experience questionnaire. Patients were classified as 'satisfied' or 'not satisfied'. RESULTS: The questionnaire was sent to 4465 patients, and 3154 (70.64%) responded. The proportion of patients assigned a CN increased over time (79.84%-88.44%) and so did the proportion of patients receiving an IWCP (39.36%-70.00%). The waiting times were significantly shortened during the study period. In multivariable analysis, access to a CN and an IWCP was independently associated with increased patient satisfaction (OR 3.03, 95% CI 2.28-4.02 and OR 1.64, 95% CI 1.38-1.94). Patients with a long waiting time were significantly less satisfied than patients with a short waiting time (OR 0.72, 95% CI 0.60-0.88). CONCLUSION: Implementation of a CN, IWCP and SCP has been successful, measured by a higher proportion of patients gaining access to these assets and shortened waiting times. This has led to an improved patient experience in patients treated for colorectal cancer in the Stockholm-Gotland region.

International evaluation of circumferential resection margins after rectal cancer resection: insights from the Swedish and Dutch audits.

AIM: This study aimed to determine predictive factors for the circumferential resection margin (CRM) within two northern European countries with supposed similarity in providing rectal cancer care. METHOD: Data for all patients undergoing rectal resection for clinical tumour node metastasis (TNM) stage I-III rectal cancer were extracted from the Swedish ColoRectal Cancer Registry and the Dutch ColoRectal Audit (2011-2015). Separate analyses were performed for cT1-3 and cT4 stage. Predictive factors for the CRM were determined using univariable and multivariable logistic regression analyses. RESULTS: A total of 6444 Swedish and 12 089 Dutch patients were analysed. Over time the number of hospitals treating rectal cancer decreased from 52 to 42 in Sweden, and 82 to 79 in the Netherlands. In the Swedish population, proportions of cT4 stage (17% vs 8%), multivisceral resection (14% vs 7%) and abdominoperineal excision (APR) (37% vs 31%) were higher. The overall proportion of patients with a positive CRM (CRM+) was 7.8% in Sweden and 5.4% in the Netherlands. In both populations with cT1-3 stage disease, common independent risk factors for CRM+ were cT3, APR and multivisceral resection. No common risk factors for CRM+ in cT4 stage disease were found. An independent impact of hospital volume on CRM+ could be demonstrated for the cT1-3 Dutch population. CONCLUSION: Within two northern European countries with implemented clinical auditing, rectal cancer care might potentially be improved by further optimizing the treatment of distal and locally advanced rectal cancer.

Population-based study of surgical treatment with and without tumour resection in patients with locally recurrent rectal cancer.

BACKGROUND: Population-based studies of treatment of locally recurrent rectal cancer (LRRC) are lacking. The aim was to investigate the surgical treatment of patients with LRRC at a national population-based level. METHODS: All patients undergoing abdominal resection for primary rectal cancer between 1995 and 2002 in Sweden with LRRC as a first event were included. Detailed information about treatment, complications and outcomes was collected from the medical records. The patients were analysed in three groups: patients who had resection of the LRRC, those treated without tumour resection and patients who received best supportive care only. RESULTS: In all, 426 patients were included in the study. Of these, 149 (35·0 per cent) underwent tumour resection, 193 (45·3 per cent) had treatment without tumour resection and 84 (19·7 per cent) received best supportive care. Abdominoperineal resection was the most frequent surgical procedure, performed in 65 patients (43·6 per cent of those who had tumour resection). Thirteen patients had total pelvic exenteration. In total, 63·8 per cent of those whose tumour was resected had potentially curative surgery. After tumour resection, 62 patients (41·6 per cent) had a complication within 30 days. Patients who received surgical treatment without tumour resection had a lower complication rate but a significantly higher 30-day mortality rate than those who underwent tumour resection (10 versus 1·3 per cent respectively; P = 0·002). Of all patients included in the study, 22·3 per cent had potentially curative treatment and the 3-year survival rate for these patients was 56 per cent. CONCLUSION: LRRC is a serious condition with overall poor outcome. Patients undergoing curative surgery have an acceptable survival rate but substantial morbidity. There is room for improvement in the management of patients with LRRC.

Postoperative complications in relation to overall treatment time in patients with rectal cancer receiving neoadjuvant radiotherapy.

BACKGROUND: The optimal timing of surgery for rectal cancer after radiotherapy (RT) is disputed. The Stockholm III trial concluded that it was oncologically safe to delay surgery for 4-8 weeks after short-course RT (SRT), with fewer postoperative complications compared with SRT with surgery within a week. Other studies have indicated that an even shorter interval between RT and surgery (0-3 days) might be beneficial. The aim of this study was to identify the optimal interval to surgery after RT. METHODS: Patients were analysed as treated, in terms of overall treatment time (OTT), the interval from the start of RT until the day of surgery. Patients receiving SRT (5 × 5 Gy) were categorized according to OTT: 7 days (group A), 8-13 days (group B), 5-7 weeks (group C) and 8-13 weeks (group D). Patients receiving long-course RT (25 × 2 Gy) were grouped into those with an OTT of 9-11 weeks (group E) or 12-14 weeks (group F). Outcomes assessed were postoperative complications and early mortality. RESULTS: A total of 810 patients were analysed (group A, 100; group B, 247; group C, 192; group D, 160; group E, 52; group F, 59). Baseline patient characteristics were similar. There were significantly more overall complications in group B than in groups C and D. Adjusted odds ratios, with B as the reference group, were: 0·72 (95 per cent c.i. 0·40 to 1·32; P = 0·289), 0·50 (0·30 to 0·84; P = 0·009) and 0·39 (0·23 to 0·65; P < 0·001) for groups A, C and D respectively. Early mortality was similar in all groups. There were no significant differences between long-course RT groups. CONCLUSION: These results suggest that surgery should optimally be delayed for 4-12 weeks (OTT 5-13 weeks) after SRT.

Consensus and controversies regarding follow-up after treatment with curative intent of nonmetastatic colorectal cancer: a synopsis of guidelines used in countries represented in the European Society of Coloproctology.

AIM: It is common clinical practice to follow patients for a period of years after treatment with curative intent of nonmetastatic colorectal cancer, but follow-up strategies vary widely. The aim of this systematic review was to provide an overview of recommendations on this topic in guidelines from member countries of the European Society of Coloproctology, with supporting evidence. METHOD: A systematic search of Medline, Embase and the guideline databases Trip database, BMJ Best Practice and Guidelines International Network was performed. Quality assessment included use of the AGREE-II tool. All topics with recommendations from included guidelines were identified and categorized. For each subtopic, a conclusion was made followed by the degree of consensus and the highest level of evidence. RESULTS: Twenty-one guidelines were included. The majority recommended that structured follow-up should be offered, except for patients in whom treatment of recurrence would be inappropriate. It was generally agreed that clinical visits, measurement of carcinoembryoinc antigen and liver imaging should be part of follow-up, based on a high level of evidence, although the frequency is controversial. There was also consensus on imaging of the chest and pelvis in rectal cancer, as well as endoscopy, based on lower levels of evidence and with a level of intensity that was contradictory. CONCLUSION: In available guidelines, multimodal follow-up after treatment with curative intent of colorectal cancer is widely recommended, but the exact content and intensity are highly controversial. International agreement on the optimal follow-up schedule is unlikely to be achieved on current evidence, and further research should refocus on individualized 'patient-driven' follow-up and new biomarkers.

Prediction of outcome after curative surgery for colorectal cancer: preoperative haemoglobin, C-reactive protein and albumin.

AIM: The aim was to evaluate a scoring system using the values of preoperative haemoglobin, C-reactive protein (CRP) and albumin to predict colorectal cancer recurrence and survival. METHOD: Data on all curative resections for Stages I-III colorectal cancer performed at a tertiary referral hospital in 2007-2010 were recorded in the Swedish Colorectal Cancer Registry and were matched to local databases for laboratory results and blood transfusion. Patients who died within 30 days or during primary hospital admission were excluded. Preoperative haemoglobin, CRP and albumin levels were recorded for 417 patients. A score (0-3) was derived on the presence of anaemia (Hb < 120 g/l for women and < 130 g/l for men), raised CRP (> 10 mg/ml) and low albumin (< 35 g/dl). The risks for recurrence and impaired overall survival were assessed using Cox regression analyses. RESULTS: Impaired overall survival was found when one, two or three of the criteria anaemia, elevated CRP and low albumin were present prior to surgery [hazard ratio (HR) 3.61, 95% CI 1.66-7.85; HR 3.91, 95% CI 1.75-8.74; HR 4.85, 95% CI 2.15-10.93, respectively]. The risk for recurrence, however, was not related to the presence of these criteria. CONCLUSION: Overall survival after curative surgery for Stages I-III colorectal cancer is impaired when anaemia, elevated CRP or low albumin exist prior to surgery.

Pelvic local recurrence from colorectal cancer: surgical challenge with changing preconditions.

AIM: Although the rate of local recurrence (LR) after colorectal cancer surgery has decreased, it still poses major surgical and oncological challenges. The aims of this study, based on an audit from a tertiary referral centre, was to evaluate determinants associated with outcomes after surgery for pelvic LR and how these have changed over time. METHOD: Retrospective analysis of all resections for pelvic LR of colorectal cancer performed at the Karolinska University Hospital from January 2003 until August 2009 (period 1) and from September 2009 until November 2013 (period 2) . RESULTS: Ninety-five patients with pelvic LR were operated on with a curative intent. An R0 resection was achieved in 77% and an R1 resection in 23%. Lateral compartments were invaded in 48% and this proportion increased in resections performed in period 2 (37% vs 60%, P = 0.05). R1 resections were associated with a higher risk of local re-recurrence than R0 resections (64% vs 16%; OR = 8.90, 95% CI: 2.71-29.78). Lateral recurrences were associated with a lower R0-resection rate than nonlateral recurrences (63% vs 90%; OR = 0.20, 95% CI: 0.05-0.64) and a higher risk of treatment failure in terms of local re-recurrence or distant metastases, or death, as first event (hazard ratio [HR] = 1.75, 95% CI: 1.06-2.75). However, in a multivariate analysis only R1 resections remained a significant prognostic factor for treatment failure (HR = 2.37, 95% CI: 1.32-4.27). CONCLUSION: The proportion of lateral pelvic recurrences has increased over time. In comparison with non-lateral LRs, lateral LRs are more difficult to resect radically and are associated with worse overall and disease-free survival. However, with radical surgery many patients with pelvic locally recurrent colorectal cancer may be offered curative treatment.

Session 1: The surgeon as a prognostic factor in colon and rectal cancer?

The impact of quality of surgery, colorectal surgical specialization, training and expertise has been far greater on survival outcomes than adjuvant and neoadjuvant therapies. The review of the evidence by Professor Martling and expert discussion addresses the evidence base and the crucial importance of the surgeon as a prognostic factor, and how this has been relatively neglected in comparison to other resources invested in improving the treatment of colorectal cancer.

Complete mesocolic excision in right-sided colon cancer does not increase severe short-term postoperative adverse events.

AIM: The aim was to assess whether complete mesocolic excision (CME) in patients with right-sided colon cancer is related to short-term mortality or postoperative adverse events requiring reoperation. The complete mobilization of an integral mesocolon and central ligation of blood vessels are essential steps in CME surgery. The resultant specimen, with an intact mesocolic fascia and a high number of harvested lymph nodes, is believed to be oncologically favourable. However, it has been suggested that CME surgery may increase the risk of intra-operative severe adverse events, due to exposure of vital retroperitoneal organs and large blood vessels. METHOD: In a population-based, nested case-control study, all residents in the Stockholm County operated for right-sided colon cancer from 2004 until 2012 were identified from the Swedish Colorectal Cancer Registry. Patients who died within 90 days after surgery or were reoperated within 30 days after surgery, or during the index hospital stay, were defined as cases. Two controls per case were randomly sampled and individually matched for age, sex, TNM stage and emergency vs elective surgery. Exposure status (CME surgery) was assessed from original surgical reports. RESULTS: The estimated proportion of CME surgery was 14.8% (35 of 236) for cases and 19.5% (92 of 473) for controls. The unadjusted OR for short-term mortality or reoperation after CME surgery was 0.72 (95% CI: 0.47-1.10; P = 0.15). The ORs were lower in the late part of the study (0.51; 95% CI: 0.26-1.01) and in high volume hospitals (0.61, 95% CI: 0.35-1.06). CONCLUSIONS: The present study does not indicate that CME surgery is associated with an increased risk of severe adverse events such as 90-day mortality or reoperation.

Population-based study of factors predicting treatment intention in patients with locally recurrent rectal cancer.

BACKGROUND: Local recurrence of rectal cancer (LRRC) is associated with poor survival unless curative treatment is performed. The aim of this study was to investigate predictive factors for treatment with curative intent in patients with LRRC. METHODS: Population-based data for patients treated for primary rectal cancer between 1995 and 2002, and with LRRC reported as first event were collected from the Swedish Colorectal Cancer Registry and medical records. The associations between patient-, primary tumour- and LRRC-related factors and intention of the treatment for LRRC were determined. The impact of the identified predictive factors on prognosis after treatment with curative intent was also assessed. RESULTS: A total of 426 patients were included in the study, of whom 149 (35·0 per cent) received treatment with curative intent. Factors significantly associated with treatment of the LRRC with palliative intent were primary surgery with abdominoperineal resection (odds ratio (OR) 5·16, 95 per cent c.i. 2·97 to 8·97), age at diagnosis of LRRC at least 80 years (OR 4·82, 2·37 to 9·80), symptoms at diagnosis (OR 2·79, 1·56 to 5·01) and non-central location of the LRRC (OR 1·79, 1·15 to 2·79). The overall 5-year survival rate was 8·9 per cent for all patients and 23·1 per cent among those treated with curative intent. In patients treated with curative intent, factors associated with increased risk of death were age 80 years or more (hazard ratio (HR) 2·44, 95 per cent c.i. 1·55 to 3·86), presence of symptoms (HR 1·92, 1·20 to 3·05), non-central tumour location (HR 1·51, 1·01 to 2·26) and presence of hydronephrosis (HR 2·02, 1·18 to 3·44). CONCLUSION: Non-central location of the LRRC, presence of symptoms and age at least 80 years at diagnosis of the LRRC were associated with treatment with palliative intent.

Risk of second primary cancer in patients treated with radiotherapy for rectal cancer.

BACKGROUND: Many patients with rectal cancer receive radiotherapy (RT) to reduce the risk of local recurrence. Radiation may give rise to adverse effects, including second primary cancers. In view of the divergent results of previous studies, the present study evaluated the risk of second primary cancer following RT in all randomized RT rectal cancer trials conducted in Sweden and in the Swedish ColoRectal Cancer Registry (SCRCR). METHODS: Patients included in five randomized trials and the SCRCR were linked to the Swedish Cancer Registry. Cox regression models estimated the hazard ratio (HR) of second primary cancer among patients who received RT compared with those who did not. RESULTS: A total of 13 457 patients were included in this study; 7024 (52·2 per cent) received RT and 6433 (47·8 per cent) had surgery alone. Overall, no increased risk of second primary cancer was observed with RT (HR 1·03; 95 per cent c.i. 0·92 to 1·15), independently of follow-up time and location within or outside of the irradiated volume. In the randomized trials, with longer follow-up (maximum 31 years), a slight increase was observed outside of (HR 1·33, 1·01 to 1·74) but not within (HR 1·11, 0·73 to 1·67) the irradiated volume. Irradiated men had a lower risk of prostate cancer than those treated with surgery alone (HR 0·68, 0·51 to 0·91). CONCLUSION: Overall, there was no increased risk of second primary cancer following RT for rectal cancer within or outside of the irradiated volume up to 20 years of follow-up. Men with rectal cancer who received RT had a reduced risk of prostate cancer.

Accuracy of preoperative T and N staging in colon cancer--a national population-based study.

AIM: To select patients for neoadjuvant therapy in colon cancer, there is a need to improve pre-therapeutic locoregional staging. There are now data showing that the TN stage can be adequately assessed by preoperative CT in dedicated centres. In Sweden the use of preoperative CT of the abdomen for staging of the primary tumour is increasing. The aim of this study was to determine to what extent the preoperatively reported radiological TN stage correlates with the histopathological TN stage in an entire population. METHOD: Data were collected on the preoperative cTN stage according to the radiologist and postoperative pTN stage according to the pathologist on all patients operated on for colon cancer in Sweden 2007-2010. The correlation between cTN stage and pTN stage was calculated using kappa statistics. RESULTS: T stage was compared in 4373 patients with cT and pT stage. The correlation coefficient was 0.44, indicating fair agreement. The cN and pN correlation coefficient was 0.28, indicating a slight correlation. There was no difference in correlation related to age, gender, tumour location, body mass index or emergent vs elective surgery. A slight difference was seen between different geographical regions. CONCLUSION: Preoperative CT in an unselected population does not result in an accurate cTN staging as previously reported from dedicated centres. To achieve adequate preoperative cTN staging nationally, the education of radiologists and optimization of the radiological method will be necessary.

External validation of models predicting the individual risk of metachronous peritoneal carcinomatosis from colon and rectal cancer.

AIM: To externally validate previously published predictive models of the risk of developing metachronous peritoneal carcinomatosis (PC) after resection of nonmetastatic colon or rectal cancer and to update the predictive model for colon cancer by adding new prognostic predictors. METHOD: Data from all patients with Stage I-III colorectal cancer identified from a population-based database in Stockholm between 2008 and 2010 were used. We assessed the concordance between the predicted and observed probabilities of PC and utilized proportional-hazard regression to update the predictive model for colon cancer. RESULTS: When applied to the new validation dataset (n = 2011), the colon and rectal cancer risk-score models predicted metachronous PC with a concordance index of 79% and 67%, respectively. After adding the subclasses of pT3 and pT4 stage and mucinous tumour to the colon cancer model, the concordance index increased to 82%. CONCLUSION: In validation of external and recent cohorts, the predictive accuracy was strong in colon cancer and moderate in rectal cancer patients. The model can be used to identify high-risk patients for planned second-look laparoscopy/laparotomy for possible subsequent cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

Risk of disability pension in patients following rectal cancer treatment and surgery.

BACKGROUND: Aspects of survivorship, such as long-term ability to work, are increasingly relevant owing to the improved survival of patients with rectal cancer. The aim of this study was to assess risk and determinants of disability pension (DP) in this patient group. METHODS: Using Swedish national clinical and population-based registers, patients with stage I-III rectal cancer aged 18-61 years in 1995-2009 were identified at diagnosis and matched with population comparators. Prospectively registered records of DP during follow-up were retrieved up to 2013. Non-proportional and proportional hazards models were used to estimate the incidence rate ratio (IRR) for DP annually and overall. Potential variations in risk by demographic and clinical factors were calculated, with relapse as a time-varying exposure. RESULTS: A total of 2815 patients were identified and compared with 13 465 population comparators. During a median follow-up of 6·0 (range 0-10) years, 23·3 per cent of the relapse-free patients and 10·3 per cent of the population comparators received DP (IRR 2·40, 95 per cent c.i. 2·17 to 2·65). An increased annual risk of DP was evident almost every year until the tenth year of follow-up. Abdominoperineal resection was associated with an increased DP risk compared with anterior resection (IRR 1·44, 1·19 to 1·75). Surgical complications (IRR 1·33, 1·10 to 1·62) and reoperation (IRR 1·42, 1·09 to 1·84), but not radiotherapy or chemotherapy, were associated with risk of DP. CONCLUSION: Relapse-free patients with rectal cancer of working age are at risk of disability pension.

Tumour regression in the randomized Stockholm III Trial of radiotherapy regimens for rectal cancer.

BACKGROUND: The Stockholm III Trial randomized patients with primary operable rectal cancers to either short-course radiotherapy (RT) with immediate surgery (SRT), short-course RT with surgery delayed 4-8 weeks (SRT-delay) or long-course RT with surgery delayed 4-8 weeks. This preplanned interim analysis examined the pathological outcome of delaying surgery. METHODS: Patients randomized to the SRT and SRT-delay arms in the Stockholm III Trial between October 1998 and November 2010 were included, and data were collected in a prospective register. Additional data regarding tumour regression grade, according to Dworak, and circumferential margin were obtained by reassessment of histopathological slides. RESULTS: A total of 462 of 545 randomized patients had specimens available for reassessment. Patients randomized to SRT-delay had earlier ypT categories, and a higher rate of pathological complete responses (11·8 versus 1·7 per cent; P = 0·001) and Dworak grade 4 tumour regression (10·1 versus 1·7 per cent; P < 0·001) than patients randomized to SRT without delay. Positive circumferential resection margins were uncommon (6·3 per cent) and rates did not differ between the two treatment arms. CONCLUSION: Short-course RT induces tumour downstaging if surgery is performed after an interval of 4-8 weeks.