Risk Factors Associated With Circumferential Resection Margin Positivity in Rectal Cancer: A Binational Registry Study

Development of a joint prediction model based on both the radiomics and clinical factors for preoperative prediction of circumferential resection margin in middle-low rectal cancer using T2WI images

OBJECTIVES

A circumferential resection margin (CRM) is an independent risk factor for local recurrence, distant metastasis, and poor overall survival of rectal cancer. In this study, we developed and validated a radiomics prediction model to predict perioperative surgical margins in patients with middle and low rectal cancer following neoadjuvant treatment and for decisions about treatment plans for patients.

METHODS

This study retrospectively analyzed 275 patients from center 1(training cohort) and 120 patients from center 2(verification cohort) with rectal cancer diagnosed at two centers from July 2020 to July 2022 who underwent neoadjuvant therapy and had their CRM status confirmed by preoperative high-resolution magnetic resonance imaging (MRI) scans. Radiomics signatures were extracted and screened from MRI images and a radiomics signature was built by the least absolute shrinkage and selection operator (LASSO) logistic regression model, which was combined with clinical signatures to construct a nomogram. The receiver operating characteristic (ROC) curve and area under the curve (AUC) value, sensitivity, specificity, positive predictive value, negative predictive value, and calibration curve were used to evaluate the predictive performance of the model.

RESULTS

In our research, the combined model has the best performance. In the training group, the radiomics model based on high-spatial-resolution T2-weighted imaging (HR-T2WI), clinical model and combined model demonstrated an AUC of 0.819 (0.802-0.833), 0.843 (0.822-0.861), and 0.910 (0.880-0.940), respectively. In the validation group, they demonstrated an AUC of 0.745 (0.715-0.788), 0.827 (0.798-0.850), and 0.848 (0.779-0.917), respectively. The calibration curve confirmed the clinical applicability of the model.

CONCLUSIONS

The individualized prediction model established by combining radiomics signatures and clinical signatures can efficiently and objectively predict perioperative margin invasion in patients with middle and low rectal cancer.

Is survival after transanal total mesorectal excision (taTME) worse than that after traditional total mesorectal excision? A retrospective propensity score-adjusted cohort study

PURPOSE

Transanal total mesorectal excision (taTME) was developed to provide better vision during resection of the mesorectum. Conflicting results have shown an increase in local recurrence and shorter survival after taTME. This study compared the outcomes of taTME and abdominal (open, laparoscopic, robotic) total mesorectal excision (abTME).

METHODS

Patients who underwent taTME or abTME for stages I-III rectal cancer and who received an anastomosis were included. A retrospective analysis of a prospectively conducted database was performed. The primary endpoints were overall survival (OS), cancer-specific survival (CSS), and disease-free survival (DFS). Risk factors were adjusted by propensity score matching (PSM). The secondary endpoints were local recurrence rates and combined poor pathological outcomes.

RESULTS

From 2012 to 2020, a total of 189 patients underwent taTME, and 119 underwent abTME; patients were followed up for a mean of 54.7 (SD 24.2) and 78.4 (SD 34.8) months, respectively (p < 0.001). The 5-year survival rates after taTME and abTME were not significantly different after PSM: OS: 78.2% vs. 88.6% (p = 0.073), CSS: 87.4% vs. 92.1% (p = 0.359), and DFS: 69.3% vs. 80.9% (p = 0.104), respectively. No difference in the local recurrence rate was observed (taTME, n = 10 (5.3%); abTME, n = 10 (8.4%); p = 0.280). Combined poor pathological outcomes were more frequent after abTME (n = 36, 34.3%) than after taTME (n = 35, 19.6%) (p = 0.006); this difference was nonsignificant according to multivariate analysis (p = 0.404).

CONCLUSION

taTME seems to be a good treatment option for patients with rectal cancer and is unlikely to significantly affect local recurrence or survival. However, further investigations concerning the latter are warranted.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT0496910).

Short-term results in a population based study indicate advantage for minimally invasive rectal cancer surgery versus open

BACKGROUND

The aim of this study was to determine if minimally invasive surgery (MIS) for rectal cancer is non-inferior to open surgery (OPEN) regarding adequacy of cancer resection in a population based setting.

METHODS

All 9,464 patients diagnosed with rectal cancer 2012-2018 who underwent curative surgery were included from the Swedish Colorectal Cancer Registry.

PRIMARY OUTCOMES

Positive circumferential resection margin (CRM < 1 mm) and positive resection margin (R1). Non-inferiority margins used were 2.4% and 4%.

SECONDARY OUTCOMES

30- and 90-day mortality, clinical anastomotic leak, re-operation < 30 days, 30- and 90-day re-admission, length of stay (LOS), distal resection margin < 1 mm and < 12 resected lymph nodes. Analyses were performed by intention-to-treat using unweighted and weighted multiple regression analyses.

RESULTS

The CRM was positive in 3.8% of the MIS group and 5.4% of the OPEN group, risk difference -1.6% (95% CI -1.623, -1.622). R1 was recorded in 2.8% of patients in the MIS group and in 4.4% of patients in the OPEN group, risk difference -1.6% (95% CI -1.649, -1.633). There were no differences between the groups in adjusted unweighted and weighted analyses. All analyses demonstrated decreased mortality and re-admissions at 30 and 90 days as well as shorter LOS following MIS.

CONCLUSIONS

In this population based setting MIS for rectal cancer was non-inferior to OPEN regarding adequacy of cancer resection with favorable short-term outcomes.

Real-time classification of tumour and non-tumour tissue in colorectal cancer using diffuse reflectance spectroscopy and neural networks to aid margin assessment

BACKGROUND

Colorectal cancer is the third most commonly diagnosed malignancy and the second leading cause of mortality worldwide. A positive resection margin following surgery for colorectal cancer is linked with higher rates of local recurrence and poorer survival. We investigated diffuse reflectance spectroscopy (DRS) to distinguish tumour and non-tumour tissue in ex vivo colorectal specimens, to aid margin assessment and provide augmented visual maps to the surgeon in real-time.

METHODS

Patients undergoing elective colorectal cancer resection surgery at a London-based hospital were prospectively recruited. A hand-held DRS probe was used on the surface of freshly resected ex vivo colorectal tissue. Spectral data was acquired for tumour and non-tumour tissue. Binary classification was achieved using conventional machine learning classifiers and a convolutional neural network (CNN), which were evaluated in terms of sensitivity, specificity, accuracy and the area under the curve.

RESULTS

A total of 7692 mean spectra were obtained for tumour and non-tumour colorectal tissue. The CNN-based classifier was the best performing machine learning algorithm, when compared to contrastive approaches, for differentiating tumour and non-tumour colorectal tissue, with an overall diagnostic accuracy of 90.8% and area under the curve of 96.8%. Live on-screen classification of tissue type was achieved using a graduated colourmap.

CONCLUSION

A high diagnostic accuracy for a DRS probe and tracking system to differentiate ex vivo tumour and non-tumour colorectal tissue in real-time with on-screen visual feedback was highlighted by this study. Further in vivo studies are needed to ensure integration into a surgical workflow.

Predicting Positive Radial Margin on Restaging MRI of Patients with Low Rectal Cancer: Can We Do Better?

Objective  The aim of this study was to characterize the tissue involving the margin and study if this information will affect margin prediction on restaging magnetic resonance imaging (MRI) in low rectal adenocarcinoma (LRC) patients treated with neoadjuvant long-course chemoradiotherapy (LCCRT). Methods  In this retrospective study of nonmetastatic LRC (distal margin <5 cm from the anal verge) treated with LCCRT followed by surgery, a radiologist blinded to outcome reread the restaging MRI and documented if the radial margin was involved by tumor, fibrosis, or mucin reaction using T2 high-resolution (HR) and diffusion-weighted imaging (DWI). The diagnostic performance of tumor-involving margin on restaging MRI was assessed using surgical histopathology as a reference. Interobserver agreement between three independent radiologists was assessed in a subset. Results  We included 133 patients (80 males and 53 females) with a mean (range) age of 44.7 (21-86) years and 82% of them had well or moderately differentiated adenocarcinoma. Baseline MRI showed T3 ( n  = 58) or T4 ( n  = 60) disease in 89% of the patients. The pathological margin was positive in 21% ( n  = 28) cases. In restaging MRI, the circumferential resection margin (CRM) ≤1 mm in 75.1% ( n  = 100) cases and MRI predicted tumor, fibrosis, and mucin reaction at the margin in 60, 34, and 6%, respectively, and histopathology showed tumor cells in 33, 14.7, and 16.6% of them, respectively. LRC with tumor-involving margin and bad response (MR tumor regression grade [mr-TRG] 3-5) on restaging MRI had fourfold increased risk of positive pathological circumferential resection margin (pCRM). There was moderate and fair inter-reader agreement for the tissue type involving the CRM ( κ  = 0.471) and mr-TRG ( κ  = 0.266), p  < 0.05. The use of both distance criteria and tumor-involving margins improved the diagnostic accuracy for margin prediction from 39 to 66% on restaging MRI. Conclusions  Margin prediction on restaging MRI can be improved by characterizing the tissue type involving the margin in low rectal cancer patients. The inter-reader agreement was moderate for determining the tissue type.

Tumour, narrow pelvis and surgery specific factors for total mesorectal excision quality and morbidity following rectal cancer resection

BACKGROUND

Pelvic anatomy is critical in challenging rectal resections. This study investigated how pelvic anatomy relates to total mesorectal excision (TME) quality, anastomotic leakage rate, and long-term oncological outcomes.

METHODS

Patients undergoing elective rectal cancer resection from 2008 to 2017 in an Austrian institution were retrospectively reviewed regardless of the surgical approach. CT scans were analysed for pelvic measurements and volumes. The primary outcomes of interest were the correlation between pelvic dimensions and the TME quality and anastomotic leakage. Subanalysis was done by surgical approach (open, laparoscopic, transanal TME). Secondary outcomes were overall and disease-free survivals.

RESULTS

Among 154 eligible patients, 112 were included. The angle between pubic symphysis and promontory significantly correlated with worse TME grades (TME grade 1: mean(s.d.) 102.7(5.7)°; TME grade 2: 92.0(4.4)°; TME grade 3: 91.4(3.6)°; P < 0.001). A significantly lower distance between tumour and circumferential resection margin (CRM) was observed in grade 3 resections, whereas no difference appeared in grade 1 and grade 2 resection (TME grade 1: mean(s.d.) 11.92(9.4) mm; TME grade 2: 10.8(8.1) mm; TME grade 3: 3.1(4.1) mm; P = 0.003). The anastomotic leakage rate was significantly higher in case of a lower CRM (patients with anastomotic leakage: mean(s.d.) 6.8(5.8) mm versus others: 12.6(9.8) mm, P = 0.027), but not associated with pelvimetry measurements. The transanal TME (TaTME) subgroup displayed a wider angle between the pubic symphysis and promontory, younger age and improved TME quality compared to others (respectively, mean TME grades in TaTME versus open versus laparoscopic: 1.0 ± 0.0, 1.5 ± 0.7 and 1.3 ± 0.5, P = 0.013). Finally, oncological survival was not impacted by pelvic measurements or worse TME quality.

CONCLUSION

The angle between the pubic symphysis and promontory and the distance between tumour and CRM were associated with worse TME grades. The anastomotic leakage was associated with a lower CRM but not with pelvimetric measures.

Prognostic Value of the Circumferential Resection Margin After Curative Surgery for Rectal Cancer: A Multicenter Propensity Score-Matched Analysis

BACKGROUND

Recently, positive circumferential resection margin has been found to be an indicator of advanced disease with a high risk of distant recurrence rather than local recurrence.

OBJECTIVE

The study aimed to analyze the prognostic impact of the circumferential resection margin on long-term oncological outcomes in patients with rectal cancer.

DESIGN

This was a multicenter, propensity score-matched (2:1) analysis comparing the positive and negative circumferential resection margins.

SETTINGS

The study was conducted at 5 high-volume centers in Spain.

PATIENTS

Patients who underwent total mesorectal excision with curative intent for middle-low rectal cancer between 2006 and 2014 were included.

MAIN OUTCOME MEASURES

The main outcomes were local recurrence, distant recurrence, overall survival, and disease-free survival.

RESULTS

The unmatched initial cohort consisted of 1599 patients, of whom 4.9% had a positive circumferential resection margin. After matching, 234 patients were included (156 with a negative circumferential margin and 78 with a positive circumferential margin). The median follow-up period was 52.5 (22.0-69.5) months. Local recurrence was significantly higher in patients with a positive circumferential margin (33.3% vs 11.5%; p < 0.001). Distant recurrence was similar in both groups (46.2% vs 42.3%; p = 0.651). There were no statistically significant differences in 5-year overall survival (48.6% vs 43.6%; p = 0.14). Disease-free survival was lower in patients with a positive circumferential margin (36.1% vs 52.3%; p = 0.026).

LIMITATIONS

This study was limited by its retrospective design. The different neoadjuvant treatment options were not included in the propensity score.

CONCLUSIONS

The positive circumferential resection margin was associated with a higher local recurrence rate and worse disease-free survival in comparison with the negative circumferential resection margin. However, the positive circumferential resection margin was not a prognostic indicator of distant recurrence and overall survival. See Video Abstract at http://links.lww.com/DCR/B950 .

VALOR PRONSTICO DEL MARGEN DE RESECCIN CIRCUNFERENCIAL DESPUS DE LA CIRUGA CURATIVA PARA EL CNCER DE RECTO UN ANLISIS MULTICNTRICO EMPAREJADO POR PUNTAJE DE PROPENSIN

ANTECEDENTES:En los últimos años, se ha encontrado que el margen de resección circunferencial positivo es un indicador de enfermedad avanzada con alto riesgo de recurrencia a distancia más que de recurrencia local.OBJETIVO:El objetivo fue analizar el impacto pronóstico del margen de resección circunferencial sobre la recidiva local, a distancia y las tasas de supervivencia en pacientes con cáncer de recto.DISEÑO:Este fue un análisis multicéntrico emparejado por puntaje de propensión 2: 1 que comparó el margen de resección circunferencial positivo y negativo.AJUSTES:El estudio se realizó en 5 centros Españoles de alto volumen.PACIENTES:Se incluyeron pacientes sometidos a escisión total de mesorrecto con intención curativa por cáncer de recto medio-bajo entre 2006-2014. Las características clínicas e histológicas se utilizaron para el emparejamiento.PRINCIPALES MEDIDAS DE RESULTADO:Los resultadoes principales fueron la recurrencia local, la recurrencia a distancia, la supervivencia global y libre de enfermedad.RESULTADOS:La cohorte inicial no emparejada consistió en 1599 pacientes; El 4,9% tuvo un margen de resección circunferencial positivo. Tras el emparejamiento se incluyeron 234 pacientes (156 con margen circunferencial negativo y 78 con margen circunferencial positivo). La mediana del período de seguimiento fue de 52,5 meses (22,0-69,5). La recurrencia local fue significativamente mayor en pacientes con margen circunferencial positivo, 33,3% vs 11,5% [HR 3,2; IC 95%: 1,83-5,43; p < 0,001]. La recidiva a distancia fue similar en ambos grupos (46,2 % frente a 42,3 %) [HR 1,09, IC 95 %: 0,78-1,90; p = 0,651]. No hubo diferencias significativas en la supervivencia global a 5 años (48,6 % frente a 43,6 %) [HR 1,09, IC 95 %: 0,92-1,78; p = 0,14]; La supervivencia libre de enfermedad fue menor en pacientes con margen circunferencial positivo, 36,1% vs 52,3% [HR 1,5; IC 95%: 1,05-2,06; p = 0,026].LIMITACIONES:Este estudio estuvo limitado por el diseño retrospectivo. Las diferentes opciones de tratamientos neoadyuvantes no se han incluido en la puntuación de propensión.CONCLUSIONES:El margen de resección circunferencial positivo se asocia con una mayor tasa de recurrencia local y peor supervivencia libre de enfermedad en comparación con el margen de resección circunferencial negativo. Sin embargo, el margen de resección circunferencial positivo no fue un indicador pronóstico de recidiva a distancia ni de supervivencia global. Consulte el Video del Resumen en http://links.lww.com/DCR/B950 . (Traducción- Dr. Yesenia Rojas-Khalil ).

Outcomes of open vs laparoscopic vs robotic vs transanal total mesorectal excision (TME) for rectal cancer: a network meta-analysis

BACKGROUND

Total mesorectal excision (TME) for rectal cancer can be achieved using open (OpTME), laparoscopic (LapTME), robotic (RoTME), or transanal techniques (TaTME). However, the optimal approach for access remains controversial. The aim of this network meta-analysis was to assess operative and oncological outcomes of all four surgical techniques.

METHODS

Ovid MEDLINE, EMBASE, and PubMed databases were searched systematically from inception to September 2020, for randomised controlled trials (RCTs) comparing any two TME surgical techniques. A network meta-analysis using a Bayesian random-effects framework and mixed treatment comparison was performed. Primary outcomes were the rate of clear circumferential resection margin (CRM), defined as > 1 mm from the closest tumour to the cut edge of the tissue, and completeness of mesorectal excision. Secondary outcomes included radial and distal resection margin distance, postoperative complications, locoregional recurrence, disease-free survival, and overall survival. Surface under cumulative ranking (SUCRA) was used to rank the relative effectiveness of each intervention for each outcome. The higher the SUCRA value, the higher the likelihood that the intervention is in the top rank or one of the top ranks.

RESULTS

Thirty-two RCTs with a total of 6151 patients were included. Compared with OpTME, there was no difference in the rates of clear CRM: LapTME RR = 0.99 (95% (Credible interval) CrI 0.97-1.0); RoTME RR = 1.0 (95% CrI 0.96-1.1); TaTME RR = 1.0 (95% CrI 0.96-1.1). There was no difference in the rates of complete mesorectal excision: LapTME RR = 0.98 (95% CrI 0.98-1.1); RoTME RR = 1.1 (95% CrI 0.98-1.4); TaTME RR = 1.0 (95% CrI 0.91-1.2). RoTME was associated with improved distal resection margin distance compared to other techniques (SUCRA 99%). LapTME had a higher rate of conversion to open surgery when compared with RoTME: RoTME RR = 0.23 (95% CrI 0.034-0.70). Length of stay was shortest in RoTME compared to other surgical approaches: OpTME mean difference in days (MD) 3.3 (95% CrI 0.12-6.0); LapTME MD 1.7 (95% CrI - 1.1-4.4); TaTME MD 1.3 (95% CrI - 5.2-7.4). There were no differences in 5-year overall survival (LapTME HR 1.1, 95% CrI 0.74, 1.4; TaTME HR 1.7, 95% CrI 0.79, 3.4), disease-free survival rates (LapTME HR 1.1, 95% CrI 0.76, 1.4; TaTME HR 1.1, 95% CrI 0.52, 2.4), or anastomotic leakage (LapTME RR = 0.92 (95% CrI 0.63, 1.1); RoTME RR = 1.0 (95% CrI 0.48, 1.8); TaTME RR = 0.53 (95% CrI 0.19, 1.2). The overall quality of evidence as per Grading of Recommendations Assessment, Development and Evaluation (GRADE) assessments across all outcomes including primary and secondary outcomes was deemed low.

CONCLUSIONS

In selected patients eligible for a RCT, RoTME achieved improved distal resection margin distance and a shorter length of hospital stay. No other differences were observed in oncological or recovery parameters between (OpTME), laparoscopic (LapTME), robotic (RoTME), or trans-anal TME (TaTME). However, the overall quality of evidence across all outcomes was deemed low.

Patterns and predictors of recurrence after laparoscopic resection of rectal cancer

Purpose

This study was designed to evaluate the patterns and predictors of recurrence in patients who underwent laparoscopic resection of rectal cancer.

Methods

Patients with rectal cancer receiving laparoscopic resection between April 2009 and March 2016 were retrospectively analyzed. The association of recurrence with clinicopathological characteristics was evaluated using multivariate analyses.

Results

A total of 405 consecutive patients were included in our study. Within a median follow-up time of 62 months, 77 patients (19.0%) experienced disease recurrence: 10 (2.5%) had locoregional recurrence (LR), 61 (15.1%) had distant metastasis (DM), and 6 (1.5%) developed LR and DM synchronously. The lung was the most common site of metastasis. Multivariate analyses indicated that involved circumferential resection margin (CRM) was the only independent predictor for LR (OR=13.708, 95% CI 3.478-54.026, P&lt;0.001), whereas elevated baseline level of CA19-9 (OR=3.299, 95% CI 1.461-7.449, P=0.032), advanced pN stage (OR=2.292, 95% CI 1.177-4.462, P=0.015) and harvested lymph nodes less than 12 (OR=2.418, 95% CI 1.245-4.695, P=0.009) were independently associated with DM. Patients receiving salvage surgery showed superior 3-year survival compared with palliative treatment after relapse (90.9% vs. 20.5%; P=0.017). The estimated 5-year DFS and CSS for the entire cohort was 80.2% and 83.1%, respectively.

Conclusions

DM was more common than LR after laparoscopic resection of rectal cancer, and there were several clinicopathological factors related to LR and DM. Involved CRM and suboptimal lymph node yield were adverse surgery-related factors of tumor recurrence, which should be paid more attention to during the operation.

Clinical assessment for non-reversal stoma and stoma re-creation after reversal surgery for rectal cancer patients after sphincter-saving operation

BACKGROUND

This study aimed to identify the risk factors for permanent stoma (PS) in patients who underwent sphincter-saving operations for rectal cancer.

METHODS

We retrospectively reviewed 597 consecutive patients with rectal cancer from January 2012 to December 2020 at Taipei Medical University Hospital. Univariate and multivariable analyses were used to analyze risk factors for PS.

RESULTS

After a mean follow-up of 47.3 months (range 7-114 months), 59 patients (15.1%) were alive with a PS, including 46 patients who did not undergo reversal surgery and 13 patients who underwent stoma re-creation after reversal surgery. The mean period between primary surgery and stoma reversal was 6.0 months. Multivariate analysis revealed that the risk factors for PS were local recurrence [odd ratio (OR), 25.58; 95% confidence interval (CI), 4.428-147.761; p < 0.001], perirectal abscess [OR, 154.34; 95% CI, 15.806 - >999; p < 0.001], anastomosis site stenosis [OR, 187.081; 95% CI, 22.193 - >999; p < 0.001], perineural invasion [OR, 4.782; 95% CI, 1.22-18.736; p = 0.025], and operation time (min) [OR, 1.008; 95% CI, 1.002-1.014; p = 0.01].

CONCLUSIONS

Local recurrence, perirectal abscess, anastomosis site stenosis, perineural invasion, and operation time were independent risk factors for PS. Therefore, before a patient undergoes surgery for rectal cancer, surgeons should consider the possibility of the need for a PS, and patients should be informed before the operation that closure of the temporary stoma may not always be possible.

Regional variance in treatment and outcomes of locally invasive (T4) rectal cancer in Australia and New Zealand: analysis of the Bi-National Colorectal Cancer Audit

Backgrounds

Locally invasive T4 rectal cancer often requires neoadjuvant treatment followed by multi‐visceral surgery to achieve a radical resection (R0), and referral to a specialized exenteration quaternary centre is typically recommended. The aim of this study was to explore regional variance in treatment and outcomes of patients with locally advanced rectal cancer in Australia and New Zealand (ANZ).

Methods

Data were collected from the Bi‐National Colorectal Cancer Audit (BCCA) database. Rectal cancer patients treated between 2007 and 2019 were divided into six groups based on region (state/country) using patient postcode. A subset analysis of patients with T4 cancer was performed. Primary outcomes were positive circumferential resection margin (CRM+), and positive circumferential and/or distal resection margin (CRM/DRM+).

Results

A total of 9385 patients with rectal cancer were identified, with an overall CRM+ rate of 6.4% and CRM/DRM+ rate of 8.6%. There were 1350 patients with T4 rectal cancer (14.4%). For these patients, CRM+ rate was 18.5%, and CRM/DRM+ rate was 24.1%. Significant regional variation in CRM+ (range 13.4–26.0%; p = 0.025) and CRM/DRM+ rates (range 16.1–29.3%; p = 0.005) was identified. In addition, regions with higher CRM+ and CRM/DRM+ rates reported lower rates of multi‐visceral resections: range 24.3–26.8%, versus 32.6–37.3% for regions with lower CRM+ and CRM/DRM+ rates (p < 0.0001).

Conclusion

Positive resection margins and rates of multi‐visceral resection vary between the different regions of ANZ. A small subset of patients with T4 rectal cancer are particularly at risk, further supporting the concept of referral to specialized exenteration centres for potentially curative multi‐visceral resection.

Bayesian network structure for predicting local tumor recurrence in rectal cancer patients treated with neoadjuvant chemoradiation followed by surgery

Background and Purpose

Tumor recurrence, a characteristic of malignant tumors, is the biggest concern for rectal cancer survivors. The epidemiology of the disease calls for a pressing need to improve healthcare quality and patient outcomes. Prediction models such as Bayesian networks, which can probabilistically reason under uncertainty, could assist caregivers with patient management. However, some concerns are associated with the standard approaches to developing these structures in medicine. Therefore, this study aims to compare Bayesian network structures that stem from these two techniques.

Patients and Methods

A retrospective analysis was performed on 6754 locally advanced rectal cancer (LARC) patients enrolled in 14 international clinical trials. Local tumor recurrence at 2, 3, and 5-years was defined as the endpoints of interest. Five rectal cancer treating physicians from three countries elicited the expert structure. The algorithmic structure was inferred from the data with the hill-climbing algorithm. Structural performance was assessed with calibration plots and area under the curve values.

Results

The area under the curve for the expert structure on the training and validation data was above 0.9 and 0.8, respectively, for all the time points. However, the algorithmic structure had superior predictive performance over the expert structure for all time points of interest.

Conclusion

We have developed and internally validated a Bayesian networks structure from experts' opinions, which can predict the risk of a LARC patient developing a tumor recurrence at 2, 3, and 5 years. Our result shows that the algorithmic-based structures are more performant and less interpretable than expert-based structures.

Prognostic implications of surgical specimen quality on the oncological outcomes of open and laparoscopic surgery in mid and low rectal cancer

Purpose

Determine differences in pathologic outcomes between laparoscopic (LAP) and open surgery (OPEN) for mid and low rectal cancer and its influence in long-term oncological outcomes.

Methods

Retrospective case matched study at a tertiary institution. Adults with rectal cancer below 12 cm from the anal verge operated between January 2005 and September 2018 were included. Primary outcomes were quality of specimen, overall survival (OS), disease-free survival (DFS), and local recurrence (LR).

Results

The study included 311 patients, LAP = 108 (34.7%), OPEN = 203 (65,3%). A successful resection was accomplished in 81% of the LAP group and in 84.5% of the OPEN (p = 0.505). No differences in free distal margin (LAP = 100%, OPEN = 97.5%; p = 0.156) or circumferential resection margin (LAP = 95.2%, OPEN = 93.2%; p = 0.603) were observed. However, mesorectum quality was incomplete in 16.2% for LAP and in 8.1% for OPEN (p = 0.048). OS was 91.1% for LAP and 81.1% for OPEN (p = 0.360). DFS was 81.4% for LAP and 77.5% for OPEN (p = 0.923). Overall, LR was 2.3% without differences between groups.

Conclusions

Laparoscopic approach could affect the quality of surgical specimen due to technical aspects. However, if principles of surgical oncology are respected, minor pathologic differences in the quality of the mesorectum may not influence on the long-term oncologic outcomes.

Robotic total mesorectal excision or transanal total mesorectal excision meta-analysis

BACKGROUNDS

Total mesorectal excision (TME) has been established as the standard for oncologic resection of rectal cancer, and has a direct impact on local recurrence and overall survival.

OBJECTIVES

Our meta-analysis aims to evaluate the oncological outcomes of the newer techniques of TME - robotic TME versus Transanal TME (TaTME). Primary outcome measures included CRM positivity, R0 resection status, distal resection margins and lymph node yield. Secondary outcome measures were overall complication rates, anastomotic leak and wound infection rates, post-operative ileus rates and mean operative time.

METHODS

A systematic literature search was performed to identify relevant studies through PubMEd and Embase from January 2000 to January 2021. Inclusion criteria included English language articles directly comparing TaTME and robotic TME.

RESULTS

Seven hundred and fourteen studies were identified, and only six studies were included for this meta-analysis. A total of 1065 participants, of which 632 (59.3%) underwent robotic TME, and 433 (40.7%) had TaTME. Robotic TME had a statistically significant higher lymph node yield (SMD -0.53, p = 0.020). There were no significant differences in the overall complication rates, wound infection and anastomotic leak rates, post-operative ileus, mean operative time and CRM positivity.

CONCLUSION

This is the first meta-analysis assessing the outcomes of robotic TME versus TaTME, and only lymph node yield was statistically higher in robotic TME group. These techniques are potentially complementary rather than competing, and we believe that these two approaches can be adopted after appropriate training.

Predictors of Positive Circumferential Resection Margin in Rectal Cancer: A Current Audit of the National Cancer Database

BACKGROUND

Positive circumferential resection margin is a predictor of local recurrence and worse survival in rectal cancer. National programs aimed to improve rectal cancer outcomes were first created in 2011 and continue to evolve. The impact on circumferential resection margin during this time frame has not been fully evaluated in the United States.

OBJECTIVE

The purpose of this study was to determine the incidence and predictors of positive circumferential resection margin after rectal cancer resection, across patient, provider, and tumor characteristics.

DESIGN

This was a retrospective cohort study.

SETTINGS

The study was conducted using the National Cancer Database, 2011-2016.

PATIENTS

Adults who underwent proctectomy for pathologic stage I to III rectal adenocarcinoma were included.

MAIN OUTCOME MEASURES

Rate and predictors of positive circumferential resection margin, defined as resection margin ≤1 mm, were measured.

RESULTS

Of 52,620 cases, circumferential resection margin status was reported in 90% (n = 47,331) and positive in 18.4% (n = 8719). Unadjusted analysis showed that patients with positive circumferential resection margin were more often men, had public insurance and shorter travel, underwent total proctectomy via open and robotic approaches, and were treated in Southern and Western regions at integrated cancer networks (all p < 0.001). Multivariate analysis noted that positive proximal and/or distal margin on resected specimen had the strongest association with positive circumferential resection margin (OR = 15.6 (95% CI, 13.6-18.1); p < 0.001). Perineural invasion, total proctectomy, robotic approach, neoadjuvant chemoradiation, integrated cancer network, advanced tumor size and grade, and Black race had increased risk of positive circumferential resection margin (all p < 0.050). Laparoscopic approach, surgery in North, South, and Midwest regions, greater hospital volume and travel distance, lower T-stage, and higher income were associated with decreased risk (all p < 0.028).

LIMITATIONS

This was a retrospective cohort study with limited variables available for analysis.

CONCLUSIONS

Despite creation of national initiatives, positive circumferential resection margin rate remains an alarming 18.4%. The persistently high rate with predictors of positive circumferential resection margin identified calls for additional education, targeted quality improvement assessments, and publicized auditing to improve rectal cancer care in the United States. See Video Abstract at http://links.lww.com/DCR/B584.

PREDICTORES PARA UN MARGEN POSITIVO DE RESECCIN CIRCUNFERENCIAL EN EL CNCER DE RECTO UNA AUDITORA VIGENTE DE LA BASE DE DATOS NACIONAL DE CANCER

ANTECEDENTES:El margen positivo de resección circunferencial es un predictor de recurrencia local y peor sobrevida en el cáncer de recto. Los programas nacionales destinados a mejorar los resultados del cáncer de recto se crearon por primera vez en 2011 y continúan evolucionando. La repercusión del margen de resección circunferencial durante este período de tiempo no se ha evaluado completamente en los Estados Unidos.OBJETIVO:Determinar la incidencia y los predictores para un margen positivo de resección circunferencial posterior a la resección del cáncer de recto, según las características del paciente, el proveedor y el tumor.DISEÑO:Estudio de cohorte retrospectivo.AMBITO:Base de datos nacional de cáncer, 2011-2016.PACIENTES:Adultos que se sometieron a proctectomía por adenocarcinoma de recto con un estadío por patología I-III.PRINCIPALES VARIABLES EVALUADAS:Tasa y predictores para un margen positivo de resección circunferencial, definido como margen de resección ≤ 1 mm.RESULTADOS:De 52,620 casos, la condición del margen de resección circunferencial se informó en el 90% (n = 47,331) y positivo en el 18.4% (n = 8,719). El análisis no ajustado mostró que los pacientes con margen positivo de resección circunferencial se presentó con mayor frecuencia en hombres, tenían un seguro social y viajes más cortos, se operaron de proctectomía total abierta y robótica, y fueron tratados en las regiones del sur y el oeste en redes integradas de cáncer (todos p <0,001). El análisis multivariado destacó que el margen proximal y / o distal positivo de la pieza resecada tenía la asociación más fuerte con el margen postivo de resección circunferencial (OR 15,6; IC del 95%: 13,6-18,1, p <0,001). La invasión perineural, la proctectomía total, el abordaje robótico, la quimioradioterapia neoadyuvante, la red de cáncer integrada, el tamaño y grado del tumor avanzado y la raza afroamericana tenían un mayor riesgo de un margen de una resección positiva circunferencial (todos p <0,050). El abordaje laparoscópico, la cirugía en las regiones Norte, Sur y Medio Oeste, un mayor volumen hospitalario y distancia de viaje, estadio T más bajo y mayores ingresos se asociaron con una disminución del riesgo (todos p <0,028).LIMITACIONES:Estudio de cohorte retrospectivo con variables limitadas disponibles para análisis.CONCLUSIONES:A pesar del establecimiento de iniciativas nacionales, la tasa de margen positivo de resección circunferencial continúa siendo alarmante, 18,4%. El índice continuamente elevado junto a los predictores de un margen positivo de resección circunferencial hace un llamado para una mayor educación, evaluaciones específicas de mejora de la calidad y difusión de las auditorías para mejorar la atención del cáncer de recto en los Estados Unidos. Vea el resumen de video en http://links.lww.com/DCR/B584. Consulte Video Resumen en http://links.lww.com/DCR/B584.

Impact of Surgical Approach on Surgical Resection Quality in Mid- and Low Rectal Cancer, A Bayesian Network Meta-Analysis

Aim

To evaluate the evidence concerning the quality of surgical resection in laparoscopic (LapTME), robotic (RobTME) and transanal (TaTME) total mesorectal excision for mid-/low rectal cancer.

Methods

A systematic literature search of the PubMed, EMBASE and Cochrane Central Register of Controlled Trials databases was performed. A Bayesian network meta-analysis was utilized to compare surgical resection involved in these 3 surgical techniques by using ADDIS software. Rates of positive circumferential resection margins (CRMs) were the primary endpoint.

Results

A total of 34 articles, 2 randomized clinical trials (RCTs) and 32 non-RCTs, were included in this meta-analysis. Pooled data showed CRM positivity in 114 of 1763 LapTME procedures (6.5%), 54 of 1051 RobTME procedures (5.1%) and 60 of 1276 TaTME procedures (4.7%). There was no statistically significant difference among these 3 surgical approaches in terms of CRM involvement rates and all other surgical resection quality outcomes. The incomplete mesorectal excision rates were 9.6% (69/720) in the LapTME group, 1.9% (11/584) in the RobTME group and 5.6% (45/797) in the TaTME group. Pooled network analysis observed a higher but not statistically significant risk of incomplete mesorectum when comparing both LapTME with RobTME (OR = 1.99; 95% CI = 0.48-11.17) and LapTME with TaTME (OR = 1.90; 95% CI = 0.99-5.25). By comparison, RobTME was most likely to be ranked the best or second best in terms of CRM involvement, complete mesorectal excision, rate of distal resection margin (DRM) involvement and length of DRMs. In addition, RobTME achieved a greater mean tumor distance to the CRM than TaTME. It is worth noting that TaTME was most likely to be ranked the worst in terms of CRM involvement for intersphincteric resection of low rectal cancer.

Conclusion

Overall, RobTME was most likely to be ranked the best in terms of the quality of surgical resection for the treatment of mid-/low rectal cancer. TaTME should be performed with caution in the treatment of low rectal cancer.

Predictors of Surgical Difficulty in Laparoscopic Total Mesorectal Excision

Concerns have been raised regarding the oncological safety of laparoscopic total mesorectal excision (TME) as compared to an open approach. This study aimed to identify risk factors for surgically difficult laparoscopic TME. All consecutive laparoscopic rectal cancer cases were included from a prospectively maintained colorectal cancer database. The primary outcome was to identify risk factors for surgically difficult TME. A Surgical Difficulty Risk Score (SDRS) between 0 and 6 was calculated for each case with cases achieving an SDRS of 2 or greater being deemed as surgically difficult. A total of 2795 consecutive cases of laparoscopic TME were identified, with 464 (16.6%) surgically difficult cases. Univariate analysis found that operating in the male pelvis, performing abdomino-perineal resections, Hartmann’s procedures, and proctocolectomies were all significantly associated with higher operative difficulty (P < 0.001). A higher nodal stage of cancer (P = 0.046), and the resection of another organ (P = 0.003) were significantly associated with higher surgical difficulty. On multivariate analysis, a female pelvis was associated with a favorable laparoscopic resection (Odds ratio [OR] 0.54, 95% CI 0.43–0.67, P < 0.001), whereas patients who had another organ resection (OR 2.6, 95% CI 1.53–4.42, P < 0.001), nodal positivity (OR 1.37, 95% CI 1.11–1.69, P = 0.003), and high ASA scores had more difficult surgeries. Predictive factors for surgically difficult laparoscopic TME include male gender, high ASA scores, mid and low rectal cancer, positive nodal stage, and resection of another organ at time of surgery.

Colorectal Cancer Surgery Quality in Manitoba: A Population-Based Descriptive Analysis

Unwarranted clinical variation in healthcare impacts access, productivity, performance, and outcomes. A strategy proposed for reducing unwarranted clinical variation is to ensure that population-based data describing the current state of health care services are available to clinicians and healthcare decision-makers. The objective of this study was to measure variation in colorectal cancer surgical treatment patterns and surgical quality in Manitoba and identify areas for improvement. This descriptive study included individuals aged 20 years or older who were diagnosed with invasive cancer (adenocarcinoma) of the colon or rectum between 1 January 2010 and 31 December 2014. Laparoscopic surgery was higher in colon cancer (24.1%) compared to rectal cancer (13.6%). For colon cancer, the percentage of laparoscopic surgery ranged from 12.9% to 29.2%, with significant differences by regional health authority (RHA) of surgery. In 86.1% of colon cancers, ≥12 lymph nodes were removed. In Manitoba, the negative circumferential resection margin for rectal cancers was 96.9%, and ranged from 96.0% to 100.0% between RHAs. The median time between first colonoscopy and resection was 40 days for individuals with colon cancer. This study showed that high-quality colorectal cancer surgery is being conducted in Manitoba along with some variation and gaps in quality. As a result of this work, a formal structure for ongoing measuring and reporting surgical quality has been established in Manitoba. Quality improvement initiatives have been implemented based on these findings and periodic assessments of colorectal cancer surgery quality will continue.

[Robotic-assisted surgery of rectal cancer-Technique, limitations and results]

BACKGROUND

The number of oncological robotic-assisted rectal cancer resections is rapidly increasing in Germany and worldwide; however, the indications, technique and potential limitations of this surgical technique are still discussed.

MATERIAL AND METHODS

The standardized modular surgical technique, the results in our clinic and the currently published evidence are presented.

RESULTS

The procedure should be divided into seven modules in terms of standardization and teaching. After the learning curve there are principally no limitations or contraindications. The robotic-assisted approach is superior to open surgery in the following points: blood loss, lymph node harvest, negative circumferential resection margin (CRM), complication rate and length of hospital stay. In comparison to conventional laparoscopy the conversion rate and postoperative sexual and bladder function disorders are decreased. The operating time is longer.

CONCLUSION

Robotic-assisted rectal cancer resection is firmly established and standardized. The technique is superior to open surgery and conventional laparoscopy in some important aspects and is developing into the standard for this disease.

Surgical outcomes following colorectal cancer resections in patients aged 80 years and over: results from the Australia and New Zealand Binational Colorectal Cancer Audit

AIM

The primary aim was to compare the 30-day morbidity and mortality in patients aged ≥80 years undergoing surgery for colorectal cancer with those aged <80 years. The secondary aim was to identify independent outcome predictors.

METHOD

This was a retrospective study of patients undergoing surgery for colorectal cancer between January 2007 and February 2018. Patients were divided into those <80 years and those ≥80 years at the time of surgery. Data had been collected prospectively by the Australasian Binational Colorectal Cancer Audit and included patient demographics, site and stage of tumour, comorbidity, operative details, American Society of Anesthesiologists score (ASA), pathological staging, 30-day mortality and morbidity (medical and surgical). Univariate and multivariate analyses were used to identify predictors of 30-day morbidity and mortality.

RESULTS

During the study period, 4600 out of 20 463 (22.5%) patients were ≥80 years. They had a greater 30-day mortality after both colonic (97/2975 [3.3%] vs. 66/7010 [0.9%], P < 0.001) and rectal resections (50/1625 [3.1%] vs. 36/9006 [0.4%], P < 0.001) compared with younger patients. They also had an increased length of stay (colon cancer, 9 vs. 7 days; rectal cancer, 10 vs. 8 days; P < 0.001) and medical complications (colon cancer, 23.5% vs. 12.7%; rectal cancer, 25.2% vs. 11.2%; P < 0.001). Surgical complications were equivalent. Age ≥80 years was not an independent predictor of 30-day morbidity or mortality. Patients ≥80 years who were ASA 2/3 and had rectal cancer seemed to fare worse in terms of 30-day mortality (ASA 2, 22%, 95% CI 9%-36%, P < 0.001; ASA 3, 11%, 95% CI 4%-19%, P< 0.001).

CONCLUSIONS

Postoperative morbidity and mortality are significantly greater in patients ≥80 years undergoing colorectal cancer surgery. Any recommendation for surgery in this age group should take into account patient comorbidity and not be based on age alone.

Association of certification, improved quality and better oncological outcomes for rectal cancer in a specialized colorectal unit

PURPOSE

Centralization of cancer care is expected to yield superior results. In Germany, the national strategy is based on a voluntary certification process. The effect of centre certification is difficult to prove because quality data are rarely available prior to certification. This observational study aims to assess outcomes for rectal cancer patients before and after implementation of a certified cancer centre.

PATIENTS AND METHODS

All consecutive patients treated for rectal cancer in our certified centre from 2009 to 2017 were retrieved from a prospective database. The dataset was analyzed according to a predefined set of 19 quality indicators comprising 36 quality goals. The results were compared to an identical cohort of patients, treated from 2000 to 2008 just before centre implementation.

RESULTS

In total, 1059 patients were included, 481 in the 2009-2017 interval and 578 in the 2000-2008 interval. From 2009 to 2017, 25 of 36 quality goals were achieved (vs. 19/36). The proportion of anastomotic leaks in low anastomoses was improved (13.5% vs. 22.1%, p = 0.018), as was the local 5-year recurrence rate for stage (y)pIII rectal cancers (7.7% vs. 17.8%, p = 0.085), and quality of mesorectal excision (0.3% incomplete resections vs. 5.5%, p = 0.002). Furthermore, a decrease of abdominoperineal excisions was noted (47.1% vs. 60.0%, p = 0.037). For the 2009-2017 interval, local 5-year recurrence rate in stages (y)p0-III was 4.6% and 5-year overall survival was 80.2%.

CONCLUSIONS

Certification as specialized centre and regular audits were associated with an improvement of various quality parameters. The formal certification process has the potential to enhance quality of care for rectal cancer patients.

Abdominoperineal excision in Australasia: clinical outcomes, predictive factors and recent trends of nonrestorative rectal cancer surgery

AIM

The decision to perform an abdominoperineal excision (APR) rather than restorative bowel resection relies on a number of clinical factors. There remains great variability in APR rates internationally. The aim of this study was to demonstrate trends of APR surgery in low rectal cancer (< 6 cm from the anal verge) in Australasia and identify predictors of nonrestoration.

METHOD

This study reviewed a prospectively maintained colorectal registry - the Binational Colorectal Cancer Audit (BCCA) - from general/colorectal surgical units across Australia and New Zealand. Data were analysed to determine factors predictive of nonrestorative resection. Patients were analysed based on the presence (control) or absence (comparison) of a primary anastomosis.

RESULTS

Of 3628 patients with rectal cancer, 2096 were diagnosed with low rectal cancer between 2007 and 2017. The incidence of APR remained constant over the study period, with 58% of all resections of low rectal cancer being APR. The majority of resections were performed by consultants in urban hospitals (86% vs 14%). Tumours ≤ 3 cm from the anal verge, T4, M1 disease and neoadjuvant therapy were the greatest predictors of APR (P < 0.001). A significantly increased rate of restorative surgery was observed in public hospital settings (59% vs 41%, P < 0.05). The rate of positive circumferential resection margin (CRM) was 7.95%, with significantly increased rates in patients undergoing APR (12.2% vs 6.2%, P < 0.001). CRM positivity was increased in open approaches, T4, N2 and M1 staged disease and in an emergency/urgent setting (P < 0.001 and P < 0.045, respectively). Significantly increased wound and pulmonary complications were observed in the APR cohort (P < 0.01).

CONCLUSION

The rates of APR in Australia and New Zealand remain high but are comparable to international figures, with one-third of rectal cancers being treated by APR. The main determinants of APR are tumour height, T stage and neoadjuvant therapy requirement. CRM positivity was higher in APR patients.

Colorectal cancer in younger adults from a Bi-National Colorectal Cancer Audit registry

BACKGROUND

The incidence of colorectal cancer (CRC) in younger adults (<50 years old) is rising worldwide, at a rate of 1% per annum since mid-1980s. The clinical concern is that younger adults may have more advanced disease leading to poorer prognosis compared to their older cohort due to lack of screening. Therefore, the aim of this study is to assess the incidence and short-term outcomes of colorectal cancer in younger adults.

METHODS

This is a retrospective study from a prospectively maintained bi-national database from 2007 to 2018.

RESULTS

There were 1540 younger adults diagnosed with CRC, with a rise from 5.8% in 2007 to 8.4% in 2018. Majority had lower American Society of Anaesthesiologists (ASA) scores (89%), rectal cancers (46.1%) and higher tumour stage (65.4%). As a consequence, they were likely to have higher circumferential resection margin positivity (6%, P = 0.02) and to receive adjuvant chemotherapy (57.1%, P < 0.001) compared to their older cohort. Multivariate analysis showed disadvantaged socioeconomic status (odds ratio (OR) 3.3, 95% confidence interval (CI) 1.37-7.94, P < 0.001) and increasing tumour stage (OR 14.9, 95% CI 1.89-116.9, P < 0.001) were independent predictors for circumferential resection margin positivity whereas being female (OR 0.71, 95% CI 0.53-0.95, P = 0.02), higher ASA score (OR 175.3, 95% CI 26.7-1035.5, P < 0.001), urgent surgery (OR 2.75, 95% CI 1.84-4.11, P < 0.001) and anastomotic leak (OR 5.02, 95% CI 3.32-7.58, P < 0.001) were predictors of inpatient mortality.

CONCLUSION

There is a steady rise in the incidence of colorectal cancer in younger adults. Both physicians and younger adults should be aware of the potential risk of colorectal cancer (CRC) and appropriate investigations performed so not to delay the diagnosis.

Predictive Factors of Positive Circumferential and Longitudinal Margins in Early T3 Colorectal Cancer Resection

Background

Malignant involvement of circumferential resection margin (CRM) and longitudinal resection margin (LRM) after surgical resection of colorectal cancer (CRC) are associated with higher rates of recurrence and development of distant metastasis. This can influence the overall patient's prognosis. The aim of the current study was to identify pathological factors as predictors for the involvement of resection margins in early T3 CRC. Patients and Methods. Fifty patients radiologically diagnosed to have cT3a/b (CRC) were included in the study. After resection, the pathological examination was performed to identify patients with positive CRM and/or LRM. Relations between the different pathological parameters and the CMR and LRM involvements were assessed.

Results

Positive CRM was present in 17 cases (34%), while positive LRM was found in 6 cases (12%). The involvement of both margins was significantly associated with rectal tumors and tumors with infiltrative gross appearance, grade III, deeper invasion, and positive lymph node metastases. Also, there was a significant association between both margins' positivity and other pathological parameters as signet ring carcinoma, tumor budding, perineural and vascular invasion, high microvessel density (MVD), and sinusoidal vascular pattern, while the presence of necrosis and infiltrative advancing tumor front was significantly associated with CRM involvement only. The depth of tumor invasion and signet ring carcinoma were identified as independent predictor factors for positive CRM and LRM, respectively.

Conclusion

Preoperative identification of these pathological parameters can be a guide to tailor the management plan accordingly.

Transanal total mesorectal excision in the prone jackknife position without being conscious of the size of prostatic enlargement for lower rectal cancer

In 1982, it was demonstrated that a total mesorectal excision alone could achieve low rectal cancer recurrence rates in the pelvis and high disease-free survival rates. Nowadays, the total mesorectal excision is the gold-standard surgery for rectal cancer. Currently, the transanal total mesorectal excision has attracted attention as a promising alternative to the anterior approach. The transanal approach is superior to the anterior approach, because it facilitates total mesorectal excisions of the lower rectum, improves visualization, and shortens the surgical time. Some factors are particularly favorable for the transanal approach, including lesions in the lower third of the rectum, a narrow pelvis, a large tumor, male sex, and a prostatic enlargement. The transanal total mesorectal excision is commonly performed in the Lloyd-Davies position. However, in the Lloyd-Davies position, the sacral bone prevents the mobilized rectum from moving away from the pelvic base. From the perspective of pelvic morphology, we reasoned that, in the prone jackknife position, the mobilized rectum could spontaneously move toward the head, due to gravity, and this would broaden the pelvic surgical field. Consequently, this position could facilitate the transanal total mesorectal excision. Here, we described a transanal total mesorectal excision performed in the prone jackknife position for treating lower rectal cancer with a prostatic enlargement.

Impact of hospital geographic remoteness on short-term outcomes after colorectal cancer resection using state-wide administrative data

BACKGROUND

This study aimed to use validated coding algorithms, applied to a central repository of administrative data (AD), to report on short-term outcomes following resection for colorectal cancer (CRC) comparing regional to metropolitan Victorian hospitals.

METHODS

This is a retrospective cohort study using prospectively gathered AD. The primary outcome was prolonged length of stay (LOS). Secondary outcomes were: inpatient mortality, return to theatre, discharge destination and need for mechanical ventilation/intensive care unit support. Outcomes were adjusted for potential confounders via multivariable logistic regression analysis.

RESULTS

This study of 18 470 patients found strong evidence for lower odds of prolonged LOS (odds ratio (OR) 0.53, 95% confidence interval (CI) 0.48-0.58, P ≤ 0.001) and inpatient mortality (OR 0.67, 95% CI 0.49-0.91, P = 0.01) in inner regional hospital compared with metropolitan hospitals. For outer regional hospitals, there was strong evidence of decreased odds of prolonged LOS (OR 0.64, 95% CI 0.52-0.77, P = <0.001) and return to theatre (OR 0.67, 95% CI 0.47-0.95, P = 0.03).

CONCLUSION

This is the largest and most detailed study concerning short-term outcomes following CRC resection in Victorian public hospitals. Inner and outer regional centres had similar or better short-term outcomes than metropolitan hospitals after CRC resection. AD with validated algorithms serves as a large accurate database to report on CRC outcomes.

Improving quality of care and clinical outcomes for rectal cancer through clinical audits in a multicentre cancer care organisation

Introduction

Colorectal cancer treatment requires a complex, multidisciplinary approach. Because of the potential variability, monitoring through clinical audits is advisable. This study assesses the effects of a quality improvement action plan in patients with locally advanced rectal cancer and treated with radiotherapy.

Methods

Comparative, multicentre study in two cohorts of 120 patients each, selected randomly from patients diagnosed with rectal cancer who had initiated radiotherapy with a curative intent. Based on the results from a baseline clinical audit in 2013, a quality improvement action plan was designed and implemented; a second audit in 2017 evaluated its impact.

Results

Standardised information was present on 77.5% of the magnetic resonance imaging (MRI) staging reports. Treatment strategies were similar in all three study centres. Of the patients whose treatment was interrupted, just 9.7% received a compensation dose. There was an increase in MRI re-staging from 32.5 to 61.5%, and a significant decrease in unreported circumferential resection margins following neoadjuvant therapy (ypCRM), from 34.5 to 5.6% (p <  0.001).

Conclusions

The comparison between two clinical audits showed improvements in neoadjuvant radiotherapy in rectal cancer patients. Some indicators reveal areas in need of additional efforts, for example to reduce the overall treatment time.

Reconsideration of the Safety of Laparoscopic Rectal Surgery for Cancer

The oncological outcomes of laparoscopic rectal cancer surgery were evaluated in recent multicenter randomized clinical trials (RCTs). The MRC-CLASSIC, COLOR II, and COREAN trials found no differences in local recurrence or diseasefree survival rate between laparoscopic and open surgery. However, the noninferiority of laparoscopic surgery with respect to open surgery for rectal cancer was not established on statistical analysis in the ACOSOG Z6051 and the ALaCaRT trials. Quality of total mesorectal excision (TME) is one of the most important prognostic factors. Incomplete TME had unfavorable oncologic outcomes compared to complete TME. Although TME quality can be clearly identified on pathologic evaluation, there is controversy regarding the acceptable range of oncologically safe TME for laparoscopic surgery. It is not certain whether near-complete TME has an unfavorable oncologic impact and whether laparoscopic surgery with near-complete TME is an oncological threat. Therefore, the surgical community will be interested in the long-term outcomes and meta-analyses of ongoing large-scale RCTs. Laparoscopic rectal cancer surgery has been steadily improving its safety for oncology surgery, which has been reported consistently in various multicenter RCTs. To improve surgical quality, colorectal surgeons should choose the most appropriate surgical technique, including laparoscopic surgery.

Impact of Preoperative Care for Rectal Adenocarcinoma on Pathologic Specimen Quality and Postoperative Morbidity: A NSQIP Analysis

BACKGROUND

Comprehensive and multidisciplinary care are critical in rectal cancer treatment. We sought to determine if completeness of preoperative care was associated with pathologic specimen quality and postoperative morbidity.

STUDY DESIGN

Clinical stage I-III rectal adenocarcinoma patients who underwent elective low anterior resection or abdominoperineal resection were identified from the 2016-2017 American College of Surgeons-National Surgical Quality Improvement Project (ACS-NSQIP) database. The 3 preoperative NSQIP variables (colonoscopy, stoma marking, and neoadjuvant chemoradiation) were used to divide patients into 2 cohorts: complete vs incomplete preoperative care. The primary outcome was a composite higher pathologic specimen quality score (>12 lymph nodes, negative circumferential, and negative distal margins). The secondary outcome was 30-day morbidity. Preoperative characteristics were compared with ANOVAs and chi-square tests. Outcomes measures were evaluated with logistic regression.

RESULTS

We identified 1,125 patients: 591 (52.5%) complete and 534 (47.5%) incomplete. The complete group was younger, had more women, lower-third rectal tumors, clinical stage III disease, and neoadjuvant treatment. The complete group had higher odds of better pathologic specimen quality after adjusting for age, sex, tumor location, stage, and neoadjuvant therapy (adjusted odds ratio [aOR] 1.75, p = 0.001). The complete group had decreased rates of transfusions (odds ratio [OR] 0.47, p < 0.001), postoperative ileus (OR 0.67, p = 0.01), sepsis (OR 0.32, p = 0.01), and readmissions (OR 0.60, p = 0.003). Other complications did not statistically differ between groups.

CONCLUSIONS

Complete preoperative care in rectal adenocarcinoma is associated with higher pathologic specimen quality and reduced postoperative morbidity. This highlights the importance of adherence to guideline-directed care.

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.

Hospital and surgeon variation in positive circumferential resection margin among rectal cancer patients

BACKGROUND

The objective of this study was to evaluate variation in positive CRM at the surgeon and hospital levels and assess impact on disease-specific survival.

METHODS

Patients with stage I-III rectal cancer were identified in New York State. Bayesian hierarchical regressions estimated observed-to-expected (O/E) ratios for each surgeon/hospital. Competing-risks analyses estimated disease-specific survival among patients who were treated by surgeons/hospitals with O/E > 1 compared to those with O/E ratio ≤ 1.

RESULTS

Among 1,251 patients, 208 (17%) had a positive CRM. Of the 345 surgeons and 118 hospitals in the study, 99 (29%) and 48 (40%) treated a higher number of patients with CRM than expected, respectively. Patients treated by surgeons with O/E > 1 (HR = 1.38, 95% CI = 1.16, 1.67) and those treated at hospitals with O/E > 1 (HR = 1.44, 95% CI = 1.11, 1.85) had worse disease-specific survival.

DISCUSSION

Surgeon and hospital performance in positive CRM is associated with worse prognosis suggesting opportunities to enhance referral patterns and standardize care.