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.

Session 4: What should we do for poor responders after chemoradiotherapy: bad biology or should the fight go on?

Just over 50% of patients with advanced rectal cancer have a poor response to chemoradiotherapy with resultant poor outcomes. Professor Glimelius reviews the evidence base for defining such patients and the potential role, if any, of further treatment.

Interobserver agreement of radiologists assessing the response of rectal cancers to preoperative chemoradiation using the MRI tumour regression grading (mrTRG).

AIM: To investigate whether the magnetic resonance imaging (MRI) tumour regression grading (mrTRG) scale can be taught effectively resulting in a clinically reasonable interobserver agreement (>0.4; moderate to near perfect agreement). MATERIALS AND METHODS: This study examines the interobserver agreement of mrTRG, between 35 radiologists and a central reviewer. Two workshops were organised for radiologists to assess regression of rectal cancers on MRI staging scans. A range of mrTRGs on 12 patient scans were used for assessment. RESULTS: Kappa agreement ranged from 0.14-0.82 with a median value of 0.57 (95% CI: 0.37-0.77) indicating good overall agreement. Eight (26%) radiologists had very good/near perfect agreement (κ>0.8). Six (19%) radiologists had good agreement (0.8≥κ>0.6) and a further 12 (39%) had moderate agreement (0.6≥κ>0.4). Five (16%) radiologists had a fair agreement (0.4≥κ>0.2) and two had poor agreement (0.2>κ). There was a tendency towards good agreement (skewness: 0.92). In 65.9% and 90% of cases the radiologists were able to correctly highlight good and poor responders, respectively. CONCLUSIONS: The assessment of the response of rectal cancers to chemoradiation therapy may be performed effectively using mrTRG. Radiologists can be taught the mrTRG scale. Even with minimal training, good agreement with the central reviewer along with effective differentiation between good and intermediate/poor responders can be achieved. Focus should be on facilitating the identification of good responders. It is predicted that with more intensive interactive case-based learning a κ>0.8 is likely to be achieved. Testing and retesting is recommended.

A meta-analysis assessing the survival implications of subclassifying T3 rectal tumours.

AIM: Although T3 tumour subclassifications have been linked to prognosis, its mandatory adoption in histopathological reports has not been incorporated. This article focusses on the survival outcomes in patients with T3 rectal cancer according to extramural spread beyond the muscularis propria. METHODS: A systematic review of all studies up to January 2016, without language restriction, was identified from MEDLINE, Cochrane Controlled Trials Register (1960-2016) and Embase (1991-2016). All studies reporting on survival and T3 tumours with a defined cut-off of 5 mm ± 1 mm tumour invasion beyond the muscularis propria for rectal cancers were included. Hazard ratios were extracted directly from the studies or from survival curves using the technique described by Parmar. Quality assessment was performed using the Newcastle-Ottawa scale. RESULTS: Tumours with invasion more than 5 ± 1 mm from the muscularis propria had statistically significantly worse overall survival (natural log of the hazard ratio [lnHR]: 1.40 [1.06, 2.04], p < 0.001) and there was no statistically significant heterogeneity (χ2 = 1.541, df = 3, p = 0.673, I2 = 0). There was statistically significantly worse disease-free survival in more invasive tumours (lnHR: 1.49 [1.19, 2.00], p < 0.001) and cancer specific survival (lnHR: 1.22 [0.917, 1.838], p < 0.001). Overall survival in patients who had preoperative therapy was higher in patients with less invasion beyond the muscularis propria [p < 0.01]. CONCLUSIONS: Subclassifying all T3 rectal tumours according to the depth of spread with a cut-off of 5±1 mm beyond the muscularis propria is prognostically relevant for overall survival, disease-free survival and cancer-specific survival irrespective of the nodal status; therefore, subclassifying T3 tumours should be a reporting requirement in histopathology reports.

A novel method for intra-operative colonic decompression without contamination.

The need for intra-operative colonic decompression is commonplace within general surgical theatre. However, cases are usually complex, present late and the risk of perforation with subsequent contamination is high. We describe a novel technique for closed decompression using a laparoscopic trocar and standard pool sucker in a 78-year-old gentleman with an obstructing sigmoid tumour.