Modern management of colorectal cancer--a pathologist's view

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.

Pathologist's perspective on primary rectal cancer

Evaluation of primary rectal cancer specimens places the pathologist in a unique position relative to peers, as it is one of the few specimens where the report influences not just patient outcomes but also the quality of the surgical technique itself. With ever-increasing data indicating that the completeness of the mesorectal excision and adequate resection margins are critical for reduced local recurrence rates and improved clinical outcome, the pathologist is faced with the challenge of implementing methods to optimize the evaluation of primary rectal cancers.

Clinical practice guidelines for the surgical treatment of rectal cancer: a consensus statement of the Hellenic Society of Medical Oncologists (HeSMO)

In rectal cancer management, accurate staging by magnetic resonance imaging, neo-adjuvant treatment with the use of radiotherapy, and total mesorectal excision have resulted in remarkable improvement in the oncological outcomes. However, there is substantial discrepancy in the therapeutic approach and failure to adhere to international guidelines among different Greek-Cypriot hospitals. The present guidelines aim to aid the multidisciplinary management of rectal cancer, considering both the local special characteristics of our healthcare system and the international relevant agreements (ESMO, EURECCA). Following background discussion and online communication sessions for feedback among the members of an executive team, a consensus rectal cancer management was obtained. Statements were subjected to the Delphi methodology voting system on two rounds to achieve further consensus by invited multidisciplinary international experts on colorectal cancer. Statements were considered of high, moderate or low consensus if they were voted by ≥80%, 60-80%, or <60%, respectively; those obtaining a low consensus level after both voting rounds were rejected. One hundred and two statements were developed and voted by 100 experts. The mean rate of abstention per statement was 12.5% (range: 2-45%). In the end of the process, all statements achieved a high consensus. Guidelines and algorithms of diagnosis and treatment were proposed. The importance of centralization, care by a multidisciplinary team, adherence to guidelines, and personalization is emphasized.

Robotic transanal surgery for local excision of rectal neoplasia, transanal total mesorectal excision, and repair of complex fistulae: clinical experience with the first 18 cases at a single institution

BACKGROUND

Robotic transanal surgery represents a natural evolution of transanal minimally invasive surgery. This new approach to rectal surgery provides the ability to perform local excision of rectal neoplasia with precision. Robotic transanal surgery can also be used to perform more advanced procedures including repair of complex fistulae and transanal total mesorectal excision.

METHODS

Data from patients who underwent transanal robotic surgery over a 33-month period were retrospectively reviewed. Patients underwent three types of procedures using this approach: (a) local excision of rectal neoplasia, (b) transanal total mesorectal excision, and (c) closure of complex fistulae, such as rectourethral fistulae.

RESULTS

Eighteen patients underwent robotic transanal surgery during the 33-month study period. Of these, nine patients underwent local excision of rectal neoplasia; four patients underwent transanal total mesorectal excision; four patients underwent repair of rectourethral fistulae; and one patient underwent repair of an anastomotic fistula. Of the patients undergoing robotic transanal surgery for local excision, 6/9 were resections of benign neoplasia, while 3/9 were resections for invasive adenocarcinoma. There was no fragmentation (0/9) noted on any of the locally excised specimens, while one patient (1/9) had a positive lateral margin. During the mean follow-up of 11.4 months, no recurrence was detected. Four patients underwent robotic-assisted transanal total mesorectal excision for curative intent resection of rectal cancer confined to the distal rectum. Mesorectal quality was graded as complete or near complete, and an R0 resection was performed in all four cases. Other transanal robotic procedures performed were the repair of rectourethral fistulae (n = 3) and anastomotic fistula (n = 1). This approach was met with limited success, and only half of the rectourethral fistulae were closed.

CONCLUSIONS

Robotic transanal surgery for local excision, transanal total mesorectal excision, and repair of fistulae is feasible, although these new approaches represent a work-in-progress. Improvement in platform design will likely facilitate the ability to perform more complex procedures. Further research with robotic transanal approaches is necessary to determine whether or not this approach can provide patients with significant benefit.

Predicting the pathological features of the mesorectum before the laparoscopic approach to rectal cancer

Pelvic anatomy and tumour features play a role in the difficulty of the laparoscopic approach to total mesorectal excision in rectal cancer. The aim of the study was to analyse whether these characteristics also influence the quality of the surgical specimen. We performed a prospective study in consecutive patients with rectal cancer located less than 12 cm from the anal verge who underwent laparoscopic surgery between January 2010 and July 2013. Exclusion criteria were T1 and T4 tumours, abdominoperineal resections, obstructive and perforated tumours, or any major contraindication for laparoscopic surgery. Dependent variables were the circumferential resection margin (CMR) and the quality of the mesorectum. Sixty-four patients underwent laparoscopic sphincter-preserving total mesorectal excision. Resection was complete in 79.1% of specimens and CMR was positive in 9.7%. Univariate analysis showed tumour depth (T status) (P = 0.04) and promontorium-subsacrum angle (P = 0.02) independently predicted CRM (circumferential resection margin) positivity. Tumour depth (P < 0.05) and promontorium-subsacrum axis (P < 0.05) independently predicted mesorectum quality. Multivariate analysis identified the promontorium-subsacrum angle (P = 0.012) as the only independent predictor of CRM. Bony pelvis dimensions influenced the quality of the specimen obtained by laparoscopy. These measurements may be useful to predict which patients will benefit most from laparoscopic surgery and also to select patients in accordance with the learning curve of trainee surgeons.

Rectal Cancer: MR imaging of the mesorectal fascia and effect of chemoradiation on assessment of tumor involvement

PURPOSE

To evaluate the impact of chemoradiation on the reliability of MRI in assessing tumor involvement of the mesorectal fascia in patients with rectal cancer.

MATERIALS AND METHODS

Presurgical MRI was performed in 150 patients; among them 85 had received neoadjuvant long-course chemoradiation. A standardized imaging protocol (1.5 Tesla [T] system, image voxel size 0.6 × 0.4 × 3 mm(3) ), standardized surgery, and histopathological examination were applied for the entire patient population. Images were analyzed to identify potential tumor involvement of the mesorectal fascia (minimum tumor distance to fascia ≤1 mm) and compared with histopathology as the reference standard. Results of nonirradiated and irradiated patients were compared to define the impact of chemoradiation on imaging reliability.

RESULTS

In nonirradiated patients, MRI was reliable in predicting or excluding tumor involvement of the mesorectal fascia, positive predictive value 80%, negative predictive value 89%. The frequency of overestimating tumor involvement was significantly higher in irradiated patients (P = 0.005, positive predictive value 42%).

CONCLUSION

Discussions about MRI assessment of tumor involvement of the mesorectal fascia as a basis for recommending neoadjuvant chemoradiation should focus on investigations that excluded irradiated patients, because MRI is less reliable after chemoradiation and tends to overestimate mesorectal tumor involvement.

Factors influencing the quality of total mesorectal excision

BACKGROUND

Total mesorectal excision (TME) has become the standard of care for rectal cancer. Incomplete TME may lead to local recurrence.

METHODS

Data from the multicentre observational German Quality Assurance in Rectal Cancer Trial were used. Patients undergoing low anterior resection for rectal cancer between 1 January 2005 and 31 December 2009 were included. Multivariable analysis using a stepwise logistic regression model was performed to identify predictors of suboptimal TME.

RESULTS

From a total of 6179 patients, complete data sets for 4606 patients were available for analysis. Pathological tumour category higher than T2 (pT3 versus pT1/2: odds ratio (OR) 1.22, 95 per cent confidence interval 1.01 to 1.47), tumour distance from the anal verge less than 8 cm (OR 1.27, 1.05 to 1.53), advanced age (65-80 years: OR 1.25, 1.03 to 1.52; over 80 years: OR 1.60, 1.15 to 2.22), presence of intraoperative complications (OR 1.63, 1.15 to 2.30), monopolar dissection technique (OR 1.43, 1.14 to 1.79) and low case volume (fewer than 20 procedures per year) of the operating surgeon (OR 1.20, 1.06 to 1.36) were independently associated with moderate or poor TME quality.

CONCLUSION

TME quality was influenced by patient- and treatment-related factors.

MRI-based indications for neoadjuvant radiochemotherapy in rectal carcinoma: interim results of a prospective multicenter observational study

BACKGROUND

This study evaluated use of circumferential resection margin status in preoperative MRI (mrCRM) as an indication for neoadjuvant radiochemotherapy (nRCT) in rectal carcinoma patients.

MATERIALS AND METHODS

In a multicenter prospective study, nRCT was given to patients with carcinoma of the middle rectum with positive mrCRM (≤1 mm), with cT3 low rectal carcinoma, and all patients with cT4 tumors. The short-term endpoints were pathologic pCRM (≤1 mm) as a strong predictor of local recurrence rate and the quality of total mesorectal excision according to the plane of surgery. These endpoints were compared in patients with and without nRCT.

RESULTS

Of 230 patients that met the inclusion criteria, 96 (41.7%) received a long course of nRCT and 134 (58.3%) were primarily operated on. The pCRM was positive in 13 of 230 (5.7%) (primarily operated on, 2 of 134 [1.5%]; after nRCT, 11 of 96 [11%]). In 1 of 134 (0.7%) case, the mrCRM was falsely negative. Patients at participating centers varied in terms of preoperative stage but not in pCRM positivity (0%-13%, P = .340). The plane of surgery was mesorectal (good) in 209 of 230 (90.9%), intramesorectal (moderate) in 16 of 230 (7%), and the muscularis propria plane (poor) in 2.2% (5 of 230).

CONCLUSIONS

Low pCRM positivity and the high quality of mesorectal excision support use of MRI-based nRCT in rectal carcinoma. nRCT was avoidable in 45% of patients with stage II and III disease without significant risk of undertreatment. Preoperative MRI thus allows identification of patients with high risk of local recurrence and use of selective nRCT.

Individualized magnetic resonance imaging-based neoadjuvant chemoradiation for middle and lower rectal carcinoma

AIM

In most institutions neoadjuvant chemoradiation for middle and lower rectal carcinoma is currently given to patients with tumours of clinical stages II or III (cT3,4 and/or N1,2). The possibility of a reduction in the use of neoadjuvant chemoradiation by an individualized magnetic resonance imaging (MRI)-based indication for neoadjuvant chemoradiation was analysed.

METHOD

Assessment of the pathological and oncological principles indicating for neoadjuvant treatment was used to determine the prognostic importance of the distance between the tumour and the circumferential resection margin and pretherapeutic assessment using modern MRI.

RESULTS

Based on the results of pretreatment MRI scanning, a proposal is presented for the treatment of middle and lower rectal carcinoma with neoadjuvant chemoradiation. Adopting this proposal, the frequency of neoadjuvant chemoradiation decreased from 70% to 35% and the early and late adverse effects of this therapy were reduced. In contrast, the expected locoregional recurrence rate increased from 6% to 11% if all quality criteria were met and to 18% if not.

CONCLUSION

An MRI-based indication for neoadjuvant chemoradiation is justified only for centres with regular quality assurance of MRI, surgery, radiotherapy and pathology. The proposal needs confirmation by long-term follow up and by prospective studies with larger numbers of patients.

Quality management in rectal carcinoma: what is feasible?

PURPOSE

A cohort study was carried out to analyse quality indicators in the diagnosis and treatment of rectal carcinoma.

METHODS

A total of 2,470 patients with rectal carcinoma treated between 1985 and 2007 at the Department of Surgery, University of Erlangen, were analysed and compared within four time intervals.

RESULTS

Most of the indicators analysed from 2004 to 2007 fulfilled the defined target values. The indicators for process quality of surgical treatment and the surrogate indicators of outcome quality in surgery showed excellent results. Comparing this to previous data, it displays the new developments such as introduction of multimodal treatment for high-risk patients. While the rate of locoregional recurrences decreased, no significant improvement in survival was found.

CONCLUSIONS

Careful analysis of quality indicators is important for both quality management and comparison of treatment results. The progress in diagnosis and treatment requires a continuous update of definitions and target values.

Magnetic resonance imaging (MRI)-based indication for neoadjuvant treatment of rectal carcinoma and the surrogate endpoint CRM status

AIM

Is it possible to reduce the frequency of neoadjuvant therapy for rectal carcinoma and nevertheless achieve a rate of more than 90% circumferential resection margin (CRM)-negative resection specimens by a novel concept of magnetic resonance imaging (MRI)-based therapy planning?

MATERIALS AND METHODS

One hundred eighty-one patients from Berlin and Mainz, Germany, with primary rectal carcinoma, without distant metastasis, underwent radical surgery with curative intention. Surgical procedures applied were anterior resection with total mesorectal excision (TME) or partial mesorectal excision (PME; PME for tumours of the upper rectum) or abdominoperineal excision with TME.

RESULTS

With MRI selection of the highest-risk cases, neoadjuvant therapy was given to only 62 of 181 (34.3%). The rate of CRM-negative resection specimens on histology was 170 of 181 (93.9%) for all patients, and in Berlin, only 1 of 93 (1%) specimens was CRM-positive. Patients selected for primary surgery had CRM-negative specimens on histology in 114 of 119 (95.8%). Those selected for neoadjuvant therapy had a lower rate of clear margin: 56 of 62 (90%).

CONCLUSION

By applying a MRI-based indication, the frequency of neoadjuvant treatment with its acute and late adverse effects can be reduced to 30-35% without reduction of pathologically CRM-negative resection specimens and, thus, without the danger of worsening the oncological long-term results. This concept should be confirmed in prospective multicentre observation studies with quality assurance of MRI, surgery and pathology.

Distribution of lymph nodes in the mesorectum: how deep is TME necessary?

BACKGROUND

Standardization of total mesorectal excision (TME) had a great impact on decreasing local recurrence rates for the treatment of rectal cancer. However, exact numbers and distribution of lymph nodes (LN) along the mesorectum remains controversial with some studies suggesting that few LNs are present in the distal third of the mesorectum.

METHODS

Eighteen fresh cadavers without a history of rectal cancer were studied. The rectum was removed by TME and then was divided into right lateral, posterior and left lateral sides, which were further subdivided into 3 levels (upper, middle and lower). A pathologist determined the number and sizes of the LNs in each of the nine areas, b linded to their anatomical origin.

RESULTS

Overall, the mesorectum had a mean of 5.7 LNs (SD=3.7) and on average each LN had a maximum diameter of 3.0 mm (SD=2.7). There was no association between the mean number or size of LNs with gender, BMI, or age. There was a significantly higher prevalence of LNs in the posterior location (2.8 per mesorectum) than in the two lateral locations (0.8 and 1.2 per mesorectum; p=0.02). The distribution of LNs in the three levels of the rectum was not significant.

CONCLUSIONS

The distribution of LNs reinforces the fact that TME should always include the distal third of the mesorectum. Care must be taken to not violate the posterior aspect of the mesorectum.

Extramural Depth of Tumor Invasion at Thin-Section MR in Patients with Rectal Cancer: Results of the MERCURY Study

PURPOSE

To prospectively evaluate the accuracy of magnetic resonance (MR) imaging in depicting the extramural depth of tumor invasion in patients who have rectal cancer, with histopathologic results as the reference standard.

MATERIALS AND METHODS

The Magnetic Resonance Imaging and Rectal Cancer European Equivalence (MERCURY) Study received ethics approval from all participating centers, and all patients gave informed consent. Consecutive patients (n = 679) with adenocarcinoma of the rectum consented to participate. Imaging workshops for participating specialist gastrointestinal radiologists were held to ensure standardization of image acquisition techniques. Standardized MR image interpretation and data reporting were performed by using previously validated criteria. MR images were prospectively singly read by the specialist gastrointestinal radiologists. The maximal extramural depth (EMD) of tumor spread, defined at histopathologic analysis as the distance from the outer edge of the longitudinal muscularis propria to the outer edge of the tumor, was measured and recorded. The maximal EMD was the reference standard. The MR and histopathologic results were considered to be equivalent when the 95% confidence interval of the difference between them was within +/-0.5 mm.

RESULTS

Tumor EMD measurements obtained at both MR imaging and histopathologic analysis were available for 295 (95%) of 311 patients after primary surgery. Mean EMDs were 2.80 mm +/- 4.60 (standard deviation) and 2.81 mm +/- 4.28 at MR imaging and histopathologic analysis, respectively. The mean difference between the MR-derived and histopathologically derived EMDs was -0.05 mm +/- 3.85 (95% confidence interval: -0.49 mm, 0.40 mm). Therefore, MR and histopathologic assessments of tumor spread were considered equivalent to within 0.5 mm.

CONCLUSION

Demonstration of accurate measurement of the depth of extramural tumor spread in the MERCURY Study enabled accurate preoperative prognostication.

Optimised surgery (so-called TME surgery) and high-resolution MRI in the planning of treatment of rectal carcinoma

BACKGROUND

Since November 1998, we have applied the concept of total mesorectal excision (TME) to rectal carcinoma together with a standardised pathological quality assessment. Participation in the European MERCURY study [The MERCURY Study Group Radiology (in press), 2006] required us to establish the indication for neoadjuvant radiochemotherapy on the basis of an magnetic resonance imaging (MRI) scan. The aim of the present retrospective study is to evaluate the quality of the surgery, the efficacy of the MRI and the oncological outcomes achieved.

MATERIALS AND METHODS

Between November 2001 and October 2005, 68 out of 109 patients with carcinoma of the rectum were submitted to radical surgery in curative intent and 23/68 (34%) were given neoadjuvant therapy. In an interdisciplinary study group, each patient was evaluated pre-operatively and post-operatively using standardised MRI and histopathological methods.

RESULTS

The quality of surgery was established on the basis of the pathological examination of the surgical specimen. The rates of incomplete mesorectal excision, intra-operative tumour cell dissemination and positive circumferential margins were all low at 4%, 7% and 3%, respectively. The effectiveness of MRI proved to be greatest in predicting the tumour status at the circumferential resection margin: in the admittedly limited number of patients it proved possible to correctly predict the tumour status for every patient. The assessment of the anatomic extent of the primary tumour and of the regional lymph node metastasis according to the TNM system, in contrast, was considerably less successful at 73% and 75%, and 37% and 57%, respectively.

CONCLUSION

By applying the TME concept and MRI-based therapy planning, excellent results can be achieved and, at the same time, the number of patients requiring neoadjuvant treatment is considerably reduced.

Diagnostic accuracy of preoperative magnetic resonance imaging in predicting curative resection of rectal cancer: prospective observational study

OBJECTIVE

To assess the accuracy of preoperative staging of rectal cancer with magnetic resonance imaging to predict surgical circumferential resection margins.

DESIGN

Prospective observational study of rectal cancers treated by colorectal multidisciplinary teams between January 2002 and October 2003.

SETTING

11 colorectal units in four European countries.

PARTICIPANTS

408 consecutive patients presenting with all stages of rectal cancer and undergoing magnetic resonance imaging before total mesorectal excision surgery and histopathological assessment of the surgical specimen.

MAIN OUTCOME MEASURES

Accuracy of magnetic resonance imaging in predicting a curative resection based on the histological yardstick of presence or absence of tumour at the margins of the specimen.

RESULTS

354 of the 408 patients had a clear circumferential resection margin (87%, 95% confidence interval 83% to 90%). Specificity for prediction of a clear margin by magnetic resonance imaging was 92% (327/354, 90% to 95%). High resolution scans were technically satisfactory in 93% (379/408). Surgical specimens were histopathologically graded as complete or moderate in 80% (328/408), and the median lymph node harvest was 12 (range 0-49). Magnetic resonance imaging predicted clear margins in 349 patients. At surgery 327 had clear margins (94%, 91% to 96%).

CONCLUSION

High resolution magnetic resonance imaging accurately predicts whether the surgical resection margins will be clear or affected by tumour. This technique can be reproduced accurately in multiple centres to predict curative resection and warns the multidisciplinary team of potential failure of surgery, thus enabling selection of patients for preoperative treatment.

Diagnostic accuracy of preoperative magnetic resonance imaging in predicting curative resection of rectal cancer: prospective observational study

OBJECTIVE

To assess the accuracy of preoperative staging of rectal cancer with magnetic resonance imaging to predict surgical circumferential resection margins.

DESIGN

Prospective observational study of rectal cancers treated by colorectal multidisciplinary teams between January 2002 and October 2003.

SETTING

11 colorectal units in four European countries.

PARTICIPANTS

408 consecutive patients presenting with all stages of rectal cancer and undergoing magnetic resonance imaging before total mesorectal excision surgery and histopathological assessment of the surgical specimen.

MAIN OUTCOME MEASURES

Accuracy of magnetic resonance imaging in predicting a curative resection based on the histological yardstick of presence or absence of tumour at the margins of the specimen.

RESULTS

354 of the 408 patients had a clear circumferential resection margin (87%, 95% confidence interval 83% to 90%). Specificity for prediction of a clear margin by magnetic resonance imaging was 92% (327/354, 90% to 95%). High resolution scans were technically satisfactory in 93% (379/408). Surgical specimens were histopathologically graded as complete or moderate in 80% (328/408), and the median lymph node harvest was 12 (range 0-49). Magnetic resonance imaging predicted clear margins in 349 patients. At surgery 327 had clear margins (94%, 91% to 96%).

CONCLUSION

High resolution magnetic resonance imaging accurately predicts whether the surgical resection margins will be clear or affected by tumour. This technique can be reproduced accurately in multiple centres to predict curative resection and warns the multidisciplinary team of potential failure of surgery, thus enabling selection of patients for preoperative treatment.

Low rectal cancer: a call for a change of approach in abdominoperineal resection

PURPOSE

Despite the major improvements that have been made due to total mesorectal excision (TME), low rectal cancer still remains a challenge.

METHODS

By investigating a prospective randomized rectal cancer trial in which surgeons had undergone training in TME the factors responsible for the poor outcome were determined and a new method for assessing the quality of surgery was tested.

RESULTS

Survival differed greatly between abdominoperineal resection (APR) and anterior resection (AR; 38.5% v 57.6%, P = .008). Low rectal carcinomas have a higher frequency of circumferential margin involvement (26.5% v 12.6%, P < .001). More positive margins were present in the patients operated with APR (30.4%) compared to AR (10.7%, P = .002). Furthermore, more perforations were present in these specimens (13.7% v 2.5%, P < .001). The plane of resection lies within the sphincteric muscle, the submucosa or lumen in more than 1/3 of the APR cases, and in the remainder lay on the sphincteric muscles.

CONCLUSION

We systematically described and investigated the pathologic properties of low rectal cancer in general, and APR in particular, in a prospective randomized trial including surgeons who had been trained in TME. The poor prognosis of the patients with an APR is ascribed to the resection plane of the operation leading to a high frequency of margin involvement by tumor and perforation with this current surgical technique. The clinical results of this operation could be greatly improved by adopting different surgical techniques and possibly greater use of radiochemotherapy.

MRI assessment of the bony pelvis may help predict resectability of rectal cancer

OBJECTIVE

The outcome after surgical treatment of rectal cancer may be influenced by the technical difficulty of the operation, which is thought to be affected by pelvic size. The aim of this study was to examine the association between bony pelvic dimensions and CRM involvement.

PATIENTS AND METHODS

All patients with primary rectal cancer between December 1999 and January 2002 were studied. Staging was performed by pelvic MRI. Nine pelvic dimensions were measured from the MR images on a workstation. Pathology reports were obtained for all patients and the mesorectal specimen was examined. Technical difficulty was assessed by circumferential resection margin (CRM) involvement.

RESULTS

Of 126 patients with primary rectal cancer, 88 had staging MRI and rectal excision; there were significant differences between the sexes in all 9 pelvic dimensions (P < 0.05). In females, the interspinous diameter was significantly shorter in patients with CRM involvement compared with patients with a negative CRM. In female patients predicted to have a negative CRM, the anteroposterior diameter of the inlet, the anteroposterior diameter of the midplane and the transverse diameter of the midplane (interspinous distance) were significantly shorter in patients who actually had a positive CRM compared with those in whom the CRM was negative. In male patients, there was no correlation between pelvic dimensions and CRM status.

CONCLUSIONS

In certain patients with rectal cancer, CRM positivity may be predicted from pre-operative MRI pelvic measurements. This may influence the choice of adjuvant therapy.

Training and quality assurance for rectal cancer: 20 years of data is enough

Rectal cancer is a common disease with a high rate of mortality. During the past 20 years, substantial improvements have been made in the surgical, pathological, radiological, and oncological approaches used to treat this disease, but there is good evidence for continuing suboptimum performances among the teams that treat patients with colorectal cancers. Studies involving more than 4000 patients show that large reductions in local recurrences and a 20% increase in survival can be achieved with high-quality surgical and pathological training in total mesorectal excision. New developments in radiology and oncology may further increase this benefit.