Rectal cancer: future directions and priorities for treatment, research and policy in New Zealand

New Zealand has one of the highest incidences of rectal cancer in the world, and its optimal management requires a multidisciplinary approach. A National Rectal Cancer Summit was convened in August 2013 to discuss management of rectal cancer in the New Zealand context, to highlight controversies and discuss domestic priorities for the future. This paper summarises the priorities for treatment, research and policy for rectal cancer services in New Zealand identified as part of the Summit in August. The following priorities were identified: - Access to high-quality information for service planning, review of outcomes, identification of inequities and gaps in provision, and quality improvement; - Engagement with the entire sector, including private providers; - Focus on equity; - Emerging technologies; - Harmonisation of best practice; - Importance of multidisciplinary team meetings. In conclusion, improvements in outcomes for patients with rectal cancer in New Zealand will require significant engagement between policy makers, providers, researchers, and patients in order to ensure equitable access to high quality treatment, and strategic incorporation of emerging technologies into clinical practice. A robust clinical information framework is required in order to facilitate monitoring of quality improvements and to ensure that equitable care is delivered.

A randomized, placebo-controlled, double-blind phase II trial of peri-operative cimetidine in early colorectal cancer

509

Background: A Cochrane meta-analysis of randomised trials using histamine-type 2 receptor antagonists with surgery for colorectal cancer (CRC) demonstrated a hazard ratio of 0.53 for mortality if patients used cimetidine. The benefit is likely to be specific to patients whose tumours express the antigens that allow circulating cells to bind to endothelial selectin (E-selectin), the expression of which is induced by inflammatory cytokines perioperatively and inhibited by cimetidine. This trial sought to evaluate several key issues critical to informing the conduct of a phase 3 trial. Methods: Patients with non-metastatic CRC planned for curative-intent surgery were randomised to receive cimetidine 800mg BID or placebo orally for 5 weeks, starting 2-7 days preoperatively. A subset of patients had serial blood sampling for inflammatory cytokines. In addition to DFS and OS, endpoints assessed include treatment compliance and toxicity, recruitment issues, post-operative stay and complications, and tumour characteristics including expression of sialyl Lewis antigens and COX-2. Results: 123 patients (36% female) have been recruited in 4 centres over 3.5 years; another 4 are required to complete the planned 120 treated patients. The primary tumour was rectal in 45% and pathological postoperative tumour stage was 0-I, II, III, and IV in 29%, 33%, 35%, and 2% respectively. About 50% of CRC patients were eligible and fewer than half of those were recruited. Patient compliance was excellent with 89% of patients taking their medication orally in the first 2 days postoperatively. Inflammatory cytokines were commonly elevated postoperatively for up to 2 weeks but normalised by 4 weeks. Immunostaining for tumour antigens is in progress and will be presented. DFS and OS data are immature. Conclusions: Oral administration of cimetidine for 5 weeks is well-tolerated and feasible over the perioperative period, and covers the duration of elevated inflammatory cytokines. Correlative immunostaining studies will be presented. Clinical trial information: 12609000769280.

Immunochemistry screening for Lynch syndrome in colorectal adenocarcinoma using an initial two antibody panel can replace a four antibody panel

AIM

The current practice in immunochemistry staining for Lynch syndrome (LS) is to use a four-antibody panel, (MLH1, MSH2, MSH6, PMS2) to screen for the four Mismatch Repair (MMR) gene expressions involved. We hypothesised that testing two antibodies (MSH6 and PMS2), followed by the other two only when there is loss of expression of the first two antibodies, would be equally effective as a four antibody panel in detecting LS. This hypothesis is based on the biochemical binding properties of the MMR proteins.

METHODS

We tested this hypothesis on a patient cohort consisting of all cases of colorectal cancer that were stained for MMR gene expression at Auckland City Hospital (Auckland, New Zealand) from the years 2000 to 2010 (inclusive), providing a series of 410 cases for this study. Exclusions were made based on heterogeneous staining pattern and unsatisfactory staining results on MSH6 and PMS2, which left n=400 included in the study.

RESULTS

The MMR gene protein stains were regarded as demonstrating loss of expression (LOE) when there was no uptake in the nucleus of the tumour cells, with a positive internal control. The results from our analysis supported our hypothesis. Seventy-four cases showed LOE of MSH6 or PMS2. One of them showed LOE of all four MMR proteins. For the remaining 326 cases, there was no LOE of all four MMR proteins.

CONCLUSION

Our study gives further evidence that an initial two-antibody panel consisting of PMS2 and MSH6 would be as effective as a four-antibody panel in detecting DNA MMR gene protein LOE. This study has implications for significant cost cutting and improved efficiency in detection of DNA MMR gene protein LOE in LS.

Pathological reporting of malignant colorectal polyps

AIM

The pathological reporting of malignant colorectal polyps plays an important role in determining whether definitive surgical resection is required following endoscopic polypectomy. This study aims to assess the adequacy of reporting on malignant polyp specimens at Auckland Hospital and whether synoptic reporting results in an improvement.

METHOD

The pathology database at Auckland Hospital was accessed using a search strategy to identify all malignant polyps diagnosed between 1999 and 2011. Pathology reports were reviewed retrospectively.

RESULTS

In total 121 malignant polyps were found. Of these, 73 were colonoscopic polypectomies, 41 were colectomy specimens, and seven transanal resections. Of the 41 colectomy specimens, 19 (46%) were reported in synoptic format compared with none of the colonoscopic polypectomies or transanal resections. The status of the margin of excision, differentiation, and presence of lymphovascular invasion were given in 100% of synoptic reports compared with 51% of non-synoptic reports.

CONCLUSION

Synoptic reporting does improve the completeness of pathological reporting in malignant colorectal polyps. Currently none of the colonoscopically excised malignant polyps are reported in this format at Auckland Hospital. The development and routine use of a synoptic system for reporting on malignant polyps would give clinicians more information on which to base decisions.

Defining postoperative ileus: results of a systematic review and global survey

BACKGROUND

There is a lack of an internationally accepted standardised clinical definition for postoperative ileus (POI). This has made it difficult to estimate incidence and identify risk factors and has compromised external validity of clinical trials.

AIM

To clarify terminology of POI and propose concise, clinically quantifiable definitions.

METHODS

A systematic review extracted definitions from randomised trials published between 1996 and 2011 investigating POI after abdominal surgery. This was followed by a global survey seeking opinions of those who have published in the field.

RESULTS

Definitions were extracted from 52 identified trials. Responses were received in the survey from 45 of 118 corresponding authors. Data were amalgamated to synthesise the following definitions: postoperative ileus (POI) "interval from surgery until passage of flatus/stool AND tolerance of an oral diet"; prolonged POI "two or more of nausea/vomiting, inability to tolerate oral diet over 24 h, absence of flatus over 24 h, distension, radiologic confirmation occurring on or after day 4 postoperatively without prior resolution of POI"; recurrent POI "two or more of nausea/vomiting, inability to tolerate oral diet over 24 h, absence of flatus over 24 h, distension, radiologic confirmation, occurring after apparent resolution of POI". Concordance of the latter two definitions with survey responses were ≥75 %.

CONCLUSION

We have proposed standardised endpoints for use in future studies to facilitate objective comparison of competing interventions.

Management of prolonged post-operative ileus: evidence-based recommendations

BACKGROUND

Prolonged post-operative ileus (PPOI) occurs in up to 25% of patients following major elective abdominal surgery. It is associated with a higher risk of developing post-operative complications, prolongs hospital stay and confers a significant financial load on health-care institutions. Literature outlining best-practice management strategies for PPOI is nebulous. The aim of this text was to review the literature and provide concise evidence-based recommendations for its management.

METHODS

A literature search through the Ovid MEDLINE, EMBASE, Google Scholar and Cochrane databases was performed from inception to July 2012 using a combination of keywords and MeSH terms. Review of the literature was followed by synthesis of concise recommendations for management accompanied by Strength of Recommendation Taxonomy (either A, B or C).

RESULTS

Recommendations for management include regular evaluation and correction of electrolytes (B); review of analgesic prescription with weaning of narcotics and substitution with regular paracetamol, regular non-steroidal anti-inflammatory drugs if not contraindicated, and regular or as-required Tramadol (A); nasogastric decompression for those with nausea or vomiting as prominent features (C); isotonic dextrose-saline crystalloid maintenance fluids administered within a restrictive regimen (B); balanced isotonic crystalloid replacement fluids containing supplemental potassium, in equivalent volume to losses (C); regular ambulation (C); parenteral nutrition if unable to tolerate an adequate oral intake for more than 7 days post-operatively (A) and exclusion of precipitating pathology or alternate diagnoses if clinically suspected (C).

CONCLUSIONS

Recommendations have a variable and frequently inconsistent evidence base. Further research is required to validate many of the outlined recommendations and to investigate novel interventions that may be used to shorten duration of PPOI.

Validation of the Phase II Feasibility Study in a Palliative Care Setting

Background:

Malignant bowel obstruction (MBO) is common in patients with advanced cancer.

Aim:

To perform a phase II study to assess the feasibility of conducting a phase III trial investigating the therapeutic value of gastrografin in MBO.

Methods:

Randomized double-blinded placebo-controlled feasibility study. Participants received 100 mL of either gastrografin or placebo.

Results:

Over 8 months, 57 patients were screened and 9 enrolled (15.8% recruitment rate). Of the 9 enrolled, 4 received gastrografin (with 2 completing assessment) and 5 received placebo (with 4 completing assessment).

Conclusions:

It is not feasible to conduct a phase III trial using the same study protocol. This study validates the use of the phase II feasibility study to assess protocol viability in a palliative population prior to embarking on a larger trial.

Early ileostomy closure: is there a downside?

BACKGROUND

A loop ileostomy is a common adjunct to formation of a low colorectal anastomosis. However, it is not without significant physical and psychological morbidity, and financial cost. Feasibility of early closure during the index admission has previously been reported. This pilot study examines the safety of early closure compared with traditional timing.

METHODS

A retrospective audit of consecutive ileostomy closures performed in a tertiary colorectal unit from January 2008 to January 2010. Demographic data, treatment data and complications were collected by a single investigator from a prospective clinical audit database and hospital records. Patients undergoing early closure (within 10 days of the index operation) were compared with the traditional timing group.

RESULTS

A total of 93 patients underwent closure of loop ileostomy during the study period (44 female; 49 male). Median patient age was 61 years. Nineteen patients (20%) underwent early closure. There were six wound infections in the early closure group (32%), and five in the traditional timing group (7%) (P = 0.01). There was no significant difference in other complications between the two groups. There was a significantly shorter overall hospital stay in the early closure group with a median stay of 14 days (range 10-26), and in the traditional timing group a median stay of 17 days (range 7-80) (P = 0.05). Seven patients (9%) in the traditional timing group had ileostomy-related complications.

CONCLUSION

Early ileostomy closure appears to be associated with an increased wound infection rate but otherwise appears to be a safe alternative to traditional closure in selected patients and may reduce overall hospital stay.

Prospects for population colorectal cancer screening in New Zealand

AIM

In 2005 the National Screening Unit of the Ministry of Health appointed a Colorectal Screening Advisory Group to provide independent strategic advice and recommendations on population screening for colorectal cancer (CRC) in New Zealand.

METHOD

Evidence-based review of relevant literature and assessment of CRC screening using the New Zealand Criteria to Assess Screening Programmes.

RESULTS

Guaiac faecal occult blood test (FOBTg), immunochemical FOBT (FOBTi), flexible sigmoidoscopy, colonoscopy, and CT colonography were considered. FOBTg is the only test supported by high quality evidence from randomised controlled trials but has limited sensitivity and achieves modest CRC mortality reduction over time. FOBTi has higher analytical sensitivity than FOBTg and would be assumed to achieve greater mortality reduction. A CRC screening programme requires substantial planning and resources. Currently public hospitals cannot deliver timely diagnostic or surveillance colonoscopy.

CONCLUSION

The Advisory Group recommends that a feasibility study of CRC screening using FOBTi be undertaken. This would help determine the performance of the FOBTi in the New Zealand population and whether the New Zealand health system could support an acceptable, effective and economically efficient CRC screening programme. To optimise the diagnosis and treatment of colorectal cancer there is an immediate need to expand colonoscopy services and to ensure that throughout New Zealand the treatment outcomes for CRC, both surgical and oncological, meet international standards.

Rectal duplication cyst presenting as perianal sepsis: report of two cases and review of the literature

INTRODUCTION

Recurrent perianal sepsis is a difficult problem to manage in colorectal surgical practice. One cause is rectal duplication cyst, a rare congenital lesion that is easily overlooked. Many cases have associated congenital defects, especially musculoskeletal anomalies, and may provide a clue to the underlying condition. Early diagnosis is important because these cysts do not resolve spontaneously and may undergo malignant change.

METHODS

We present two cases of middle-aged females who presented with perianal sepsis secondary to rectal duplication cyst. The first case had numerous surgical procedures for a perianal fistula during a ten-year period. She had associated sacral anomalies consistent with Currarino syndrome. The second case presented with a perineal mass after a bout of perianal inflammation. Both cases had the entire cyst surgically excised.

RESULTS

There were no complications postoperatively and no recurrence at follow-up. Histopathology revealed no malignancy in the cyst.

CONCLUSIONS

Rectal duplication cyst is a rare cause of recurrent perianal sepsis that should be considered in difficult cases, especially in those with associated musculoskeletal anomalies. Complete surgical excision is the preferred treatment to prevent recurrence and the risk of malignant degeneration.