Outcomes Following Immediate Vertical Rectus Abdominis Myocutaneous (VRAM) Flap-Based Perineal Reconstruction Following Resectional Surgery For Pelvic Malignancies.

BACKGROUND: Increasingly radical surgery combined with neo-adjuvant radiotherapy present a challenge for the reconstructive surgeon. The study objective was to review outcomes of Vertical Rectus Abdominis Myocutaneous (VRAM) flap-based perineal reconstruction following resectional surgery for pelvic malignancies. METHODS: Single-centre retrospective analysis of patients undergoing immediate VRAM flap reconstruction of a perineal/pelvic defect for pelvic malignancy between July 2009 and November 2017. Primary outcome was perineal morbidity (surgical site infection (SSI), flap loss or dehiscence and perineal hernia). Secondary outcomes were length of stay and donor site morbidity (SSI, full-thickness dehiscence and incisional hernia). RESULTS: A total of 178 patients (96 females) were included. Median age was 67 years (range 28-88). The majority were performed for locally advanced rectal adenocarcinoma (n = 122; 68.5%) and 136 (76.4%) patients had received neoadjuvant radiotherapy. Four patients had complete flap loss (2.3%), and 40 had perineal dehiscence (22.5%); however, only, 18 patients required a return to theatre during the admission for perineal-related complications (10.1%). Abdominal dehiscence occurred in six patients (3.4%). Median length of post-operative stay was 15 days (6-131). Sixty-day mortality rate was 1.1%. SSI at the midline and perineum occurred in 34 (19.1%) and 38 patients (21.3%), respectively. At 90-day post-operatively, 75.6% of perineal wounds were healed. During a median follow-up of 44.5 months, twelve, eleven and 39 patients were diagnosed with perineal, midline and parastomal hernias, respectively (6.9%, 6.2% and 21.9%). CONCLUSIONS: It is important to have accurate knowledge of perineal and donor-site morbidity rates to allow an informed consent process.

DNA hypermethylation as a predictor of extramural vascular invasion (EMVI) in rectal cancer.

PURPOSE: DNA hypermethylation in gene promoter regions (CpG islands) is emerging as an important pathway in colorectal cancer tumourigenesis. Whilst genetic mutations have been associated with extramural vascular invasion (EMVI) in rectal cancer, no such association has yet been made with epigenetic factors. METHODS: 100 consecutive neoadjuvant-naïve patients undergoing curative surgery for rectal were classified according to the presence or absence of EMVI on histopathological examination. DNA was extracted from tumours and subjected to bisulfite conversion and methylation-specific PCR to determine CIMP status (high, intermediate, or low; according to a validated panel of 8 genes). CIMP status was correlated with EMVI status, histopathological, clinical, and demographic variables, in addition to overall (OS) and disease free (DFS) survival. RESULTS: 51 patients were characterised as CIMP-low, 48 CIMP-intermediate, and one patient CIMP-high. EMVI-positivity was associated with CIMP-intermediate epigenotype (p < 0.001). Patients with EMVI-positive tumours were found to have significantly more advanced disease by pT, pN, and pAJCC categorisation (p = 0.002, p < 0.001, and = p < 0.001, respectively). EMVI-positivity was significantly associated with the requirement for adjuvant chemotherapy (p < 0.001), and worse DFS but not OS (p = 0.012 and p = 0.052). CONCLUSIONS: Given the association between CIMP-intermediate epigenotype and EMVI-positivity, and the subsequent disadvantage in pathological stage, requirement for adjuvant therapy and worse survival, tumour epigenotyping could potentially play an important role in personalising patients' cancer care. Further work is required to understand the mechanisms that underlie the observed effect, with the hope that they may provide novel opportunities for intervention and inform treatment decisions in rectal cancer.

Extramural vascular invasion and response to neoadjuvant chemoradiotherapy in rectal cancer: Influence of the CpG island methylator phenotype.

AIM: To identify whether CpG island methylator phenotype (CIMP) is predictive of response to neoadjuvant chemoradiotherapy (NACRT) and outcomes in rectal cancer. METHODS: Patients undergoing NACRT and surgical resection for rectal cancer in a tertiary referral centre between 2002-2011 were identified. Pre-treatment tumour biopsies were analysed for CIMP status (high, intermediate or low) using methylation specific PCR. KRAS and BRAF status were also determined using pyrosequencing analysis. Clinical information was extracted from case records and cancer services databases. Response to radiotherapy was measured by tumour regression scores determined upon histological examination of the resected specimen. The relationship between these molecular features, response to NACRT and oncological outcomes were analysed. RESULTS: There were 160 patients analysed with a median follow-up time of 46.4 mo. Twenty-one (13%) patients demonstrated high levels of CIMP methylation (CIMP-H) and this was significantly associated with increased risk of extramural vascular invasion (EMVI) compared with CIMP-L [8/21 (38%) vs 15/99 (15%), P = 0.028]. CIMP status was not related to tumour regression after radiotherapy or survival, however EMVI was significantly associated with adverse survival (P < 0.001). Intermediate CIMP status was significantly associated with KRAS mutation (P = 0.01). There were 14 (9%) patients with a pathological complete response (pCR) compared to 116 (73%) patients having no or minimal regression after neoadjuvant chemoradiotherapy. Those patients with pCR had median survival of 106 mo compared to 65.8 mo with minimal regression, although this was not statistically significant (P = 0.26). Binary logistic regression analysis of the relationship between EMVI and other prognostic features revealed, EMVI positivity was associated with poor overall survival, advanced "T" stage and CIMP-H but not nodal status, age, sex, KRAS mutation status and presence of local or systemic recurrence. CONCLUSION: We report a novel association of pre-treatment characterisation of CIMP-H with EMVI status which has prognostic implications and is not readily detectable on pre-treatment histological examination.

Genetic and Epigenetic Intra-tumour Heterogeneity in Colorectal Cancer.

INTRODUCTION: Colorectal cancer (CRC) is a highly heterogeneous disease, with pathologically similar cancers having completely different responses to treatment and patient survival. Intra-tumour heterogeneity (defined as distinct morphological and phenotypic differences) has recently been demonstrated to be an important factor in the development and behaviour of cancer cells and can be used to determine response to anticancer therapy. METHOD: Patients with resected CRC had DNA extracted from eight defined tumour areas which were analysed for two genetic mutations (BRAF and KRAS) and one epigenetic trait (CpG island methylator phenotype/CIMP). Normal adjacent tissue was studied as control. RESULTS: Twelve patients with CRC were included. Intra-tumoural heterogeneity for KRAS mutation was seen in 2 patients (17%). There was no statistical evidence of CIMP status heterogeneity (p = 0.85), but 6 of the 12 patients (50%) demonstrated at least one heterogeneous area within the tumour. DISCUSSION: Intra-tumoural heterogeneity for both genetic and epigenetic factors in CRC is more prevalent than previously thought in Stage II and Stage III CRC. This study provides new insight into epigenetic heterogeneity of CRC and supports the development of a more targeted biopsy strategy to support expansion of personalised treatment.

Protocol for a multicentre randomised feasibility trial evaluating early Surgery Alone In LOw Rectal cancer (SAILOR).

INTRODUCTION: There are 11 500 rectal cancers diagnosed annually in the UK. Although surgery remains the primary treatment, there is evidence that preoperative radiotherapy (RT) improves local recurrence rates. High-quality surgery in rectal cancer is equally important in minimising local recurrence. Advances in MRI-guided prediction of resection margin status and improvements in abdominoperineal excision of the rectum (APER) technique supports a reassessment of the contribution of preoperative RT. A more selective approach to RT may be appropriate given the associated toxicity. METHODS AND ANALYSIS: This trial will explore the feasibility of a definitive trial evaluating the omission of RT in resectable low rectal cancer requiring APER. It will test the feasibility of randomising patients to (1) standard care (neoadjuvant long course RT±chemotherapy and APER, or (2) APER surgery alone for cT2/T3ab N0/1 low rectal cancer with clear predicted resection margins on MRI. RT schedule will be 45 Gy over 5 weeks as current standard, with restaging and surgery after 8-12 weeks. Recruitment will be for 24 months with a minimum 12-month follow-up. OBJECTIVES: Objectives include testing the ability to recruit, consent and retain patients, to quantify the number of patients eligible for a definitive trial and to test feasibility of outcomes measures. These include locoregional recurrence rates, distance to circumferential resection margin, toxicity and surgical complications including perineal wound healing, quality of life and economic analysis. The quality of MRI staging, RT delivery and surgical specimen quality will be closely monitored. ETHICS AND DISSEMINATION: The trial is approved by the Regional Ethics Committee and Health Research Authority (HRA) or equivalent. Written informed consent will be obtained. Serious adverse events will be reported to Swansea Trials Unit (STU), the ethics committee and trial sites. Trial results will be submitted for peer review publication and to trial participants. TRIAL REGISTRATION NUMBER: ISRCTN02406823.

Review of the development of DNA methylation as a marker of response to neoadjuvant therapy and outcomes in rectal cancer.

There is much debate around the preoperative treatment of colorectal cancer and, in particular, neoadjuvant chemoradiotherapy in locally advanced rectal cancer. This treatment carries a significant risk of harmful side effects and has a highly variable response rate. Predictive biomarkers have been the subject of a great deal of study with the aim of pretreatment risk stratification in order to more accurately determine which patients will derive the most benefit and least harm from these treatments. The study of epigenetics in colorectal cancer is relatively recent, and distinct patterns of aberrant DNA methylation, in particular the cytosine-phosphate-guanine (CpG) island methylator phenotype (CIMP), have been demonstrated in colorectal cancer, and their characterisation and significance are under debate, particularly in rectal cancer. These patterns of DNA methylation have been associated with differences in response to therapy and treatment outcomes and therefore have the potential to be used as biomarkers in tailored therapy regimes for patients with rectal cancer. This review aims to summarise the current state of the art in rectal cancer, with particular regard to the determination of DNA methylation patterns, the CpG island methylator phenotype and its potential as a novel biomarker in rectal cancer treatment and prediction of outcomes and response after neoadjuvant chemoradiotherapy.

Clinicopathological characteristics of colorectal cancer presenting under the age of 50.

OBJECTIVE: Previous studies suggest that colorectal cancer (CRC) presenting at a young age tends to be advanced, proximally located and associated with a poor outcome. The aim of this study was to analyse characteristics of CRC in a cohort under the age of 50. METHOD: A single centre retrospective cohort study of consecutive patients under the age of 50 receiving potentially curative resection was performed. Clinical and pathological data was collected from a prospectively maintained cancer registry database. Of 2799 patients having CRC resections between 2002 and 2013, 103 patients (3.6%) were under 50, with full survival data available on 98 (3.5%). An additional 7 patients under 50 had inoperable disease. The proportion of patients under 50 was constant throughout the study period. A group of 98 consecutive patients over the age of 50 undergoing surgery for colorectal cancer in the same centre was used for comparison. Just 7 patients (7%) had pathologically verified FAP or Lynch syndrome, although there was a high suspicion of Lynch syndrome in further 3 patients. CONCLUSION: There was a higher proportion of rectal cancer in the under 50s (p < 0.0001), although there was no significant difference in the staging of the disease or lymph node positivity. There was a greater incidence of poor differentiation in the younger patients, but there was no effect on 5-year overall survival (71.4%) which is much higher than in the reported literature. The majority of colorectal cancers presenting under the age of 50 were sporadic, and a higher proportion of rectal cancer was observed compared with the older patients, and as compared to the published literature on younger CRC patients. This paper adds to the literature by demonstrating that despite advanced stage at presentation of colorectal cancer requiring extended surgery and multimodal treatment, this young age group experienced good overall survival.

Long term outcomes after lateral anal sphincterotomy for anal fissure: a retrospective cohort study.

PURPOSE: Lateral anal sphincterotomy is the gold standard of surgical treatment for anal fissure. Patients undergoing this procedure are warned about the risk of incontinence; however, there are few reports on long-term outcomes. We conducted this study to investigate long-term outcomes after lateral anal sphincterotomy, focusing specifically on postoperative incontinence. METHODS: Patients who underwent lateral anal sphincterotomy at a university teaching hospital between 1998 and 2004 were sent questionnaires to allow us to assess their continence according to the Cleveland Continence Score. RESULTS: The response rate was 58 % and the responders comprised 25 men and 13 women, with a median age of 49 years (range 16-82 years). The success rate for fissure healing following surgery was 92 %, being significantly more likely in patients with textbook symptoms (p = 0.016) and those with chronic disease (p = 0.006). The overall complication rate was 13.2 %. Long-term objective and symptomatic incontinence were reported by two (5.6 %) patients, one of whom required a colostomy. CONCLUSION: Success rates after lateral anal sphincterotomy were satisfactory, but careful patient selection based on symptoms and disease chronicity may improve results further. Patients with predisposing risk factors for the development of incontinence, particularly multiparous women, are arguably better treated with non-surgical options.

Strategies to improve clinical research in surgery through international collaboration.

More than 235 million patients undergo surgery every year worldwide, but less than 1% are enrolled in surgical clinical trials--few of which are international collaborations. Several levels of action are needed to improve this situation. International research collaborations in surgery between developed and developing countries could encourage capacity building and quality improvement, and mutually enhance care for patients with surgical disorders. Low-income and middle-income countries increasingly report much the same range of surgical diseases as do high-income countries (eg, cancer, cardiovascular disease, and the surgical sequelae of metabolic syndrome); collaboration is therefore of mutual interest. Large multinational trials that cross cultures and levels of socioeconomic development might have faster results and wider applicability than do single-country trials. Surgeons educated in research methods, and aided by research networks and trial centres, are needed to foster these international collaborations. Barriers to collaboration could be overcome by adoption of global strategies for regulation, health insurance, ethical approval, and indemnity coverage for doctors.

The management of primary small bowel and colon lymphoma--a review.

AIMS: The management of primary small bowel and colon lymphoma is controversial. A review of the literature was therefore undertaken to evaluate the evidence for the classification, staging, diagnosis, and treatment of primary small bowel and colon lymphoma and guide management. METHODS: A literature search was performed utilising Embase, Medline, and Pubmed and papers were evaluated on an individual basis. RESULTS: Consensus opinion favours the WHO classification scheme and the TNM staging systems for primary small bowel and colon lymphoma. CT enteroclysis and barium enterolysis are recommended for the diagnosis of primary small bowel lymphoma and capsule endoscopy and double-balloon enteroscopy maybe useful diagnostic tools. In terms of the diagnosis and staging of primary colonic lymphoma, the evidence is scarce and CT is to be recommended. The mainstay of treatment for primary GI lymphoma is surgery and/or chemotherapy. For primary small bowel and colonic lymphoma, there was no definitive evidence regarding the benefits of either strategy; however, chemotherapy seemed to give a survival benefit over surgery alone for primary small bowel lymphoma and colonic lymphoma was skewed towards surgery plus chemotherapy due to the large number of patients presenting as an emergency. CONCLUSION: Published data regarding the management of primary small bowel and colon lymphoma is very limited. Classification and staging should be standardised to enable accurate evaluation of investigations and treatments and a large RCT undertaken to compare chemotherapy and surgery. Currently, we would recommend that management should involve chemotherapy with surgery reserved for those with clinical indication.

Selection criteria for the radical treatment of locally advanced rectal cancer.

There are over 14,000 newly diagnosed rectal cancers per year in the United Kingdom of which between 50 and 64 percent are locally advanced (T(3)/T(4)) at presentation. Pelvic exenterative surgery was first described by Brunschwig in 1948 for advanced cervical cancer, but early series reported high morbidity and mortality. This approach was later applied to advanced primary rectal carcinomas with contemporary series reporting 5-year survival rates between 32 and 66 percent and to recurrent rectal carcinoma with survival rates of 22-42%. The Swansea Pelvic Oncology Group was established in 1999 and is involved in the assessment and management of advanced pelvic malignancies referred both regionally and UK wide. This paper will set out the selection, assessment, preparation, surgery, and outcomes from pelvic exenterative surgery for locally advanced primary rectal carcinomas.

The APC Variant p.Glu1317Gln predisposes to colorectal adenomas by a novel mechanism of relaxing the target for tumorigenic somatic APC mutations.

Multiple rare nonsynonymous variants in APC predispose to colorectal adenomas. The mechanisms through which such variants act have been unclear, but it has been proposed that a specific ("just-right") level of beta-catenin signaling is required for colorectal tumorigenesis. This appears to be mediated by selection for APC genotypes that retain one, or rarely two, 20 amino acid beta-catenin downregulating repeats (20AARs). We investigated the mechanism through which the variant p.Glu1317Gln (c.3949G>C) contributes to colorectal tumorigenesis. We compared the patterns of somatic APC mutations in tumors from patients with attenuated familial adenomatous polyposis (AFAP) who did, or did not, coinherit p.Glu1317Gln with their AFAP-causing APC mutations. Only 8.2% (4/49) of tumors carrying p.Glu1317Gln had somatic mutations predicted to result in mutant polypeptides retaining a single 20AAR, compared to 62.1% (36/58) of those which did not carry this variant (P=5.64 x 10(-9)). Furthermore, tumors with p.Glu1317Gln often carried somatic mutations that were unusually early or late (downstream of the second 20AAR) in the APC open reading frame. These data support a novel mechanism in which p.Glu1317Gln in combination with other weak mutant APC alleles (generating polypepetides with zero, two, or three 20AARs) can provide the necessary growth advantage for colorectal tumorigenesis.

The clinical significance of lymph node micrometastasis in stage I and stage II colorectal cancer.

AIM: Recent advances in immunohistochemical techniques have made it possible to identify micrometastasis using antibodies to cytokeratins (CK). The aim of the study was to determine the prevalence and prognostic significance of immunohistochemically detected micrometastasis (IHM) in patients with localised colorectal cancer (CRC) (Dukes' A and B). A further aim was to study the prognostic role of histopathological factors such as vascular invasion. METHODS: The original histology of 168 consecutive patients with Dukes' A or B tumours who had undergone curative resection was reviewed. Immunohistochemical staining was performed using CK antibodies, AE1/AE3 and MNF116 on all (n=898) lymph nodes. Survival analysis was performed on 105 cases that had been followed up until death or for at least 5 years. RESULTS: IHM were detected in 17.3% of lymph nodes analysed. Adverse outcome (death/local recurrence) was recorded in 8/49 (16%) patients with IHD-positive nodes and in 10/56 (18%) patients negative for IHM. IHM was not associated with adverse outcome on either univariate (p=0.540) or multivariate analyses (p=0.673). There was no correlation of IHM with age, gender, site, size and grade of tumour, depth of tumour invasion or perineural and vascular invasion. Vascular invasion was the only independent prognostic factor identified. DISCUSSION: We have shown that isolated CK-positive epithelioid cells are commonly found in morphologically benign pericolic lymph nodes of patients with localised (Dukes' A or B) CRC. These cells may represent occult micrometastasis but are not clinically significant. Vascular invasion identifies patients with localised CRC likely to develop recurrences or die of disease.

Reprimo 824 G>C and p53R2 4696 C>G single nucleotide polymorphisms and colorectal cancer: a case-control disease association study.

BACKGROUND: Improved survival from colorectal cancer (CRC) may result from screening for inherited genetic risk factors. Reprimo and p53R2 are p53-inducible genes involved in cell cycle surveillance and DNA repair. Single nucleotide polymorphisms (SNPs) of these genes have been discovered, but their effects on the genes' function and association with CRC is not known. METHODS: Ninety healthy controls, 52 diverticular disease controls and 96 CRC cases were genotyped. DNA was extracted from buccal brush biopsies. Genotyping was performed by polymerase chain reaction (PCR) or polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP) methods. Tests for Hardy-Weinberg equilibrium and allelic- and genotype-disease association were performed online using the Finetti program. RESULTS: All three populations were in Hardy-Weinberg equilibrium with respect to p53R2 4696C>G SNP, and no CRC associations were demonstrated with this SNP. The healthy and CRC populations were in Hardy-Weinberg equilibrium with respect to the Reprimo 824G>C SNP, but the diverticular disease population was not (P=0.03). No CRC were demonstrated with Reprimo 824G>C. CONCLUSION: No association between p53R2 4696C>G and Reprimo 824G>C with CRC was shown by this study. An association between the Reprimo 824G>C heterozygote and diverticular disease may exist on the basis of deviation from Hardy-Weinberg equilibrium.