The appendix "mucocoele" misnomer: radiological terminology of "likely appendix mucinous neoplasm" better reflects pathology findings.

AIM: To review the radiological terminology used to describe dilated mucin-containing appendiceal lesions with correlation to the histopathological diagnosis. MATERIALS AND METHODS: Radiology and histopathology reports for all patients with an abnormally dilated appendix referred to a tertiary peritoneal malignancy centre, between January 2021 and December 2021, were reviewed. RESULTS: Overall, 213 patients were included with a median appendiceal diameter of 25.5 mm (range 10-125 mm). Peritoneal disease was present in 109 patients, with the remaining 104 cases demonstrating a dilated appendix only. Local radiology reports were available for 201 cases with the appendix described in 168 cases as appendiceal mucocoele (n=104), appendiceal neoplasm (n=40), appendicitis (n=18), and dilated appendix (n=6). The appendix was not mentioned in 33/201 (15%), either misinterpreted as other pathology (n=15) or not reported (n=18). Peritoneal malignancy histopathology reports were available in 188 cases and reported as low-grade appendix mucinous neoplasm (LAMN, n=144), high-grade appendix mucinous neoplasm (HAMN, n=13), LAMN with foci of HAMN (n=2), LAMN with neuroendocrine tumour (n=2), LAMN with goblet cell adenocarcinoma (n=1), goblet cell adenocarcinoma (n=8), mucinous adenocarcinoma (n=14), non-mucinous adenocarcinoma (n=1), and benign histology (n=3). Only one case of a true inflammatory "mucocoele"/retention cyst was reported. CONCLUSION: In this cohort of patients, the overwhelming majority of dilated, mucin-filled appendices contained malignant cells and benign mucin-filled appendices were rare. The present authors advocate that the term "likely appendix mucinous neoplasm" should replace "appendix mucocoele" to represent the most likely pathology and facilitate less ambiguous interpretation in management decisions.

Impact of ovarian metastases on survival in patients treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for peritoneal malignancy originating from appendiceal and colorectal cancer.

AIM: Ovarian metastases from gastrointestinal tract malignancies have been considered an ominous finding with poor prognosis. The aim of this project was to determine the impact on survival, and potential cure, when cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are combined to treat peritoneal malignancy in women with Krukenberg tumours. METHOD: A retrospective analysis of prospectively collected data between January 2010 and July 2015. Female patients undergoing complete CRS (macroscopic tumour removal) and HIPEC for pseudomyxoma peritonei (PMP) of appendiceal origin, or colorectal peritoneal metastases (CPM) were included. Survival was estimated using the Kaplan-Meier method and survival rates compared using the log-rank test. RESULTS: In total, 889 patients underwent surgery for peritoneal malignancy, of whom 551 were female. Of these, 504/551 (91%) underwent complete CRS and HIPEC. Overall, 405/504 (80%) had at least one involved ovary removed either during CRS and HIPEC or at their index prereferral operation. Three hundred and fifty-two patients (87%) had an appendiceal tumour and 53 (13%) had CPM. At a median follow up of 40 months, overall survival (OS) did not differ significantly between patients with or without ovarian involvement in women with a primary low-grade appendiceal tumour or CPM. In women with high-grade primary appendiceal pathology, OS was significantly lower in patients with ovarian metastases compared with those without ovarian involvement. CONCLUSION: Women with ovarian metastases from low-grade appendiceal tumours or colorectal cancer treated with CRS and HIPEC have similar survival rates to patients without ovarian metastases. Long-term survival and cure is feasible in patients amenable to complete tumour removal.

Variations in the management of significant polyps and early colorectal cancer: results from a multicentre observational study of 383 patients.

AIM: The concept of significant polyps and early colorectal cancer (SPECC) encompasses complex polyps not amenable to routine snare polypectomy or where malignancy cannot be excluded. Surgical resection (SR) offers definitive treatment, but is overtreatment for the majority which are benign and amenable to less invasive endoscopic resection (ER). The aim of this study was to investigate variations in the management and outcomes of significant colorectal polyps. METHOD: This was a retrospective observational study of significant colorectal polyps, defined as nonpedunculated lesions of ≥ 20 mm size, diagnosed across nine UK hospitals in 2014. Inclusion criteria were endoscopically or histologically benign polyps at biopsy. RESULTS: A total of 383 patients were treated by primary ER (87.2%) or SR (12.8%). Overall, 108/383 (28%) polyps were detected in the Bowel Cancer Screening Programme (BCSP). Primary SR was associated with a significantly longer length of stay and major complications (P < 0.01). Of the ER polyps, 290/334 (86.8%) patients were treated without undergoing surgery. The commonest indication for secondary surgery was unexpected polyp cancer, and of these cases 60% had no residual cancer in the specimen. Incidence of unexpected cancer was 10.7% (n = 41) and was similar between ER and SR groups (P = 0.11). On multivariate analysis, a polyp size of > 30 mm and non-BCSP status were independent risk factors for primary SR [OR 2.51 (95% CI 1.08-5.82), P = 0.03]. CONCLUSION: ER is safe and feasible for treating significant colorectal polyps. Robust accreditation within the BCSP has led to improvements in management, with lower rates of SR compared with non-BCSP patients. Standardization, training in polyp assessment and treatment within a multidisciplinary team may help to select appropriate treatment strategies and improve outcomes.

Cytoreductive surgery in combination with hyperthermic intraperitoneal chemotherapy improves survival in patients with colorectal peritoneal metastases compared with systemic chemotherapy alone.

BACKGROUND: Colorectal cancer peritoneal metastasis (CPM) confers an exceptionally poor prognosis, and traditional treatment involving systemic chemotherapy (SC) is largely ineffective. Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is increasingly advocated for selected patients with CPM; however, opinions are divided because of the perceived lack of evidence, high morbidity, mortality, and associated costs for this approach. As there is no clear consensus, the aim of this study was to compare outcomes following CRS+HIPEC vs SC alone for CPM using meta-analytical methodology, focusing on survival outcomes. Secondary outcomes assessed included morbidity, mortality, quality of life (QOL), and health economics (HE). METHODS: An electronic literature search was conducted to identify studies comparing survival following CRS+HIPEC vs SC for CPM. The odds ratio (OR) was calculated using the Mantel-Haenszel method with corresponding 95% confidence intervals (CI) and P-values. Heterogeneity was examined using the Q-statistic and quantified with I(2). The fixed-effect model (FEM) was used in the absence of significant heterogeneity. For included studies, 2- and 5-year survival was compared for CRS+HIPEC vs SC alone. RESULTS: Four studies (three case-control, one RCT) provided comparative survival data for patients undergoing CRS+HIPEC (n=187) vs SC (n=155) for CPM. Pooled analysis demonstrated superior 2-year (OR 2.78; 95% CI 1.72-4.51; P=0.001) and 5-year (OR 4.07; 95% CI 2.17-7.64; P=0.001) survival with CRS+HIPEC compared with SC. Mortality ranged from 0 to 8%. No data were available for the assessment of QOL or HE. CONCLUSIONS: Although limited by between-study heterogeneity, the data support the assertion that in carefully selected patients, multimodal treatment of CPM with CRS+HIPEC has a highly positive prognostic impact on medium- and long-term survival compared with SC alone. There is a paucity of comparative data available on morbidity, QOL, and HE.

Multicentre study of the learning curve and surgical performance of cytoreductive surgery with intraperitoneal chemotherapy for pseudomyxoma peritonei.

BACKGROUND: The learning curves for cytoreductive surgery with intraperitoneal chemotherapy for treatment of pseudomyxoma peritonei (PMP) were explored between international centres/surgeons to identify institutional or other factors that might affect performance. METHODS: Data from patients with PMP treated with the combined procedure across 33 international centres between 1993 and 2012 were analysed retrospectively. A risk-adjusted sequential probability ratio test was conducted after defining the target outcome as early oncological failure (disease progression within 2 years of treatment), an acceptable risk for the target outcome (odds ratio) of 2, and type I/II error rates of 5 per cent. The risk prediction model was elaborated and patients were evaluated sequentially for each centre/surgeon. The learning curve was considered to be overcome and proficiency achieved when the odds ratio for early oncological failure became smaller than 2. RESULTS: Rates of optimal cytoreduction, severe postoperative morbidity and early oncological failure were 84·4, 25·7 and 29·0 per cent respectively. The median annual centre volume was 17 (range 6-66) peritoneal malignancies. Only eight of the 33 centres and six of 47 surgeons achieved proficiency after a median of 100 (range 78-284) and 96 (86-284) procedures respectively. The most important institutional factor affecting surgical performance was centre volume. CONCLUSION: The learning curve is extremely long, so centralization and/or networking of centres is necessary to assure quality of services. One centre for every 10-15 million inhabitants would be ideal.

The English national low rectal cancer development programme: key messages and future perspectives.

AIM: Adenocarcinoma of the lower rectum is clinically challenging because of the need to choose between a wide excision to achieve oncological clearance, on the one hand, and sphincter conservation to maintain anal function, on the other. The English National Low Rectal Cancer Development Programme (LOREC) was developed under the auspices of the Association of Coloproctology of Great Britain and Ireland and the English National Cancer Action Team to improve the outcome of low rectal cancer in England. METHOD: LOREC was initiated focusing on preoperative imaging, selective neoadjuvant therapy, optimal surgical treatment and detailed pathological assessment of the excised specimen. Its key elements were 1-day multidisciplinary team (MDT) workshops, cadaveric surgical training, surgical mentoring, pathological audit and radiological workshops. RESULTS: Overall, 147 (89.6%) of 164 MDTs from 151 National Health Service (NHS) Trusts (some with two MDTs) in England participated in 15 workshops in Basingstoke or Leeds. In addition, 112 surgeons attended a 1-day cadaveric training programme in Bristol, Newcastle or Nottingham, with the main focus on extralevator abdominoperineal excision and pelvic reconstruction, with input from anatomists and from colorectal and plastic surgeons. CONCLUSION: Optimal staging, selective preoperative chemoradiotherapy and precise surgery were considered as crucial to improve the outcome for patients with low rectal cancer.

Development and evaluation of a cadaveric training curriculum for low rectal cancer surgery in the English LOREC National Development Programme.

AIM: The National Development Programme for Low Rectal Cancer in England (LOREC) was commissioned in response to wide variation in the outcome of patients with low rectal cancer. One of the aims of LOREC was to enhance surgical techniques in managing low rectal cancer. This study reports on the development and evaluation of a novel national technical skills cadaveric training curriculum in extralevator abdominoperineal excision. METHOD: Three sites were commissioned for the cadaveric workshops, each delivering the same training curriculum. Training was undertaken in pairs using a fresh-frozen cadaveric model under the supervision of expert mentors. Global assessment score (GAS) forms were developed to promote reflective learning. Feedback on the impact of the workshop was obtained from a sample of delegates at the end of the course, and also after 3-23 months via an online questionnaire. RESULTS: Overall 112 consultant colorectal surgeons attended one of 15 cadaveric technical skills training workshops. Seventy-six per cent of delegates reported easy identification of anatomy in the cadaveric model; 67% found tissue planes easy to interpret. Ninety-six per cent of delegates felt the workshop would influence their future practice; 96% reported increased awareness of important anatomy. Only 2% of delegates wished to pursue supplementary formal training from LOREC. CONCLUSION: Fresh-frozen cadavers could provide an effective training model for low rectal surgery. A structured 1-day cadaveric workshop has facilitated the dissemination of technical skills for management of low rectal cancer. Attending the cadaveric workshop enhanced delegates' confidence in performing this procedure.

Appendicitis to multivisceral transplantation: a career experience with appendiceal malignancy.

John Hunter is regarded as the father of scientific surgery. His principles involved reasoning, observation and experimentation. His most powerful saying was: "Why not try the experiment?" This manuscript charts a career in abdominal surgery ranging from the treatment of appendicitis to the development of the largest appendiceal tumour centre in the world. The journey has led to the first report of a successful multivisceral and abdominal wall transplant for patients with recurrent non-resectable pseudomyxoma peritonei. We all stand on the shoulders of giants and surgery progresses by learning from the past while being prepared to experiment into the future.

Extraperitoneal resection of the right colon for locally advanced colon cancer.

AIM: Optimal colon cancer surgery correlates with a reduction in recurrence rate and improved overall prognosis. This technical note describes the extraperitoneal approach for locally advanced right colon cancer. METHOD: The retroperitoneal technique, mainly used in pseudomyxoma peritonei resectional surgery, is described in three surgical steps and it is compared with existing surgical approaches for right colon cancer. RESULTS: This approach has the advantages of early entry in the retroperitoneal plane well away from the tumour, early recognition and protection of the ureter and minimal manipulation of the tumour-bearing right colon. CONCLUSION: Extraperitoneal resection of the right colon for locally advanced colon cancer is technically feasible, safe and achieves tumour-free retroperitoneal margins.

The use of cardiac output monitoring to guide the administration of intravenous fluid during hyperthermic intraperitoneal chemotherapy.

AIM: The optimal strategy for intravenous (IV) fluid management during administration of hyperthermic intraperitoneal chemotherapy (HIPEC) is unclear. In this prospective study we describe the use of a LiDCOrapid™ (LiDCO, Cambridge, UK) cardiac output monitor to guide IV fluid management during cytoreductive surgery (CRS) with HIPEC. The aim of this study was to determine whether cardiac output monitoring will allow close maintenance of physiological parameters during the HIPEC phase. METHOD: Twenty-five patients who underwent CRS combined with HIPEC were included in the study. Intra-operative IV fluid boluses were titrated using parameters measured by the LiDCOrapid™ monitor. Stroke volume variation was maintained below 10% with fluid boluses and mean arterial pressure was maintained within 20% of the baseline figure with vasopressors. RESULTS: There was no significant change in heart rate and cardiac output. The systemic vascular resistance dropped from an average of 966 dyn.s/cm-5 to 797 dyn s/cm(5) at 60 min during the HIPEC phase (P = 0.62) despite an increase in the dose of phenylepherine. The average total volume of fluid given was 748 ml in the first 30 min and 630 ml in the second 30 min with an average urine output of 307 and 445 ml, respectively. The change in lactate levels was not statistically or clinically significant. CONCLUSION: LiDCOrapid™ is an effective noninvasive tool for guiding fluid management in this population. It allows the anaesthesiologist to maintain tight control of essential physiological parameters during a phase of the procedure in which there is a risk of renal injury.

Importance of gender in diffuse malignant peritoneal mesothelioma.

BACKGROUND: Combined therapy involving cytoreductive surgery (CRS) and perioperative intraperitoneal chemotherapy has been shown to improve survival outcomes for patients with diffuse malignant peritoneal mesothelioma (DMPM). The present study aims to investigate gender as a potential prognostic factor on overall survival. PATIENTS AND METHODS: Over a period of two decades, 294 patients who underwent CRS and perioperative intraperitoneal chemotherapy were selected from a large multi-institutional registry to assess the prognostic significance of gender on overall survival. RESULTS: Female patients were shown to have a significantly improved survival outcome than male patients (P < 0.001). Staging according to a recently proposed tumor-node-metastasis categorization system was significant in both genders. Older female patients had significantly worse survival than younger female patients (P = 0.019), a finding that was absent in male patients. Female patients with low-stage disease were found to have a very favorable long-term outcome after combined treatment. CONCLUSIONS: Gender has demonstrated a significant impact on overall survival for patients with DMPM after CRS and perioperative intraperitoneal chemotherapy. An improved understanding of the role of estrogen in the pathogenesis of DMPM may improve the prognostication of patients and determine the role of adjuvant hormonal treatment in the future.

The majority of colorectal resections require an open approach, even in units with a special interest in laparoscopic surgery.

AIM: Proponents suggest that laparoscopic colorectal resection might be achievable in up to 90% of cases, while keeping conversion rates below 10%. This unselected prospective case series reports on the proportion of patients having a completed laparoscopic colorectal resection in two units where laparoscopic colorectal practice is well established and readily available. METHOD: All patients undergoing elective and emergency colorectal resection during a 6-month period were identified. The underlying pathology and the surgical approach (laparoscopic or open) were recorded. The contraindications to laparoscopic resection were also documented. The need and rationale for conversion to an open approach were recorded. RESULTS: In total, 205 consecutive patients (160 elective and 45 emergency procedures) underwent colorectal resection for malignancy [117 (57%) patients] and benign pathology [88 (43%) patients]. Laparoscopic resection was attempted in 127/205 (62%) patients and 31/127 (24%) of these were converted to open surgery. The main reasons for not attempting laparoscopic resection were locally advanced disease and emergency surgery. The commonest reasons for conversion were advanced disease and to allow completion of rectal dissection and/or cross-stapling of the rectum. CONCLUSION: Despite a special interest in laparoscopic colorectal surgery of the two colorectal units who provided the data for this study, fewer than half (96/205; 47%) of the patients in this consecutive unselected series who were undergoing major colorectal resection had the procedure completed laparoscopically.

A pictorial description of extralevator abdominoperineal excision for low rectal cancer.

AIM: Extralevator abdominoperineal excision in the prone position has been reported as a method to improve the poor outcome sometimes observed after abdominoperineal excision (APE) for low rectal cancer. In this paper a pictorial guide is presented describing the key anatomical steps and landmarks of the operation. METHOD: Intraoperative footage of five APE operations filmed in high definition was reviewed and key stages of the operation were identified. Still frames were captured from these sequences to illustrate this guide. An edited video sequence was produced from one of these operations to accompany this paper. CONCLUSION: The prone APE allows improved visualization of the perineal portion of the operation by the surgeon, assistants and observers. It permits clear demonstration for teaching. Prospective evaluation is still required to identify patients who would benefit from extralevator APE.