Hartmann's procedure versus intersphincteric abdominoperineal excision (HiP Study): a multicentre prospective cohort study.

AIM: In patients with low rectal cancer it is occasionally necessary to avoid a low coloanal anastomosis due to patient frailty or poor function. In such situations there are two alternative approaches: Hartmann's procedure (HP) or intersphincteric abdominoperineal excision (IAPE). There are few data to guide surgeons as to which of these two procedures is the safest. The aim of this study was to determine the surgical complication rates associated with each procedure. METHOD: This was a multicentre, nonrandomized prospective cohort study of patients undergoing either HP or IAPE. The primary objective was to determine surgical complication rates. Secondary objectives included length of stay, time to adjuvant therapy and quality of life at 90 days. RESULTS: One hundred and seventy nine patients were recruited between April 2016 and June 2019; approximately two thirds of patients underwent HP and one third IAPE. The overall complication rate was high in both groups (54% for the HP group and 52% for the IAPE group). Surgery-specific complication rates were also high, but not significantly different: 43% for HP and 48% for IAPE. The pelvic abscess rate in HP was 11% and was significantly higher in patients with a palpable staple line (15% vs 2%). There was a higher incidence of serious medical complications following IAPE (16% vs 5%), along with a reduction in 90-day quality of life scores. CONCLUSION: This is the largest prospective study to compare HP and IAPE in patients undergoing rectal cancer surgery where primary anastomosis is not deemed appropriate. With similar complication rates, these data support the ongoing use of either HP or IAPE in this patient group.

Appendiceal tumours and pseudomyxoma peritonei: Literature review with PSOGI/EURACAN clinical practice guidelines for diagnosis and treatment

Pseudomyxoma Peritonei (PMP) is a rare peritoneal malignancy, most commonly originating from a perforated epithelial tumour of the appendix. Given its rarity, randomized controlled trials on treatment strategies are lacking, nor likely to be performed in the foreseeable future. However, many questions regarding the management of appendiceal tumours, especially when accompanied by PMP, remain unanswered. This consensus statement was initiated by members of the Peritoneal Surface Oncology Group International (PSOGI) Executive Committee as part of a global advisory role in the management of uncommon peritoneal malignancies. The manuscript concerns an overview and analysis of the literature on mucinous appendiceal tumours with, or without, PMP. Recommendations are provided based on three Delphi voting rounds with GRADE-based questions amongst a panel of 80 worldwide PMP experts.

Not all abdominal masses after colorectal cancer surgery are malignant: intra-abdominal fibromatosis masquerading as recurrence.

AIM: Intra-abdominal fibromatosis is an unusual mesenchymal tumour that can be locally aggressive without any metastatic potential. Fibromatosis may simulate cancer recurrence on imaging surveillance for colorectal cancer follow-up. The optimal treatment of recurrent peritoneal malignancy is cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Confirmatory biopsy of lesions suspicious for colorectal cancer recurrence may not be feasible, thereby rendering surgery the safest option. Our aim was to determine the incidence of fibromatosis in a cohort of patients undergoing CRS and HIPEC for suspected colorectal cancer recurrence. METHODS: One hundred and seventy-one CRS and HIPEC cases were performed at our Peritoneal Malignancy Institute between February 2007 and October 2018 for colorectal peritoneal metastases and were included in a prospectively maintained database. RESULTS: A total of 49 (29%) of 171 cases were performed for primary colorectal cancer with peritoneal metastases, whereas 122 (71%) of 171 cases were performed for suspected colorectal cancer recurrence detected on surveillance imaging after primary colorectal cancer resection. On histological analysis of the resected specimen, five (4.1%) of 122 cases undergoing CRS and HIPEC for colorectal recurrence had fibromatosis. CONCLUSION: Fibromatosis can masquerade as colorectal cancer recurrence. In this series it occurred with an incidence of 4.1% among a cohort of patients undergoing CRS and HIPEC for probable recurrence. Surgical resection may be the only option to confirm the diagnosis and rule out malignancy.

The current practice of cytoreductive surgery and HIPEC for colorectal peritoneal metastases: Results of a worldwide web-based survey of the Peritoneal Surface Oncology Group International (PSOGI).

BACKGROUND: At present, selected patients with resectable colorectal peritoneal metastases (CRC-PM) are increasingly treated with a combination therapy of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). The aim of this study was to investigate the current worldwide practice. METHODS: HIPEC experts from 19 countries were invited through the Peritoneal Surface Oncology Group International (PSOGI) to complete an online survey concerning their personal expertise and current hospital and countrywide practice. RESULTS: It is estimated that currently more than 3800 patients with CRC-PM (synchronous and metachronous) are annually treated with CRS and HIPEC in 430 centers. Integration of CRS and HIPEC in national guidelines varies, resulting in large treatment disparities between countries. Amongst the experts, there was general agreement on issues related to indication, surgical technique and follow up but less on systemic chemotherapy or proactive strategies. CONCLUSION: This international survey demonstrates that CRS and HIPEC is now performed on a large scale for CRC-PM patients. Variation in treatment may result in heterogeneity in surgical and oncological outcomes, emphasising the necessity to reach consensus on several issues of this comprehensive procedure. Future initiatives directed at achieving an international consensus statement are needed.

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.

A comprehensive treatment for peritoneal metastases from gastric cancer with curative intent.

Recently, Peritoneal Surface Oncology Group International (PSOGI) developed a novel comprehensive treatment consisting of cytoreductive surgery (CRS) and perioperative chemotherapy (POC) for the treatment of peritoneal metastases (PM) from gastric cancer with curative intent. This article reviews the results of this treatment and verifies its indication. In this strategy, peritoneal cancer index (PCI) is determined by laparoscopy, and a peritoneal port is placed. Neoadjuvant bidirectional intraperitoneal/systemic chemotherapy (NIPS) is performed for 3 cycles, and then laparotomy is performed. Cytoreductive surgery with peritonectomy procedures and hyperthermic intraperitoneal chemoperfusion (HIPEC) are performed. Multivariate analyses showed that completeness of cytoreduction, pathologic response to NIPS and PCI level and cytologic status after NIPS, as independent prognostic factors. PCI less than cut-off level after NIPS, negative cytology after NIPS, and positive response to NIPS were identified as the indications for comprehensive treatment. Patients who hold these criteria should be considered as the candidates for CRS and HIPEC.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in 1000 patients with perforated appendiceal epithelial tumours.

PURPOSE: To report early and long term outcomes following cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in 1000 patients with perforated appendiceal epithelial tumours, predominantly with pseudomyxoma peritonei (PMP). METHODS: Retrospective analysis of a prospective database of 1000 consecutive patients undergoing CRS and HIPEC for perforated appendiceal tumours between 1994 and 2014 in a UK National Peritoneal Malignancy unit. RESULTS: Overall 1000/1444 (69.2%) patients treated for peritoneal malignancy had appendiceal primary tumours. Of these 738/1000 (73.8%) underwent complete cytoreductive surgery (CCRS), 242 (24.2%) had maximal tumour debulking (MTD) and 20 (2%) had laparotomy and biopsies only. Treatment related 30-day mortality was 0.8% in CCRS and 1.7% in MTD group with major postoperative morbidity rates of 15.2% (CCRS) and 14.5% (MTD). Five- and 10-year overall survival was 87.4% and 70.3% in the 738 patients who had CCRS compared with 39.2% and 8.1% respectively in the MTD group. On multivariate analysis, significant predictors of reduced overall survival were male gender (p = 0.022), elevated CEA (p = 0.001), elevated CA125 (p = 0.001) and high tumour grade or adenocarcinoma (p = 0.001). CONCLUSIONS: Perforated epithelial appendiceal tumours are rare, though may be increasing in incidence and can present unexpectedly at elective or emergency abdominal surgery, often with PMP. CRS and HIPEC results in good long term outcomes in most patients.

The results of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in 1200 patients with peritoneal malignancy.

AIM: The study determined the outcome of 1200 consecutive patients treated for peritoneal malignancy in one surgical unit over a 20-year period. METHOD: A retrospective analysis was conducted of a custom designed prospective database of patients undergoing surgery for peritoneal malignancy since 1994. Patient demographics, tumour type, extent of surgery and outcome were recorded. RESULTS: Between 1994 and January 2014 (when the 1200th case had undergone surgery) 2956 patients were referred with a diagnosis of peritoneal malignancy. Pseudomyxoma peritonei of appendiceal origin was the pathology in 956/1200 (79.7%) patients. Other aetiologies included colorectal peritoneal metastases [89/1200 (7.4%)], abdominal mesothelioma [65/1200 (5.4%)] and miscellaneous [90/1200 (7.5%)]. Overall 863/1200 (71.9%) had complete cytoreduction, 294 (24.5%) had maximal tumour debulking and 43 (3.6%) had laparotomy only. The proportion undergoing complete cytoreduction per quartile of 300 patients was 60.7%, 65.0%, 77.0% and 80.3%. Laparotomy and biopsy fell from 6.4% in the first quartile to 2.7%, 1.7% and 1.3% in subsequent quartiles. The 30-day mortality in the four quartiles was 3.0%, 1.0%, 0.7% and 0.7%. The 5-year survival was 84% in the 636 patients with appendix tumours who had complete cytoreduction, 76% in the 38 with abdominal mesothelioma and 44% in the 60 with colorectal peritoneal metastases. CONCLUSION: A centralized approach facilitated high volume experience in a single centre with an increase in the completeness of surgical excision rates and a reduction in mortality and morbidity over time.

Elevated tumour markers are normalized in most patients with pseudomyxoma peritonei 7 days after complete tumour removal.

AIM: Elevation of the preoperative tumour markers in pseudomyxoma peritonei (PMP) is common and is a risk factor for recurrence. There has, however, been no documentation of the effect of complete tumour removal on tumour markers levels after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). The aim of the study was to compare the tumour markers 7 days after surgery in patients with elevated preoperative levels. METHOD: This was an observational prospective study of patients with PMP of appendiceal origin treated in one of the UK National Referral Centres for this condition. Thirty patients [median age = 61 (range: 31-74) years; six men] with an elevated preoperative level of carcinoembryonic antigen (CEA), carbohydrate antigen 125 (CA-125) and/or carbohydrate antigen 19-9 (CA19-9) underwent repeated estimation, 7 days after CRS and HIPEC for PMP. RESULTS: The median preoperative CEA level of 12 µg/l fell to 0.75 µg/l postoperatively (P < 0.0001), CA-125 fell from 45 to 31 kU/l (P = 0.183) and CA19-9 fell from 134 to 37 kU/l (P = 0.003). The CEA was raised in 22 (73%) of 30 patients preoperatively and in two (7%) of 30 patients 7 days after surgery (P < 0.0001). The corresponding data for CA-125 were 18 (60%) and 13 (43%) (P = 0.196) and for CA19-9 they were 24 (80%) and 16 (53%) (P = 0.028). CONCLUSION: This is the first documentation of a reduction or normalization of CEA 7 days after CRS, but not for CA19-9 or CA-125. This may indicate completeness of surgical resection and could aid selection for adjuvant therapy and predict prognosis. Long-term follow-up is, however, necessary to determine the significance of this observation.

Risk of definitive stoma after surgery for peritoneal malignancy in 958 patients: comparative study between complete cytoreductive surgery and maximal tumor debulking.

INTRODUCTION: Complete cytoreductive surgery (CRS) can achieve cure or long-term survival in selected patients with peritoneal malignancy. In selected patients, due to extensive disease, complete tumour removal is impossible and optimal strategy may be maximal tumour debulking (MTD). We analysed the stoma related outcome in a series of patients undergoing surgery in a National Peritoneal Malignancy Referral Centre. METHODS: All patients who underwent CRS, with or without, intra-operative hyperthermic intraperitoneal chemotherapy (HIPEC) between 1994 and 2012 were included. Data was collected prospectively in an institutional database and analysed retrospectively. RESULTS: CRS was performed in 958 patients (female: 595, male: 363) of whom 781 (81.5%) had a primary appendix tumour, 63 (6.6%) had a colorectal primary, 47 (4.9%) peritoneal mesothelioma, 38 (4%) an ovarian tumour and 29 patients (3%) other tumours. Complete CRS was achieved in 72% (693/958). Overall 352/958 (37%) had a stoma, which was permanent in 165/958 (17.2%). The median time interval from CRS to reversal of stoma was 4.4 months (range: 1.4-13.8). Stomas were created in 113/265 (42.6%) at MTD (permanent: n = 105 (93%), temporary: n = 8 (7%)), and 239/693 (34.5%) at complete CRS (permanent: n = 60 (25%), temporary: n = 179 (75%)) (p = 0.020). All temporary stomas in the 168/693 (24.4%) of patients who had complete CRS were subsequently reversed. CONCLUSION: To achieve complete CRS for peritoneal malignancy a stoma is often required and in a proportion this will be permanent. Overall over one third had a stoma at surgery with almost half subsequently reversed.

Recurrence and outcome after complete tumour removal and hyperthermic intraperitoneal chemotherapy in 512 patients with pseudomyxoma peritonei from perforated appendiceal mucinous tumours.

BACKGROUND: Pseudomyxoma peritonei (PMP) usually originates from perforated mucinous appendiceal tumours and may present unexpectedly at surgery, or be suspected at cross sectional imaging. The optimal treatment involves macroscopic tumour removal by cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC). The 10-year Kaplan-Meier predicted disease-free survival is 61%. Some patients with recurrence are amenable to further CRS and HIPEC. AIM: To evaluate the outcomes of re-do surgery in a large single centre series of reoperation for recurrence of peritoneal surface malignancy. METHOD: Retrospective analysis of prospective database of 752 patients undergoing CRS for perforated appendiceal tumours analysed. Routine follow up involved annual CT scans and serum tumour marker measurement. The survival and recurrence in the 512/752 (68.1%) who had complete cytoreduction between March 1994 and January 2012 was calculated by Kaplan-Meier univariate analysis. RESULTS: Overall 137/512 (26.4%) developed recurrence and of those 35/137 (25.5%) underwent repeat surgery. Complete tumour removal was again achieved in 20/35 (57.1%). There were no postoperative deaths and no significant difference in early postoperative complications and length of stay compared to primary CRS surgery. The 5-year survival in the 375 without recurrence, the 35 who had re-do surgery and the 102 who had recurrence with no surgery was 90.9%, 79.0% and 64.5% respectively. CONCLUSION: Approximately one in four patients develops recurrence after complete CRS and HIPEC for PMP of appendiceal origin. Selected patients can undergo salvage surgery with good outcomes.

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.

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.

Pre-operative tumour marker status predicts recurrence and survival after complete cytoreduction and hyperthermic intraperitoneal chemotherapy for appendiceal Pseudomyxoma Peritonei: Analysis of 519 patients.

BACKGROUND: Cytoreductive surgery (CRS) combined with Hyperthermic Intraperitoneal Chemotherapy (HIPEC) is the optimal treatment for Pseudomyxoma Peritonei (PMP). Despite treatment, disease often recurs and may not be amenable to further CRS. Clinical experience suggests a spectrum of disease which may correlate with tumour marker levels. The aim of this study was to analyse the influence of markers on recurrence and survival. METHODS: The details of all patients undergoing surgery for PMP of appendiceal origin at a national centre for peritoneal malignancy were recorded in a dedicated prospective database. The data on all patients who had CRS and HIPEC between March 1994 and January 2012 was analysed and recurrence and survival correlated with pre-operative levels of CEA, CA-125 and CA19-9. RESULTS: Overall, 519 (69%) of 752 consecutive patients, underwent complete CRS and HIPEC. The median (range) age was 56 (20-82) years with 342/519 (66%) females. The mean overall (OS) and disease free survival (DFS) in the 131/519 patients who had normal preoperative tumour markers was 168 (128-207) and 125 (114-136) months respectively, significantly higher when compared with the 109/519 (21%) who had all three tumour markers elevated (OS of 65 (42-88) and DFS of 55 (41-70) months respectively) (P = 0.002). CONCLUSIONS: Elevated tumour markers predict an increased risk of recurrence and reduced survival after complete CRS. This may reflect cell biology in low grade tumours and is an independent prognostic feature. Further analysis may help to select patients for post-operative chemotherapy, second look procedures or stratification of follow up.

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.

Peritoneal metastases from colorectal cancer: patient selection for cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

Cytoreductive surgery (CRS) in combination with hyperthermic intraperitoneal chemotherapy (HIPEC) is an established treatment modality for patients with pseudomyxoma peritonei. The majority of patients with pseudomyxoma who have complete tumour removal and HIPEC are cured. Over the last decade CRS for peritoneal metastasis of colorectal origin has emerged as an effective treatment strategy in carefully selected patients. Although convincing evidence is limited, available data shows promising results. The key to a successful outcome is appropriate selection of patients. In patients with extensive peritoneal disease, where complete cytoreduction is not achieved, surgical treatment may not be beneficial and might impair quality of life. In this paper we discuss the challenges of selecting patients with colorectal peritoneal metastases who are likely to benefit from CRS with HIPEC.

Multi-institutional experience of diffuse intra-abdominal multicystic peritoneal mesothelioma.

BACKGROUND: This study was undertaken to measure survival of patients with multicystic peritoneal mesothelioma treated by cytoreductive surgery and hyperthermic intraperitoneal chemotherapy through a multi-institutional collaboration. METHODS: A multi-institutional data registry, established by the Peritoneal Surface Oncology Group, was used to identify patients with peritoneal mesothelioma and the subgroup with multicystic tumours, treated by cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. Outcomes for this subgroup are reported. The primary endpoint was overall survival. A secondary endpoint was the incidence of treatment-related complications. RESULTS: Of 405 patients with peritoneal mesothelioma, 26 (6·4 per cent) had multicystic tumours. There were 20 women and six men with a mean(s.d.) age of 42(12) years. The median peritoneal carcinomatosis index (PCI) was 14 (range 6-39). There was no perioperative mortality. Six patients developed grade III or IV complications. After a median follow-up of 54 (range 5-129) months, all 26 patients were still alive. CONCLUSION: Multicystic peritoneal mesothelioma appears to be a distinct subtype of peritoneal mesothelioma, where long-term survival may be achieved through cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

Iatrogenic perforation at colonic imaging.

AIM: Adequate colonic imaging is generally an invasive procedure with attendant risks, particularly perforation. Endoscopy, barium enema and computed tomographic colonography (CTC) are the main techniques for investigating patients with symptoms of, or screening for, colorectal cancer. The potential complications of these investigations have to be weighed against the benefits. This article reviews the literature on the incidence, presentation and management of iatrogenic colonic perforation at colonic imaging. METHOD: A literature review of relevant studies was undertaken using PubMed, Cochrane library and personal archives of references. Manual cross-referencing was performed, and relevant references from selected articles were reviewed. Studies reporting complications of endoscopy, barium enema and CT colonography were included in this review. RESULTS: Twenty-four studies were identified comprising 640,433 colonoscopies, with iatrogenic perforation recorded in 585 patients (0.06%). The reported perforation rate with double-contrast barium enema was between 0.02 and 0.24%. Serious complications with CTC were infrequent, though nine perforations were reported in a case series of 24,365 patients (0.036%) undergoing CTC. CONCLUSION: Perforation remains an infrequent and almost certainly under-reported, complication of all colonic imaging modalities. Risk awareness, early diagnosis and active management of iatrogenic perforation minimizes an adverse outcome.