Survival of Patients With Head and Neck Merkel Cell Cancer: Findings From the Pan-Canadian Merkel Cell Cancer Collaborative.

Importance: Merkel cell carcinoma (MCC) is an aggressive cutaneous neuroendocrine carcinoma. Due to its relatively low incidence and limited prospective trials, current recommendations are guided by historical single-institution retrospective studies. Objective: To evaluate the overall survival (OS) of patients in Canada with head and neck MCC (HNMCC) according to American Joint Committee on Cancer 8th edition staging and treatment modalities. Design, Setting, and Participants: A retrospective cohort study of 400 patients with a diagnosis of HNMCC between July 1, 2000, and June 31, 2018, was conducted using the Pan-Canadian Merkel Cell Cancer Collaborative, a multicenter national registry of patients with MCC. Statistical analyses were performed from January to December 2022. Main Outcomes and Measures: The primary outcome was 5-year OS. Multivariable analysis using a Cox proportional hazards regression model was performed to identify factors associated with survival. Results: Between 2000 and 2018, 400 patients (234 men [58.5%]; mean [SD] age at diagnosis, 78.4 [10.5] years) with malignant neoplasms found in the face, scalp, neck, ear, eyelid, or lip received a diagnosis of HNMCC. At diagnosis, 188 patients (47.0%) had stage I disease. The most common treatment overall was surgery followed by radiotherapy (161 [40.3%]), although radiotherapy alone was most common for stage IV disease (15 of 23 [52.2%]). Five-year OS was 49.8% (95% CI, 40.7%-58.2%), 39.8% (95% CI, 26.2%-53.1%), 36.2% (95% CI, 25.2%-47.4%), and 18.5% (95% CI, 3.9%-41.5%) for stage I, II, III, and IV disease, respectively, and was highest among patients treated with surgery and radiotherapy (49.9% [95% CI, 39.9%-59.1%]). On multivariable analysis, patients treated with surgery and radiotherapy had greater OS compared with those treated with surgery alone (hazard ratio [HR], 0.76 [95% CI, 0.46-1.25]); however, this was not statistically significant. In comparison, patients who received no treatment had significantly worse OS (HR, 1.93 [95% CI, 1.26-2.96)]. Conclusions and Relevance: In this cohort study of the largest Canada-wide evaluation of HNMCC survival outcomes, stage and treatment modality were associated with survival. Multimodal treatment was associated with greater OS across all disease stages.

The exploration of remote simulation strategies for the acquisition of psychomotor skills in medicine: a pilot randomized controlled trial.

Background: Progress in remote educational strategies was fueled by the advent of the COVID-19 pandemic. This pilot RCT explored the efficacy of a decentralized model of simulation based on principles of observational and peer-to-peer learning for the acquisition of surgical skills. Methods: Sixty medical students from the University of Montreal learned the running subcuticular suture in four different conditions: (1) Control group (2) Self-learning (3) Peer-learning (4) Peer-learning with expert feedback. The control group learned with error-free videos, while the others, through videos illustrating strategic sub-optimal performances to be identified and discussed by students. Performance on a simulator at the end of the learning period, was assessed by an expert using a global rating scale (GRS) and checklist (CL). Results: Students engaging in peer-to-peer learning strategies outperformed students who learned alone. The presence of an expert, and passive vs active observational learning strategies did not impact performance. Conclusion: This study supports the efficacy of a remote learning strategy and demonstrates how collaborative discourse optimizes the students' acquisition of surgical skills. These remote simulation strategies create the potential for implantation in future medical curriculum design.Trial Registration: NCT04425499 2020-05-06.

Impact of the 21-Gene Recurrence Score Assay on Treatment Decisions and Cost in Patients with Node-Positive Breast Cancer: A Multicenter Study in Quebec.

BACKGROUND: The 21-gene Breast Recurrence Score (RS) assay, "the assay", has led to a paradigm shift for patients with hormone receptor-positive, node-negative early breast cancer and is emerging as an important tool to assist physician-patient decisions in foregoing chemotherapy in node-positive patients. We wanted to better understand the impact of the RS assay in node-positive patients upon physician treatment decisions and treatment cost in Quebec, Canada. PATIENTS AND METHODS: We conducted a multicenter, prospective observational trial for Estrogen/Progesterone Receptor (ER/PR)- positive, Human Epidermal Growth Factor Receptor 2 (HER2)-negative breast cancer patients with 1-3 positive lymph nodes. Physicians completed a questionnaire indicating treatment choice prior to and post availability of RS results. The primary endpoint was change in the physician's recommendation for chemotherapy prior to and post assay results. Secondary endpoints included change in physician's expressed level of confidence, and changes in estimated cost of recommended treatments prior to and post assay results. RESULTS: For the entire cohort, physician recommendation for chemotherapy was reduced by an absolute 67.1% by knowledge of the RS assay result (P < .0001). Physician recommendation of chemotherapy was decreased by 75.9% for patients RS result <14 (P < .0001); and 67.5% for patients with RS result 14-25 (P < .0001). Changes in treatment recommendations were associated with an overall reduction in cost by 73.7% per patient, and after incorporating the cost of the RS test, a cost benefit of $823 CAN at 6-month follow-up. CONCLUSION: Altogether, we established that the assay led to a two-third reduction in the use of chemotherapy, and was a cost-effective approach for hormone receptor-positive, node-positive breast cancer.

A Canadian single-centre experience with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for abdominal malignancies.

BACKGROUND: Cytoreductive surgery in combination with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) has recently shown promise for the treatment of patients with various types of peritoneal carcinomatosis (PC). However, it is an extensive procedure that is associated with a variety of morbidities. We evaluated the safety and clinical outcomes of CRS-HIPEC performed at our centre. METHODS: Patients with abdominal malignancies who underwent CRS-HIPEC between February 2005 and December 2018 at the Centre hospitalier de l'Université de Montréal (CHUM) were retrospectively reviewed. RESULTS: A total of 141 patients were identified (66 with appendiceal cancer, 62 with colorectal cancer, 10 with mesothelioma and 3 with small intestinal tumours). The median age was 55 years. Median overall survival (OS) was not reached for patients with appendiceal tumours; it was 38.3 months for colorectal cancers. Among patients with colorectal cancer, survival was significantly better for those who received intraperitoneal HIPEC with oxaliplatin (74.9 mo) compared with mitomycin C (29.1 mo) (p = 0.006). Complete cytoreductive surgery and low peritoneal carcinomatosis index were associated with the highest overall survival in patients with appendiceal tumours and those with colorectal tumours. CONCLUSION: CRS-HIPEC can be performed with acceptable morbidity in patients with PC. These results validate the outcomes of previously reported trials, but further prospective trials are warranted to determine which patients will most benefit from the addition of HIPEC to CRS.

Targeted Axillary Dissection in Node-Positive Breast Cancer: A Retrospective Study and Cost Analysis.

Introduction Targeted axillary dissection (TAD) is a novel technique in the field of surgical oncology. During TAD, patients with node-positive breast cancer who clinically responded to neoadjuvant chemotherapy undergo resection of a previously proven metastatic node together with sentinel lymph node dissection (SLND). We aimed to assess the success rates of seed insertion and seed retrieval in the Canadian setting, as well as hospital costs of the procedure. Methods Patients converted to clinically node-negative status post-neoadjuvant chemotherapy underwent TAD. Before surgery, an iodine-125 radioactive seed was inserted in the previously proven metastatic node. The seed node was resected together with an SLND. Axillary lymph node dissection (ALND) was performed in all patients with residual metastases. Results Radioactive seeds were successfully inserted in 34/35 patients. In 34 patients, the targeted node was successfully resected with the radioactive probe during TAD. In one patient, the seed was retrieved inferiorly in the axilla during surgery. There was no adverse event. In total, 50% (17/34) of patients had no residual metastases and were able to avoid ALND. Eight out of 17 patients who underwent ALND did not have any residual disease in their specimen. The mean cost of TAD was 25% superior to the mean cost of ALND (p = 0.02). However, the mean total cost of the hospital stay for TAD was 20% superior to the mean cost of ALND (p = 0.11). The mean cost of TAD was 4,322 Can$ (Canadian dollars), similar to the mean cost of both ALND and SLND performed during the same procedure (4,479 Can$). Conclusions TAD was successful in 97% of patients. Despite increased procedural costs, with a lesser impact on total hospital stay costs, TAD was beneficial in 50% of patients. These patients avoided the unnecessary morbidity associated with ALND.

Evidence-Based Strategies for the Treatment of Peritoneal Malignancies during Health Care Resource Restriction: The COVID-19 Pandemic.

Background: The COVID-19 pandemic has put enormous pressure on hospital resources, and has affected all aspects of patient care. As operative volumes decrease, cancer surgeries must be triaged and prioritized with careful thought and attention to ensure maximal benefit for the maximum number of patients. Peritoneal malignancies present a unique challenge, as surgical management can be resource intensive, but patients have limited non-surgical treatment options. This review summarizes current data on outcomes and resource utilization to help inform decision-making and case prioritization in times of constrained health care resources. Methods: A rapid literature review was performed, examining surgical and non-surgical outcomes data for peritoneal malignancies. Narrative data synthesis was cross-referenced with relevant societal guidelines. Peritoneal malignancy surgeons and medical oncologists reviewed recommendations to establish a national perspective on case triage and mitigating treatment strategies. Results and Conclusions: Triage of peritoneal malignancies during this time of restricted health care resource is nuanced and requires multidisciplinary discussion with consideration of individual patient factors. Prioritization should be given to patients where delay may compromise resectability of disease, and where alternative treatment options are lacking. Mitigating strategies such as systemic chemotherapy and/or surgical deferral may be utilized with close surveillance for disease stability or progression, which may affect surgical urgency. Unique hospital capacity, and ability to manage the complex post-operative course for these patients must also be considered to ensure patient and system needs are aligned.

The location of the primary colon cancer has no impact on outcomes in patients undergoing cytoreductive surgery for peritoneal metastasis.

BACKGROUND: The impact of the location of colorectal cancer on patient outcomes has been reported in several settings. The objective of this study was to assess the prognostic impact of the location of the primary colon cancer among patients with colorectal cancer peritoneal metastases undergoing complete cytoreductive surgery. METHODS: Using the prospectively maintained clinical and biological digestive peritoneal metastasis database of the BIG-RENAPE network, we identified 796 patients treated by a complete cytoreductive surgery between January 2004 and January 2017 for colorectal cancer peritoneal metastases in 16 different institutions. The 2 primary endpoints were overall survival and progression-free survival. To evaluate the impact on overall survival and progression-free survival of potential prognostic factors (including the location of the primary colorectal cancer), these factors were included in univariate and multivariate Cox proportional hazard models. RESULTS: Right-sided colorectal cancers were more often BRAF mutated and had microsatellite instability, whereas the frequency of RAS mutation was similar between right-sided and left-sided colorectal cancers. After a median follow-up time of 3.3 years, there was no significant difference in overall survival or progression-free survival according to tumor side. The lack of effect of tumor location on overall survival and progression-free survival was consistent across subgroups. CONCLUSION: Among patients undergoing complete cytoreductive surgery for peritoneal metastases, the site of the primary colorectal cancer was not associated with differences in progression-free survival or overall survival. Tumor side should not be used as a stratification factor in trials of colorectal cancer peritoneal metastases and should not be used in the selection process of patients for cytoreductive surgery.

A Novel Level I Oncoplastic Surgery Technique for Tumors Located in UIQ of the Breast Far from the Nipple: The "Cross" Technique.

Breast surgery was revolutionized with the use of oncoplastic reshaping techniques minimizing breast deformities and esthetic complications. However, the application of the current oncoplastic techniques becomes challenging in some situations such as small-size breasts and when the tumors are located in special locations of the breast, for example, upper inner quadrant. In this article, an optimized oncoplastic technique named the "Cross" technique is introduced to overcome the abovementioned problems in the surgery of breast tumors located in the upper inner quadrant far from the center of the breast. Nineteen oncoplastic surgeries were performed by the same breast surgeon. The mean diameter and weight of the excised specimens were 20 mm and 74 g. The mean age of the patients was 51 years. Clear surgical margins were obtained in all patients. There was no marked deformity in the breast after surgery. The optimized technique produced promising results in our hands when applied to a selected group of patients. Moreover, the technique was found to reduce the need for revision surgery in ptotic breasts, as the alteration in the shape of the breast undergoing surgery is not significant enough to introduce asymmetry to the breasts.

Comparative Evaluation of Iodine-125 Radioactive Seed Localization and Wire Localization for Resection of Breast Lesions.

PURPOSE: Radioactive seed localization (RSL) uses a titanium seed labeled with iodine-125 energy for surgery of nonpalpable breast lesions. RSL facilitates radiology-surgery scheduling and allows for improved oncoplasty compared with wire localization (WL). The purpose of this work was to compare the 2 techniques. METHODS: We performed a retrospective study of all breast lesions operated with RSL between February 2013 and March 2015 at our university institution, and compared with an equivalent number of surgeries performed with a single WL. Imaging and pathology reports were reviewed for information on guidance mode, accuracy of targeting, nature of excised lesion, size and volume of surgical specimen, status of margins, and reinterventions. RESULTS: A total of 254 lesions (247 women) were excised with RSL and compared with 257 lesions (244 women) whose surgery was guided by WL. Both groups were comparable in lesion pathology, guidance mode for RSL or WL positioning, and accuracy of targeting (98% correct). Mean delay between biopsy and surgery was 84 days for RSL versus 103 after WL (P = .04). No differences were noted after RSL or WL for surgical specimen mean weight, largest diameter, and volume excised. For malignancies, the rate of positive margins was comparable (2.8%-3%), with 5 of 10 women in the RSL group who underwent a second surgery displaying residual malignancy compared with 3 of 9 women in the WL group. CONCLUSIONS: RSL is safe and accurate, and has comparable surgical endpoints to WL. Because RSL offers flexible scheduling and facilitated oncoplasty, RSL may replace WL for resection of nonpalpable single breast lesions.

Registries on peritoneal surface malignancies throughout the world, their use and their options.

AIM: The treatment of peritoneal surface malignancies ranges from palliative care to full cytoreductive surgery (CRS) and heated intraperitoneal chemotherapy, HIPEC. Ongoing monitoring of patient recruitment and volume is usually carried out through dedicated registries. With multiple registries available worldwide, we sought to investigate the nature, extent and value of existing worldwide CRS and HIPEC registries. METHODS: A questionnaire was sent out to all known major treatment centres. The questionnaire covers: general purpose of the registry; inclusion criteria in the registry; the date the registry was first established; volume of patients in the registry and description of the data fields in the registries. Finally, the population size of the catchment area of the registry was collected. RESULTS: Twenty-seven questionnaires where returned. National databases are established in northwest European countries. There are five international general databases. Most database collect data on patients who have undergone an attempt to CRS and HIPEC. Two registries collect data on all patients with peritoneal carcinomatosis regardless the treatment. Most registries are primarily used for tracking outcomes and complications. When correlating the number of cases of CRS and HIPEC that are performed to the catchment area of the various registry, a large variation in the number of performed procedures related to the overall population was noted, ranging from 1.3 to 57 patients/million year with an average of 15 patients/1 million year. CONCLUSIONS: CRS and HIPEC is a well-established treatment for peritoneal surface malignancies worldwide. However, the coverage as well as the registration of treatment procedures differs widely. The most striking difference is the proportion of HIPEC procedures per capita which ranges from 1.3 to 57 patients per million. This suggests either a difference in patient selection, lack of access to HIPEC centres or lack of appropriate data collection.

Sentinel node biopsy after neoadjuvant chemotherapy in biopsy-proven node-positive breast cancer: the SN FNAC study.

PURPOSE: An increasing proportion of patients (> 30%) with node-positive breast cancer will obtain an axillary pathologic complete response after neoadjuvant chemotherapy (NAC). If sentinel node (SN) biopsy (SNB) is accurate in this setting, completion node dissection (CND) morbidity could be avoided. PATIENTS AND METHODS: In the prospective multicentric SN FNAC study, patients with biopsy-proven node-positive breast cancer (T0-3, N1-2) underwent both SNB and CND. Immunohistochemistry (IHC) use was mandatory, and SN metastases of any size, including isolated tumor cells (ypN0[i+], ≤ 0.2 mm), were considered positive. The optimal SNB identification rate (IR) ≥ 90% and false-negative rate (FNR) ≤ 10% were predetermined. RESULTS: From March 2009 to December 2012, 153 patients were accrued to the study. The SNB IR was 87.6% (127 of 145; 95% CI, 82.2% to 93.0%), and the FNR was 8.4% (seven of 83; 95% CI, 2.4% to 14.4%). If SN ypN0(i+)s had been considered negative, the FNR would have increased to 13.3% (11 of 83; 95% CI, 6.0% to 20.6%). There was no correlation between size of SN metastases and rate of positive non-SNs. Using this method, 30.3% of patients could potentially avoid CND. CONCLUSION: In biopsy-proven node-positive breast cancer after NAC, a low SNB FNR (8.4%) can be achieved with mandatory use of IHC. SN metastases of any size should be considered positive. The SNB IR was 87.6%, and in the presence of a technical failure, axillary node dissection should be performed. We recommend that SN evaluation with IHC be further evaluated before being included in future guidelines on the use of SNB after NAC in this setting.

Pharmacokinetics of intraperitoneal irinotecan in a pig model.

Complete surgical cytoreduction of peritoneal implants and immediate intraperitoneal (lP) chemotherapy offers the greatest survival in selected patients with peritoneal carcinomatosis. This study was undertaken to describe the metabolism and pharmacokinetics of normothermic intraperitoneal CPT-11, free and glucuronized SN-38, in a pig model. Thirteen pigs were used for experimentation. Animals were grouped for IV and IP CPT-1 1 administration. Eleven pigs underwent laparotomy through a midline incision and instillation of 100, 200, and 400mg IP CPT-11. Systemic venous blood, portal blood and peritoneal fluid samples were taken at 5, 10, 20, 30, and 45 min, then every hour up to 8 hr for the 100 mg. For the three groups, peritoneal CPT-11 exposition was on average 4.9 times greater in the peritoneum than in the systemic venous or portal circulations and the systemic CPT-11 fraction absorbed from the peritoneum linearly increased with time. Free SN-38 was measurable in the earliest peritoneal samples taken. The initial instillation dose of CPT-11 did not impact on the SN-38 converted fraction, which remained stable at approximately 0.04% during the first 4 hour. Mean peritoneal SN-38: CPT-11 AUC ratio was 0.043. OPT-11 peritoneal conversion into SN-38 appeared slightly Inferior to the systemic conversion ratio. This norrnothermic IP OPT-11 pharmacokinetic study performed in a pig model confirms the possibility to achieve at least a 30 times higher peritoneal than systemic exposure. Peritoneal exposure to active SN-38 begins at the moment of CPT-11 peritoneal instillation. A fixed and small traction of less than 0.1% of CPT-11 is converted into SN-38, underlying the importance of a sufficient initial IP dose of CPT-11.

A phase II neoadjuvant trial of sequential nanoparticle albumin-bound paclitaxel followed by 5-fluorouracil/epirubicin/cyclophosphamide in locally advanced breast cancer.

BACKGROUND: Neoadjuvant chemotherapy has become standard treatment for women with locally advanced breast cancer (LABC). Various regimens have explored the addition of newer agents to determine safety and efficacy. The aim of this phase II study was to incorporate albumin-bound paclitaxel with sequential anthracycline-based therapy. PATIENTS AND METHODS: Sixty-six women with LABC but without prior treatment and regardless of hormone receptor or HER2 status were enrolled. All patients were to receive albumin-bound paclitaxel weekly for 12 weeks followed by 5-fluorouracil/ epirubicin/cyclophosphamide (FEC) every 3 weeks for 4 cycles. Trastuzumab was allowed in HER2-positive (HER2+) patients. Primary endpoint was pathologic complete response (pCR; CR) in breast. Secondary endpoints included pCR in breast and nodes, clinical CR, 2-year progression-free survival, and overall survival. RESULTS: Sixty-five patients received at least 1 dose of chemotherapy and were included in this analysis. Sixty-three patients completed 4 cycles of albumin-bound paclitaxel. Sixty-two patients received at least 1 dose of FEC, and 58 completed 4 cycles. Seventeen of 19 HER2+ women received trastuzumab. The pCR in breast was 29% (19 of 65). For the HER2+ subset, the pCR was 58% (11 of 19). Both albumin-bound paclitaxel and FEC were well tolerated. The most significant toxicities were grade 2/3 neuropathy (16%) with albumin-bound paclitaxel and grade 3/4 febrile neutropenia (7%) with FEC. CONCLUSION: Albumin-bound paclitaxel given over 12 weeks is well tolerated. Albumin-bound paclitaxel should be further evaluated in a randomized setting in both adjuvant and neoadjuvant trials.

Validation study of the s classification for melanoma patients with positive sentinel nodes: the Montreal experience.

BACKGROUND: Standard of care is to perform a complete lymph node dissection (CLND) in melanoma patients with positive sentinel lymph nodes (SLNs). However, less than 20% will have metastases in non-SLNs. The S classification was described to predict the non-SLN status, hoping to identify a subset of patients who can be spared the CLND. We tried to validate the feasibility and usefulness of this classification. MATERIALS AND METHODS: We performed a retrospective chart review. All melanoma cases between 1996 and 2006 were included, and 359 patients with SLN biopsies were identified. All pathology slides were reviewed with an emphasis on the S classification. RESULTS: There were 365 SLN biopsies performed. A total of 82 patients (22.8%) had positive SLNs, while 277 patients (77.2%) had negative SLNs. There were 22 patients classified as SI, 18 as SII, 37 as SIII, and 5 were unclassified. On CLND, only 10 patients (12.2%) had positive non-SLNs. None of these were classified as SI while 2 patients (11%) were classified as SII and 8 (22%) as SIII. The S category was found to be a predictor of non-SLN status, and this reached statistical significance (P = 0.044). On univariate analysis, only an increasing Breslow depth and ulceration were predictive of a non-SI status. CONCLUSION: Our results suggest that the S classification is easily feasible and predicts the status of non-SLNs. No patient with SI status was found to have additional non-SLN positive nodes. A larger-scale, prospective trial should be done to confirm these results and possibly spare patients the morbidity of CLND with a positive SLN.

Technical aspects of cytoreductive surgery.

At the Fifth International Workshop on Peritoneal Surface Malignancy, in Milan, the consensus on technical aspects of cytoreductive surgery (CRS) for peritoneal surface malignancy was obtained through the Delphi process. Five conflicting points were discussed: radicality of the peritonectomy procedure, cytoreduction of neoplastic nodules <2.5 mm, the timing of bowel anastomoses in relation to hyperthermic intraperitoneal chemotherapy (HIPEC) and indications of protective ostomies. According to the panel of experts a partial parietal peritonectomy restricted to the macroscopically involved regions could be indicated in all listed clinical conditions with the exception of peritoneal mesothelioma. No expert was of the opinion that a radical parietal peritonectomy is advisable irrespective of the disease being treated. All the experts agreed that electrovaporization of small (<2.5 mm) non-infiltrating metastatic nodules in the mesentery would be appropriate, even if theoretically the HIPEC affords microscopic cytoreduction. The panel also agreed that in the closed technique for HIPEC administration the intestinal anastomoses should be fashioned after completion of the perfusion. Finally when considering the place for protective ostomies the experts voted for a flexible approach allowing the surgeon to exercise discretion for individual patients.

Drugs, carrier solutions and temperature in hyperthermic intraperitoneal chemotherapy.

At the Fifth International Workshop on Peritoneal Surface Malignancy, in Milan, the consensus on technical aspects of cytoreductive surgery (CRS) for peritoneal surface malignancy was obtained through the Delphi process. Conflicting points concerning drugs, carrier solution and optimal temperature for hyperthermic intraperitoneal chemotherapy (HIPEC) were discussed.

Morbidity, toxicity, and mortality classification systems in the local regional treatment of peritoneal surface malignancy.

To reach a consensus for reporting complications related to cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Reporting the adverse events related to CRS + HIPEC is not standardized yet. Post-operative complications can be divided in two categories: the effects of surgical manipulation per se and the toxic effects of the heated intraoperative chemotherapy. Additive and/or synergistic effects also exist. Different centers have published their experience with regard to the complications associated with the procedure. Various classification systems have been used which makes a temptative comparison of the different techniques and results almost impossible. An effort was made here to review the existing major classification systems: The Bozzetti classification, the Clavien classification (and two proposed modifications from Feldman et al. and Elias et al.) and the Common terminology criteria for adverse events (CTCAE) version 3.0 of the National Institute of Health (NIH) criteria. A related document was sent to an international panel of experts. The CTCAE was adopted by the panel of experts as the unique classification system to be used for reporting complications related to CRS + HIPEC.

The Delphi approach to Attain consensus in methodology of local regional therapy for peritoneal surface malignancy.

At the Fifth International Workshop on Peritoneal Surface Malignancy (PSM), held in Milan, December 2006, the consensus on technical aspects of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) was obtained through the Delphi process. The following topics were discussed: pre-operative workup; eligibility to CRS + HIPEC; intra-operative staging system; technical aspects of surgery; residual disease classification systems; HIPEC: nomenclature and modalities; drugs, carrier solution and optimal temperature; morbidity grading systems. Conflicting points regarding above-mentioned topics were elaborated and voted in two rounds by a panel of international experts in local-regional therapy. The purpose of this manuscript is to describe the organization and the methodology of the consensus statements and to interpret and discuss the implications of the most striking results.