Impact of Perioperative Systemic Chemotherapy on Survival for Patients Who have Diffuse Malignant Peritoneal Mesothelioma Treated with CRS-HIPEC.

BACKGROUND: The available data on the role of perioperative systemic chemotherapy (SC) for diffuse malignant peritoneal mesothelioma (DMPM) patients undergoing (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is heterogeneous and unstandardized. This study aimed to evaluate the impact of SC on the survival outcomes of DMPM patients undergoing CRS-HIPEC and to identify prognostic factors that affect the decision to administer SC. METHODS: Patients who underwent CRS-HIPEC in the National Cancer Institute Milan (1995-2020) were retrospectively analyzed using propensity score-matching of known covariates. The patients were grouped into three groups: group A (neoadjuvant chemotherapy [NACT] and no-SC), group B (no-SC and adjuvant chemotherapy [ACT]), and group C (NACT and ACT). Overall survival (OS) and progression-free survival (PFS) were calculated using the Kaplan-Meir method, and prognostic factors were calculated using the Cox-regression method. RESULTS: After a median follow-up period of 45 months (95% confidence interval [CI], 6.348-83.652 months) for group A, 115 months (95% CI, 44.379-185.621 months) for group B, and 88 months (95% CI, 3.296-172.704 months) for group C, the study analyzed 154 DMPM patients consisting of matched group A (NACT: 60 + no-SC: 52 = 112), group B (ACT: 38 + no-SC: 38 = 76), and group C (NACT: 31 + ACT: 31 = 62). The patients undergoing ACT had better 5-year OS and PFS than the patients undergoing NACT. In the multivariate analysis, ACT was significantly associated with improved OS by 48% (hazard ratio [HR], 0.52; 95% CI, 0.280-0.965, p = 0.038). For PFS, the association of ACT did not reach statistical significance (HR, 0.531; 95% CI, 0.266-1.058; p = 0.072). CONCLUSION: The optimum treatment sequence for DMPM is CRS-HIPEC followed by adjuvant chemotherapy for high-risk patients. Upfront surgery appears preferable to NACT for patients amenable to complete CRS.

The 2022 PSOGI International Consensus on HIPEC Regimens for Peritoneal Malignancies: Pseudomyxoma Peritonei.

BACKGROUND: The combination of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) constitutes the established standard of care for pseudomyxoma peritonei patients. However, the role of HIPEC lacks validation through randomized trials, leading to diverse proposed treatment protocols. This consensus seeks to standardize HIPEC regimens and identify research priorities for enhanced clarity. METHODS: The steering committee applied the patient, intervention, comparator, and outcome method to formulate crucial clinical questions. Evaluation of evidence followed the Grading of Recommendations, Assessment, Development, and Evaluation system. Consensus on HIPEC regimens and research priorities was sought through a two-round Delphi process involving international experts. RESULTS: Out of 90 eligible panelists, 71 (79%) participated in both Delphi rounds, resulting in a consensus on six out of seven questions related to HIPEC regimens. An overwhelming 84% positive consensus favored combining HIPEC with CRS, while a 70% weak positive consensus supported HIPEC after incomplete CRS. Specific HIPEC regimens also gained consensus, with 53% supporting Oxaliplatin 200 mg/m2 and 51% favoring the combination of cisplatin (CDDP) associated with mitomycin-C (MMC). High-dose MMC regimens received an 89% positive recommendation. In terms of research priorities, 61% of panelists highlighted the importance of studies comparing HIPEC regimens post CRS. The preferred regimens for such studies were the combination of CDDP/MMC and high-dose MMC. CONCLUSIONS: The consensus recommends the application of HIPEC following CRS based on the available evidence. The combination of CDDP/MMC and high-dose MMC regimens are endorsed for both current clinical practice and future research efforts.

The 2022 PSOGI International Consensus on HIPEC Regimens for Peritoneal Malignancies: HIPEC Technologies.

This manuscript reports the results of an international consensus on technologies of hyperthermic intraperitoneal perioperative chemotherapy (HIPEC) performed with the following goals: To provide recommendations for the technological parameters to perform HIPEC. To identify the role of heat and its application forms in treating peritoneal metastases. To provide recommendations regarding the correct dosimetry of intraperitoneal chemotherapy drugs and their carrier solutions. To identify for each intraperitoneal chemotherapy regimen the best dosimetry and fractionation. To identify areas of future research pertaining to HIPEC technology and regimens. This consensus was performed by the Delphi technique and comprised two rounds of voting. In total, 96 of 102 eligible panelists replied to both Delphi rounds (94.1%) with a consensus of 39/51 questions on HIPEC technical aspects. Among the recommendations that met with the strongest consensus were those concerning the dose of HIPEC drug established in mg/m2, a target temperature of at least 42°C, and the use of at least three temperature probes to pursue hyperthermia. Ninety minutes as the ideal HIPEC duration seemed to make consensus. These results should be considered when designing new clinical trials in patients with peritoneal surface malignancies.

2022 Peritoneal Surface Oncology Group International Consensus on HIPEC Regimens for Peritoneal Malignancies: Colorectal Cancer.

BACKGROUND: Selected patients with peritoneal metastases of colorectal cancer (PM-CRC) can benefit from potentially curative cytoreductive surgery (CRS) ± hyperthermic intraperitoneal chemotherapy (HIPEC), with a median overall survival (OS) of more than 40 months. OBJECTIVE: The aims of this evidence-based consensus were to define the indications for HIPEC, to select the preferred HIPEC regimens, and to define research priorities regarding the use of HIPEC for PM-CRC. METHODS: The consensus steering committee elaborated and formulated pertinent clinical questions according to the PICO (patient, intervention, comparator, outcome) method and assessed the evidence according to the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) framework. Standardized evidence tables were presented to an international expert panel to reach a consensus (4-point, weak and strong positive/negative) on HIPEC regimens and research priorities through a two-round Delphi process. The consensus was defined as ≥ 50% agreement for the 4-point consensus grading or ≥ 70% for either of the two combinations. RESULTS: Evidence was weak or very weak for 9/10 clinical questions. In total, 70/90 eligible panelists replied to both Delphi rounds (78%), with a consensus for 10/10 questions on HIPEC regimens. There was strong negative consensus concerning the short duration, high-dose oxaliplatin (OX) protocol (55.7%), and a weak positive vote (53.8-64.3%) in favor of mitomycin-C (MMC)-based HIPEC (preferred choice: Dutch protocol: 35 mg/m2, 90 min, three fractions), both for primary cytoreduction and recurrence. Determining the role of HIPEC after CRS was considered the most important research question, regarded as essential by 85.7% of the panelists. Furthermore, over 90% of experts suggest performing HIPEC after primary and secondary CRS for recurrence > 1 year after the index surgery. CONCLUSIONS: Based on the available evidence, despite the negative results of PRODIGE 7, HIPEC could be conditionally recommended to patients with PM-CRC after CRS. While more preclinical and clinical data are eagerly awaited to harmonize the procedure further, the MMC-based Dutch protocol remains the preferred regimen after primary and secondary CRS.

Education and Training in Peritoneal Surface Oncology.

Peritoneal surface oncology (PSO) is a novel field dealing with the knowledge of peritoneal neoplasms, primary or secondary, and their clinical management. As a specific treatment with curative intent for peritoneal neoplasms developed over the years, there is a growing need to comprehensively educate and train surgical oncologists worldwide in this discipline, a recognized unmet need. The European School of Peritoneal Surface Oncology (ESPSO) emerged in 2014 to provide an answer to this need.

Guidelines for the Prophylaxis and Treatment of Peritoneal Metastases From Colorectal Cancer: A GRADE-Approach for Evidence Evaluation and Recommendations.

Colorectal peritoneal metastases (CPM) are common in colorectal cancer patients. This article aims to provide GRADE guidelines for the use of hyperthermic intraperitoneal chemotherapy (HIPEC) in two clinical situations: (1) To determine the value of adjuvant HIPEC for the prevention of CPM in high-risk colorectal cancer patients; (2) to determine the impact on survival of cytoreductive surgery and HIPEC followed by adjuvant systemic chemotherapy as compared to systemic chemotherapy alone in patients with CPM.

A combinatorial culture strategy to develop pseudomyxoma peritonei organoid models.

BACKGROUND AND OBJECTIVES: Few preclinical models of pseudomyxoma peritonei (PMP) have been developed, probably due to the tumor's low incidence and its peculiar characteristics of slow growth. Therefore, there is a need to develop more refined PMP models that better reflect its characteristics. The aim of the study is to develop a culture strategy to generate organoid models derived from PMP patient samples. METHODS: We followed a strategy based on combinatorial culture conditions that include the different factors essential for PMP growth and that mimic the microenvironment present in the patients. RESULTS: We cultured PMP samples in the presence of the various factors produced by the niche environment of PMP. We obtained 12 PMP organoid models, each of which grows under specific culture conditions. PMP-derived organoids show long-term expansion capacity and reproduce the genetic landscape and histological phenotype of the tumor of origin. CONCLUSION: The organoids we developed faithfully reproduce the key features of PMP disease and will allow us to understand the biology of PMP. With them, we will be able to identify key regulatory networks that support PMP progression, providing a platform for multilevel preclinical testing, identify novel diagnostic biomarkers, and generate novel targets for patient treatments.

Review of 2022 PSOGI/RENAPE Consensus on HIPEC.

The 2022 PSOGI (Peritoneal Surface Oncology Group International) and RENAPE (French Network for Rare Peritoneal Malignancies) consensus on hyperthermic intraperitoneal chemotherapy (HIPEC) was a comprehensive effort aimed at standardizing treatment protocols for various peritoneal malignancies. This initiative is critical due to the wide range of technical variations in HIPEC procedures and the resulting need for standardization to ensure consistent and effective patient care and meaningful audit of multicenter data.

2022 PSOGI Consensus on HIPEC Regimens for Peritoneal Malignancies: Diffuse Malignant Peritoneal Mesothelioma.

BACKGROUND: Diffuse malignant peritoneal mesothelioma (DMPM) is a rare and aggressive primary peritoneal disease, with recommended treatment, in eligible patients, of a combination of complete cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). As treatment is multimodal, there is a wide heterogeneity of HIPEC protocols precluding clear comparisons. Standardization at an international level is required. METHODS: The Peritoneal Surface Oncology Group International (PSOGI) designated a steering committee to produce consensus recommendations for HIPEC regimens, adapted to each etiology. The Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) methodology was used, based on a systematic review focused on main outcomes related to HIPEC regimens in DMPM patients and on the patient, intervention, comparator, and outcome (PICO) method to elaborate main questions. An opinion survey was added. Furthermore, a Delphi process was performed with voting from a panel of international experts. RESULTS: Eleven questions were elaborated, including two for future research requirements and three to assess the HIPEC regimen preference of the panel. The level of evidence underlying questions was globally low. Overall, 75 (86%) and 67 (77%) of the 87 invited experts completed the vote at the first and second round, respectively. HIPEC following complete CRS was strongly supported by 88% of voters with no need to plan comparative studies with CRS alone for 61.2% of voters. Bi-drug regimens appeared to be preferred to mono-drug ones and cisplatin was globally favored. The opinion survey confirmed the combination of cisplatin and doxorubicin as the recommended regimen. CONCLUSION: International consensus confirmed the indication of HIPEC following complete CRS in DMPM patients and recommended cisplatin-doxorubicin as the first-line HIPEC regimen.

The 2022 PSOGI International Consensus on HIPEC Regimens for Peritoneal Malignancies: Methodology.

BACKGROUND: A group of experts from the Peritoneal Surface Oncology Group International (PSOGI) and the BIG-RENAPE group carried out a consensus among surgeons experienced in treating peritoneal malignancies from around the world to derive recommendations on indications of hyperthermic intraperitoneal chemotherapy (HIPEC), choice and details of HIPEC regimens, and areas for future research. This manuscript describes the methodology of achieving this consensus and the degree of participation of experts. METHODS: The Delphi technique was used and the questionnaire comprised three categories: evidence-based recommendations using the GRADE (Grades of Recommendation, Assessment, Development, and Evaluation) system with the PICO (patient, intervention, comparison, and outcome) method, an opinion survey, and research recommendations. A consensus was achieved if any one option had >50% of votes, or positive or negative recommendations combined had > 70% of votes. RESULTS: Of the 145 experts solicited, 71.1% in round I and 72.2% in round II took the survey. Participation was highest among surgeons treating both gastrointestinal and gynecological malignancies. Of 113 questions, after round I, a consensus was achieved for 72 (63.7%) questions, and after the second round, consensus was achieved for another 22 (19.4%) questions, making a total of 94 (83.1%) questions for which a consensus was achieved. CONCLUSION: This consensus was carried out using a thorough review of literature and robust rating of evidence, and included key experts and opinion leaders from across the world. The results could guide clinicians on the use of HIPEC, both in their day-to-day clinical practice and in designing clinical trials.

Relapse of Pseudomyxoma Peritonei After Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy: Pattern of Failure, Clinical Management and Outcomes.

INTRODUCTION: Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) have dramatically improved pseudomyxoma peritonei (PMP) prognosis, but treatment failures are still a concern. We investigated the pattern of failure, treatment and outcomes of progressing disease. METHODS: A prospective database of 374 PMP patients was reviewed, and 152 patients relapsing after complete CRS/HIPEC were identified. PMP was graded according to the Peritoneal Surface Oncology Group International (PSOGI) classification. Hematogenous metastases and non-regional lymph node involvement were considered as systemic metastases. RESULTS: Median follow-up was 78.3 months (95% confidence interval [CI] 66.7-90.4). PMP relapse involved the peritoneum in 112 patients, pleural cavity in 8, both peritoneum and pleura in 8, systemic sites in 11, and both peritoneum and systemic sites in 13 patients. Systemic metastases involved the lung (n = 14), liver (n = 4), distant nodes (n = 3), bone (n = 2), and both lung and distant nodes (n = 1). Survival after diagnosis of PMP relapse was independently associated with curative versus palliative treatment (hazard ratio [HR] 0.52, 95% CI 0.36-0.75; p = 0.001) and PSOGI histology (HR 1.80, 95% CI 1.19-2.74; p = 0.005), but was not influenced by site of failure (p = 0.444). Ten-year overall survival was 77.5% for 62 patients who had curative-intent surgery for PMP relapse, compared with 83.0% for 192 patients who had no recurrences (p = 0.154) and 26.1% for 90 patients who underwent palliative treatments (p = 0.001). CONCLUSIONS: Relapse after CRS/HIPEC most commonly involves the peritoneum, but pleural recurrences and systemic metastases occur in a small but clinically relevant number of patients. In selected patients, surgical resection of recurrent disease can result in long survival, irrespective of sites of failure.

Impact of Previous Gynecologic Surgical Procedures on Outcomes of Non-Gynecologic Peritoneal Malignancies Mimicking Ovarian Cancer: Less Is More?

BACKGROUND: Non-gynecologic rare peritoneal surface malignancies (PSMs) often are misdiagnosed as disseminated ovarian cancer and initially treated by gynecologic surgeons. This study aimed to assess whether these previous maneuvers (i.e., full surgical staging and/or cytoreductive attempts) affect outcomes after the definitive surgery performed in a tertiary center. METHODS: The study reviewed 298 women affected by non-gynecologic PSM who underwent cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) after previous gynecologic surgery. Prior surgery was categorized as limited surgery (pLS: abdominal exploration with biopsy plus adnexectomy and/or appendectomy) or extended surgery (pES: full surgical staging or cytoreductive attempts including hysterectomy with bilateral salpingo-oophorectomy). RESULTS: Of the 298 patients, 143 had pLS and 153 had pES. Morbidity was similar between the groups (P = 0.143), but the pES group had more severe urinary tract injuries (19 vs. 3; P < 0.001), longer operating time (585.9 vs. 506.7; P = 0.027), and more patients needing more than two anastomoses (41 vs. 26; P = 0.033). Age older than 55 years (odds ratio [OR] 2.42; P = 0.009) and number of anastomoses (OR 3.17; P = 0.002) correlated with severe morbidity; pES correlated with urinary tract grades 3 and 4 injuries (OR 7.9; P = 0.001). The 5-year cumulative incidence of locoregional relapse was significantly higher in the pES group (0.41 vs. 0.27; P = 0.012; median follow-up period, 69 months). The multivariate analysis identified a Peritoneal Carcinomatosis Index (PCI) higher than 20 and pES as independent risk factors. CONCLUSION: For women undergoing CRS±HIPEC for non-gynecologic PSM, the risk for locoregional relapse and severe postsurgical urinary tract complications is increased by pES. Therefore, prior full surgical staging or cytoreductive attempts without definitive gynecologic histology should be avoided. Prophylactic ureteral stenting and stricter oncologic follow-up assessment must be considered in this scenario.

HIPEC Methodology and Regimens: The Need for an Expert Consensus.

BACKGROUND: Hyperthermic intraperitoneal chemotherapy (HIPEC) is performed with a wide variation in methodology, drugs, and other elements vital to the procedure. Adoption of a limited number of regimens could increase the collective experience of peritoneal oncologists, make comparison between studies more meaningful, and lead to a greater acceptance of results from randomized trials. This study aimed to determine the possibility of standardizing HIPEC methodology and regimens and to identify the best method of performing such a standardization. METHODS: A critical review of preclinical and clinical studies evaluating the pharmacokinetic aspects of different HIPEC drugs and drug regimens, the impact of hyperthermia, and the efficacy of various HIPEC regimens as well as studies comparing different regimens was performed. RESULTS: The preclinical and clinical data were limited, and studies comparing different regimens were scarce. Many of the regimens were neither supported by preclinical rationale or data nor validated by a dose-escalating formal phase 1 trial. All the regimens were based on pharmacokinetic data and did not take chemosensitivity of peritoneal metastases into account. Personalized medicine approaches such as patient-derived tumor organoids could offer a solution to this problem, although clinical validation is likely to be challenging. CONCLUSIONS: Apart from randomized trials, more translational research and phases 1 and 2 studies are needed. While waiting for better preclinical and clinical evidence, the best way to minimize heterogeneity is by an expert consensus that aims to identify and define a limited number of regimens for each indication and primary site. The choice of regimen then can be tailored to the patient profile and its expected toxicity and the methodology according regional factors.

Prognostic Impact of Primary Side and RAS/RAF Mutations in a Surgical Series of Colorectal Cancer with Peritoneal Metastases.

BACKGROUND: Selecting patients with colorectal cancer peritoneal metastases (CRC-PMs) for surgery is still a concern. Biological features have the potential to improve prognostic stratification, but their significance in this clinical setting is still unclear. We assessed the prognostic impact of primary side and KRAS/NRAS/BRAF/PIK3CA mutations in patients treated with either cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) or CRS alone. METHODS: We reviewed a prospective database of 152 CRC-PM patients selected to undergo perioperative systemic chemotherapy and CRS with or without HIPEC. Extensive mutational analysis of KRAS, NRAS, BRAF, and PIK3CA was performed by polymerase chain reaction (PCR). In 68 patients, Ion Torrent next-generation sequencing technology was used to characterize the hotspot regions of 50 genes. RESULTS: The primary tumor was right-sided in 61 patients (40.1%) and left-sided in 91 patients (59.9%). Right-sided primaries were associated with mutated KRAS (p = 0.01) and normal carcinoembryonic antigen (CEA; p = 0.03). KRAS was mutated in 71/152 patients (46.7%), NRAS in 7/152 patients (4.6%), BRAF in 10/152 patients (6.6%), PIK3CA in 17/78 patients (25.0%), TP53 in 37/68 patients (54.4%), APC in 25/68 patients (36.7%), SMAD4 in 13/68 patients (19.1%), and FBXW7 in 5/68 patients (7.4%). Median follow-up was 54.9 months and median survival from PM diagnosis was 45.1 months. The right-sided primary (hazard ratio [HR] 1.62, 95% confidence interval [CI] 0.43-0.89; p = 0.011), BRAF mutations (HR 2.21, 95% CI 1.05-4.63; p = 0.038), and Peritoneal Cancer Index (HR 1.47, 95% CI 1.03-2.10; p = 0.036) independently correlated with poorer survival, while APC mutations univariately correlated with better survival (p = 0.03). CONCLUSIONS: BRAF mutations and right-sided primary are adverse prognostic factors that may be used to optimize therapeutic strategies. APC may be involved in CRC-PM development and progression.

Colorectal Peritoneal Metastases Treated by Perioperative Systemic Chemotherapy and Cytoreductive Surgery With or Without Mitomycin C-Based HIPEC: A Comparative Study Using the Peritoneal Surface Disease Severity Score (PSDSS).

BACKGROUND: The Prodige-7 trial has questioned the role of hyperthermic intraperitoneal chemotherapy (HIPEC) in the treatment of peritoneal metastases from colorectal cancer (CRC-PM). PATIENTS AND METHODS: We compared a prospectively collected group of 48 patients undergoing oxaliplatin/irinotecan-based perioperative systemic chemotherapy (s-CT) with targeted agents, and cytoreductive surgery (CRS) (no-HIPEC group) with 48 controls undergoing the same perioperative s-CT and CRS/HIPEC (HIPEC group). Patients were matched (1:1) according to the Peritoneal Surface Disease Severity Score, completeness of cytoreduction, history of extraperitoneal disease (EPD), and Peritoneal Cancer Index. RESULTS: The groups were comparable, except for a higher number of patients in the HIPEC group with World Health Organization performance status 0, pN2 stage primary tumor, and treated with preoperative s-CT. Forty-one patients in the no-HIPEC group and 43 patients in the HIPEC group had optimal comprehensive treatment (P = 0.759), defined as complete cytoreduction of PM and margin-negative EPD resection. Median follow-up was 31.6 months in the no-HIPEC group and 39.9 months in the HIPEC group. Median overall survival was 39.3 months in the no-HIPEC group and 34.8 months in the HIPEC group (P = 0.702). In the two groups, severe morbidity occurred in 14 (29.2%) and 13 (27.1%) patients, respectively (P = 1.000), with no operative deaths. On multivariate analysis, left-sided primary and curative treatment independently correlated with better survival while HIPEC did not (hazard ratio 0.73; 95% confidence interval 0.47-1.15; P = 0.178). CONCLUSIONS: Our results confirmed that, in selected patients, perioperative s-CT and surgical treatment of CRC-PM resulted in unexpectedly high survival rates. Mitomycin C-based HIPEC did not increase morbidity but did not impact prognosis.

A Pilot Study of the Predictive Potential of Chemosensitivity and Gene Expression Assays Using Circulating Tumour Cells from Patients with Recurrent Ovarian Cancer.

Circulating tumour cells (CTCs) from liquid biopsies are under current investigation in several cancers, including epithelial ovarian cancer (EOC) but face significant drawbacks in terms of non-standardised methodology, low viable cell numbers and accuracy of CTC identification. In this pilot study, we report that chemosensitivity assays using liquid biopsy-derived metastatic EOC CTCs, from 10 patients, nine with stage IIIC and one with stage IV disease, in progression after systemic chemotherapy, submitted for hypoxic isolated abdominal perfusion (HAP), are both feasible and useful in predicting response to therapy. Viable metastatic EOC CTCs (>5 cells/mL for all 10 blood samples), enriched by transient culture and identified by reverse transcription polymerase chain reaction (RT-PCR) and indirect immunofluorescence (IF), were subjected to flow cytometry-based Annexin V-PE assays for chemosensitivity to several chemotherapeutic agents and by RT-PCR for tumour gene expression profiling. Using a cut-off value of >80% cell death, CTC chemosensitivity tests were predictive of patient RECIST 1.1 responses to HAP therapy associated with 100% sensitivity, 50% specificity, 33% positive predictive, 100% negative predictive and 60% accuracy values. We propose that the methodology employed in this study is feasible and has the potential to predict response to therapy, setting the stage for a larger study.

Iterative cytoreductive surgery with or without hyperthermic intraperitoneal chemotherapy for colorectal peritoneal metastases: A multi-institutional experience.

BACKGROUND AND OBJECTIVES: The aims of this multi-institutional study were to assess the feasibility of iterative cytoreductive surgery (iCRS)/hyperthermic intraperitoneal chemotherapy, iCRS in colorectal peritoneal carcinomatosis (CRPC), evaluate survival, recurrence, morbidity and mortality outcomes, and identify prognostic factors for overall survival. METHODS: Patients with CRPC that underwent an iCRS, with or without intraperitoneal chemotherapy, from June 1993 to July 2016 at 13 institutions were retrospectively analyzed from prospectively maintained databases. RESULTS: The study comprised of 231 patients, including 126 females (54.5%) with a mean age at iCRS of 51.3 years. The iterative high-grade (3/4) morbidity and mortality rates were 23.4% and 1.7%, respectively. The median recurrence-free survival was 15.0 and 10.1 months after initial and iCRS, respectively. The median and 5-year survivals were 49.1 months and 43% and 26.4 months and 26% from the initial and iCRS, respectively. Independent negative predictors of survival from the initial CRS included peritoneal carcinomatosis index (PCI) > 20 ( P = 0.02) and lymph node positivity ( P = 0.04), and from iCRS, PCI > 10 ( P = 0.03 for PCI 11-20; P < 0.001 for PCI > 20), high-grade complications ( P = 0.012), and incomplete cytoreduction ( P < 0.001). CONCLUSION: iCRS can provide long-term survival benefits to highly selected colorectal peritoneal carcinomatosis patients with comparable mortality and morbidity rates to the initial CRS procedure. Careful patient selection is necessary to improve overall outcomes.

Molecular Signatures for Combined Targeted Treatments in Diffuse Malignant Peritoneal Mesothelioma.

Background-There are currently no effective therapies for diffuse malignant peritoneal mesothelioma (DMPM) patients with disease recurrence. In this study, we investigated the biology of DMPM by analyzing the EGFR family, Axl, and MET, in order to assess the presence of cross-talk between these receptors, suggesting the effectiveness of combined targeted treatments in DMPM. Method-We analyzed a series of 22 naïve epithelioid DMPM samples from a single institute, two of which showed higher-grade malignancy ("progressed"). EGFR, HER2, HER3, Axl, and MET activation and expression were investigated by biochemical analysis, real-time PCR immunofluorescence, immunohistochemistry, next-generation sequencing, miRNA, and mRNA in situ hybridization. Results-In most DMPMs, a strong EGFR activation was associated with HER2, HER3, Axl, and MET co-activation, mediated mainly by receptor heterodimerization and autocrine-paracrine loops induced by the expression of their cognate ligands. Axl expression was downregulated by miRNA34a. Mutations in MET Sema domain were exclusively found in two "progressed" DMPMs, and the combined Axl and MET inhibition reduced cellular motility in a DMPM cell line obtained from a "progressed" DMPM. Conclusion-The results indicate that the coordinated activity of multiple cross-talks between RTKs is directly involved in the biology of DMPM, suggesting the combined inhibition of PIK3 and mTOR as an effective strategy that may be easily implemented in clinical practice, and indicating that the combined inhibition of EGFR/HER2 and HER3 and of Axl and MET deserves further investigation.

Dose-Dependent Effect of Red Blood Cells Transfusion on Perioperative and Long-Term Outcomes in Peritoneal Surface Malignancies Treated with Cytoreduction and HIPEC.

BACKGROUND: Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are associated with increased red blood cell transfusion (RBT) demand. Although the deleterious effects of RBT are documented in various settings, its effect in this setting is obscure. In this study, we evaluated the effects of different-grade RBT on the short- and long-term outcomes of CRS and HIPEC. METHODS: We analyzed 231 patients with diffuse malignant peritoneal mesothelioma (DMPM) and 273 patients with pseudomyxoma peritonei (PMP) operated in our unit. RBT was categorized according to the amount of packed red blood cell units (PRBCs) administered (0, 1-2, 3-5, > 6). The effects of RBT on long-term oncological outcomes [progression-free survival (PFS) and overall survival (OS)] were assessed by using multivariate analysis. RESULTS: Overall, 74% of the patients were transfused with a median of 2 PRBCs (range 0-37). Transfusion level correlated with operative time, surgical extent (as measured by the peritoneal carcinomatosis index), and age. Postoperatively, patients with major transfusion (> 6 PRBCs) had increased mortality rate (11.1%, p = 0.01) and length of hospital stay (31.2 ± 16.8 days, p = 0.01) compared with other levels of RBT. RBT was dose-dependently associated with oncological outcomes in both DMPM and PMP for both PFS [hazard ratio (HR) = 1.40, 95% confidence interval (CI) 1.12-1.74, p = 0.003; HR = 1.44, 95% CI 1.15-1.81, p = 0.001, respectively] and OS (HR = 1.57, 95% CI 1.21-2.03, p = 0.001; HR = 1.43, 95% CI 1.15-1.90, p = 0.01, respectively). CONCLUSIONS: Our data show a dose-dependent relationship between RBT and oncological outcomes. Further research to develop transfusion sparing protocols is needed in this extensive surgical procedure.