Search

Aim: Pseudomyxoma peritonei (PMP) is an uncommon pathology, and its rarity causes a lack of scientific evidence, precluding the design of a prospective trial. A diagnostic and therapeutic algorithm (DTA) is necessary in order to standardize the disease treatment while balancing optimal patient management and the correct use of resources. The Consensus of the Italian Society of Surgical Oncology (SICO) Oncoteam aims at defining a diagnostic and therapeutic pathway for PMP and appendiceal primary tumors applicable in Italian healthcare. Method: The consensus panel included 10 delegated representatives of oncological referral centers for Peritoneal Surface Malignancies (PSM) affiliated to the SICO PSM Oncoteam. A list of statements regarding the DTA of patients with PMP was prepared according to recommendations based on the review of the literature and expert opinion. Results: A consensus was obtained on 33 of the 34 statements linked to the DTA; two flowcharts regarding the management of primary appendiceal cancer and peritoneal disease were approved. Conclusion: Currently, consensus has been reached on pathological classification, preoperative evaluation, cytoreductive surgery technical detail, and systemic treatment; some controversies still exist regarding the exclusion criteria for HIPEC treatment. A shared Italian model of DTA is an essential tool to ensure the appropriateness and equity of treatment for these patients.

Diffuse malignant peritoneal mesothelioma (DMPM) is a rare form of mesothelioma that carries a very poor prognosis. The 5-year overall survival is about 20% (±5.9). Survival is optimal for patients suitable for cytoreductive surgery (CRS) with Hyperthermic Intraperitoneal Chemotherapy (HIPEC), with a median OS ranging from 34 to 92 months. However, selecting patients for surgery remains a complex task and requires a careful preoperative workup, rational analysis of prognostic profiles, and risk prediction models. Systemic chemotherapy could be offered: (1) in the adjuvant setting for high-risk patients; (2) for patients not eligible for CRS; and (3) for those with recurrent disease. It mainly includes the combination of Platin compound with Pemetrexed or immunotherapy. The biology of DMPM is still largely unknown. However, progress has been made on some fronts, such as telomere maintenance mechanisms, deregulation of apoptosis, tyrosine kinase pathways, and mutation of BRCA1-associated protein 1 (BAP1). Future perspectives should include translational research to improve our understanding of the disease biology to identify druggable targets. We should also clear the role of immune checkpoint inhibitors and investigate new locoregional technologies, such as pressurized intraperitoneal aerosol chemotherapy (PIPAC) or normothermic intraperitoneal chemotherapy (NIPEC).

Background gastric cancer patients frequently develop peritoneal metastases (PM) with a poor long-term prognosis. A solid body of evidence underlines the beneficial role of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) on survival, but to date, there is a lack of consensus regarding the optimal strategy in the treatment of locally advanced primary tumors with or without peritoneal metastasis. The present meta-analysis aims to assess the impact of CRS + HIPEC on survival analyzing the results of randomized studies only. Methods A systematic review of articles was conducted according to PRISMA guidelines. Twelve studies were included in qualitative and quantitative analysis. Results A survival benefit for patients treated with CRS + HIPEC at all time points was highlighted. However, difference in survival was significant at all time points for patients treated for prophylaxis of PM, but no difference was found when considering resection with a curative intent. The 1, 2, 3 and 5-year survival rates (SR) for patients undergoing CRS + HIPEC were 86.9%, 70.5%, 63.7% and 55.7% respectively. CRS + HIPEC for the treatment rather than prophylaxis of PM was the only predictor of a reduced 3y SR. Conclusions CRS + HIPEC may lead to improved prognosis for patients suffering from locally advanced gastric cancer in both prophylactic and curative settings. However, due to far from negligible postoperative morbidity and mortality rates, a strict patient selection is crucial to achieve the best results. The presence of extraperitoneal disease strongly limits the indication of this kind of surgery.

The advent of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) has improved survival in patients with peritoneal surface malignancies. Not surprisingly, there is now a growing interest on the possible means to preserve fertility to ensure future childbearing. In this study, we report on five women with peritoneal surface malignancies who performed ovarian hyper-stimulation and oocytes cryostorage prior to undergo CRS and HIPEC. The presence of the disease complicated follicular growth monitoring but the oocytes retrievals could be always performed and were uneventful. At last follow-up, all women were alive and disease-free. None has yet returned to thaw her oocytes. Overall, these cases suggest that oocytes cryopreservation before CRS and HIPEC should be considered.

Introduction: The PRODIGE 7-trial investigated the additional value of Hyperthermic Intraperitoneal Chemotherapy (HIPEC) to cytoreductive surgery (CRS) for patients with colorectal peritoneal metastases (CPM). The results of PRODIGE 7 were presented at the 2018 ASCO meeting showing that 30 min oxaliplatin-based HIPEC did not improve overall survival. The current study investigated the impact of PRODIGE 7 on the worldwide practice of CRS and HIPEC. Materials and methods: CRS-HIPEC experts from 19 countries were invited through the Peritoneal Surface Oncology Group International (PSOGI) to complete an online survey concerning the current CRS-HIPEC practice in their hospital and country, and were asked to appraise the effect of PRODIGE 7. Results: The survey was completed by 18/19 experts. Although their personal opinions of CRS-HIPEC were barely influenced by PRODIGE 7, they reported a substantial impact on daily practice. This included a switch towards Mitomycin-C based HIPEC-regimens and prolongation of HIPEC perfusion time, a reduction in the number of referrals from non-HIPEC centers, a reduction in national consensus, the removal of HIPEC from national guidelines, and a reduced reimbursement rate. Conclusion: The PRODIGE 7 has had a major impact on the practice of CRS-HIPEC for CPM worldwide. HIPEC remains an attractive option with potential for control and eradication of disease and further studies into the optimal HIPEC-regimen are urgently needed. Meanwhile, given the complexity of the treatment of patients with CPM, and the proven benefits of optimal CRS, referral of patients with potentially resectable CPM to expert centers is recommended whilst the precise role of HIPEC is further evaluated. (c) 2021 Published by Elsevier Ltd.

Background: Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy may significantly improve survival for selected patients with peritoneal surface malignancies, but it has always been criticized due to the high incidence of postoperative morbidity and mortality. Methods: Data were collected from nine Italian centers with peritoneal surface malignancies expertise within a collaborative group of the Italian Society of Surgical Oncology. Complications and mortality rates were recorded, and multivariate Cox analysis was used to identify risk factors. Results: The study included 2576 patients. The procedure was mostly performed for ovarian (27.4%) and colon cancer (22.4%). The median peritoneal cancer index was 13. Overall postoperative morbidity and mortality rates were 34% and 1.6%. A total of 232 (9%) patients required surgical reoperation. Multivariate regression logistic analysis identified the type of perfusion (p ≤ 0.0001), body mass index (p ≤ 0.0001), number of resections (p ≤ 0.0001) and colorectal resections (p ≤ 0.0001) as the strongest predictors of complications, whereas the number of resections (p ≤ 0.0001) and age (p = 0.01) were the strongest predictors of mortality. Conclusions: Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy is a valuable option of treatment for selected patients with peritoneal carcinomatosis providing low postoperative morbidity and mortality rates, if performed in high-volume specialized centers.

Peritoneal metastases (PM) are one of the most common routes of dissemination for colorectal cancer (CRC) and remain a lethal disease with a poor prognosis. The compositional, mechanical and structural properties of the extracellular matrix (ECM) play an important role in cancer development; studying how these properties change during the progression of the disease is crucial to understand CRC-PM development.The elastic properties of ECMs derived from human samples of normal and neoplastic PM in different pathological conditions were studied by atomic force microscopy (AFM); results were correlated to patients’ clinical data and to the expression of ECM components related to metastatic spread.Our results show that PM progression is accompanied by stiffening of ECM as a common feature; spatially resolved mechanical analysis highlighted significant spatial heterogeneity of the elastic properties of both normal and neoplastic ECMs, which show significant overlap in the two conditions. On the micrometre scale, ECMs that are considered normal according to the pathological classification possess stiffer spatial domains, which are typically associated with cancer associated fibroblasts (CAF) activity and tumour development in neoplastic matrices; on the other hand, softer regions are found in neoplastic ECMs on the same scales. Our results support the hypothesis that local changes (stiffening) in the normal ECM can create the ground for growth and spread from the tumour of invading metastatic cells.Mechanical changes correlate well with the presence of CAF and an increase in collagen deposition, which are well known markers of cancer progression. Furthermore, we have found correlations between the mechanical properties of the ECM and patients’ clinical data like age, sex, presence of mutations inBRAFandKRASgenes and tumour grade.Overall, our findings suggest that the mechanical phenotyping of the PM-ECM has the potential for predicting tumour development.

Aims To evaluate the effects of high intra-abdominal pressure (IAP) during hyperthermic intraperitoneal chemotherapy (HIPEC) on cisplatin uptake by residual tumor and normal tissues, pharmacokinetics, and short-term surgical outcomes. Patients & methods Patients with peritoneal metastasis from colorectal cancer or pseudomyxoma peritonei were randomized to closed-abdomen HIPEC with low-IAP or high-IAP, after complete cytoreduction. High-IAP was obtained increasing the volume of perfusate maintaining constant the cisplatin concentration (42 mg/L). We determined the Platinum concentration using an Inductive Coupled Plasma Mass Spectrometry System. Randomization was stratified according to tumor type. To consider the multiple sampling in the three tissues types of interest, we performed linear mixed models to assess the differences of cisplatin concentration between study arms. We also compared AUC perfusate/plasma ratios (Wilcoxon-Mann-Whitney) and perioperative severe complication rates (chi-square) between study arms. Results 38 cases were randomly assigned to IAP arms (n = 19 each). Median IAPs were 19 mmHg and 11 mmHg in the high and low arms, respectively. Cisplatin concentrations did not differ in the tumor residual tissues and in the muscular fascia [22.8 ng/mg (SD: 25.5) vs. 15.9 ng/mg (SD: 13.3), p = 0.181] and [50.3 ng/mg (SD: 40.1) vs. 42.0 ng/mg (SD: 38.3), p = 0.426, respectively], whereas in the mesenteric peritoneum it did [5.4 ng/mg (SD: 7.82) vs. 2.7 ng/mg (SD: 2.9), p = 0.048]. Pharmacokinetic advantage did not differ between the two arms. High-IAP did not increase perioperative severe complications rate (NCI-CTCAE.v3). Conclusions high-IAP HIPEC increases cisplatin distribution in the mesenteric peritoneum, is safe, and could be considered to obtain microscopic cytoreduction.

Introduction: Surgical management of patients with multiple metastases from mucinous rectal carcinoma is feasible. Case description: We present a case of a 66-year-old woman with a late onset of peritoneal and coccygeal metastasis from a mucinous rectal carcinoma treated with cytoreductive surgery. After 30 months from rectal resection, the patient underwent exploratory laparotomy with resection of all tumor localizations by means of pelvic peritonectomy, complete supracolic omentectomy, jejuneal resection, appendectomy, and excision of the mobile part of the coccyx. Conclusion: This report aims to point out the atypical late-onset recurrence presentation and management of a mucinous carcinoma of the rectum.

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. 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. 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). 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.

The aim of this study was to assess the performance of fluorescence in situ hybridization (FISH) in identifying the copy number profiles of the three key peritoneal mesothelioma tumor suppressor genes BAP1, CDKN2A, and NF2, with particular emphasis on minute homozygous deletions, a copy number abnormality recently unveiled at the 3p21 (BAP1) chromosomal region using high-throughput methods. FISH was performed on 75 formalin-fixed-paraffin-embedded peritoneal mesotheliomas and recognized two types of monoallelic loss (monosomy, and hemizygous deletion) and two types of biallelic loss (canonical homozygous deletion with a complete loss of FISH signal and homozygous deletion with diminished signal). Diminished FISH signals revealed deletions occurring within the genomic region covered by the gene-specific probe and affected all three tumor suppressors. BAP1 homozygous deletions with diminished signal outnumbered canonical homozygous deletions (13 vs 3): conversely, canonical homozygous deletions were prevalent for CDKN2A (2 vs 14). Diminished signal homozygous deletion was the only pattern of biallelic loss observed for NF2 (2 cases). Hemizygous deletion mainly affected BAP1 (21 vs 6), while monosomy was prevalent for CDKN2A (14 vs 7) and particularly for NF2 where it accounts for all monoallelic losses. FISH/immunohistochemistry (BAP1, CDKN2A, and MTAP) correlation showed that all homozygous deletions, including those with diminished signals, resulted in a null BAP1 and CDKN2A immunophenotype but only canonical CDKN2A homozygous deletions resulted in MTAP loss of expression. BAP1 hemizygous deletion, but not monosomy, was also invariably associated with loss of protein expression whereas neither type of CDKN2A monoallelic loss correlated with p16 or MTAP immunohistochemistry. Array comparative genomic hybridization performed on a spontaneously emerging peritoneal mesothelioma cell line provided support for the interpretation of the FISH patterns and allowed us to extend the number of chromatin remodeling factors involved in mesothelioma to SETD7 and PCGF5, two previously unreported genes.

Diffuse malignant peritoneal mesothelioma (DMPM) is a rare and rapidly lethal tumor, poorly responsive to conventional treatments. In this regards, the identification of molecular alterations underlying DMPM onset and progression might be exploited to develop novel therapeutic strategies. Here, we focused on miR-550a-3p, which we found downregulated in 45 DMPM clinical samples compared to normal tissues and whose expression levels were associated with patient outcome. Through a gain-of-function approach using miRNA mimics in 3 DMPM cell lines, we demonstrated the tumor-suppressive role of miR-550a-3p. Specifically, miRNA ectopic expression impaired cell proliferation and invasiveness, enhanced the apoptotic response, and reduced the growth of DMPM xenografts in mice. Antiproliferative and proapoptotic effects were also observed in prostate and ovarian cancer cell lines following miR-550a-3p ectopic expression. miR-550a-3p effects were mediated, at least in part, by the direct inhibition of HSP90AA1 and the consequent downregulation of its target proteins, the levels of which were rescued upon disruption of miRNA-HSP90AA1 mRNA pairing, partially abrogating miR-550a-3p-induced cellular effects. Our results show that miR-550a-3p reconstitution affects several tumor traits, thus suggesting this approach as a potential novel therapeutic strategy for DMPM.

The metastasizing potential of pseudomyxoma peritonei (PMP) is largely unknown. We assessed incidence, impact on prognosis, treatments, and outcomes of systemic metastases after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC).A prospective database of 327 patients undergoing CRS/HIPEC for PMP of appendiceal origin was reviewed. PMP was graded according to the Peritoneal Surface Oncology Group International (PSOGI) classification. Haematogenous metastases, and non-regional lymph-node involvement were considered as systemic metastases.After a median follow-up of 74.8 months (95% confidence interval [CI] = 68.0-94.8), systemic metastases occurred in 21 patients. Eleven patients were affected by low-grade PMP, and ten by high-grade PMP. Metastatic disease involved the lung (n = 12), bone (n = 1), liver (n = 4), distant nodes (n = 3), both lung and distant nodes (n = 1). Systemic metastases independently correlated with PSOGI histological subtypes (P = 0.001), and incomplete cytoreduction (P = 0.026). Median OS was 139.0 months (95%CI = 56.6-161.9) for patients who experienced systemic metastases, and 213.8 months (95%CI = 148.7-not reached) for those who did not (P = 0.159). Eight of eleven patients who had curative-intent surgery are presently alive at a median of 52.5 months (range 2.0-112.7). Seven are disease-free at a median of 27.4 months (range 2.0-110.4). At multivariate analysis, PSOGI histological subtypes (P = 0.001), completeness of cytoreduction (P = 0.001), and preoperative systemic chemotherapy (P = 0.020) correlated with poorer survival. Systemic metastases did not (P = 0.861).After CRS/HIPEC, systemic metastases occur in a small but clinically relevant number of patients, and the risk increases with incomplete cytoreduction and aggressive histology. In selected patients, surgical resection of metastatic disease can result in long survival.

Peritoneal metastases (PM) from colorectal cancer (CRC) are associated with poor survival. The extracellular matrix (ECM) plays a fundamental role in modulating the homing of CRC metastases to the peritoneum. The mechanisms underlying the interactions between metastatic cells and the ECM, however, remain poorly understood and the number of in vitro models available for the study of the peritoneal metastatic process is limited. Here, we show that decellularized ECM of the peritoneal cavity allows the growth of organoids obtained from PM, favoring the development of three-dimensional nodules that maintain the characteristics of in vivo PM. Organoids preferentially grow on scaffolds obtained from neoplastic peritoneum, which are characterized by greater stiffness than normal scaffolds. A gene expression analysis of organoids grown on different substrates reflected faithfully the clinical and biological characteristics of the organoids. An impact of the ECM on the response to standard chemotherapy treatment for PM was also observed.SignificanceEvidence of the value of ex vivo 3D models obtained by combining patient-derived extracellular matrices depleted of cellular components and organoids to mimic the metastatic niche, to be used as a tool to develop new therapeutic strategies in a biologically relevant context, to personalize treatments and increase their efficacy.

IntroductionDespite optimal patient selection and surgical effort, recurrence is seen in over 70% of patients undergoing cytoreductive surgery (CRS) for peritoneal metastases (PM). Apart from the Peritoneal Cancer Index (PCI), completeness of cytoreduction and tumour grade, there are other factors like disease distribution in the peritoneal cavity, pathological response to systemic chemotherapy (SC), lymph node metastases and morphology of PM which may have prognostic value. One reason for the underutilisation of these factors is that they are known only after surgery. Identifying clinical predictors, specifically radiological predictors, could lead to better utilisation of these factors in clinical decision making and the extent of peritoneal resection performed for different tumours. This study aims to study these factors, their impact on survival and identify clinical and radiological predictors.Methods and analysisThere is no therapeutic intervention in the study. All patients with biopsy-proven PM from colorectal, appendiceal, gastric and ovarian cancer and peritoneal mesothelioma undergoing CRS will be included. The demographic, clinical, radiological, surgical and pathological details will be collected according to a prespecified format that includes details regarding distribution of disease, morphology of PM, regional node involvement and pathological response to SC. In addition to the absolute value of PCI, the structures bearing the largest tumour nodules and a description of the morphology in each region will be recorded. A correlation between the surgical, radiological and pathological findings will be performed and the impact of these potential prognostic factors on progression-free and overall survival determined. The practices pertaining to radiological and pathological reporting at different centres will be studied.Ethics and disseminationThe study protocol has been approved by the Zydus Hospital ethics committee (27 July, 2020) and Lyon-Sud ethics committee (A15-128).Trial registration numberCTRI/2020/09/027709; Pre-results.

Malignant mesothelioma is a disease affecting serosal surfaces derived from the mesothelium comprising the pleura, peritoneum, pericardium, and tunica vaginalis testis [...]

Introduction Serous papillary peritoneal carcinoma (SPPC) is a rare clinical entity. Based on the understanding of the pattern of spread, its multifocality, polyclonality and the high frequency of diffuse, widespread peritoneal metastasis, a robust rationale for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for SPPC exists. Herein we report the clinical outcomes of SPPC patients treated with neoadjuvant systemic chemotherapy (NACT) followed by CRS including total parietal peritonectomy and HIPEC. Methods Clinico-pathological data of 22 patients of serous papillary peritoneal carcinoma (SPPC) was retrospectively analyzed from a prospectively maintained database from June 2000 to July 2017. Patients were treated with CRS, total parietal peritonectomy and HIPEC with cisplatin (42 mg/L of perfusate) and doxorubicin (15 mg/L of perfusate) after NACT. Survival curves were calculated from the date of surgery. Results 22 patients underwent CRS, total parietal peritonectomy and HIPEC. The median age was 62 years (Range 47–72). On histological evaluation, 18/30 (60%) parietal peritonectomy specimens showed microscopic disease, when no disease was evident macroscopically at surgical exploration. Grade III-IV surgical complications were recorded in 4/22 (18%) patients. There was no postoperative mortality. At a median follow up of 12 months, the five-year overall survival (OS) was 64.9%. The median OS was not reached. Median progression-free survival was 32.9 months and progression-free survival at 5 years was 33.2%. Conclusion CRS with total peritonectomy + HIPEC after NACT, presents as a promising treatment modality for SPPC, and could be associated with good survival results in patients with SPPC.

Background Well differentiated papillary peritoneal mesothelioma (WDPPM) is a rare variant of mesothelioma which affects mainly women in the reproductive age. The disease may present multifocally and recur after primary resection. Our aim was to describe the outcomes of cytoreduction (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in this disease. Methods Patients with histological diagnosis of WDPPM were retrieved from the PSOGI registry. Demographical and clinical data were extracted as well as outcomes data (overall survival (OS) and recurrence free survival (RFS)). Results We analyzed 45 patients for whom complete data was available. The majority of patients were women (n = 33, 73%) with a median age of 44 years. Preoperative chemotherapy (CT) was administered in 8 patients (18%). Median peritoneal carcinomatosis index was 9 (1–30), and complete cytoreduction was achieved in 69% of patients. There was one case (2%) of postoperative mortality, and 24% rate of severe morbidity. Overall, there were 4 deaths and 5 years OS was 80%. 8 patients (18%) had disease recurrence, all within 5 years from operation. On univariate analysis preoperative CT, high PCI and severe morbidity were associated with reduced RFS. On multivariate analysis, only preoperative CT (HR = 32.6, 95% CI: 2.39–446.2, p = 0.009) and high PCI (HR = 21.7, 95% CI: 1.11–425.7, p = 0.04) remained significant risk factors. Conclusions WDPPM can be a lethal disease with substantial recurrence even after aggressive treatment. Patients presenting with extensive disease or disease recurrence after surgical excision are at increased risk for relapse. CRS + HIPEC can be safely applied to WDPPM in specialized centers.

IntroductionDespite optimal patient selection and surgical effort, recurrence is seen in over 70% of patients undergoing cytoreductive surgery(CRS) for peritoneal metastases (PM). Apart from the peritoneal cancer index(PCI), completeness of cytoreduction and tumor grade, there are other factors like disease distribution in the peritoneal cavity, pathological response to systemic chemotherapy(SC), lymph node metastases and morphology of PM which may have prognostic value. One reason for the underutilization of these factors is that they are known only after surgery. Identifying clinical predictors, specifically radiological predictors, could lead to better utilization of these factors in clinical decision making and the extent of peritoneal resection performed for different tumors. This study aims to study these factors, their impact on survival and identify clinical and radiological predictors. Methods and analysisThere is no therapeutic intervention in the study. All patients with biopsy proven PM from colorectal, appendiceal, gastric and ovarian cancer and peritoneal mesothelioma undergoing CRS will be included. The demographic, clinical, radiological, surgical and pathological details will be collected according to a pre-specified format that includes details regarding distribution of disease, morphology of PM, regional node involvement and pathological response to SC. In addition to the absolute value of PCI, the structures bearing the largest tumor nodules and a description of the morphology in each region will be recorded. A correlation between the surgical, radiological and pathological findings will be performed and the impact of these potential prognostic factors on progression-free and overall survival determined. The practices pertaining to radiological and pathological reporting at different centers will be studied. Ethics and disseminationThe study protocol has been approved by the Zydus Hospital ethics committee (27th July, 2020) and Lyon-sud ethics committee (A15-128). It is registered with the clinical trials registry of India (CTRI/2020/09/027709).The results will be published in peer-reviewed scientific journals.Strength and limitationsA prospective correlation between the radiological, surgical and pathological findings in patients undergoing CRS will be performed which has not been done before.Being prospective in nature it will also enable us to evaluate the impact of the current treatment practices on the clinical end-pointsThere is fixed protocol for radiological and pathological evaluation for which there are no specific guidelinesThe data collection format will capture all the relevant data but this may affect compliance.Despite the large sample size planned for each primary site, the heterogeneity of treatment protocols may be a limiting factor while evaluating the impact on survival.

The development of multimodality treatment, including cytoreductive surgery (CRS) with heated intraperitoneal chemotherapy (HIPEC), has led to promising results in selected patients with peritoneal disease of gastric origin. The aim of this study was to investigate the short- and long-term outcomes of CRS/HIPEC in the treatment of synchronous peritoneal metastasis in gastric cancer.The Italian Peritoneal Surface Malignancies Oncoteam-S.I.C.O. retrospective registry included patients with synchronous peritoneal malignancy from gastric cancer submitted to gastrectomy with CRS and HIPEC between 2005 and 2018 from 11 high-volume, specialized centers.A total of 91 patients with a median age of 58 years (range 26-75) were enrolled. The median overall survival (OS) time for the whole group of patients was 20.2 months (95% confidence interval [CI] 11.8-28.5] and the median recurrence-free survival (RFS) was 7.3 months (95% CI 4-10.6). The completeness of cytoreduction score (CCS) of 0 and Peritoneal Cancer Index (PCI) score of ≤ 6 groups showed a significantly better long-term survival (median OS 40.7 and 44.3 months, respectively) compared with the incomplete resected groups (median OS 10.7 months, p = 0.003) and PCI score of6 group (median OS 13.4 months, p = 0.005). A significant difference was observed in the survival rate according to neoadjuvant treatment (untreated patients: 10.7 months, 95% CI 5.1-16.2; treated patients: 35.3 months, 95% CI 2.8-67.8; p = 0.022).In referral centers, CRS and HIPEC after neoadjuvant treatment significantly improved survival in selected patients. Patients with a PCI score ≤ 6, complete cytoreduction, negative nodal involvements, and negative cytology had encouraging results, showing a clinically meaningful survival.

Peritoneal mesothelioma is a rare disease with an incidence of approx. 0.2–3 per million in industrialized countries and originates from mesothelial cells of the peritoneum. The treatment of this malignant disease depends on the patient condition and aggressiveness of the tumor, which corresponds to three different histopathologic subtypes: epithelioid, sarcomatoid, and biphasic. The prognosis of the epithelioid subtype of peritoneal mesothelioma is considerably better compared with sarcomatoid or biphasic, which have a poor prognosis. Cytoreductive surgery in combination with hyperthermic intraperitoneal chemotherapy has been established as an effective treatment option for selected patients, resulting in a median overall survival of more than 50 months compared with 1 or 2 years in patients treated with palliative chemotherapy. This chapter explores the epidemiologic background and highlights the diagnostic aspects and treatment options for patients with peritoneal mesothelioma.

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) leads to prolonged survival for selected patients with colorectal (CRC) peritoneal metastases (PM). This study aimed to analyze the prognostic role of micro-satellite (MS) status and RAS/RAF mutations for patients treated with CRS. Data were collected from 13 Italian centers with PM expertise within a collaborative group of the Italian Society of Surgical Oncology. Clinical and pathologic variables and KRAS/NRAS/BRAF mutational and MS status were correlated with overall survival (OS) and disease-free survival (DFS). The study enrolled 437 patients treated with CRS-HIPEC. The median OS was 42.3 months [95% confidence interval (CI), 33.4–51.2 months], and the median DFS was 13.6 months (95% CI, 12.3–14.9 months). The local (peritoneal) DFS was 20.5 months (95% CI, 16.4–24.6 months). In addition to the known clinical factors, KRAS mutations (p = 0.005), BRAF mutations (p = 0.01), and MS status (p = 0.04) were related to survival. The KRAS- and BRAF-mutated patients had a shorter survival than the wild-type (WT) patients (5-year OS, 29.4% and 26.8% vs 51.5%, respectively). The patients with micro-satellite instability (MSI) had a longer survival than the patients with micro-satellite stability (MSS) (5-year OS, 58.3% vs 36.7%). The MSI/WT patients had the best prognosis. The MSS/WT and MSI/mutated patients had similar survivals, whereas the MSS/mutated patients showed the worst prognosis (5-year OS, 70.6%, 48.1%, 23.4%; p = 0.0001). In the multivariable analysis, OS was related to the Peritoneal Cancer Index [hazard ratio (HR), 1.05 per point], completeness of cytoreduction (CC) score (HR, 2.8), N status (HR, 1.6), signet-ring (HR, 2.4), MSI/WT (HR, 0.5), and MSS/WT-MSI/mutation (HR, 0.4). Similar results were obtained for DFS. For patients affected by CRC-PM who are eligible for CRS, clinical and pathologic criteria need to be integrated with molecular features (KRAS/BRAF mutation). Micro-satellite status should be strongly considered because MSI confers a survival advantage over MSS, even for mutated patients.

BackgroundThe development of multimodality treatment, including cytoreductive surgery (CRS) with heated intraperitoneal chemotherapy (HIPEC), has led to promising results in selected patients with peritoneal disease of gastric origin. The aim of this study was to investigate the short- and long-term outcomes of CRS/HIPEC in the treatment of synchronous peritoneal metastasis in gastric cancer.MethodsThe Italian Peritoneal Surface Malignancies Oncoteam—S.I.C.O. retrospective registry included patients with synchronous peritoneal malignancy from gastric cancer submitted to gastrectomy with CRS and HIPEC between 2005 and 2018 from 11 high-volume, specialized centers.ResultsA total of 91 patients with a median age of 58 years (range 26–75) were enrolled. The median overall survival (OS) time for the whole group of patients was 20.2 months (95% confidence interval [CI] 11.8–28.5] and the median recurrence-free survival (RFS) was 7.3 months (95% CI 4–10.6). The completeness of cytoreduction score (CCS) of 0 and Peritoneal Cancer Index (PCI) score of ≤ 6 groups showed a significantly better long-term survival (median OS 40.7 and 44.3 months, respectively) compared with the incomplete resected groups (median OS 10.7 months,p = 0.003) and PCI score of > 6 group (median OS 13.4 months,p = 0.005). A significant difference was observed in the survival rate according to neoadjuvant treatment (untreated patients: 10.7 months, 95% CI 5.1–16.2; treated patients: 35.3 months, 95% CI 2.8–67.8;p = 0.022).ConclusionsIn referral centers, CRS and HIPEC after neoadjuvant treatment significantly improved survival in selected patients. Patients with a PCI score ≤ 6, complete cytoreduction, negative nodal involvements, and negative cytology had encouraging results, showing a clinically meaningful survival.

Background Expression of proton-coupled folate transporter (PCFT) is associated with survival of mesothelioma patients treated with pemetrexed, and is reduced by hypoxia, prompting studies to elucidate their correlation. Methods Modulation of glycolytic gene expression was evaluated by PCR arrays in tumour cells and primary cultures growing under hypoxia, in spheroids and after PCFT silencing. Inhibitors of lactate dehydrogenase (LDH-A) were tested in vitro and in vivo. LDH-A expression was determined in tissue microarrays of radically resected malignant pleural mesothelioma (MPM, N = 33) and diffuse peritoneal mesothelioma (DMPM, N = 56) patients. Results Overexpression of hypoxia marker CAIX was associated with low PCFT expression and decreased MPM cell growth inhibition by pemetrexed. Through integration of PCR arrays in hypoxic cells and spheroids and following PCFT silencing, we identified the upregulation of LDH-A, which correlated with shorter survival of MPM and DMPM patients. Novel LDH-A inhibitors enhanced spheroid disintegration and displayed synergistic effects with pemetrexed in MPM and gemcitabine in DMPM cells. Studies with bioluminescent hypoxic orthotopic and subcutaneous DMPM athymic-mice models revealed the marked antitumour activity of the LDH-A inhibitor NHI-Glc-2, alone or combined with gemcitabine. Conclusions This study provides novel insights into hypoxia/PCFT-dependent chemoresistance, unravelling the potential prognostic value of LDH-A, and demonstrating the preclinical activity of LDH-A inhibitors.

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. 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). 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

Background Appendiceal non-mucinous neoplasms (AnMN) are rare and poorly understood malignancies with no standard treatment. Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) is largely used to treat peritoneal disseminations from appendiceal mucinous neoplasms (AMN), but its role with AnMN is unclear. Methods A prospective database of 315 patients with advanced appendiceal primaries undergoing CRS/HIPEC during 1996-2020 was reviewed. Baseline characteristics, operative and long-term outcomes of AnMN were compared with those of AMN. AMN were categorized according to PSOGI classification into high-grade, low-grade, and acellular mucin (AC), based on peritoneal disease histology. Results Twenty-three patients (7.3%) with goblet cell carcinoma (GCC; n = 9), intestinal-type adenocarcinoma (ITAC; n = 12), and mixed adeno-neuroendocrine carcinoma (MANEC; n = 2) were identified. AnMN patients were more likely to be males (P = 0.006), have preoperative systemic chemotherapy (P = 0.001), grossly incomplete CRS (P = 0.001), and nodal metastases (P = 0.001), but not systemic relapse after CRS/HIPEC (P = 0.133). Median follow-up was 25.1 months (range 0.8-77.3) for AnMN, and 80.9 months (range 0.1-279.2) for AMN. Median overall survival was 24.0 months for AnMN, 66.2 months for high-grade AMN (P = 0.015), 160.0 months for low-grade ANM (P = 0.001), and not reached for AC (P = 0.001). Among AnMN patients, median survival was 23.4 months for GCC, 38.7 months for ITAC, 20.3 months for MANEC (P = 0.855). In the overall series, histological subtype (P = 0.001), incomplete cytoreduction (P = 0.001), and positive lymph-nodes (P = 0.003) correlated with poorer survival at multivariate analysis. Conclusions AnMN share with AMN a predominant local-regional dissemination pattern, but prognosis after CRS/HIPEC is worse. This strategy needs to be carefully considered for AnMN.

Aim the surgical workup for colorectal cancer peritoneal metastases (CRCPM) is complex and should be managed in specialized centers. Diagnostic and therapeutic algorithms (DTA) have been proposed to balance optimal patients management and correct use of resources. Aim of this study was to establish a consensus on DTA for CRCPM patients in Italy. Method a panel of 18 delegated members of centers afferent to Peritoneal Surface Malignancies Onco-team of the Italian Society of Surgical Oncology was established. A list of statements regarding the DTA of patients with CRCPM was prepared according to different activities and decision-making nodes with a defined entry and exit point. Consensus was obtained through RAND UCLA methodology. Results two different DTA were defined and approved according to the modality of presentation of CRCPM (synchronous and metachronous). A consensus was also obtained on 17 of the 19 statements related to DTA. Conclusion a shared model of DTA is now available for healthcare providers to monitor appropriateness in diagnosis and treatment of patients with isolated peritoneal metastases from CRC.

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 (&gt, 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 &gt, 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.

Background Multicystic peritoneal mesothelioma (MCPM) is an extremely rare disease with 40–50% rate of recurrence after surgical debulking. Due to the recurrent nature of the disease, the option of cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy (HIPEC) was offered for this condition. In the present study we aimed to describe the outcomes of this strategy in a single center cohort. Methods We retrospectively reviewed a prospectively collected database of all patients with MCPM that underwent the combined procedure in our center. Clinical presentation, operative procedures and outcomes were reviewed. Results Between August 1997 and October 2017, 19 patients with MCPM underwent 20 cytoreduction and HIPEC procedures in our center. The majority of the patients were females (n = 17, 89%), and mean age was 42, as reported in other series. Disease extent, as measured by mean peritoneal carcinomatosis index (PCI) was 15.5 ± 9.9 and total number of procedures performed 6.7 ± 2.6. Major complications occurred in 3 (15%) patients, with no perioperative mortality. After a median of follow-up of 69 months (range 4–220) all patients were alive and 4 patients had recurrence (21%). Patients with high PCI (defined by median PCI) had shorter recurrence free survival (RFS) than patient with low PCI (mean RFS = 106.4 ± 6.6 for high PCI vs. 125.6 ± 34.1 for low PCI, p = 0.03). Conclusion Cytoreduction and HIPEC offer low recurrence rate and prolonged mean RFS for patients with MCPM. The combined procedure can be offered with acceptable morbidity in specialized centers.

The differential diagnosis between diffuse malignant peritoneal mesothelioma (DMPM) and other peritoneal surface malignancies (PSM) is still challenging. Serum mesothelin and osteopontin are increasingly used as markers of pleural mesothelioma, but their role in DMPM is unclear. We assessed the diagnostic and prognostic values of mesothelin, osteopontin, CEA, CA19.9, CA125, and CA15.3 in DMPM patients.Markers were dosed before cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) by enzyme-linked immunosorbent assay (ELISA) in 30 DMPM patients and 14 controls with other PSMs. Receiver-operating characteristics (ROC) curve were plotted. The performance of each marker was assessed by the area under the ROC curve (AUC-ROC).Mean mesothelin levels were 7.84 ng/dl (SD = 5.14) in DMPM group and 3.00 ng/dl (SD = 1.25) in controls (P = 0.001). Mean CEA levels were 5.3 ng/dl (SD = 4.7), and 61.96 ng/dl (SD = 112.5) in the two groups (P = 0.008). No statistical difference was seen for osteopontin (P = 0.738), CA19.9 (P = 0.081), CA125 (P = 0.600), and CA15.3 (P = 0.365). AUC-ROC was 0.836 for CA19.9, 0.812 for mesothelin, 0.793 for CEA, and lower for CA125 (0.652), osteopontin (0.531), and CA15.3 (0.481). Using diagnostic cut-offs selected by ROC methodology, sensitivity, specificity, positive and negative predictive values were 70.0%, 100.0%, 100.0%, and 60.9% for mesothelin5.21 ng/dl, and 90.0%, 85.7%, 93.1%, and 80.0% for CA19.9 8.8 U/dl. At multivariate analysis, osteopontin correlated with survival (hazard rate 6.46; 95%CI 1.81-23.05; P = 0.004).When assessing PSMs of unknown origin, elevated mesothelin with low CA19.9 may increase the suspicion index for DMPM. Ospeopontin warrants further investigations as a prognostic marker for DMPM.