The Delphi and GRADE methodology used in the PSOGI 2018 consensus statement on Pseudomyxoma Peritonei and Peritoneal Mesothelioma

Pseudomyxoma Peritonei (PMP) and Peritoneal Mesothelioma (PM) are both rare peritoneal malignancies. Currently, affected patients may be treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy offering long-term survival or even cure in selected patients. However, many issues regarding the optimal treatment strategy are currently under debate. To aid physicians involved in the treatment of these patients in clinical decision making, the PSOGI executive committee proposed to create a consensus statement on PMP and PM. This manuscript describes the methodology of the consensus process. The Delphi technique is a reliable method for attaining consensus on a topic that lacks scientific evidence through multiple voting rounds which feeds back responses to the participants in between rounds. The GRADE system provides a structured framework for presenting and grading the available evidence. Separate questionnaires were created for PMP and PM and sent during two voting rounds to 80 and 38 experts, respectively. A consensus threshold of 51.0% was chosen. After the second round, consensus was reached on 92.9%–100.0% of the questions. The results were presented and discussed in the plenary session at the PSOGI 2018 international meeting in Paris. A third round for the remaining issues is currently in progress. In conclusion, using the Delphi technique and GRADE methodology, consensus was reached in many issues regarding the treatment of PM and PMP amongst an international panel of experts. The main results will be published in the near future

Complications and Mortality Rate of Cytoreductive Surgery with Hyperthermic Intraperitoneal Chemotherapy: Italian Peritoneal Surface Malignancies Oncoteam Results Analysis

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

CpG-oligodeoxynucleotides exert remarkable antitumor activity against diffuse malignant peritoneal mesothelioma orthotopic xenografts

Background: Diffuse malignant peritoneal mesothelioma (DMPM) is a rare and locally aggressive disease. DMPM prognosis is dismal, mainly due to the lack of effective treatment options and the development of new therapeutic strategies is urgently needed. In this context, novel immunotherapy approaches can be explored in an attempt to improve DMPM patients' survival. Methods: We tested the efficacy of CpG-oligodeoxynucleotides (CpG-ODN), synthetic DNA sequences recognized by Toll-like receptor 9 and able to induce innate/adaptive immune response, in two DMPM orthotopic xenografts (MesoII and STO), which properly recapitulate the dissemination pattern of the disease in the peritoneal cavity. Severe combined immunodeficiency mice carrying DMPM xenografts were treated at different stages of tumor development with i.p. delivered CpG-ODN1826 for 4weeks. CpG-ODN1826-induced modulation in the composition of peritoneal immune infiltrate was assessed by flow cytometry. Results: When administered to early-stage tumors (i.e., 4days after i.p. DMPM cell injection in mice), the agent exhibited impressive efficacy against MesoII by completely inhibiting tumor take and ascites development (no evidence of tumor masses and ascites in 6/6 mice at necropsy), and also impaired STO tumor take and growth (4/6 tumor-free mice; i.p. tumor masses reduced by 94% in the 2 remaining mice, P=0.00005). Interestingly, when tested against late-stage STO tumors (i.e., 11days after i.p. DMPM cell injection in mice), CpG-ODN1826 was still able to reduce the growth of i.p. tumor masses by 66% (P=0.0009). Peritoneal washings of tumor-bearing mice revealed a strong increase of macrophage infiltration together with a decrease in the presence of B-1 cells and a reduced IgM concentration after CpG-ODN1826 treatment. Conclusions: Our results indicate that locally administered CpG-ODN1826 is able to markedly affect the growth of both early- and late-stage DMPM orthotopic xenografts in the absence of severe side effects, and suggest a possible clinical role for the agent in the therapy of DMPM

Anti-tumor activity of selective inhibitors of XPO1/CRM1-mediated nuclear export in diffuse malignant peritoneal mesothelioma : the role of survivin

Survivin, which is highly expressed and promotes cell survival in diffuse malignant peritoneal mesothelioma (DMPM), exclusively relies on exportin 1 (XPO1/ CRM1) to be shuttled into the cytoplasm and perform its anti-apoptotic function. Here, we explored the efficacy of Selective Inhibitors of Nuclear Export (SINE), KPT-251, KPT-276 and the orally available, clinical stage KPT-330 (selinexor), in DMPM preclinical models. Exposure to SINE induced dose-dependent inhibition of cell growth, cell cycle arrest at G1-phase and caspase-dependent apoptosis, which were consequent to a decrease of XPO1/CRM1 protein levels and the concomitant nuclear accumulation of its cargo proteins p53 and CDKN1a. Cell exposure to SINE led to a time-dependent reduction of cytoplasmic survivin levels. In addition, after an initial accumulation, the nuclear protein abundance progressively decreased, as a consequence of an enhanced ubiquitination and proteasome-dependent degradation. SINE and the survivin inhibitor YM155 synergistically cooperated in reducing DMPM cell proliferation. Most importantly, orally administered SINE caused a significant antitumor effect in subcutaneous and orthotopic DMPM xenografts without appreciable toxicity. Overall, we have demonstrated a marked efficacy of SINE in DMPM preclinical models that may relay on the interference with survivin intracellular distribution and function. Our study suggests SINE-mediated XPO1/ CRM1 inhibition as a novel therapeutic option for DMPM

Past, present and future of adjuvant HIPEC in patients at high risk for colorectal peritoneal metastases

EDITORIA

Feasibility of peritonectomy associated with intraperitoneal hyperthermic perfusion in patients with Pseudomyxoma peritonei

Aims and background: Pseudomyxoma peritonel is a rare disease characterized by a complete redistribution of mucin within the peritoneal cavity. It can be classified into three histologic groups: disseminated peritoneal adenomucinosis, peritoneal mucinous carcinomatosis, and an intermediate group. The aim of the present study was to evaluate the feasibility of cytoreductive surgery requiring peritonectomy procedures associated with intraperitoneal hyperthermic perfusion, a technique that combines hyperthermia and high drug doses administered locally. Methods: Twenty-seven patients with pseudomyxoma peritonei (19 males and 8 females) were enrolled in a phase 11 clinical trial. Twenty-two cases underwent cytoreductive surgery plus intraperitoneal hyperthermic perfusion, and 6 received debulking surgery only. One patient was operated on twice for disease recurrence. All patients with peritoneal mucinous carcinomatosis presented serous ascites, whereas all but one patient with disseminated peritoneal adenomucinosis or in the intermediate group presented mucinous ascites. Cytoreductive surgery was performed with peritonectomy procedures. The closed abdomen technique was adopted for intraperitoneal hyperthermic perfusion using a preheated polysaline perfusate containing cisplatin (25 mg/m(2)/L) plus mitomycin-C (3.3 mg/m(2)/L) through a heart-lung pump at a mean flow of 600 mL/min for 60 mins from the hyperthermic phase (42.5 degreesC). Results: All but one of the patients with disseminated peritoneal adenomucinosis and 2 of the 3 patients in the intermediate group were optimally cytoreduced. Patients with serous ascites (all patients with peritoneal mucinous carcinomatosis and 1 patient with disseminated peritoneal adenomucinosis) were considered ineligible for treatment because of tumor diffusion. The morbidity rate was 22%. There was one case of treatment-related mortality 30 days after treatment. Conclusions: The following conclusions can be drawn from this phase 11 clinical trial: 1) patients with pseudomyxoma perk tonei originating from undifferentiated mucinous adenocarcinoma (peritoneal mucinous carcinomatosis), with complete distribution into the peritoneal cavity, are not eligible for the cytoreductive surgery plus intraperitoneal hyperthermic perfusion technique; 2) the presence of serous ascites would seem to exclude patients from the treatment; 3) cytoreductive surgery associated with intraperitoneal hyperthermic perfusion is the most suitable approach for patients with disseminated peritoneal adenomucinosis and in the intermediate group

Should a History of Extraperitoneal Disease Be a Contraindication to Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Colorectal Cancer Peritoneal Metastases?

BACKGROUND: Survival improvements have been reported in selected patients affected by colorectal peritoneal metastases who were undergoing cytoreductive surgery with intraperitoneal hyperthermic chemotherapy. Treatment of peritoneal metastases associated with extraperitoneal disease is still controversial. OBJECTIVE: We assessed the prognostic impact of a history of extraperitoneal disease that was curatively treated either at the same time as or before the onset of peritoneal metastases. DESIGN: We reviewed 2 prospective databases. Peritoneal involvement was scored by Peritoneal Cancer Index. SETTINGS: Our study was conducted in 2 high-volume peritoneal malignancy management institutions. PATIENTS: A total of 148 patients with peritoneal metastases were included. In 27 patients, extraperitoneal disease involving the liver (n = 23), lung (n = 1), both lung and liver (n = 2), or inguinal lymph nodes and liver (n = 1) was curatively treated either simultaneously with peritoneal metastases (n = 22) or before their onset (n = 5). INTERVENTIONS: All of the macroscopic tumors were removed by means of peritonectomy procedures and visceral resections. Microscopic residual disease was treated by mitomycin C/cisplatin-based hyperthermic intraperitoneal chemotherapy. MAIN OUTCOME MEASURES: Overall survival was the primary outcome measure. RESULTS: After a median follow-up of 34.6 months (95% CI, 22.6-65.7 mo), 5-year survival of patients treated for both peritoneal and extraperitoneal disease versus peritoneal metastases alone was 16.5% versus 52.0% (p = 0.019). After multivariate analysis, reduced survival correlated with extraperitoneal disease (p = 0.001), Peritoneal Cancer Index >19 (p = 0.004), and peritoneal residual disease >2.5mm (p = 0.018). Three prognostic groups were defined, and median survival was not reached for group 1 (Peritoneal Cancer Index 19 and no extraperitoneal disease), reached in 27.0 months for group 2 (Peritoneal Cancer Index 9 and extraperitoneal disease), and reached in 11.6 months for group 3 (Peritoneal Cancer Index >19 and no extraperitoneal disease or Peritoneal Cancer Index >9 and extraperitoneal disease). LIMITATIONS: The main study limitation is its observational nature. CONCLUSIONS: A history of extraperitoneal disease is associated with poorer prognosis. However, survival benefit may be obtained in selected patients with limited peritoneal involvement. See Video Abstract at http://links.lww.com/DCR/A655