The role of perioperative systemic chemotherapy in diffuse malignant peritoneal mesothelioma patients treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

Genomic characterization and detection of potential therapeutic targets for peritoneal mesothelioma in current practice

Peritoneal mesothelioma (PeM) is an aggressive tumor with limited treatment options. The current study aimed to evaluate the value of next generation sequencing (NGS) of PeM samples in current practice. Foundation Medicine F1CDx NGS was performed on 20 tumor samples. This platform assesses 360 commonly somatically mutated genes in solid tumors and provides a genomic signature. Based on the detected mutations, potentially effective targeted therapies were identified. NGS was successful in 19 cases. Tumor mutational burden (TMB) was low in 10 cases, and 11 cases were microsatellite stable. In the other cases, TMB and microsatellite status could not be determined. BRCA1 associated protein 1 (BAP1) mutations were found in 32% of cases, cyclin dependent kinase inhibitor 2A/B (CDKN2A/B) and neurofibromin 2 (NF2) mutations in 16%, and ataxia-telangiectasia mutated serine/threonine kinase (ATM) in 11%. Based on mutations in the latter two genes, potential targeted therapies are available for approximately a quarter of cases (i.e., protein kinase inhibitors for three NF2 mutated tumors, and polyADP-ribose polymerase inhibitors for two ATM mutated tumors). Extensive NGS analysis of PeM samples resulted in the identification of potentially effective targeted therapies for about one in four patients. Although these therapies are currently not available for patients with PeM, ongoing developments might result in new treatment options in the future.

Is extereme cytoreductive surgery beneficial to survival ın malignant peritoneal mesothelioma?

INTRODUCTION

Malign peritoneal mesothelioma (MPM) is an uncommon disease that is difficult to treat. Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) are the gold standards for treating MPM. Sometimes extreme cytoreductive surgery (eCRS) is required to achieve complete cytoreduction, which is one of the most important prognostic factors. There is limited information in the literature about the contribution of eCRS in patients with MPM. In this study, we aimed to investigate the impact of eCRS on survival and perioperative outcomes.

METHODS

The Department of Surgical Oncology at Cumhuriyet University database was retrospectively reviewed for MPM patients who underwent CRS-HIPEC between January 2004 and December 2018. Patients who underwent CRS-HIPEC were divided into eCRS and less extensive CRS (leCRS) groups. A resection of ≥5 organs or ≥3 small bowel anastomoses were defined as eCRS. Both groups were compared regarding survival, demographic information, and perioperative outcomes.

RESULTS

A total of 31 patients were included. eCRS-HIPEC was used in 15 patients. Complete cytoreduction (CC score 0/1) was achieved in all 31 patients. Compared to leCRS, the eCRS group had a longer median length of stay, longer intensive care unit stay, a higher median peritoneal cancer index (PCI), higher intraoperative blood loss, more frequent occurrence of any complication, and a longer operative time (all p values < 0.001). Clavien Dindo 3-4 complications, ASA, and gender were similar in both groups of patients (p > 0.05). It was found that there was no significant difference between the OS of the eCRS and leCRS groups (37.5 vs. 42.8 months, p = 0.895).

CONCLUSIONS

Rates of serious complications and morbidity are similar in patients undergoing eCRS compared to leCRS. In patients with high PCI and multiorgan involvement, complete cytoreduction can be achieved by performing eCRS, and survival results equivalent to those with low PCI can be achieved.

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.

Randomized trial of intravenous versus bidirectional chemotherapy after cytoreductive surgery for malignant peritoneal mesothelioma

Background

Malignant peritoneal mesothelioma (MPM) is a rare disease that progresses within the peritoneal cavity and only disseminates to systemic sites in the terminal months of the disease. For this malignancy, there are several regimens of chemotherapy that have been accepted as standard, principally intraperitoneal chemotherapy (IPC) and intravenous chemotherapy (IVC); however, there is no standardized method of treatment. Selected patients with MPM who are amenable to cytoreductive surgery (CRS) and are fit for surgery typically undergo resection with hyperthermic intraperitoneal chemotherapy (HIPEC). Though individual toxicity and efficacy studies of IPC plus IVC (bidirectional) and IVC chemotherapy for MPM have been conducted, a prospective randomized clinical trial has not been performed for this disease.

Materials and methods

The study objective is to compare the efficacy and toxicity of normothermic bidirectional (IPC/IVC) chemotherapy versus IVC after CRS and HIPEC for epithelial MPM. The patient population are those individuals undergoing CRS for MPM. Exclusion criteria include previous therapy form mesothelioma. The study design is a randomized, nonblinded, phase II clinical trial comparing multicycle IVC with cisplatin (CDDP) and pemetrexed (PMTX) versus multicycle bidirectional chemotherapy with IVC CDDP and IPC PMTX after optimal CRS and HIPEC with CDDP and doxorubicin. The primary endpoint is 2-year disease-free survival. The secondary endpoint is 30-day post-treatment morbidity. The primary objective is to compare the 2-year rates of disease-free survival in the two treatment arms. The secondary objective is to compare the toxicity of each treatment.

Dissemination

The prospective randomized trial provides not only a standardized approach to treatment but also a path forward to optimize the survival of patients with MPM. In addition, any increase or decrease in the adverse events associated with PMTX administered as IPC will be demonstrated. Because MPM is a rare disease a multi-institutional implementation of the protocol is required.

Adjuvant dendritic cell-based immunotherapy after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in patients with malignant peritoneal mesothelioma: a phase II clinical trial

BACKGROUND

Malignant peritoneal mesothelioma (MPM) is an aggressive malignancy with a poor prognosis. Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) improves survival outcomes, but recurrence rates remain high. Dendritic cell-based immunotherapy (DCBI) showed promising results in patients with pleural mesothelioma. The primary aim of this trial was to determine feasibility of adjuvant DCBI after CRS-HIPEC.

METHODS

This open-label, single-center, phase II clinical trial, performed in the Erasmus MC Cancer Institute Rotterdam, the Netherlands, included patients with epithelioid MPM. 4-6 weeks before CRS-HIPEC leukapheresis was performed. 8-10 weeks after surgery, DCBI was administered three times biweekly. Feasibility was defined as administration of at least three adjuvant vaccinations in 75% of patients. Comprehensive immune cell profiling was performed on peripheral blood samples prior to and during treatment.

RESULTS

All patients who received CRS-HIPEC (n=16) were successfully treated with adjuvant DCBI. No severe toxicity related to DCBI was observed. Median progression-free survival (PFS) was 12 months (IQR 5-23) and median overall survival was not reached. DCBI was associated with increased proliferation of circulating natural killer cells and CD4+ T-helper (Th) cells. Co-stimulatory molecules, including ICOS, HLA-DR, and CD28 were upregulated predominantly on memory or proliferating Th-cells and minimally on CD8+ cytotoxic T-lymphocytes (CTLs) after treatment. However, an increase in CD8+ terminally differentiated effector memory (Temra) cells positively correlated with PFS, whereas co-expression of ICOS and Ki67 on CTLs trended towards a positive correlation.

CONCLUSIONS

Adjuvant DCBI after CRS-HIPEC in patients with MPM was feasible and safe, and showed promising survival outcomes. DCBI had an immune modulatory effect on lymphoid cells and induced memory T-cell activation. Moreover, an increase of CD8+ Temra cells was more pronounced in patients with longer PFS. These data provide rationale for future combination treatment strategies.

TRIAL REGISTRATION NUMBER

NTR7060; Dutch Trial Register (NTR).

High-Risk Peritoneal Mesothelioma: Does Metronomic Chemotherapy Have a Role?

Objective

To evaluate the feasibility, tolerance, and efficacy of OMCT (oral metronomic chemotherapy) after CRS + HIPEC for peritoneal mesothelioma in patients with poor prognostic factors: PCI > 20, incomplete CRS, poor performance status, or progression on systemic chemotherapy.

Methods

A retrospective analysis of patients undergoing CRS + HIPEC for peritoneal mesothelioma and receiving OMCT for poor risk factors.

Results

Sixteen patients underwent CRS + HIPEC between 2013 and 2017. The median PCI was 31.5. Complete cytoreduction (CC-0/1) was obtained in 8 patients (50%). All 16 received HIPEC except one patient with baseline renal dysfunction.Thirteen patients had PCI > 20 where only 5 had CC-0/1. Of 8 suboptimal cytoreduction (CC-2/3), 7 received OMCT (6 for progression on chemotherapy and one for mixed histology). Three patients had PCI < 20 and all had CC-0/1 clearance. Only one received OMCT for progression on adjuvant chemotherapy. Patients receiving OMCT for progression on adjuvant chemotherapy (ACT) were in poor PS.The median follow-up was 13.4 months. Five are alive with the disease (three are on OMCT). Six are alive without disease (2 are on OMCT). The mean OS was 24.3 months and the mean DFS was 18 months. Outcomes were similar between CC-0/1 and CC-2/3 groups, OMCT vs no OMCT groups.All patients receiving OMCT for progression on neoadjuvant chemotherapy had better survival (alive at 12, 20, 32, 36 months) compared to those receiving OMCT for progression on the ACT (p = 0.012).

Conclusion

OMCT is a good alternative in high-volume peritoneal mesothelioma with incomplete cytoreduction and progression on chemotherapy. OMCT may improve outcomes in these scenarios when started early.

Peritoneal Mesothelioma: Systematic Review of Hyperthermic Intraperitoneal Chemotherapy (HIPEC) Protocol Outcomes

Diffuse malignant peritoneal mesothelioma (DMPM) prognosis was improved by the locoregional treatment combining cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). HIPEC is a multiparametric treatment with multiple protocols proposed and reviewed in this work. A systematic review of medical literature was performed according to PRISMA guidelines. The search strategy used "malignant peritoneal mesothelioma" and "HIPEC" as keywords in three databases. Studies were included if reporting precisely the HIPEC regimen and the related outcomes, if comparing regimen, or if reporting national/international guidelines. The GRADE methodology was used to rate the level of evidence. Twenty-eight studies were included in this review: 1 was a meta-analysis, 18 reported cohort outcomes, 4 retrospectively compared HIPEC regimens, and 5 were guidelines. Six HIPEC regimens were found, 4 with one drug (cisplatin, mitomycine-C, carboplatin, oxaliplatin), 2 using two drugs (cisplatin-doxorubicin or cisplatin-mitomycine-C). Cisplatin, up to 250 mg/m2 over 90 min, appeared as the key HIPEC drug with a toxicity profile well controlled by the concomitant intravenous perfusion of sodium thiosulfate. Comparative studies tended to show that a bi-drug regimen led to better long-term oncologic outcomes, with cisplatin 50 mg/m2 plus doxorubicin 15 mg/m2 being safe and more efficient. This late protocol was the most widely used and recommended in 3 out of 4 international guidelines. Cisplatin was the preferred drug for HIPEC in DMPM patients. Most of the time, it was combined with doxorubicin for 90 min. A harmonization of protocols and further comparative studies are needed to optimize HIPEC regimen choice.

Peritoneal Mesothelioma in a High Volume Peritoneal Surface Malignancies Unit

Diffuse malignant peritoneal mesothelioma (PM) is a rare neoplasm, traditionally associated with a poor prognosis. There are other varieties of PM that are even less frequent and of uncertain malignancy. Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) has achieved prolonged survival in selected patients. The aim of this study is to analyze the patients with PM assessed in our center. Clinicopathological characteristics, diagnostic procedures and survival results from patients with PM appraised at our unit, according to the applied treatment, were analyzed. Seventeen patients were assessed between 2007 and 2019. Three cases had multicystic PM that were treated with complete CRS + HIPEC; all patients are alive and free of disease after a long follow-up. Three other cases had biphasic PM; a curative treatment could be performed in none of them, and their survival was minimal (<6 moths). Lastly, 11 cases with epithelioid PM were treated. Two cases were considered unresectable at laparoscopy (PCI 39); one of them had a long survival (67 months) with three iterative laparoscopic palliatives HIPECs for refractory ascites. The other nine cases were treated with curative CRS + HIPEC, with a median PCI of 14 (range 4–25), and a median overall survival (OS) of 58 months, with a 5-year OS of 47.4%. In conclusion, CRS + HIPEC, when possible, appears to be the optimal treatment for patients with PM. Knowledge of this therapeutic option is crucial, both to offer it to patients and to avoid delays in their referral to appropriate centers for treatment.

Diagnostic and Therapeutic Pathway in Diffuse Malignant Peritoneal Mesothelioma

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).

A single-center retrospective cohort study of perioperative systemic chemotherapy in diffuse malignant peritoneal mesothelioma

Background

Diffuse malignant peritoneal mesothelioma (DMPM) is a rare variant of malignant mesothelioma, representing 10–15% of malignant mesothelioma cases. The preferred therapeutic approach is cytoreductive surgery (CRS) accompanied by hyperthermic intraperitoneal chemotherapy (HIPEC); the role of systemic chemotherapy is not well established. While some limited retrospective studies report worse outcomes with neoadjuvant chemotherapy, our institution has favored the use of neoadjuvant chemotherapy for symptom relief and surgical optimization. The aim of our study was to assess the outcomes of patients receiving neoadjuvant chemotherapy, compared to those receiving adjuvant or no perioperative chemotherapy.

Patients and methods

We conducted a single-center retrospective cohort study of treatment-naïve, non-papillary DMPM patients seen at our institution between 1/1/2009 and 9/1/2019. We explored the effect of type of systemic therapy on clinical outcomes and estimated median overall survival (mOS) using Kaplan-Meier curves. Hazard ratios (HR) calculated by Cox proportional hazard model were used to estimate effect of the exposures on overall survival.

Results

47 patients were identified with DMPM (median age at diagnosis 61.2 years, 76.6% epithelioid histology, 74.5% white race, 55.3% known asbestos exposure). CRS was performed in 53.2% of patients (25/47); 76.0% of surgical patients received HIPEC (19/25). The majority received systemic chemotherapy (37/47, 78.7%); among patients receiving both CRS and chemotherapy, neoadjuvant chemotherapy was more common than adjuvant chemotherapy (12 neoadjuvant, 8 adjuvant). Overall mOS was 84.1 months. Among neoadjuvant patients, 10/12 underwent surgery, and 2 were lost to follow-up; the majority (9/10) had clinically stable or improved disease during the pre-operative period. There were numerical more issues with chemotherapy with the adjuvant patients (4/8: 2 switches in platinum agent, 2 patients stopped therapy) than with the neoadjuvant patients (2/10: 1 switch in platinum agent, 1 delay due to peri-procedural symptoms). Neoadjuvant chemotherapy was not associated with worse mOS compared to adjuvant chemotherapy (mOS NR vs 95.1 mo, HR 0.89, 95% CI 0.18–4.5, p = 0.89).

Conclusions

When used preferentially, the use of neoadjuvant chemotherapy in DMPM patients was not associated with worse outcomes compared to adjuvant chemotherapy. It was well-tolerated and did not prevent surgical intervention.

Advances in the management of peritoneal malignancies

Peritoneal surface malignancies (PSMs) are usually associated with a poor prognosis. Nonetheless, in line with advances in the management of most abdominopelvic metastatic diseases, considerable progress has been made over the past decade. An improved understanding of disease biology has led to the more accurate prediction of neoplasia aggressiveness and the treatment response and has been reflected in the proposal of new classification systems. Achieving complete cytoreductive surgery remains the cornerstone of curative-intent treatment of PSMs. Alongside centralization in expert centres, enabling the delivery of multimodal and multidisciplinary strategies, preoperative management is a crucial step in order to select patients who are most likely to benefit from surgery. Depending on the specific PSM, the role of intraperitoneal chemotherapy and of perioperative systemic chemotherapy, in particular, in the neoadjuvant setting, is established in certain scenarios but questioned in several others, although more prospective data are required. In this Review, we describe advances in all aspects of the management of PSMs including disease biology, assessment and improvement of disease resectability, perioperative management, systemic therapy and pre-emptive management, and we speculate on future research directions.

Non-resectable Malignant Peritoneal Mesothelioma Treated with Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) Plus Systemic Chemotherapy Could Lead to Secondary Complete Cytoreductive Surgery: A Cohort Study

BACKGROUND

Diffuse malignant peritoneal mesothelioma (DMPM) is an aggressive primary peritoneal neoplasia. At diagnosis, few patients are eligible for a recommended cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Among neoadjuvant strategies, pressurized intraperitoneal aerosol chemotherapy (PIPAC) combined with systemic chemotherapy has been recently proposed. This study evaluated this strategy in a cohort of DMPM patients.

METHODS

Patients with DMPM and primary or recurrent non-resectable diseases who received at least one PIPAC procedure in alternation with systemic chemotherapy were included in this retrospective study to analyze oncologic outcomes.

RESULTS

Overall, 26 DMPM patients were treated with at least one PIPAC, including 20 patients with no previous CRS. Of 22 patients (85%) who had symptoms, 9 had perceptible ascites. Overall, 79 PIPAC procedures were performed, with half of the patients receiving three PIPAC procedures or more. Among eight patients (31%), 10 adverse events (13% of procedures) were reported, including two severe complications, both corresponding to digestive perforations. Improvement of symptoms was reported for 32% of the patients, whereas control of ascites was noted in 46%. All but one procedure among 14 patients (54%) secondarily treated by CRS-HIPEC were considered complete resections. After a median follow-up period of 29.6 months (95% confidence interval [CI], 17.6-not reached [NR]), the median overall survival period was 12 months (95% CI 11.1-NR). The median progression-free survival (PFS) was significantly better among the patients who underwent resection than among those who did not (33.5 vs 7.4 months; hazard ratio [HR], 0.18; 95% CI 0.06-0.755; p < 0.001).

CONCLUSIONS

For patients with initially non-resectable DMPM, PIPAC is feasible for treatment with neoadjuvant intent and could facilitate complete secondary resection.

Hyperthermic Intraperitoneal Chemotherapy (HIPEC) in the management of peritoneal surface malignancies - An evidence-based review

BACKGROUND

Traditionally, peritoneal surface malignancies (PSM) were considered terminal diseases because of their advanced nature, therefore, systemic chemotherapy was given with palliative intent only. As a result, very poor survival outcomes were observed. But with the introduction of complete Cytoreductive surgery (CRS) and Hyperthermic intraperitoneal chemotherapy (HIPEC), the scenario has changed dramatically.

METHODOLOGY

An objective electronic database search was performed in Pubmed, NLM Catalog, Google scholar, Bookshelf, and Pubmed Central published in the time period from 2000 till 2020. All the randomized studies were included. In the absence of randomized studies, both prospective and retrospective studies were included. The outcomes of HIPEC were measured in terms of median survival, disease-free survival, overall survival, complications and drug toxicities.

RESULTS

CRS and HIPEC are considered the standard of care for PMP and MPM even in the absence of level 1 evidence due to lack of an effective alternative treatment. In colorectal and gastric cancer, several phase-three trials are showing overall survival benefit in selected cases while there is a prophylactic and palliative role of HIPEC in gastric cancer. Three reported phase 3 trials showed positive results in ovarian cancer. In peritoneal sarcomatosis, the role of HIPEC is yet to be proven.

CONCLUSION

The patient selection is the key to the successful outcomes after HIPEC. HIPEC should be performed by the experienced surgeons in specialized centres with a strong critical care and intensive care support to reduce the morbidity and mortality. Ongoing trials and future directions will prove to be an indispensable arm in the oncological armamentarium.

Tertiary lymphoid structures in epithelioid malignant peritoneal mesothelioma are associated with neoadjuvant chemotherapy, but not with prognosis

Epithelioid mesothelioma is the most prevalent subtype of diffuse malignant peritoneal mesothelioma. The relationship between a strong adaptive immune response and a better prognosis in malignant solid tumors is widely known. Due to the low incidence of epithelioid malignant peritoneal mesothelioma (EMPM), very little is known about their immune micro-environment. We encountered several cases of tertiary lymphoid structures in EMPM in a previous study and aimed to investigate in the same series the prevalence, clinicopathological features, and the prognostic impact associated with tertiary lymphoid structures in EMPM (TLS-EMPM). Cases of EMPM, from 1995 to 2018, were retrieved from 7 French institutions from the RENAPE Network. The predictions in terms of overall survival (OS) and progression-free survival (PFS) of TLS-EMPM were analyzed. We report 52 cases of TLS-EMPM among a series of 138 cases of EMPM. TLS-EMPM was significantly associated with neoadjuvant chemotherapy, and was not a prognostic indicator for OS (p = 0.652) and PFS (p = 0.804) in our series. TLS is a component of the host immune response to EMPM significantly associated with neoadjuvant chemotherapy, but was not a predictor of prognosis for overall and progression-free survivals in this series. These findings provide another possible etiology for tertiary lymphoid structures.

Prolonged survival with systemic chemotherapy in an advanced malignant mesothelioma: A case report

Peritoneal mesotheliomas are very rare tumors. Their prognosis is poor, average survival does not exceed 1 year after peritoneal cytoreduction. Systemic chemotherapy is considered to have no proven value in the management of peritoneal mesotheliomas. Objective responses with systemic chemotherapy are very rare. We report here a case of an advanced peritoneal mesothelioma which achieved an unexpected partial response with chemotherapy, allowing the patient to have a right colectomy. The patient was referred to a specialized center on HIPEC, but taking in account the long awaiting interval, the HIPEC was judged to be inefficient and then the poursuit of 6 cycles of systemic chemotherapy was decided. The patient is still alive without any symptom and with a good performance status at 59 months after diagnosis. Throughout our case, we provide an encouraging evidence of the role of initial systemic chemotherapy in the downstaging of initially unresectable primary malignant mesothelioma and in the improvement of overall survival.

The Role of Hyperthermic Intraperitoneal Chemotherapy for Non-colorectal Peritoneal Surface Malignancies

BACKGROUND

Peritoneal carcinomatosis, from a variety of gastrointestinal and gynecological malignancies, has been historically challenging to treat and there remains a wide range of biologic aggressiveness in these patients. Malignancies commonly associated with PC include those of colorectal, appendiceal, gastric, ovarian, sarcoma, small intestinal, and primary peritoneal origin among others. Advances in our understanding of this unique disease process have led to significant interest in cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) as an emerging treatment option. The goal of CRS-HIPEC is to remove all visible macroscopic disease while preserving organ function, and then treat microscopic disease through perfusion of the peritoneal cavity with heated chemotherapy.

PURPOSE

Although recent reviews have focused on the management of peritoneal carcinomatosis secondary to colorectal cancer given the publication of several recent randomized controlled trials, the purpose of the current review is to summarize the evidence on CRS-HIPEC for non-colorectal peritoneal surface malignancies, including appendiceal neoplasms, malignant peritoneal mesothelioma, gastric cancer, and ovarian cancer.

RESULTS

While retrospective studies have clarified the importance of prognostic factors such as the peritoneal carcinomatosis index, completeness of cytoreduction, histopathological characteristics, and lymph node positivity, the lack of convincing level 1 evidence for the use of CRS-HIPEC has led to it remaining a highly controversial topic.

CONCLUSION

The decision to utilize CRS-HIPEC should involve a multidisciplinary team approach and evaluation of prognostic factors to balance the short-term morbidity of the operation with maximum long-term benefits. Large, multi-institutional groups and ongoing trials hold promise for clarifying the role of CRS-HIPEC in peritoneal surface malignancies.

[Treatment of primary and metastatic peritoneal tumors in the Covid-19 pandemic. Proposals for prioritization from the RENAPE and BIG-RENAPE groups]

La pandémie de COVID-19 modifie profondément l’organisation et l’accès aux soins, en particulier pour les pathologies néoplasiques péritonéales, dont la prise en charge curative mobilise des moyens importants en personnel, bloc opératoire et réanimation. Les groupes BIG-RENAPE et RENAPE proposent des pistes de réflexion et de priorisation pour leur prise en charge. Un renforcement des critères habituels de sélection est nécessaire pour une prise en charge à visée curative : patients jeunes, avec peu de co-morbidités et une extension péritonéale limitée. Il est souhaitable de prioriser les pathologies pour lesquelles la chirurgie de cytoréduction associée ou non à une chimiohyperthermie intrapéritonéale (CHIP) est le traitement de référence et celles pour lesquelles la chimiothérapie systémique ne peut être une alternative temporaire ou prolongée : pseudomyxomes péritonéaux ; mésothéliomes péritonéaux malins résécables ; métastases péritonéales d’origine colorectale si résécables, non répondeuses à la chimiothérapie systémique et/ou après 12 cures, carcinoses ovariennes en 1^re intention si résécables et limitées ou en situation intervallaire après un maximum de 6 cycles de chimiothérapie systémique. L’adjonction d’une CHIP devra être discutée au cas par cas, en centre expert. La priorisation des indications devra prendre en considération les conditions locales et la phase de la période épidémique pour permettre une prise en charge péri-opératoire optimale.

Treatment of primary and metastatic peritoneal tumors in the Covid-19 pandemic. Proposals for prioritization from the RENAPE and BIG-RENAPE groups

The Covid-19 pandemic is profoundly changing the organization of healthcare access. This is particularly so for peritoneal neoplastic diseases, for which curative treatment mobilizes substantial personnel, operating room and intensive care resources. The BIG-RENAPE and RENAPE groups have made tentative proposals for prioritizing care provision. A tightening of the usual selection criteria is needed for curative care: young patients with few or no comorbidities and limited peritoneal extension. It is desirable to prioritize disease conditions for which cytoreduction surgery with or without associated hyperthermic intraoperative peritoneal chemotherapy (HIPEC) is the gold-standard treatment, and for which systemic chemotherapy cannot be a temporary or long-term alternative: pseudomyxoma peritonei, resectable malignant peritoneal mesotheliomas, peritoneal metastases of colorectal origin if they are resectable and unresponsive to systemic chemotherapy after up to 12 courses, first-line ovarian carcinomatosis if resectable or in interval surgery after at most six courses of systemic chemotherapy. Addition of HIPEC must be discussed case by case in an expert center. The prioritization of indications must consider local conditions and the phase of the epidemic to allow optimal peri-operative care.

Malignant Peritoneal Mesothelioma: Patterns of Care and Survival in the Netherlands: A Population-Based Study

BACKGROUND

Malignant peritoneal mesothelioma (MPM) is a rare and aggressive disease. Recently, focus has shifted toward a more aggressive and multimodal treatment approach. This study aimed to assess the patterns of care and survival for MPM patients in the Netherlands on a nationwide basis.

METHODS

The records of patients with a diagnosis of MPM from 1993 to 2016 were retrieved from the Dutch Cancer Registry. Data regarding diagnosis, staging, treatment, and survival were extracted. Cox regression analyses and Kaplan-Meier survival curves were used to study overall survival.

RESULTS

Between 1993 and 2016, MPM was diagnosed for 566 patients. Overall, the prognosis was very poor (24% 1-year survival). The most common morphologic subtype was the epithelioid subtype (88%), followed by the biphasic (8%) and sarcomatoid (4%) subtypes. Surgical treatment has become more common in recent years, which most likely has resulted in improved survival rates. In this study, improved survival was independently associated with hyperthermic intraperitoneal chemotherapy (hazard ratio [HR], 0.33; 95% confidence interval [CI], 0.21-0.55) and surgery with adjuvant systemic chemotherapy (HR, 0.33; 95% CI, 0.23-0.48). Nonetheless, most patients (67%) do not receive any form of anti-cancer treatment.

CONCLUSION

This study indicated that MPM still is a rare and fatal disease. The survival rates in the Netherlands have improved slightly in the past decade, most likely due to more aggressive treatment approaches and increased use of surgery. However, most patients still do not receive cancer-directed treatment. To improve MPM management, and ultimately survival, care should be centralized in expert medical centers.

Mesothelioma: Scientific clues for prevention, diagnosis, and therapy

Mesothelioma affects mostly older individuals who have been occupationally exposed to asbestos. The global mesothelioma incidence and mortality rates are unknown, because data are not available from developing countries that continue to use large amounts of asbestos. The incidence rate of mesothelioma has decreased in Australia, the United States, and Western Europe, where the use of asbestos was banned or strictly regulated in the 1970s and 1980s, demonstrating the value of these preventive measures. However, in these same countries, the overall number of deaths from mesothelioma has not decreased as the size of the population and the percentage of old people have increased. Moreover, hotspots of mesothelioma may occur when carcinogenic fibers that are present in the environment are disturbed as rural areas are being developed. Novel immunohistochemical and molecular markers have improved the accuracy of diagnosis; however, about 14% (high-resource countries) to 50% (developing countries) of mesothelioma diagnoses are incorrect, resulting in inadequate treatment and complicating epidemiological studies. The discovery that germline BRCA1-asssociated protein 1 (BAP1) mutations cause mesothelioma and other cancers (BAP1 cancer syndrome) elucidated some of the key pathogenic mechanisms, and treatments targeting these molecular mechanisms and/or modulating the immune response are being tested. The role of surgery in pleural mesothelioma is controversial as it is difficult to predict who will benefit from aggressive management, even when local therapies are added to existing or novel systemic treatments. Treatment outcomes are improving, however, for peritoneal mesothelioma. Multidisciplinary international collaboration will be necessary to improve prevention, early detection, and treatment.

Adjuvant dendritic cell based immunotherapy (DCBI) after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal mesothelioma, a phase II single centre open-label clinical trial: rationale and design of the MESOPEC trial

INTRODUCTION

Malignant peritoneal mesothelioma (MPM) is an uncommon but aggressive neoplasm and has a strong association with asbestos exposure. MPM has low survival rates of approximately 1 year even after (palliative) surgery and/or systemic chemotherapy. Recent advances in treatment strategies focusing on cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have resulted in improved median survival of 53 months and a 5 year survival of 47%. However, recurrence rates are high. Current systemic chemotherapy in the adjuvant setting is of limited efficacy, while immunotherapy with dendritic cell based immunotherapy (DCBI) has yielded promising results in murine models with peritoneal mesothelioma and in patients with pleural mesothelioma.

METHODS AND ANALYSIS

The MESOPEC trial is an open-label single centre phase II study. The study population are adult patients with histological/cytological confirmed diagnosis of epithelioid malignant peritoneal mesothelioma.

INTERVENTION

4 to 6 weeks before CRS-HIPEC a leukapheresis is performed of which the monocytes are used for differentiation to dendritic cells (DCs). Autologous DCs pulsed with allogeneic tumour associated antigens (MesoPher) are re-injected 8 to 10 weeks after surgery, three times biweekly. Additional booster vaccinations are given at 3 and 6 months.Primary objective is to determine the feasibility of administering DCBI after CRS-HIPEC in patients with malignant peritoneal mesothelioma. Secondary objectives are to assess safety of DCBI in patients with peritoneal mesothelioma and determine whether a specific immunological response against the tumour occurs as a result of this adjuvant immunotherapy.

ETHICS AND DISSEMINATION

Permission to carry out this study protocol has been granted by the Central Committee on Research Involving Human Subjects (CCMO in Dutch) and the Research Ethics Committee (METC in Dutch). The results of this trial will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NTR7060. EudraCT: 2017-000897-12; Pre-Results.

Malignant peritoneal mesothelioma: clinical aspects, and therapeutic perspectives

Malignant peritoneal mesothelioma (MPM) is a rare disease with a wide clinical spectrum. It arises from the peritoneal lining and commonly presents with diffuse, extensive spread throughout the abdomen and, more rarely, metastatic spread beyond the abdominal cavity. Computed tomography, magnetic resonance imaging and positron-emission tomography are important diagnostic tools used for the preoperative staging of MPM. The definitive diagnosis is based on histopathological analysis, mainly via immunohistochemistry. In this regard, paired-box gene 8 negativity represents a useful diagnostic biomarker for differentiating MPM from ovarian carcinoma. In addition, BRCA1-associated protein-1 (BAP1) loss is specific to MPM and allows it to be distinguished from both benign mesothelial lesions and ovarian serous tumors. Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) has become an increasingly important therapeutic approach, while systemic therapies are still being developed. Histology, Ki-67, completeness of cytoreduction, age, sex, and baseline thrombocytosis are commonly used to optimize patient selection for CRS with HIPEC. Additionally, it is well recognized that, compared to other subtypes, an epithelial morphology is associated with a favorable prognosis, whereas baseline thrombocytosis predicts an aggressive biologicalbehavior. Platelets and other immunologic cytokines have been evaluated as potential novel therapeutic targets. Epigenetic modifiers, including BAP1, SETD2 and DDX3X, are crucial in mesothelial tumorigenesis and provide opportunities for targeted treatment. Overexpression of the closely interacting phosphoinositide 3-kinase (PI3K) and the mammalian target of rapamycin (mTOR) pathways appears crucial in regulation of the malignant phenotype. The use of targeted therapies with PI3K-mTOR-based inhibitors requires further clinical assessment as a novel approach.

A proposal of Brazilian Society of Surgical Oncology (BSSO/SBCO) for standardizing cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) procedures in Brazil: pseudomixoma peritonei, appendiceal tumors and malignant peritoneal mesothelioma

Cytoreductive surgery plus hypertermic intraperitoneal chemotherapy has emerged as a major comprehensive treatment of peritoneal malignancies and is currently the standard of care for appendiceal epithelial neoplasms and pseudomyxoma peritonei syndrome as well as malignant peritoneal mesothelioma. Unfortunately, there are some worldwide variations of the cytoreductive surgery and hypertermic intraperitoneal chemotherapy techniques since no single technique has so far demonstrated its superiority over the others. Therefore, standardization of practices might enhance better comparisons between outcomes. In these settings, the Brazilian Society of Surgical Oncology considered it important to present a proposal for standardizing cytoreductive surgery plus hypertermic intraperitoneal chemotherapy procedures in Brazil, with a special focus on producing homogeneous data for the developing Brazilian register for peritoneal surface malignancies.

Peritoneal Metastases from Malignant Mesothelioma

Diffuse malignant peritoneal mesothelioma (MPM) is a rare cancer that is ultimately fatal in almost all afflicted individuals. Morbidity and mortality from MPM is due to its propensity to progress locoregionally within the abdominal cavity. Patients with MPM most commonly present with nonspecific abdominal symptoms that usually lead to diagnosis when the condition is relatively advanced. MPM is considered a chemotherapy-resistant malignancy.

Current Management and Future Opportunities for Peritoneal Metastases: Peritoneal Mesothelioma

PURPOSE

Diffuse malignant peritoneal mesothelioma (MPM) is a rare and ultimately fatal cancer that was first described just over a century ago. It is a diffuse malignancy arising from the mesothelial lining of the peritoneum; morbidity and mortality from MPM is due to its propensity to progress locoregionally within the abdominal cavity.

METHODS

The purpose of this article is to review the current state-of-the-science related to the diagnosis, staging, and treatment of MPM.

RESULTS

The condition afflicts men and women equally and the peak incidence is between 55 and 60 years of age although it can arise in the young and elderly. Patients afflicted with MPM most commonly present with nonspecific abdominal symptoms that usually lead to diagnosis when the condition is relatively advanced. Historically, median overall survival for MPM patients without treatment is < 1 year. The couplet of systemic pemetrexed and cisplatin has an overall response rate of approximately 25% and a median overall survival of approximately 1 year.

CONCLUSION

The available data, almost all retrospective in nature, have shown that in selected patients, operative cytoreduction (CRS) and regional chemotherapy administered as hyperthermic intraoperative peritoneal chemotherapy (HIPEC) or early postoperative intraperitoneal chemotherapy (EPIC) is associated with long-term survival. Studies on the molecular biology of MPM have yielded new insights relating to the potentially important role of the phosphoinsitide-3-kinase/mammalian target of rapamycin (PI3 K/mTOR) pathways and immune checkpoint inhibitors that may translate into new therapeutic options for patients with diffuse MPM.

Clinical presentation, diagnosis, classification and management of peritoneal mesothelioma: a review

Peritoneal mesothelioma (PM) is an uncommon but a serious, and often, fatal primary peritoneal tumour, with increasing incidence worldwide. Conventional systemic chemotherapy, generally based on experience with pleural mesothelioma, usually has disappointing results considering PM as a terminal condition. Patients usually present with non-specific symptoms of abdominal distension and pain making the diagnosis challenging. As PM is confined to the abdomen for all, or much, of its clinical course, a multimodality treatment combining cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) has emerged as a new standard of care, and has been reported to achieve promising survival outcomes and local disease control in selected patients with PM. This review updates the presentation, diagnosis, classification and treatment strategies for PM.

Conversion to Complete Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Malignant Peritoneal Mesothelioma After Bidirectional Chemotherapy

BACKGROUND

This report aims to describe preliminary results concerning secondary resectability after bidirectional chemotherapy for initially unresectable malignant peritoneal mesothelioma (MPM).

METHODS

Between January 2013 and January 2016, 20 consecutive patients treated for diffuse MPM not suitable for upfront surgery received bidirectional chemotherapy associating intraperitoneal and systemic chemotherapy. Evaluation of the response to chemotherapy was assessed clinically and by laparoscopy.

RESULTS

The median peritoneal cancer index (PCI) score at staging laparoscopy was 27 (range 15-39). Altogether, 118 intraperitoneal chemotherapy cycles were administered without any specific adverse catheter-related event. Concerning tolerance, 85% of the patients experienced no pain or mild pain during chemotherapy administration. The clinical response rate was 60% after a median of three chemotherapy cycles. At laparoscopic reevaluation, the median PCI was 18 (range 0-35), and a secondary resectability was considered for 55% of the patients. Complete cytoreduction surgery followed by hyperthermic intraperitoneal chemotherapy (HIPEC) was finally achieved for 10 patients (50%), with a median intraoperative PCI score of 14 (range 6-30). After a median follow-up period of 18 months, the 2-year overall survival rate was 83.3% for the patients treated by CRS followed by HIPEC and 44% for the patients treated by bidirectional chemotherapy.

CONCLUSION

Bidirectional chemotherapy is a promising, well-tolerated treatment capable of increasing the resection rate for selected patients with diffuse MPM initially considered as unresectable or borderline resectable. For patients with definitively unresectable disease, bidirectional chemotherapy achieves a higher clinical response rate.

Evaluation of intracavitary administration of curcumin for the treatment of sarcomatoid mesothelioma

A rat model of sarcomatoid mesothelioma, mimicking some of the worst clinical conditions encountered, was established to evaluate the therapeutic potential of intracavitary curcumin administration.

The M5-T1 cell line, selected from a collection established from F344 rats induced with asbestos, produces tumors within three weeks, with extended metastasis in normal tissues, after intraperitoneal inoculation in syngeneic rats. The optimal concentration/time conditions for killing M5-T1 cells with curcumin were first determined in vitro. Secondly, the potential of intraperitoneal curcumin administration to kill tumor cells in vivo was evaluated in tumor-bearing rats, in comparison with a reference epigenetic drug, SAHA.

Both agents administered at days 21 and 26 after tumor challenge produced necrosis within the solid tumors at day 28. However, tumor tissue necrosis induced with curcumin was much more extensive than with SAHA, and was characterized by infiltration with mononuclear phagocytic cells. In contrast, tumor tissue treated with SAHA contained foci of resistant cells and was infiltrated by many isolated CD8+ cells. The treatment of tumor-bearing rats with 1.5 mg/kg curcumin on days 7, 9, 11 and 14 after tumor challenge dramatically reduced the mean total tumor mass at day 16. Clusters of CD8+ T lymphocytes were observed at the periphery of small residual tumor masses in the peritoneal cavity, which presented a significant reduction in mitotic index, IL6 and vimentin expression compared with tumors in untreated rats.

These data open up interesting new prospects for the therapy of sarcomatoid mesothelioma with curcumin and its derivatives.

Prognostic factors of hemorrhagic complications after oxaliplatin-based hyperthermic intraperitoneal chemotherapy: Toward routine preoperative dosage of Von Willebrand factor?

BACKGROUND

Oxaliplatin-based hyperthermic intraperitoneal chemotherapy (HIPEC-ox) induces specific morbidity with hemorrhagic complications (HC). The aim of this study was to identify preoperative, intraoperative and postoperative HC predictive factors after HIPEC-ox.

METHODS

A prospective single center study that included all consecutive patients treated with curative-intent HIPEC-ox, whatever the origin of peritoneal disease, was conducted. All patients underwent systematic blood tests exploring primary hemostasis and endothelial activation before surgical incision (D0) and on postoperative days 2 (POD2) and 5 (POD5).

RESULTS

Between May 2012 and August 2015, 47 patients were enrolled in the study. The overall HC rate was 38%. Major morbidity was significantly higher in patients with HC. Patients presenting HC were significantly more often affected with pseudomyxoma peritonei and had less preoperative chemotherapy. Multivariate analysis showed that a higher plasmatic level of Von Willebrand factor antigen at D0 (D0 VWF:Ag) was a protective predictive factor for HC (p = 0.049, HR: 0.97 CI 95% [0.94-1.00]). A D0 VWF:Ag level below 138% had a sensitivity of 87.5%, a specificity of 67% and an area under the curve of 80.3% (CI 95% [66.5-94], p < 0.01) for predicting HC.

CONCLUSIONS

Through the identification of prognostic factors, this study highlighted a subgroup of patients with low risk of HC after HIPEC-ox. Based on these results, we propose a routine preoperative dosage of VWF that would help the surgeon to select the most suitable patients for HIPEC-ox.

Antitumor activity of miR-34a in peritoneal mesothelioma relies on c-MET and AXL inhibition: persistent activation of ERK and AKT signaling as a possible cytoprotective mechanism

Background

The value of microRNAs (miRNAs) as novel targets for cancer therapy is now widely recognized. However, no information is currently available on the expression/functional role of miRNAs in diffuse malignant peritoneal mesothelioma (DMPM), a rapidly lethal disease, poorly responsive to conventional treatments, for which the development of new therapeutic strategies is urgently needed. Here, we evaluated the expression and biological effects of miR-34a—one of the most widely deregulated miRNAs in cancer and for which a lipid-formulated mimic is already clinically available—in a large cohort of DMPM clinical samples and a unique collection of in house-developed preclinical models, with the aim to assess the potential of a miR-34a-based approach for disease treatment.

Methods

miR-34a expression was determined by qRT-PCR in 45 DMPM and 7 normal peritoneum specimens as well as in 5 DMPM cell lines. Following transfection with miR-34a mimic, the effects on DMPM cell phenotype, in terms of proliferative potential, apoptotic rate, invasion ability, and cell cycle distribution, were assessed. In addition, three subcutaneous and orthotopic DMPM xenograft models were used to examine the effect of miR-34a on tumorigenicity. The expression of miRNA targets and the activation status of relevant pathways were investigated by western blot.

Results

miR-34a was found to be down-regulated in DMPM clinical specimens and cell lines compared to normal peritoneal samples. miR-34a reconstitution in DMPM cells significantly inhibited proliferation and tumorigenicity, induced an apoptotic response, and declined invasion ability, mainly through the down-regulation of c-MET and AXL and the interference with the activation of downstream signaling. Interestingly, a persistent activation of ERK1/2 and AKT in miR-34a-reconstituted cells was found to counteract the antiproliferative and proapoptotic effects of miRNA, yet not affecting its anti-invasive activity.

Conclusions

Our preclinical data showing impressive inhibitory effects induced by miR-34a on DMPM cell proliferation, invasion, and growth in immunodeficient mice strongly suggest the potential clinical utility of a miR-34a-replacement therapy for the treatment of such a still incurable disease. On the other hand, we provide the first evidence of a potential cytoprotective/resistance mechanism that may arise towards miRNA-based therapies through the persistent activation of RTK downstream signaling.

Electronic supplementary material

The online version of this article (doi:10.1186/s13045-016-0387-6) contains supplementary material, which is available to authorized users.

Pretreatment thrombocytosis as a significant prognostic factor in malignant mesothelioma: a meta-analysis

The current meta-analysis analyzed the prognostic impact of elevated platelet count before the treatment of malignant mesothelioma (MM). We performed a search for articles published up to April 15, 2016 in PubMed, MEDLINE, EMBASE, and Web of Science, which evaluated elevated platelet count and survival outcome of MM. STATA version 12 was used for statistical analysis. The pooled hazard ratios (HRs) and their 95% confidence intervals (CIs) were combined to calculate overall effects. The assessment of heterogeneity was tested by the Cochran Q and I² statistics. The sensitivity and meta-regression analyses were performed to explore the origin of heterogeneity. We analyzed 18 eligible studies (3602 patients) that evaluated the correlation between pretreatment platelet count and overall survival (OS). Elevated platelet count was a prognostic factor of poor OS, with a pooled HR of 1.56 (95% CI = 1.36-1.77). However, significant heterogeneity was observed in the included studies (I² = 86.0%, p < 0.001). Sensitivity and meta-regression analyses were performed to trace the origin of heterogeneity. Only the variable type (multivariable or univariate model) was traced as the origin of heterogeneity. Hence, we conducted a subgroup analysis of variable type. The HR was 1.66 (95% CI = 1.41-1.91) in the multivariable group and no significant heterogeneity was observed (I² = 0.0%, p = 0.476). In conclusion, high pretreatment platelet count resulted in poor OS in MM. Therefore, platelet count could be an adequate and useful factor of prognosis for MM.

Preclinical Activity of New [1,2]Oxazolo[5,4-e]isoindole Derivatives in Diffuse Malignant Peritoneal Mesothelioma

A series of 22 derivatives of the [1,2]oxazolo[5,4-e]isoindole system were synthesized through an efficient and versatile procedure that involves the annelation of the [1,2]oxazole moiety to the isoindole ring, producing derivatives with a wide substitution pattern. The structure-activity relationship indicates that the N-4-methoxybenzyl group appears crucial for potent activity. In addition, the presence of a 6-phenyl moiety is important and the best activity is reached with a 3,4,5-trimethoxy substituent. The most active compound, bearing both the structural features, was able to inhibit tumor cell proliferation at nanomolar concentrations when tested against the full NCI human tumor cell line panel. Interestingly, this compound was effective in reducing in vitro and in vivo cell growth, impairing cell cycle progression and inducing apoptosis, as a consequence of the inhibition of tubulin polymerization, in experimental models of diffuse malignant peritoneal mesothelioma (DMPM), a rapidly lethal disease, poorly responsive to conventional therapeutic strategies.

Diffuse malignant peritoneal mesothelioma: Evaluation of systemic chemotherapy with comprehensive treatment through the RENAPE Database: Multi-Institutional Retrospective Study

PURPOSE

Diffuse malignant peritoneal mesothelioma (DMPM) is a severe disease with mainly locoregional evolution. Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) is the reported treatment with the longest survival. The aim of this study was to evaluate the impact of perioperative systemic chemotherapy strategies on survival and postoperative outcomes in patients with DMPM treated with curative intent with CRS-HIPEC, using a multi-institutional database: the French RENAPE network.

PATIENTS AND METHODS

From 1991 to 2014, 126 DMPM patients underwent CRS-HIPEC at 20 tertiary centres. The population was divided into four groups according to perioperative treatment: only neoadjuvant chemotherapy (NA), only adjuvant chemotherapy (ADJ), perioperative chemotherapy (PO) and no chemotherapy before or after CRS-HIPEC (NoC).

RESULTS

All groups (NA: n = 42; ADJ: n = 16; PO: n = 16; NoC: n = 48) were comparable regarding clinicopathological data and main DMPM prognostic factors. After a median follow-up of 61 months, the 5-year overall survival (OS) was 40%, 67%, 62% and 56% in NA, ADJ, PO and NoC groups, respectively (P = 0.049). Major complications occurred for 41%, 45%, 35% and 41% of patients from NA, ADJ, PO and NoC groups, respectively (P = 0.299). In multivariate analysis, NA was independently associated with worse OS (hazard ratio, 2.30; 95% confidence interval, 1.07-4.94; P = 0.033).

CONCLUSION

This retrospective study suggests that adjuvant chemotherapy may delay recurrence and improve survival and that NA may impact negatively the survival for patients with DMPM who underwent CRS-HIPEC with curative intent. Upfront CRS and HIPEC should be considered when achievable, waiting for stronger level of scientific evidence.

Treatment of peritoneal surface malignancies with hyperthermic intraperitoneal chemotherapy-current perspectives

Peritoneal carcinomatosis (ptc) represents advanced malignant disease and has generally been associated with a grim prognosis. Peritoneal surface malignancy is often the major source of morbidity and mortality; it is of major concern in cancer management. Although ptc is categorized as metastatic disease, it represents a special disease pattern considered to be a locoregional disease limited to the abdominal cavity. The combination of cytoreductive surgery (crs) and intraoperative hyperthermic intraperitoneal chemotherapy (hipec) has successfully been used as locoregional treatment for selected patients with ptc from gastric, colorectal, and ovarian cancer; with mesothelioma; and with pseudomyxoma peritonei. In the prophylactic setting, hipec can also be used to prevent ptc in high-risk patients, and the first results of the "second-look" approach are promising. Patient selection-in which the risks of perioperative morbidity and mortality, which are analogous to those for any other major gastrointestinal surgery, are assessed-is of utmost importance. Those risks have to be weighed against the anticipated survival benefit, which depends mainly on tumour biology, extent of disease, and probability of achieving complete crs. The present review discusses the principles of crs and hipec, the most significant recent clinical data, and current perspectives concerning the application of this treatment modality in various malignancies. Ongoing trials and future directions are noted. It appears that the combination of crs and hipec is an indispensable tool in the oncologist's armamentarium.

Cytoreductive surgery and intraperitoneal chemotherapy: an evidence-based review-past, present and future

Peritoneal carcinomatosis (PC) has historically been considered a terminal condition with merely palliative treatment achieving a survival rate measured in months. Cytoreductive surgery (CyRS) and intraperitoneal chemotherapy (IPC) have emerged as potentially effective regional treatments with the potential for long-term survival in well-selected patients. The fundamentals of CyRS and IPC are patient selection and complete cytoreduction. Since there is now sufficient evidence for the superiority of CyRS and IPC to systemic chemotherapy alone in a highly select group of patients, surgeons and oncologists should be aware of this modality as a potential benefit for patients with PC. The aim of this report is to highlight cancer-specific evidence in the context of ongoing studies regarding the outcome of this treatment.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy: a review of factors contributing to morbidity and mortality

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is associated with prolonged survival for appropriately selected patients with peritoneal dissemination of abdominal malignancies. CRS and HIPEC has been criticized for perceived high rates of morbidity and mortality. Morbidity and mortality rates of CRS and HIPEC, however, do not appear dissimilar to those of other large abdominal surgeries, particularly when relevant patient and operative factors are accounted for. The risk of morbidity and mortality following this surgery for a given individual can be predicted in part by a variety of patient and operative factors. While strong data are lacking, the limited data that exists on the matter suggests that the independent contribution of the heated intraperitoneal chemotherapy to CRS and HIPEC morbidity is relatively small. A more thorough understanding of the patient and operative factors associated with CRS and HIPEC morbidity and mortality, as well as the specific complications related to the intraperitoneal chemotherapy, can better inform clinicians in multidisciplinary teams and patients alike in the decision-making for this surgery.

Diagnosis and management of patients with malignant peritoneal mesothelioma

Malignant peritoneal mesothelioma (MPM) is a rare neoplastic condition that arises, usually diffusely, from the serosal membranes of the abdominal cavity. MPM represents about 7% to 10% of all mesothelioma diagnoses and this translates into approximately 800 cases per year in the United States. The disease has variable tumor biology but progression, when it occurs, is almost always within the abdominal cavity. Although many patients can be successfully treated at initial presentation, the disease is almost always fatal in time. It afflicts men and women almost equally and the median age at presentation is 50 years. The diagnosis is made when a diffuse malignant process within the abdominal cavity is observed and a tissue sample reveals the characteristic histopathology and immunohistochemical profile of mesothelioma. Initial staging is usually via a cross sectional imaging study of the abdomen and pelvis making sure that the lower thorax is also assessed. If the disease burden and distribution is favorable then operative exploration, cytoreduction, and hyperthermic intraperitoneal chemotherapy (HIPEC) are considered first line treatment in selected patients. Systemic pemetrexed and cisplatin (or gemcitabine) have modest response rates that are of limited duration. Research advances with novel systemic or intraperitoneal agents hold promise.

Cytoreductive Surgery Combined with Hyperthermic Intraperitoneal Chemotherapy with Oxaliplatin Increases the Risk of Postoperative Hemorrhagic Complications: Analysis of Predictive Factors

BACKGROUND

Treatment of peritoneal carcinomatosis (PC) using cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is recommended as curative treatment for selected patients. Modalities of HIPEC remain heterogeneous and HIPEC using oxaliplatin (HIPEC-Ox) appears to increase the risk of postoperative hemorrhagic complications (HCs).

OBJECTIVE

The aim of this study was to assess the risk of HCs after CRS combined with HIPEC-Ox versus other drugs, and to determine predictive factors for HCs after HIPEC-Ox.

METHODS

Data from 701 patients included in the National French Registry who were treated with CRS and HIPEC at 24 centers between 1998 and 2007 were used to evaluate the incidence of HCs following HIPEC with or without oxaliplatin. Overall, 771 patients treated with HIPEC-Ox at five French specialty centers were then analyzed to determine factors associated with the occurrence of HCs.

RESULTS

The overall incidence of HCs was 9.8 %. When used with HIPEC, oxaliplatin significantly and independently increased the rate of HCs (15.7 vs. 2.6 % for other drugs; p = 0.004, odds ratio 32.4). Among the 771 patients who underwent HIPEC-Ox, HCs occurred in 14.3 % of patients. The only independent risk factor for HCs was an extended PC with a Peritoneal Cancer Index (PCI) >12 (p = 0.040).

CONCLUSION

HIPEC-Ox increases the risk of HCs compared with HIPEC with other drugs. The potential oncologic benefit of oxaliplatin and the risk of HCs should be considered in patients with PC who have a high PCI, as well as in at-risk patients.

Outcomes of Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Peritoneal Mesothelioma: Experience of a Peritoneal Surface Malignancy Center

Diffuse malignant peritoneal mesothelioma (DMPM) is an uncommon malignancy, which can be difficult to treat. Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have evolved as the treatment of choice when complete cytoreduction is to be achieved. This study reports the outcomes of CRS/HIPEC for peritoneal mesothelioma performed in a center for peritoneal surface malignancy. A retrospective analysis of a prospective database of 389 CRS/ HIPEC procedures identified 23 patients who underwent CRS/HIPEC for DMPM from 1999 to 2014. Gender, age at diagnosis, age at surgery, previous surgeries, follow-up time, peritoneal cancer index (PCI) score, completeness of cytoreduction (CC), pathology, and overall survival (OS) were analyzed. The univariate analysis was used to determine the prognostic value of age, gender, neoadjuvant chemotherapy, histopathology of the tumor, PCI, CC, and lymph node status on survival. Mean follow-up time from surgery was 31 months (range = 0.5–124). The median PCI score was 28, and 77 per cent had PCI ≥20. CC 0–1 was achieved in 65 per cent of cases. One- and 5-year actuarial OS rates from diagnosis were 86 per cent and 60 per cent, respectively. One- and 5-year actuarial OS from HIPEC was 70 per cent and 64 per cent, respectively. The univariate analysis showed that the CC was the only significant prognostic factor. Patients with DMPM may achieve long-term survival when treated with CRS/HIPEC. The CC is the most significant prognostic factor for long-term survival.

The Role of Ki-67 and Pre-cytoreduction Parameters in Selecting Diffuse Malignant Peritoneal Mesothelioma (DMPM) Patients for Cytoreductive Surgery (CRS) and Hyperthermic Intraperitoneal Chemotherapy (HIPEC)

BACKGROUND

We conducted a prognostic analysis of preoperative parameters and Ki-67 determination to develop selection criteria for cytoreductive surgery (CRS) and HIPEC in patients with diffuse malignant peritoneal mesothelioma (DMPM).

METHODS

DMPM patients treated with CRS and HIPEC at NCI of Milan participated in this study. Multivariate analysis was conducted using Cox proportional hazard model and conditional inference tree method to select independent predictors of overall survival (OS) from the followings pre-cytoreduction parameters: age, sex, ECOG performance status, Charlson comorbidity index, previous systemic chemotherapy, CA-125, histological subtype (epithelioid vs. biphasic/sarcomatoid), Ki-67 (determined with immunohistochemistry), and peritoneal cancer index (PCI).

RESULTS

A total of 117 patients (male/female: 67/50) with median age of 60.5 (range 22-75) years were included. Eighty-three patients had ECOG performance status = 0, median Charlson comorbidity index was 4 (range 2-9), and 102 cases had epithelioid subtype. Median Ki-67 was 5 % (range 1-60). Ninety-four (80.3 %) cases were optimally cytoreduced. The Cox analysis identified Ki-67, PCI, and histological subtype as independent prognosticators of OS. Conditional inference tree method identified three prognostic subsets: (I) Ki-67 ≤ 9 %; (II) Ki-67 > 9 % and PCI ≤ 17; and (III) Ki-67 > 9 % and PCI > 17. The median OS for subsets I, II, and III were, 86.6, 63.2, and 10.3 months, respectively.

CONCLUSIONS

Ki-67 is a powerful prognosticator that allows, along with PCI, and histological subtype, a good prediction of OS in patients with DMPM. Patients with Ki-67 > 9 % and PCI > 17 are unlikely to benefit from the procedure and should be considered for other treatment protocols.