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

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.

Impact of centralization of care for malignant peritoneal mesothelioma: A historical cohort study from the Dutch mesothelioma expert centers

BACKGROUND

Malignant peritoneal mesothelioma (MPM) is a rare and aggressive cancer that has a poor prognosis. An earlier population-based study found that the majority of Dutch patients do not receive anti-cancer treatment. In 2015, Dutch Malignant Mesothelioma care was centralized in two expert centers. We reviewed treatment patterns at these centers, to assess the impact of centralization of MPM care in the Netherlands.

METHODS

Data from all patients referred to the Dutch MPM expert centers from 2014 to 2020, were retrospectively collected. Descriptive statistics regarding referrals, patient and tumor characteristics, and treatment patterns were provided. Population-based incidence rates were provided by the Netherlands Cancer Registry.

RESULTS

From 2014 to 2020, 78 patients were referred to the Dutch Mesothelioma expert centers, of whom 32 were female (41%). From 2014 to 2017, 27 patients were referred, whereas 51 patients were referred from 2018 to 2020. This represents about 24% and 61% of the estimated population incidence, respectively. Treatment patterns were comparable between both periods. Between 2014 and 2018, 33% of patients underwent surgery, 44% systemic therapy, and 22% received best supportive care (BSC), while this was 29%, 37%, and 33% respectively from 2018 to 2020.

CONCLUSION

Centralization of care for patients with MPM resulted in an increase of annual referrals to the Dutch mesothelioma expert centers. While population-based incidence did not change during the study period, the absolute number of patients receiving treatment at our centers did increase. This might be considered a first important step towards better treatment for patients with this fatal disease.

Malignant peritoneal mesothelioma with massive ascites as the first symptom: A case report

BACKGROUND

Malignant peritoneal mesothelioma (MPM) is an extremely rare tumor with nonspecific clinical manifestations, which is extremely difficult to diagnose. Herein, we reported a case of MPM in the abdominal cavity with massive short-term ascites as the first symptom.

CASE SUMMARY

A 65-year-old woman presented to the hospital with abdominal pain, distention, and shortness of breath that persisted for 15 d. The serum CA-125 level was 1075 U/mL. The abdominal computed tomography showed massive ascites and no obvious tumor lesions. The pathological examination of the ascitic fluid showed numerous heterotypic cells with some papillary structures. The immunohistochemistry and fluorescence in situ hybridization showed the deletion of CDX2 (-), WT-1 (-), Ki-67 (about 10% +), CEA (-), Glut-1 (+++), desmin (-), PD-L1 (-), and CDKN2A (P16). The final diagnosis was MPM. The patient refused tumor cytoreductive surgery and received two cycles of cisplatin plus pemetrexed bidirectional chemotherapy. In the second cycle, she received an additional cycle of hyperthermic intraperitoneal chemotherapy and immune checkpoint inhibitor therapy due to massive recalcitrant ascites. She died of disease progression 2 mo after diagnosis.

CONCLUSION

In case of massive unexplained ascites, the possibility of MPM should not be excluded to avoid misdiagnosis and delay in treatment.

Primary and metastatic peritoneal surface malignancies

Peritoneal surface malignancies comprise a heterogeneous group of primary tumours, including peritoneal mesothelioma, and peritoneal metastases of other tumours, including ovarian, gastric, colorectal, appendicular or pancreatic cancers. The pathophysiology of peritoneal malignancy is complex and not fully understood. The two main hypotheses are the transformation of mesothelial cells (peritoneal primary tumour) and shedding of cells from a primary tumour with implantation of cells in the peritoneal cavity (peritoneal metastasis). Diagnosis is challenging and often requires modern imaging and interventional techniques, including surgical exploration. In the past decade, new treatments and multimodal strategies helped to improve patient survival and quality of life and the premise that peritoneal malignancies are fatal diseases has been dismissed as management strategies, including complete cytoreductive surgery embedded in perioperative systemic chemotherapy, can provide cure in selected patients. Furthermore, intraperitoneal chemotherapy has become an important part of combination treatments. Improving locoregional treatment delivery to enhance penetration to tumour nodules and reduce systemic uptake is one of the most active research areas. The current main challenges involve not only offering the best treatment option and developing intraperitoneal therapies that are equivalent to current systemic therapies but also defining the optimal treatment sequence according to primary tumour, disease extent and patient preferences. New imaging modalities, less invasive surgery, nanomedicines and targeted therapies are the basis for a new era of intraperitoneal therapy and are beginning to show encouraging outcomes.

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.

In-Hospital Mortality and Complication Rates According to Health Insurance Data in Patients Undergoing Hyperthermic Intraperitoneal Chemotherapy for Peritoneal Surface Malignancies in Germany

BACKGROUND

Morbidity and in-hospital mortality rates of patients undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in Germany are not known.

METHODS

From 2009 to 2018 all patients undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in Germany were retrospectively analyzed regarding morbidity and in-hospital mortality rates according to nationwide hospital billing data based on diagnosis-related groups (DRG). The "failure to rescue" (FTR) index, characterizing patients who died after severe but potentially manageable complications, was calculated.

RESULTS

In total, 8463 patients were included and analyzed. Female sex predominated (1.5:1). Colonic origin of peritoneal metastasis was highest throughout all years, reaching its highest level in 2017 (55%; n = 563) and its lowest level in 2012 (40%; n = 349). Median length of hospital stay reached its maximum in 2017 at 23.9 days and its minimum in 2010 at 22.0 days. Analysis of the total FTR index showed a noticeable improvement over the years, reaching its lowest values in 2017 (9.8%) and 2018 (8.8%). The FTR index for sepsis, peritonitis, and pulmonary complications significantly improved over time. Of the 8463 included patients, 290 died during hospital stay, reflecting an in-hospital mortality rate of 3.4%.

CONCLUSION

In-hospital mortality after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy is reasonably low compared with other surgical procedures. The improvement in the FTR index reflects efforts to centralize treatment at specialized high-volume centers.

[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.

Bidirectional treatment of peritoneal metastasis with Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC) and systemic chemotherapy: a systematic review

Background

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is used in the palliative treatment of peritoneal metastasis. The combination of intraperitoneal and systemic chemotherapy seems rational, and the aim of this systematic review was to compare PIPAC directed monotherapy with a bidirectional treatment approach (PIPAC in combination with systemic chemotherapy). Main outcomes were survival and quality of life.

Methods

A systematic literature search in Medline, Embase, Cochrane and the “Pleura and Peritoneum” was conducted and analyzed according to PRISMA guidelines. Studies in English reporting on bidirectional treatment with PIPAC and systemic chemotherapy and published before April 2019 were included.

Results

Twelve studies with a total of 386 patients were included. None were specifically designed to compare mono- versus bidirectional treatment, but 44% of the patients received bidirectional treatment. This was more frequent in women (non-gynecological cancers) and one-third of the bidirectional treated patients had received no prior chemotherapy. Data from the included studies provided no conclusions regarding survival or quality of life.

Conclusion

Bidirectional treatment with PIPAC and systemic chemotherapy is practised and feasible, and some patients are enrolled having received no prior systemic chemotherapy for their PM.

The difficulty in drawing any conclusions based on this systematic review has highlighted the urgent need to improve and standardize reports on PIPAC directed therapy. We have, therefore, constructed a list of items to be considered when reporting on clinical PIPAC research.

Trial registration

International Prospective Register of Systematic Reviews, PROSPERO. Registration number: 90352, March 5, 2018.

Upfront debulking surgery versus interval debulking surgery for advanced tubo-ovarian high-grade serous carcinoma and diffuse peritoneal metastases treated with peritonectomy procedures plus HIPEC

BACKGROUND

Whether patients with advanced tubo-ovarian high-grade serous cancer (HGSC) fare better after upfront debulking surgery (UDS) or neoadjuvant chemotherapy with interval debulking surgery (NACT-IDS) remains controversial.

METHODS

We studied patients with HGSC who underwent UDS or NACT-IDS between July 2000 and December 2015, with peritonectomy procedures combined with hyperthermic intraperitoneal chemotherapy (HIPEC). Clinical reports were included peritoneal cancer index (PCI), NACT responses, surgical complexity score (SCS), completeness of cytoreduction (CC), complete follow-up with timing, site, and treatment of recurrence. Outcome measures were morbidity, progression-free survival (PFS), PFS2, and overall survival during a mean 5-year follow-up.

RESULTS

A total of 34 patients (23.6%) underwent UDS and 110 (76.4%) NACT-IDS both combined with HIPEC. At a median 66.3-month follow-up, patients who underwent UDS or NACT-IDS had similar outcomes. NACT subgroup responses correlated with PCI, SCS, morbidity, and CC. Patients who underwent UDS had lower recurrence rates than those who responded partly or poorly to NACT (PFS, P < .04; PFS2, P < .01). Despite HIPEC, the peritoneal disease recurred in 42.5% of the overall patients.

CONCLUSION

In patients with primary HGSC who undergo UDS or NACT-IDS, despite similar outcomes, peritonectomy procedures combined with HIPEC seem unable to prevent peritoneal recurrence.

MESOTIP: Phase II multicenter randomized trial evaluating the association of PIPAC and systemic chemotherapy vs. systemic chemotherapy alone as 1st-line treatment of malignant peritoneal mesothelioma

Background

Malignant peritoneal mesothelioma (MPM) is a rare tumoral disease characterized by the diffuse involvement of the peritoneal serosa. The standard frontline treatment of MPM is cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC) unless the peritoneal disease is considered unresectable. For unresectable patients the standard frontline treatment is a combination of cisplatin and pemetrexed but the prognosis remains ominous with only 13 months of overall survival (OS).

Methods

The proposed study is a multicenter randomized non-comparative study evaluating the association of Pressurized Intra-Peritoneal Aerosol Chemotherapy (PIPAC) and systemic chemotherapy vs. systemic chemotherapy alone as first-line treatment of MPM. Patients will be randomized with a 2:1 ratio using a minimization technique. Sixty-six patients have to be enrolled. Stratification will be performed according to histology (epithelioid vs. sarcomatoid and biphasic), presence of extraperitoneal disease and center. Primary objective is OS and secondary objectives include progression-free survival (PFS), safety, compliance, feasibility, conversion to resectability, histological response to treatment and quality of life.

Conclusions

We expect to show that intensification of the first line treatment with PIPAC for initially unresectable MPM patients increases OS.

Trial registration

Prospective study. Clinicaltrials.gov: NCT03574493 EudraCT: 2019–001515-23.

Bidirectional chemotherapy allowing surgery and HIPEC for malignant peritoneal mesothelioma

Background

This case report aims to describe the impact of the bidirectional chemotherapy (BDC) on resecability for initially unresectable malignant peritoneal mesothelioma (MPM).

Methods

We report a case of 55-year-old male with the diagnosis of initially unresecable MPM. The BDC combined intravenous (IV) chemotherapy (Cisplatin–Pemetrexed) and intra peritoneal (IP) chemotherapy (Cisplatin). The response to chemotherapy was assessed by CT – scan and laparoscopy.

Results

Initial evaluation classed the disease as unresecable with PCI at 39. At the reevaluation, CT – scan and laparoscopy showed a macroscopic response, allowing surgery consisting of cytoreductive surgery and hyperthermic intra peritoneal chemotherapy (Doxorubicin and Cisplatin).

Conclusions

BDC (IV and IP) has promising results and allows to undergo surgery for selected patients with borderline or initially unresectable MPM.

Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy for peritoneal mesothelioma: patient selection and special considerations

Malignant peritoneal mesothelioma (MPM) is a rare, aggressive malignancy that typically presents with vague symptoms, ascites, and/or diffuse peritoneal studding. Despite findings of advanced disease within the peritoneal cavity, spread beyond the abdomen is uncommon. Although advances in systemic chemotherapy have been made, cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) remain the mainstay of treatment. Median overall survival of approximately 50 months with CRS/HIPEC has been demonstrated, with age, gender, histologic subtype, peritoneal carcinomatosis index, comorbidities, nodal and extra-abdominal metastases, and completeness of cytoreduction all playing a role in prognosis. In patients with refractory malignant ascites and unresectable disease, complete resolution of ascites and improvement in quality of life have been demonstrated with palliative HIPEC. In appropriately selected patients, CRS/HIPEC plays a critical role in the treatment and palliation of MPM.

Morbidity and Mortality Rates Following Cytoreductive Surgery Combined With Hyperthermic Intraperitoneal Chemotherapy Compared With Other High-Risk Surgical Oncology Procedures

IMPORTANCE

Currently, rates of referral of patients with peritoneal metastasis in the United States who qualify for cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) are low, in part because of the misperception of high morbidity and mortality rates. However, patients requiring major gastrointestinal surgical procedures with similar complication rates are routinely referred.

OBJECTIVE

To evaluate the relative safety of CRS/HIPEC.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study of 34 114 patients who underwent CRS/HIPEC, right lobe hepatectomy, trisegmental hepatectomy, pancreaticoduodenectomy, and esophagectomy between January 1, 2005, and December 31, 2015, included in the American College of Surgeons National Surgical Quality Improvement Project (NSQIP) database. Data analysis was performed in 2018.

MAIN OUTCOMES AND MEASURES

Data from the NSQIP database were used to compare perioperative and 30-day postoperative morbidity and mortality rates of CRS/HIPEC (1822 patients) with other, well-accepted, high-risk surgical oncology procedures: right lobe hepatectomy (5109 patients), trisegmental hepatectomy (2449 patients), pancreaticoduodenectomy (Whipple) (16 793 patients), and esophagectomy (7941 patients).

RESULTS

For 34 114 patients, median (interquartile range [IQR]) age was 63 (55-71) years and 42% were female. Patients undergoing CRS/HIPEC tended to be younger, with a median age of 57 years, and esophagectomy had the highest median (IQR) American Society of Anesthesiologists classification (3 [3-3]). When compared with CRS/HIPEC, higher complication rates were reported in the following categories: (1) superficial incisional infection in Whipple and esophagectomy (5.4% [95% CI, 4.4%-6.4%] vs 9.7% [95% CI, 9.3%-10.1%] and 7.2% [95% CI, 6.6%-7.8%], respectively; P < .001); (2) deep incisional infection in Whipple (1.7% [95% CI, 1.1%-2.3%] vs 2.7% [95% CI, 2.5%-2.9%]; P < .01); (3) organ space infection in right lobe hepatectomy (7.2% [95% CI, 6.0%-8.4%] vs 9.0% [95% CI, 8.2%-9.8%]; P = .02), trisegmental hepatectomy (12.4% [95% CI, 11.1%-13.7%]; P < .001), and Whipple (12.9% [95% CI, 12.4%-13.4%]; P < .001); and (4) return to the operating room for esophagectomy (6.8% [95% CI, 5.6%-8.0%] vs 14.4% [95% CI, 13.6%-15.2%]; P < .001). Median (IQR) length of hospital stay was lower in CRS/HIPEC (8 [5-11] days) than Whipple (10 [7-15] days) and esophagectomy (10 [8-16] days) (P < .001). Overall 30-day mortality was lower in CRS/HIPEC (1.1%; 95% CI, 0.6%-1.6%) compared with Whipple (2.5%; 95% CI, 2.3%-2.7%), right lobe hepatectomy (2.9%; 95% CI, 2.4%-3.4%), esophagectomy (3.0%; 95% CI, 2.6%-3.4%), and trisegmental hepatectomy (3.9%; 95% CI, 3.1%-4.7%) (P < .001).

CONCLUSIONS AND RELEVANCE

Comparative analysis revealed CRS/HIPEC to be safe, often safer across the spectrum of NSQIP safety metrics when compared with similar-risk oncologic procedures. Patient selection was important in achieving observed outcomes. High complication rates are a misperception from early CRS/HIPEC experience and should no longer deter referral of patients to experienced centers or impede clinical trial development in the United States.

Malignant Peritoneal Mesothelioma: National Practice Patterns, Outcomes, and Predictors of Survival

PURPOSE

This study of a large, contemporary national database evaluated management patterns, outcomes, and prognostic factors of malignant peritoneal mesothelioma (MPM) in the USA.

METHODS

The National Cancer Data Base was queried for newly diagnosed nonmetastatic MPM. Patients were divided into five cohorts: observation, chemotherapy alone, cytoreductive surgery (CRS) alone, CRS/chemo [referring to any non-hyperthermic intraperitoneal chemotherapy (HIPEC) chemotherapy], and CRS/HIPEC. Statistics included multivariable logistic regression, Kaplan-Meier analysis, and Cox proportional hazards modeling.

RESULTS

Of 1514 patients, 379 (25%) underwent observation, 370 (24%) received chemotherapy only, 197 (13%) CRS alone, 352 (23%) CRS/chemo, and 216 (14%) CRS/HIPEC. No major temporal trends in management were noted. Factors predictive of CRS administration included younger age, female gender, insurance status, residence in educated areas, living farther from treating institutions, and treatment at academic centers (p < 0.05 for all). Compared with epithelioid histology, those with sarcomatoid and biphasic histology were less and more likely to undergo CRS, respectively (p < 0.05 for both). In all CRS patients, 30- and 90-day mortality rates were 0.8 and 1.2%, respectively. At median follow-up of 50 months, median OS in the respective groups was 6, 17, 21, 52, and 61 months (p < 0.001). Poor prognostic factors included advanced age, male gender, uninsured/Medicaid insurance, and sarcomatoid/biphasic histology (p < 0.05 for all).

CONCLUSIONS

In the USA, MPM is treated using a wide variety of strategies. Many factors impact the type of treatment delivered, including age, sociodemographics, geography, histology, and facility type. Although these data do not imply causation, combined-modality management seems associated with the longest OS.