Peritoneal Mesothelioma

Peritoneal Mesothelioma

Peritoneal Mesothelioma
ICD-10 Code	C45.1
Also Known As	Malignant peritoneal mesothelioma (MPeM), abdominal mesothelioma
Location	Peritoneum (abdominal lining)
% of All Mesothelioma	10–30% (~20% most cited)
US Cases Per Year	~300–800 (est. 315 avg.)
Median Age	63 years
Male:Female Ratio	~1:1 (near equal)
Primary Cause	Asbestos (33–50% of cases)
Latency Period	~20 years (shorter than pleural)
Standard Treatment	CRS + HIPEC
Median OS (CRS+HIPEC)	53 months
5-Year Survival	40–70% (CRS+HIPEC)
Staging System	PCI (Peritoneal Cancer Index)

Peritoneal mesothelioma is a rare and aggressive cancer that develops in the peritoneum — the thin membrane lining the abdominal cavity and covering the abdominal organs. It is the second most common form of mesothelioma, accounting for approximately 10–30% of all cases (most commonly cited as ~20%). The disease is diagnosed in an estimated 300–800 individuals annually in the United States, with an incidence rate of 0.11 per 100,000. Unlike pleural mesothelioma, which affects the lung lining and overwhelmingly strikes older men with occupational asbestos exposure, peritoneal mesothelioma has a nearly equal male-to-female ratio, a younger median age at diagnosis (63 vs. 71 years), and a significantly weaker association with asbestos exposure (33–50% vs. ~80%).

The introduction of cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) has transformed outcomes for this disease. Multi-institutional data demonstrates a median overall survival of 53 months and 5-year survival rates of 40–70% in selected patients — dramatically superior to pleural mesothelioma, where 5-year survival remains approximately 10%. The 2025 Consensus Guidelines recommend a risk-stratified, multidisciplinary approach, with upfront CRS+HIPEC for low-risk disease and systemic therapy for high-risk, unresectable cases.

✅ Key Facts About Peritoneal Mesothelioma

Peritoneal mesothelioma accounts for 10–30% of all mesothelioma cases, with ~300–800 new U.S. cases annually Only 33–50% of patients report known asbestos exposure, compared to ~80% for pleural mesothelioma The Peritoneal Cancer Index (PCI) is the primary staging tool — there is no formal TNM staging system for this disease CRS+HIPEC (cytoreductive surgery + heated intraperitoneal chemotherapy) is the standard of care, with median survival of 53 months Patients achieving complete cytoreduction (CC-0) have median survival of 94 months — nearly 8 years Epithelioid subtype (56–75% of cases) carries the best prognosis, with 5-year survival of 64.5% after CRS+HIPEC The male-to-female ratio is approximately 1:1, unlike the 4:1 male predominance in pleural mesothelioma Germline BAP1 mutations are found in 4.4–6% of mesothelioma patients, with peritoneal cases disproportionately represented Misdiagnosis is common — approximately one-third of women are initially misdiagnosed with ovarian cancer Over $30 billion remains in asbestos trust funds, and veterans with mesothelioma qualify for 100% VA disability

What Is Peritoneal Mesothelioma?

Peritoneal mesothelioma arises from the mesothelial cells that line the peritoneal cavity — a thin, protective membrane that covers both the abdominal wall (parietal peritoneum) and the surface of abdominal organs including the liver, stomach, intestines, and spleen (visceral peritoneum). The peritoneum normally produces a small amount of lubricating fluid that allows organs to move smoothly against one another. When malignant mesothelioma develops in this tissue, it typically spreads diffusely across the peritoneal surfaces rather than forming a single discrete mass. This pattern of diffuse growth throughout the abdomen, rather than deep invasion into organs, is a defining characteristic that distinguishes peritoneal mesothelioma from many other abdominal malignancies and provides the rationale for the locoregional treatment approach of CRS+HIPEC.

A critical clinical distinction exists between malignant peritoneal mesothelioma and two benign peritoneal conditions. Well-differentiated papillary mesothelioma (WDPM) is now recognized as a genetically distinct entity from malignant mesothelioma, defined by mutually exclusive mutations in TRAF7 and CDC42 — mutations that are absent in malignant mesothelioma. All WDPM cases demonstrate intact BAP1 expression by immunohistochemistry, in contrast to malignant mesothelioma where BAP1 loss occurs in approximately half of cases. The 2025 consensus guidelines recommend observation for WDPM, with intervention reserved for symptomatic, recurrent, diffuse, or microinvasive disease. Multicystic peritoneal mesothelioma is another benign variant consisting of small cysts composed of mesothelial epithelium with bland cuboidal cells, distinguishable from malignant disease by its lack of invasion and simple architectural patterns.

How Common Is Peritoneal Mesothelioma?

The Centers for Disease Control and Prevention (CDC) reported 2,669 total mesothelioma cases in the United States in 2022. Of these, peritoneal mesothelioma accounts for an estimated 315 average yearly cases at an incidence rate of 0.11 per 100,000, compared to pleural mesothelioma's rate of 0.53 per 100,000 (approximately 2,442 yearly cases). Other sources cite the annual figure at 300–800 new peritoneal cases, reflecting variability in diagnostic coding and reporting practices.

While the incidence of pleural mesothelioma in males has shown a significant decline since peaking in the mid-1990s — reflecting reduced asbestos exposure following workplace bans in the 1970s–1980s — peritoneal mesothelioma incidence in both men and women has remained stable over the same period. This stability despite declining occupational asbestos exposure further supports the hypothesis that non-asbestos factors, including genetic predisposition and other environmental exposures, play a more prominent role in peritoneal disease than in pleural disease.

The epidemiological profile of peritoneal mesothelioma differs markedly from pleural mesothelioma in several ways. The male-to-female ratio is approximately 1:1 for peritoneal cases, compared to the strong 4:1 male predominance seen in pleural mesothelioma. The median age at diagnosis is 63 years — notably younger than the 71-year median for pleural mesothelioma — and peritoneal cases include a higher proportion of younger patients, which is consistent with genetic predisposition playing a greater role. In U.S. SEER data, 7% of male mesothelioma and 18% of female mesothelioma are diagnosed in the peritoneum, reflecting the higher proportion of peritoneal disease among women.

Projections estimate approximately 15,000 peritoneal mesothelioma cases will be diagnosed in the United States between 2005 and 2050. The highest overall mesothelioma rates globally are reported in the United Kingdom, Australia, and New Zealand, while the United States has mid-range incidence at approximately 1.94 per 100,000 for men and 0.41 per 100,000 for women.

What Are the Signs and Symptoms?

Peritoneal mesothelioma symptoms are characteristically vague and nonspecific, closely mimicking common gastrointestinal conditions. This non-specific presentation is a major reason the disease is frequently misdiagnosed or diagnosed at an advanced stage.

Symptom	Frequency
Abdominal distension / ascites	30–80%
Abdominal pain	27–58%
Ascites on imaging	60–100%
Weight loss	Common
Early satiety / nausea	Common
Bowel changes	Variable
New onset hernia	Rare
Fever of unknown origin	Rare

The average time from symptom onset to diagnosis is approximately 4–6 months, though this interval is frequently longer given the vague nature of early symptoms. Nearly all patients have some degree of peritoneal spread at the time of diagnosis. Approximately one-third of women with peritoneal mesothelioma are initially misdiagnosed with ovarian cancer, primarily because both conditions can elevate serum CA-125 levels and present with ascites and abdominal masses. The disease is also commonly confused with appendiceal cancer, primary peritoneal serous carcinoma, colorectal adenocarcinoma with peritoneal spread, and tuberculous peritonitis.

"Peritoneal mesothelioma presents unique diagnostic challenges because its symptoms overlap with so many common abdominal conditions. When a patient presents with unexplained ascites and abdominal pain, especially if there is any history of asbestos exposure, mesothelioma should be part of the differential diagnosis."

— Paul Danziger, Founding Partner, Danziger & De Llano

How Is Peritoneal Mesothelioma Diagnosed?

Imaging

CT of the abdomen and pelvis with intravenous contrast is the accepted first-line imaging modality for peritoneal mesothelioma. Characteristic findings include solid, heterogeneous soft-tissue masses with irregular margins that enhance with contrast; omental caking and thickening; peritoneal nodularity; mesenteric involvement; ascites; and scalloping of intra-abdominal organs. The disease tends to be more expansive than infiltrative, without a single identifiable primary site.

PET-CT can be useful for identifying biopsy sites and detecting occult extra-abdominal disease. FDG-avid results were found in 91.7% of peritoneal mesothelioma patients in one large series. MRI with diffusion-weighted and dynamic gadolinium-enhanced sequences may more accurately estimate peritoneal disease burden, but its diagnostic utility is not yet well-defined for routine clinical use.

Tissue Diagnosis

Definitive diagnosis requires histopathological evaluation of tissue. Cytological analysis of ascitic fluid has a low diagnostic yield for mesothelioma specifically, owing to the low number of malignant cells and the significant cytological diversity of mesothelioma tumor cells. The preferred biopsy approaches include CT-guided core-needle biopsy and laparoscopic biopsy — the latter is often preferred because it allows direct visualization of the peritoneal cavity, assessment of disease extent through PCI scoring, and tissue sampling.

Immunohistochemistry (IHC)

The immunohistochemistry panel used to confirm peritoneal mesothelioma and distinguish it from other peritoneal cancers includes:

Marker Type	Markers	Expected Result
Positive mesothelial markers	Calretinin, WT-1, CK5/6, D2-40, mesothelin	Positive in mesothelioma
Negative carcinoma markers	CEA, Ber-EP4, PAX8, B72.3, TTF-1	Negative in mesothelioma
BAP1	Loss of nuclear staining	Lost in ~55–67% of peritoneal mesothelioma

BAP1 loss occurs in approximately 55% of peritoneal mesothelioma and has 100% specificity for distinguishing malignant from benign mesothelial proliferations — meaning that if BAP1 is lost, the proliferation is malignant. However, BAP1 retention does not exclude mesothelioma. When differentiating from ovarian cancer specifically, PAX8 negativity is a useful marker, as PAX8 is typically positive in ovarian carcinoma but negative in mesothelioma.

Biomarkers

Currently available serum biomarkers have limited standalone diagnostic utility for peritoneal mesothelioma. Serum CA-125 is frequently elevated but nonspecific — it is also elevated in ovarian cancer, peritoneal inflammation, and endometriosis. CA-125 is more useful for surveillance after treatment, as levels normalize after successful therapy. Serum mesothelin-related protein (SMRP) has a sensitivity of approximately 60% — insufficient for standalone diagnosis but potentially useful for monitoring. No biomarker is currently validated for screening or early detection of peritoneal mesothelioma.

What Are the Histological Subtypes?

Peritoneal mesothelioma is classified by the World Health Organization (WHO) into three histological subtypes, which are critical determinants of prognosis and treatment eligibility:

Subtype	Frequency	Characteristics	Prognosis
Epithelioid	56–75%	Cells resembling normal mesothelial cells in tubulopapillary/trabecular patterns; uncommon mitoses	Best — median OS 55 months
Biphasic (Mixed)	13–25%	Contains both epithelioid and sarcomatoid components (each ≥10%)	Intermediate — median OS ~13 months
Sarcomatoid	Rare to 31%	Tightly packed spindle cells; sometimes with malignant osteoid, chondroid, or muscular elements	Worst — measured in months

The epithelioid subtype is the most common and carries the most favorable prognosis. Patients with epithelioid peritoneal mesothelioma who achieve complete cytoreduction (CC-0) through CRS+HIPEC have demonstrated a 5-year survival rate of 64.5%. The higher proportion of epithelioid tumors in peritoneal mesothelioma compared to pleural mesothelioma is one factor contributing to the generally better outcomes seen in peritoneal disease. The percentage breakdown varies across studies — the higher epithelioid proportion (75%) comes from larger series at tertiary surgical centers, while the 56% figure reflects more recent literature reviews. This discrepancy likely reflects referral and selection bias at specialized centers.

How Is Peritoneal Mesothelioma Staged?

No Formal TNM Staging

A critical distinction from pleural mesothelioma and most other solid tumors is that there is no widely adopted formal TNM staging system for peritoneal mesothelioma. The rarity of distant metastases and the difficulty in distinguishing primary tumor extent from regional spread make traditional staging paradigms poorly suited to this disease. Instead, disease assessment and treatment planning rely primarily on the Peritoneal Cancer Index (PCI).

Peritoneal Cancer Index (PCI)

The PCI is the primary tool for disease assessment in peritoneal mesothelioma and is assessed either by preoperative imaging (CT-based) or at the time of surgical exploration:

The peritoneal cavity is divided into 13 regions — 9 abdominopelvic regions (numbered 0–8) and 4 small bowel regions (numbered 9–12). Each region receives a Lesion Size score of 0–3: 0 = no visible disease, 1 = lesions ≤0.5 cm, 2 = lesions 0.5–5 cm, 3 = lesions ≥5 cm or bowel wall invasion. The maximum composite PCI score is 39.

PCI Range	Disease Burden	Median Survival	Treatment Implication
PCI 0–10	Low	87% 5-year survival	Excellent CRS+HIPEC candidate
PCI 11–19	Moderate	43 months median	CRS+HIPEC with careful evaluation
PCI 20–30	High	6 months median	Consider neoadjuvant therapy first
PCI 31–39	Very high	Poor	Systemic therapy; CRS unlikely feasible

A PCI score ≥20 is generally associated with lower likelihood of successful complete cytoreduction and inferior outcomes. The Peritoneal Surface Oncology Group International (PSOGI) has proposed a formal staging system using PCI as the T component, dividing patients into Stage I (PCI 0–10), Stage II (PCI 11–30), and Stage III (PCI 31–39 or any N+/M+), with 5-year survival rates of 87%, 53%, and 29%, respectively.

Completeness of Cytoreduction (CC) Score

The CC score is assessed at the time of surgery and is one of the most consistently significant prognostic factors:

CC Score	Definition	Median Survival
CC-0	No visible residual disease	94 months
CC-1	Residual nodules ≤2.5 mm	67 months
CC-2	Residual nodules 2.5 mm–2.5 cm	40 months
CC-3	Residual nodules >2.5 cm	12 months

The dramatic difference in survival between CC-0 (94 months) and CC-3 (12 months) underscores why achieving complete cytoreduction is the single most important surgical goal in peritoneal mesothelioma treatment.

What Are the Treatment Options?

Cytoreductive Surgery (CRS) + HIPEC

CRS combined with HIPEC is the landmark, standard-of-care treatment for resectable peritoneal mesothelioma and represents the single most significant therapeutic advance in this disease. This combined approach was pioneered by Paul Sugarbaker at the Washington Cancer Institute and established as the standard of care following NIH and international consensus meetings.

The surgical phase (CRS) aims for complete removal of all visible tumor, which may require parietal peritonectomy, visceral peritonectomy, omentectomy, splenectomy, cholecystectomy, bowel resections, and diaphragmatic stripping. Following maximal cytoreduction, the HIPEC phase delivers heated chemotherapy directly into the abdominal cavity at 41–43°C for approximately 60–90 minutes. The most commonly used drugs are cisplatin (with or without doxorubicin) and mitomycin C.

Study	Patients	Median OS	5-Year OS
Yan et al. 2009 (multi-institutional, 29 centers)	405	53 months	47%
Alexander et al. 2013 (3 US centers)	211	38.4 months	41% (10-yr: 26%)
Baratti/Deraco 2013 (Milan, CC-0 patients)	108	63.2 months	~50% (7-yr cure: 43.6%)
Sugarbaker CRS+HIPEC+NIPEC	29	Not reached at 5 yr	75%
Meta-analysis (20 studies, CC-0/1)	1,047	—	42%

Operative mortality (30-day) ranges from 0–8% at experienced centers, with 1.9% reported in the largest single-institution series. Major complication rates range from 10–45%, including myelosuppression, wound infections, prolonged ileus, bowel obstruction, and fistula formation.

Repeat CRS+HIPEC for peritoneal recurrence (which occurs in approximately 40% of patients) is feasible and yields encouraging results, with median survival of 52.9 months after repeat procedure. Patients undergoing multiple rounds demonstrated median survival of 80 months versus 27.2 months for single-round treatment.

Systemic Chemotherapy

The standard first-line systemic regimen is pemetrexed + cisplatin, validated in the landmark 2003 Vogelzang phase III trial for pleural mesothelioma and extended to peritoneal disease. Peritoneal-specific data from the International Expanded Access Program showed a response rate of approximately 25%, disease control rate of 71.2%, and median survival of 13.1 months with pemetrexed + cisplatin. Pemetrexed + carboplatin is an acceptable alternative with similar efficacy (~24% response rate) and better tolerability for older or frailer patients.

Neoadjuvant chemotherapy before CRS+HIPEC is controversial. A 2016 study found neoadjuvant chemotherapy was independently associated with worse outcomes (5-year OS 40% vs. 56–67% with other approaches), suggesting upfront CRS+HIPEC is preferred when feasible.

Immunotherapy

While the CheckMate 743 trial demonstrated the superiority of nivolumab + ipilimumab for unresectable pleural mesothelioma, its applicability to peritoneal mesothelioma remains uncertain as the trial included mostly pleural patients. However, peritoneal-specific immunotherapy data is emerging. A phase II trial of atezolizumab + bevacizumab in 20 previously-treated peritoneal mesothelioma patients showed a promising 40% objective response rate, 1-year progression-free survival of 61%, and 1-year overall survival of 85%. PD-L1 expression is observed in approximately 50% of peritoneal mesothelioma (vs. 30% in pleural), suggesting peritoneal cases may have favorable immunotherapy biomarker profiles.

A phase II trial (NCT05041062) is currently investigating perioperative nivolumab + ipilimumab specifically for resectable peritoneal mesothelioma, which may help clarify the role of immunotherapy in this disease.

PIPAC: A Promising Emerging Therapy

Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) is a promising minimally invasive technique that delivers aerosolized chemotherapy under pressure into the peritoneal cavity via laparoscopy, achieving superior drug penetration and tissue distribution compared to liquid intraperitoneal chemotherapy.

PIPAC offers several advantages: it is minimally invasive (laparoscopic), repeatable, causes minimal systemic toxicity, and requires only a short hospital stay (median 3 days). The severe complication rate is 6.2%. Patients receiving two or more PIPAC sessions demonstrated median survival of 15–16 months versus 4.7–10.5 months for a single session. Perhaps most significantly, PIPAC has shown the ability to downstage initially unresectable disease — in one series, 50% of initially unresectable patients were subsequently able to undergo complete CRS+HIPEC after neoadjuvant PIPAC, and 81.9% of these converted cases remained disease-free at last follow-up.

Radiation Therapy

Radiation therapy has a very limited role in peritoneal mesothelioma, in contrast to pleural disease where it has established applications. The diffuse nature of peritoneal mesothelioma across the entire peritoneal surface makes targeted radiation impractical without unacceptable toxicity to surrounding organs. Whole abdominal radiation has been largely abandoned due to significant toxicity. Palliative radiation may occasionally be used for symptomatic focal disease.

What Is the Prognosis and Survival Rate?

The prognosis for peritoneal mesothelioma has improved dramatically with the advent of CRS+HIPEC, making it significantly more survivable than pleural mesothelioma when patients are eligible for surgical treatment:

Treatment Setting	Median Survival	5-Year Survival
Untreated / supportive care only	Less than 6–12 months	—
Systemic chemotherapy alone	11–13 months	—
CRS+HIPEC (all patients, multi-institutional)	38–53 months	41–47%
CRS+HIPEC (CC-0, epithelioid, selected)	63–94 months	50–65%
CRS+HIPEC+NIPEC (Sugarbaker protocol)	Not reached at 5 years	75%

The key prognostic factors consistently identified across multiple studies include: completeness of cytoreduction (the single most important factor), histological subtype (epithelioid strongly favorable), PCI score (lower is better), age (younger patients fare better), lymph node involvement (N+ median survival 6–20 months vs. 56–59 months N-), and Ki-67 proliferative index (≤10% correlates with improved survival).

Notably, patients who survive 7 or more years after CRS+HIPEC appear to reach a survival plateau, with 43.6% of patients in the Baratti/Deraco series remaining alive at 7+ years of follow-up — suggesting a potential cure for a substantial minority of patients.

How Does Peritoneal Mesothelioma Compare to Pleural Mesothelioma?

Feature	Peritoneal Mesothelioma	Pleural Mesothelioma
% of all mesothelioma	10–30%	70–85%
Male:Female ratio	~1:1	~4:1
Median age at diagnosis	63 years	71 years
Asbestos exposure	33–50%	~80%
Latency period	~20 years	30–40 years
Standard treatment	CRS + HIPEC	Chemo ± immunotherapy ± surgery
Median OS (treated)	38–53 months (CRS+HIPEC)	12–18 months
5-year survival	40–70% (CRS+HIPEC)	~10%
Staging system	PCI (no formal TNM)	TNM (AJCC 8th Edition)
CDKN2A deletion frequency	25.9%	48.2%

The substantially better survival outcomes for peritoneal mesothelioma compared to pleural mesothelioma are attributable to several factors: the confinement of disease to the peritoneal cavity (allowing effective locoregional treatment), the higher proportion of favorable epithelioid histology, the effectiveness of CRS+HIPEC, and potentially different underlying biology including lower rates of CDKN2A deletions.

How Does Asbestos Cause Peritoneal Mesothelioma?

While asbestos is the established cause of mesothelioma, only 33–50% of peritoneal mesothelioma patients report known prior asbestos exposure, compared to approximately 80% for pleural mesothelioma. Among women specifically, only 23% report asbestos exposure versus 58% of men.

Several pathways have been proposed for how asbestos fibers reach the peritoneal cavity. The ingestion pathway involves swallowed asbestos fibers transiting through the gastrointestinal tract and penetrating to the peritoneal surface — asbestos fibers have been identified in the omentum and mesentery. The translocation pathway involves inhaled fibers being transported via the lymphatic system from the lungs to the peritoneum, supported by findings of pulmonary asbestosis (17%) and pleural plaques (26%) in peritoneal mesothelioma patients. A female genital tract pathway has also been proposed, involving asbestos-contaminated talc reaching the peritoneum via the fallopian tubes.

The significant proportion of cases without identifiable asbestos exposure — sometimes termed the "peritoneal paradox" — is a major area of investigation. Germline BAP1 mutations are found in approximately 4.4–6% of all mesothelioma patients, but peritoneal cases are disproportionately represented (55.6% of germline BAP1-mutation carriers had peritoneal disease). Research estimates that 20–36% of mesotheliomas may be caused by inherited pathogenic mutations in cancer-related genes without asbestos exposure. Other potential non-asbestos causes include prior abdominal radiation exposure, erionite (a fibrous zeolite mineral), chronic peritoneal inflammation, and genetic predisposition involving the Hippo, mTOR, RNA helicase, and p53 pathways.

"Even patients who don't recall direct asbestos exposure may have been exposed through secondary contact — laundering a family member's work clothes, living near an industrial site, or using asbestos-contaminated consumer products. An experienced mesothelioma attorney can investigate exposure history and identify responsible parties that the patient may not have considered."

— Rod De Llano, Founding Partner, Danziger & De Llano

What Compensation Is Available?

Asbestos Trust Funds

Over $30 billion remains available in asbestos trust funds established by bankrupt asbestos manufacturers. These funds provide compensation without requiring a lawsuit. Mesothelioma claimants typically receive the highest disease-level payments among asbestos-related illnesses.

Average trust fund payouts for mesothelioma total $300,000–$400,000 across multiple trusts. Individual trust scheduled values range from $110,000–$350,000 per trust, though actual payouts are reduced by trust-specific payment percentages (typically 5–25% of scheduled value). An experienced attorney will file claims with several trusts simultaneously to maximize total recovery. Trust fund schedules generally classify mesothelioma as the highest disease level regardless of subtype — there is no documented systematic difference in trust fund payments between peritoneal and pleural mesothelioma.

Personal Injury Lawsuits

Average mesothelioma settlements range from $1 million–$1.4 million, while average trial verdicts range from $2.4 million–$20.7 million depending on the source and year of data. Notable peritoneal-specific verdicts include an $82 million Washington jury award for wrongful death from peritoneal mesothelioma caused by auto products asbestos exposure, and an $18 million 2025 Florida jury verdict for peritoneal mesothelioma.

VA Benefits for Veterans

The VA considers mesothelioma 100% disabling, qualifying veterans for the maximum disability compensation rate. For 2026, married veterans with mesothelioma receive $4,158.17 per month in disability compensation. Surviving spouses qualify for VA DIC benefits of $1,653.07 per month. There is no time limit on filing VA claims for mesothelioma.

📞 Free Peritoneal Mesothelioma Case Review If you or a loved one has been diagnosed with peritoneal mesothelioma, the attorneys at Danziger & De Llano can help you explore all compensation options — including trust fund claims, lawsuits, and VA benefits. Contact us at (866) 222-9990 or visit dandell.com for a free, confidential case evaluation.

Free, Confidential Case Evaluation Call (866) 222-9990 or visit dandell.com/contact-us No upfront fees • Experienced representation • National practice

Latest Research and Future Directions

The 2025 Consensus Guidelines for peritoneal mesothelioma management, developed using a Modified Delphi technique with 101 expert participants, represent the most current evidence-based guidance for this rare disease. Key recommendations include a risk-stratification approach (low-risk: upfront CRS+IPCT; intermediate-risk: neoadjuvant therapy then reassess; high-risk: systemic therapy only), emphasis on multidisciplinary evaluation, and surveillance with CT/MRI every 3 months for the first two years.

Large-scale genomic analysis has revealed important molecular distinctions between peritoneal and pleural mesothelioma, including significantly lower frequency of CDKN2A deletions in peritoneal mesothelioma (25.9% vs. 48.2% in pleural) and higher frequency of SETD2 mutations (22% vs. 10.2%). Four molecular subgroups have been identified based on BAP1 and CDKN2A/B alteration patterns, which may have different clinical characteristics and treatment responses.

Key ongoing clinical trials include a phase II trial of perioperative nivolumab + ipilimumab for resectable peritoneal mesothelioma (NCT05041062), trials investigating PIPAC efficacy as both neoadjuvant and palliative modality, and phase I trials of CAR-T cells targeting mesothelin — a protein overexpressed in mesothelioma. Future research priorities include CRS+HIPEC drug optimization, liquid biopsy approaches for monitoring treatment response, and further characterization of the genetic predisposition pathways that underlie the "peritoneal paradox."

⚠ Statute of Limitations Warning: Filing deadlines vary by state from 1-6 years from diagnosis. Texas allows 2 years from diagnosis or discovery. Contact an attorney immediately to preserve your rights.

Related Pages

• Mesothelioma — Overview of all mesothelioma types
• Pleural Mesothelioma — The most common type, affecting the lung lining
• Asbestos Exposure — How asbestos causes disease
• Mesothelioma Quick Facts — Core statistics at a glance
• Statute of Limitations Reference — State-by-state filing deadlines
• Mesothelioma Settlement Quick Reference — Compensation ranges
• Asbestos Trust Fund Quick Reference — Trust fund payouts
• Veterans Mesothelioma Quick Reference — VA benefits guide
• Occupational Exposure Quick Reference — High-risk occupations