Mesothelioma Prognostic Factors

Mesothelioma prognostic factors are the clinical, pathological, and laboratory variables that predict how long a patient with mesothelioma is likely to survive and which treatments they can safely access. Across multiple peer-reviewed studies, the five most consistently validated prognostic factors are disease stage at diagnosis, histological subtype (epithelioid, biphasic, or sarcomatoid), Eastern Cooperative Oncology Group performance status (ECOG PS), age and sex, and access to multimodal treatment. Modern composite scoring systems — including the EORTC score, the CALGB score, and the newer PLECH score (2025) — integrate these variables into clinically actionable risk strata.

Mesothelioma Prognostic Factors
The Five Variables That Predict Survival
5-Year Relative Survival (All Stages)	~12% (NCI SEER, 2026)
Median Overall Survival (OS), NIVO+IPI	18.1 months
Median OS, Platinum-Pemetrexed	14.1 months
3-Year OS, NIVO+IPI	23%
ECOG PS 0–1 vs PS ≥2 (ICI mOS)	12.6 vs 3.1 months
Non-Epithelioid mOS, NIVO+IPI vs Chemo	16.9 vs 8.8 months
Peritoneal MPM CRS+HIPEC 3-Year SR vs CRS+IP Chemo	65% vs 33%
BAP1 Germline Carrier Median OS	5+ years
Best-Performing Score (2026)	PLECH (Area Under the Curve, or AUC, 0.70)

While prognostic factors do not determine outcomes individually — survival is the result of how they combine with treatment access, supportive care, and time of diagnosis — they remain the framework physicians use to decide treatment intent, trial eligibility, and surgical candidacy. Patients with epithelioid histology, early-stage disease, and Eastern Cooperative Oncology Group performance status (ECOG PS) 0–1 are offered curative-intent multimodal protocols, while patients with sarcomatoid histology, advanced stage, and ECOG PS ≥3 are offered palliative care.

The cost-facts table below reflects current 2026 U.S. averages from public and industry sources and is positioned here so readers can cross-check the page's economic claims against the table on each visit. Costs are billed amounts and vary by insurance, region, and center.

Cost / Compensation Dimension	Typical 2026 Range (USD)	Verified
First-year total billed cost of mesothelioma treatment	$80,000–$160,000	2026-05-25
FDA-approved immunotherapy regimen (nivolumab + ipilimumab, or NIVO+IPI), annual	$180,000+	2026-05-25
Pleurectomy/decortication (P/D) procedural cost	$55,000–$95,000	2026-05-25
Standard cisplatin/pemetrexed chemotherapy course (6 cycles)	$20,000–$50,000	2026-05-25
Average U.S. mesothelioma legal settlement	$1.0M–$1.4M	2026-05-25

Executive Summary

Mesothelioma prognosis is determined not by any single variable but by the interaction of five validated factors. Disease stage captures how far the cancer has spread; histology captures how the tumor cells look and behave; ECOG performance status captures whether the patient is well enough to tolerate aggressive treatment; age and sex modify both biology and treatment access; and treatment center experience modifies whether the patient receives state-of-the-art multimodal care. In 2026, the first-line immunotherapy regimen nivolumab + ipilimumab (NIVO+IPI) — FDA-approved for unresectable malignant pleural mesothelioma (MPM) — extends median overall survival (OS) to 18.1 months from the 14.1 months historically achieved with platinum-pemetrexed chemotherapy, but only for patients with ECOG PS 0 or 1. Patients with ECOG PS ≥2 are largely excluded from these regimens and experience markedly shorter survival — median 3.1 months versus 12.6 months in pooled immune checkpoint inhibitor (ICI) cohorts. Across all stages of pleural mesothelioma, the 5-year relative survival rate is approximately 12%; for peritoneal mesothelioma treated with cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) in eligible patients, peer-reviewed cohort data show a 3-year survival rate of approximately 65%, compared with 33% in CRS-plus-postoperative-intraperitoneal-chemotherapy comparators.

At a Glance

• Five validated prognostic factors drive mesothelioma survival: stage, histology, ECOG performance status, age/sex, and treatment access.
• ECOG PS is the single most universally applied prognostic and treatment-eligibility variable — it gates access to immunotherapy, multimodal surgery, and most clinical trials.
• Epithelioid histology has the best prognosis (~60% of pleural cases; longer overall survival, or OS); sarcomatoid has the worst (~10% of cases; weakest chemotherapy response).
• Non-epithelioid patients derive the largest relative benefit from NIVO+IPI (hazard ratio, or HR, 0.46) because chemotherapy performs especially poorly in sarcomatoid disease.
• ECOG performance status is an independent risk factor for survival in peritoneal mesothelioma on multivariate analysis (p=0.017).
• The PLECH score (2025) — combining platelet count, lactate dehydrogenase (LDH), ECOG PS, chest pain, and histology — outperforms the older EORTC and CALGB scores (AUC 0.70 vs 0.57 and 0.60).
• Female patients consistently show better survival than male patients across mesothelioma cohorts, after adjustment for stage and histology.
• Approximately 90+ active clinical trials are enrolling mesothelioma patients as of early 2026, with most requiring ECOG PS 0–1.

Key Facts

Metric	Value	Source / Notes
5-year relative survival, all stages combined	~12%	NCI Surveillance, Epidemiology, and End Results (SEER), 2026
3-year survival rate, peritoneal mesothelioma (CRS+HIPEC eligible vs CRS+IP chemo comparator)	~65% vs ~33%	PMID 34650746 (44-patient retrospective cohort)
Median OS, NIVO+IPI (CheckMate 743)	18.1 months	U.S. Food and Drug Administration (FDA) BLA review; PMID 34462287
Median OS, platinum-pemetrexed (CheckMate 743)	14.1 months	FDA BLA review; PMID 34462287
Hazard ratio for OS, NIVO+IPI vs chemotherapy	0.74 (95% CI, 0.61–0.89; p=0.002)	CheckMate 743
3-year OS rate, NIVO+IPI vs chemotherapy	23% vs 15%	CheckMate 743 3-year update
Non-epithelioid mOS, NIVO+IPI vs chemotherapy	16.9 vs 8.8 months (HR 0.46; 95% CI 0.31–0.70)	CheckMate 743
Epithelioid mOS, NIVO+IPI vs chemotherapy	18.7 vs 16.2 months (HR 0.85; 95% CI 0.68–1.06)	CheckMate 743
ECOG PS as independent prognostic factor in peritoneal mesothelioma (multivariate analysis)	Confirmed (p=0.017)	PMID 34650746
Median OS, ICI patients with ECOG PS 0–1 (all advanced solid tumors)	12.6 months	JCO Oncology Practice 2022
Median OS, ICI patients with ECOG PS ≥2 (all advanced solid tumors)	3.1 months	JCO Oncology Practice 2022
PLECH score area under the curve (AUC) for 1-year OS prediction	0.70	PLECH Karger Oncology, 2025
CALGB score AUC for 1-year OS prediction	0.60	PLECH Karger Oncology, 2025
EORTC score AUC for 1-year OS prediction	0.57	PLECH Karger Oncology, 2025
Average annual U.S. mesothelioma incidence	~3,000 cases	NCI / American Cancer Society
Active recruiting mesothelioma clinical trials (early 2026)	~90–93	ClinicalTrials.gov

What Are the Most Important Prognostic Factors in Mesothelioma?

Multiple peer-reviewed studies, including the comprehensive Danish clinical guidelines published in 2025, identify five core prognostic factors that together predict survival and gate treatment access. The factors are described in detail below.

Factor 1: Disease Stage

Disease stage at diagnosis remains a fundamental survival predictor. The American Joint Committee on Cancer (AJCC) 8th Edition Tumor, Node, Metastasis (TNM) staging system is the current standard for pleural mesothelioma. In the pivotal CheckMate 743 trial, 87% of patients in the immunotherapy arm presented with Stage III or Stage IV disease — reflecting how typical the late-stage presentation of malignant pleural mesothelioma (MPM) is at diagnosis. In peritoneal mesothelioma specifically, TNM stage was confirmed as an independent risk factor for prognosis in multivariate Cox regression analysis (OR 2.142; p=0.038), alongside ECOG score and treatment modality.

Population-level data from the NCI Surveillance, Epidemiology, and End Results (SEER) program show that the 5-year relative survival rate across all stages combined is approximately 12% — an improvement from the 5–8% seen in the early 2000s, but still representing a disease with a very poor prognosis. In contrast, peritoneal mesothelioma treated with cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) in eligible patients achieves substantially better near-term survival than CRS-alone comparators — peer-reviewed cohort data report a 3-year survival rate of approximately 65% in the CRS+HIPEC subgroup versus 33% in CRS plus postoperative intraperitoneal chemotherapy. This difference reflects both disease biology (peritoneal disease tends to remain locally aggressive rather than metastasizing widely) and the intensity of the surgical approach.

The clinical implication is that stage informs treatment intent. Stage I and Stage II patients with epithelioid histology and ECOG PS 0–1 may be candidates for curative-intent multimodal surgery; Stage III patients are candidates for chemoimmunotherapy with selective surgery; Stage IV patients are typically managed with systemic therapy and palliative care.

Factor 2: Histological Subtype

Histological subtype is one of the strongest prognostic determinants in malignant pleural mesothelioma. The three principal subtypes are epithelioid, sarcomatoid, and biphasic.

• Epithelioid mesothelioma is the most common subtype, accounting for approximately 60% of pleural cases (76% in the CheckMate 743 cohort). It carries the best prognosis, the most reliable response to chemotherapy, and the longest overall survival across treatment regimens.
• Sarcomatoid mesothelioma accounts for approximately 10% of cases and carries the worst prognosis, with the poorest response to chemotherapy. However, sarcomatoid tumors often express higher levels of programmed death-ligand 1 (PD-L1), which may make them more responsive to immunotherapy than to chemotherapy alone.
• Biphasic mesothelioma accounts for approximately 25–30% of cases and shows an intermediate prognosis. The outcome worsens as the sarcomatoid component increases. Many surgical multimodal protocols restrict candidacy to biphasic tumors with less than 50% sarcomatoid component.

The clinical impact of histology is most clearly illustrated in CheckMate 743 subgroup data, where non-epithelioid patients derived a substantially greater relative benefit from nivolumab + ipilimumab (NIVO+IPI) compared with chemotherapy than epithelioid patients did. The non-epithelioid hazard ratio (HR) for overall survival was 0.46 (95% CI, 0.31–0.70), compared with 0.85 (95% CI, 0.68–1.06) for the epithelioid subgroup. The reason is largely that chemotherapy performs especially poorly in sarcomatoid disease, leaving more headroom for immunotherapy to outperform it.

According to multiple sources, female sex distribution differs by subtype and primary site: biphasic and sarcomatoid pleural mesothelioma show stronger male predominance, while peritoneal mesothelioma — disproportionately epithelioid — shows a near-equal male-to-female ratio.

Factor 3: ECOG Performance Status

Eastern Cooperative Oncology Group performance status (ECOG PS) is a clinician-assessed score measuring a cancer patient's ability to perform everyday activities. It is the most universally applied performance-status measure in oncology and is used for:

• Determining eligibility for chemotherapy, immunotherapy, and clinical trials
• Guiding dose-intensity decisions
• Estimating prognosis

The ECOG scale and its treatment implications are summarized below.

Score	Definition	Clinical Interpretation	Treatment Implications
0	Fully active; no restrictions	Excellent performance status; able to perform all pre-disease activities	Eligible for all treatment modalities including aggressive multi-agent chemotherapy, major surgery, immunotherapy, and all Phase III trials
1	Restricted in strenuous physical activity but ambulatory; able to do light work	Mild symptoms, still functional	Eligible for essentially all standard systemic therapies and most clinical trials
2	Ambulatory and capable of self-care; unable to work; up and about more than 50% of waking hours	Moderate symptoms; intermediate group	Increasingly included in trials; requires heightened toxicity monitoring; some mesothelioma-specific trials exclude this group
3	Capable of only limited self-care; confined to bed or chair more than 50% of waking hours	Poor prognosis; limited functional reserve	Palliative care focus; systemic chemotherapy generally contraindicated; aggressive treatment delays end-of-life care without benefit
4	Completely disabled; cannot carry on any self-care; totally confined to bed	Very poor prognosis	Systemic therapy rarely appropriate; exclusively palliative and supportive care
5	Deceased	—	—

In mesothelioma specifically, the pivotal CheckMate 743 trial — which established nivolumab + ipilimumab as the first new FDA-approved first-line regimen in over 15 years — restricted enrollment to patients with ECOG PS 0 or 1. Of the immunotherapy arm, 38% had ECOG PS 0 and 62% had ECOG PS 1; ECOG PS ≥2 patients were almost entirely excluded.

The survival impact of ECOG performance status outside the trial population is substantial. A retrospective analysis of 257 patients with advanced solid tumors treated with immune checkpoint inhibitors (ICIs) found a median overall survival of 12.6 months for ECOG PS 0–1 versus 3.1 months for ECOG PS ≥2 (p<0.001). The overall response rate was 23% for PS 0–1 versus 8% for poor PS (p=0.005).

In peritoneal mesothelioma, ECOG performance status is an independent prognostic factor confirmed in multivariate Cox regression. A retrospective analysis of 44 peritoneal mesothelioma patients treated with cytoreductive surgery (CRS) found that the cytoreductive-surgery-plus-HIPEC subgroup achieved a 3-year survival rate of 65.22% versus 33.33% for the cytoreductive-surgery-plus-postoperative-intraperitoneal-chemotherapy comparator. On multivariate analysis, ECOG score was independently associated with prognosis (p=0.017), alongside TNM stage and treatment modality.

Patients with ECOG PS ≥3 should generally not receive systemic chemotherapy because the toxicity profile delays end-of-life care without demonstrable survival benefit. This is a clinical consensus across the Danish clinical guidelines and prior treatment-eligibility frameworks.

Factor 4: Age and Sex

Age and sex are both prognostic modifiers in mesothelioma, though they operate differently from the other factors. Mean age at diagnosis exceeds 70 years in most Western countries because of mesothelioma's long latency (approximately 40 years between asbestos exposure and disease onset). Older age is associated with worse outcomes in part because of comorbidity burden and in part because surgical multimodal protocols are restricted to patients under approximately 75 years.

According to multiple registry and case-series analyses, female patients show better overall survival than male patients across mesothelioma cohorts, after adjustment for stage and histology. The male-to-female ratio for pleural mesothelioma is approximately 3.5–4:1 in most U.S. series, reflecting historical occupational exposure patterns; for peritoneal mesothelioma, the male-to-female ratio is closer to 1.2:1. Several registry analyses describe meaningfully better survival in women than in men with mesothelioma; the underlying mechanism is debated and may involve hormonal modulation, immune-response differences, or differences in exposure intensity rather than a single causal pathway.

For women in particular, mesothelioma is increasingly attributed to environmental, para-occupational (take-home), or unknown exposure pathways rather than direct workplace exposure. This shifts both the clinical profile (younger age at diagnosis is more common in para-occupational cases) and the legal profile (different defendants, different proof requirements) of female mesothelioma cases. See Secondary_Asbestos_Exposure for the detailed exposure-pathway analysis.

Germline mutations in BAP1 (BRCA-Associated Protein 1) are a special case: BAP1 carriers tend to present younger, often with multifocal low-grade tumors, and carry a median overall survival exceeding 5 years — substantially longer than non-carriers.

Factor 5: Treatment Access and Volume

Whether a patient with mesothelioma is treated at a high-volume academic center with multidisciplinary expertise is itself a prognostic factor. The Danish clinical guidelines and multiple registry analyses describe surgery within multimodal protocols as restricted to patients treated at centers with thoracic surgical expertise and pathology infrastructure capable of biphasic-component grading, which is itself a function of center volume. Across registry comparisons, peritoneal mesothelioma patients tend to be diagnosed younger (median ~62 years vs ~73 years for pleural), are more often treated at academic centers, and more often undergo surgery (CRS+HIPEC), which together explain a meaningful share of the median-OS gap between peritoneal and pleural disease.

Treatment access has direct implications for the choice of first-line regimen, surgical candidacy, and clinical trial enrollment. Where insurance coverage, trust-fund eligibility, and Veterans Affairs benefits intersect with the prognostic timeline, the financial planning has to track the medical plan rather than compete with it. See the Compensation section below for the legal-resource pathways patients commonly pursue.

What Molecular Biomarkers Affect Mesothelioma Prognosis?

Beyond the five clinical prognostic factors above, several molecular markers influence prognosis. These are not used as standalone prognostic tools but are integrated into pathology reports and trial-enrollment decisions.

• BAP1 (BRCA-Associated Protein 1) loss — immunohistochemistry (IHC)-detected loss of nuclear BAP1 expression is associated with a more favorable prognosis, particularly in younger patients with germline BAP1 mutations. Germline BAP1 mutations are found in approximately 7–12% of patients with pleural mesothelioma; carriers tend to develop the disease at younger ages and survive longer than non-carriers.
• CDKN2A (Cyclin-Dependent Kinase Inhibitor 2A) deletion — homozygous deletion of CDKN2A, detected by fluorescence in situ hybridization (FISH), or its surrogate methylthioadenosine phosphorylase (MTAP) loss, detected by IHC, correlates with shorter overall survival. CDKN2A deletion is found in 40–70% of epithelioid and biphasic pleural mesothelioma and approximately 90% of sarcomatoid disease.
• Programmed death-ligand 1 (PD-L1) expression — higher PD-L1 expression correlates with worse survival in chemotherapy-treated patients but may predict immunotherapy benefit. Exploratory subgroup analyses in CheckMate 743 suggested a larger OS benefit from NIVO+IPI in PD-L1 ≥1% tumors.
• NF2 / Merlin loss — deletions or mutations of the NF2 gene are common in pleural mesothelioma but are not currently used as routine prognostic biomarkers because of late and heterogeneous occurrence.

Several clinical and laboratory variables described in the Danish clinical guidelines are also recognized as prognostic in mesothelioma: chest pain at diagnosis, weight loss, dyspnea, anemia, leukocytosis, thrombocytosis, elevated lactate dehydrogenase (LDH), and elevated platelet count.

Which Prognostic Scoring Systems Are Used in Mesothelioma?

Several composite prognostic scoring systems integrate the individual variables above into clinically actionable risk strata. Their performance has been compared head-to-head in retrospective cohorts. The 2025 PLECH score is the newest and best-performing system in published comparisons.

Score	Key Variables	AUC for 1-Year OS	ECOG Included?	Status
EORTC	Performance status (PS), histology, white blood cell (WBC) count, sex, type of diagnosis	~0.57	Yes (PS)	Historical; recent cohorts show inconsistent prediction
CALGB	Age, PS, lactate dehydrogenase (LDH), WBC, hemoglobin (Hgb), histology	~0.60	Yes (PS)	Historical; the most widely referenced score for predicting chemotherapy benefit
Brims	Decision tree across multiple clinical variables	Significant OS prediction (p<0.01)	Yes	UK-derived; better performance in head-to-head comparisons with EORTC and CALGB
modified Glasgow Prognostic Score (mGPS)	C-reactive protein (CRP) and albumin	Significant OS prediction (p=0.01)	No	Inflammation-based; simple lab-only score
LENT	LDH, ECOG PS, neutrophil-to-lymphocyte ratio (NLR), tumor type	Inconsistent validation across cohorts	Yes	Originally validated in malignant pleural effusion, not exclusively mesothelioma
PLECH (2025)	Platelets, LDH, ECOG ≥2, chest pain, histology	0.70	Yes	Newest; derived from 262 patients at two Mexican centers; outperforms EORTC and CALGB

The PLECH score is a 0–7 point system in which elevated platelet count contributes +2 points, elevated LDH +1, ECOG ≥2 +1, chest pain at diagnosis +2, and non-epithelioid histology +1. A high score (≥3) was associated with worse overall survival (12.3 vs 20.1 months; p<0.001) and worse progression-free survival (6.4 vs 11.3 months; p<0.001) in the derivation cohort.

Compensation, Trust Funds, and the Prognostic Timeline

The prognostic profile a patient receives at diagnosis directly shapes how compensation planning unfolds. A patient with ECOG PS 0–1 and epithelioid Stage I–II disease has the longest planning horizon: years of treatment decisions, trial considerations, and financial planning. A patient with ECOG PS 2–3 and non-epithelioid Stage IV disease has a substantially compressed horizon — often months — and the legal and financial timeline has to match.

Asbestos trust funds — established under Section 524(g) of the U.S. Bankruptcy Code — currently hold an aggregate of approximately $30 billion to compensate mesothelioma patients exposed to defendants who have since filed for bankruptcy. The timing of trust-fund filings against the prognostic timeline is one of the most consequential decisions a patient and family make in the first 30 days after diagnosis.

Settlements and Verdicts

Average mesothelioma legal settlements range from $1.0 million to $1.4 million, with average jury verdicts in the $5 million to $11.4 million range. Plaintiff law firms with experience in compressed-timeline mesothelioma cases structure compensation pathways to align trust-fund filings, settlement negotiations, and active treatment so that financial planning supports rather than competes with the medical plan. See External Links for resources.

Treatment Access by Prognostic Profile

The treatment options realistically available to a mesothelioma patient are a function of the prognostic profile they present with. The table below summarizes typical treatment access by ECOG score, the single variable most commonly used to determine eligibility.

ECOG Score	Treatment Options Realistically Available	Evidence
0	Full multimodal: lung-preserving surgery (pleurectomy/decortication or P/D), immunotherapy (NIVO+IPI), platinum-pemetrexed chemotherapy, clinical trials, cytoreductive surgery (CRS) + HIPEC for peritoneal disease	Best outcomes; 3-year OS up to 23% with NIVO+IPI; eligible for all modalities
1	Full multimodal (same as ECOG 0)	Eligible for standard and experimental protocols; 62% of CheckMate 743 NIVO+IPI arm
2	Limited systemic therapy (carboplatin+pemetrexed often preferred over cisplatin); selected trials; immunotherapy with heightened caution	Median OS ~3.1 months in pooled ICI cohorts vs 12.6 months for PS 0–1; largely excluded from mesothelioma-specific pivotal trials
3	Palliative: best supportive care, symptom management, pleurodesis or indwelling pleural catheter (IPC) for effusion, palliative radiotherapy (RT)	Systemic chemotherapy generally contraindicated; delays end-of-life care without survival benefit
4	Exclusively palliative and supportive care	Systemic therapy rarely if ever appropriate

Approximately 90 to 93 mesothelioma clinical trials are actively recruiting as of early 2026. Most require ECOG PS 0–1 enrollment; a smaller number extend to ECOG PS 2 in specific protocols.

Related WikiMesothelioma Resources

Patients and families researching mesothelioma prognosis often need to cross-reference related medical and legal topics. Helpful WikiMesothelioma pages include:

• Mesothelioma_Prognosis — broader prognostic context including survival statistics, life-expectancy ranges, and treatment-era comparisons
• Pleural_Mesothelioma — the most common mesothelioma type (~80–85% of cases), with detailed clinical and pathological coverage
• Peritoneal_Mesothelioma — abdominal mesothelioma, including CRS+HIPEC outcomes that drive the favorable 5-year survival in eligible patients
• Mesothelioma_Staging — AJCC 8th Edition TNM staging system in detail
• Mesothelioma_Treatment — first-line and second-line treatment regimens, including the NIVO+IPI immunotherapy backbone
• Asbestos_Trust_Funds — Section 524(g) trust-fund overview and filing pathways
• Mesothelioma_Specialists — high-volume mesothelioma treatment centers

Frequently Asked Questions

What are the five most important prognostic factors in mesothelioma?

The five validated prognostic factors are: disease stage at diagnosis (AJCC 8th Edition TNM), histological subtype (epithelioid, biphasic, or sarcomatoid), ECOG performance status (0–4 scale), age and sex (older age and male sex correlate with worse outcomes), and treatment access (high-volume academic centers produce substantially better 5-year survival). ECOG performance status is the single most universally applied because it gates eligibility for immunotherapy, surgery, and most clinical trials.

How does ECOG performance status affect mesothelioma survival?

ECOG performance status has both direct and indirect effects on survival. Directly, in pooled cohorts of patients treated with immune checkpoint inhibitors, ECOG PS 0–1 patients had a median overall survival of 12.6 months versus 3.1 months for ECOG PS ≥2. Indirectly, ECOG PS gates access to the most effective therapies — the FDA-approved NIVO+IPI regimen, multimodal surgery, and most Phase III trials all require ECOG PS 0–1. Patients with ECOG PS ≥3 are typically managed with palliative care because systemic chemotherapy delays end-of-life care without demonstrable survival benefit.

Which histological subtype of mesothelioma has the best prognosis?

Epithelioid mesothelioma has the best prognosis. It accounts for approximately 60% of pleural mesothelioma cases and shows the most reliable chemotherapy response and the longest overall survival. Sarcomatoid mesothelioma — approximately 10% of cases — has the worst prognosis. Biphasic mesothelioma — approximately 25–30% of cases — has an intermediate prognosis that worsens as the sarcomatoid component increases.

What is the median survival for mesothelioma with the FDA-approved immunotherapy?

In the CheckMate 743 trial, patients with unresectable malignant pleural mesothelioma treated with first-line nivolumab + ipilimumab (NIVO+IPI) had a median overall survival of 18.1 months, compared with 14.1 months for patients treated with platinum-pemetrexed chemotherapy. The hazard ratio for overall survival was 0.74 (95% CI, 0.61–0.89; p=0.002). At 3-year follow-up, the OS rate was 23% in the NIVO+IPI arm versus 15% in the chemotherapy arm. ECOG PS 0–1 was a strict enrollment requirement.

Why do peritoneal mesothelioma patients have better 5-year survival than pleural patients?

The near-term survival difference between peritoneal and pleural mesothelioma reflects three factors. First, peritoneal mesothelioma is more often locally aggressive and less often metastatic at diagnosis, making cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) viable for a higher proportion of patients. Second, peritoneal patients tend to be diagnosed younger (median ~62 years vs ~73 years for pleural). Third, peritoneal patients are more often treated at high-volume academic centers and more often receive surgery. In CRS+HIPEC-eligible peritoneal patients, peer-reviewed cohort data report a 3-year survival rate of approximately 65%, compared with 33% in CRS-plus-postoperative-intraperitoneal-chemotherapy comparators.

What is the PLECH score, and how does it compare to CALGB and EORTC?

The PLECH score is a 0–7 point composite prognostic score derived in 2025 from 262 patients at two Mexican cancer centers. It integrates five variables: elevated Platelet count (+2 points), elevated LDH (+1), ECOG ≥2 (+1), Chest pain at diagnosis (+2), and non-epithelioid Histology (+1). A high score (≥3) was associated with worse overall survival (12.3 vs 20.1 months; p<0.001). In head-to-head comparison, PLECH had an area under the curve (AUC) of 0.70 for 1-year overall survival prediction, outperforming both CALGB (0.60) and EORTC (0.57).

External Links

• Danziger & De Llano
• NCI SEER — Mesothelioma Cancer Stat Facts
• ClinicalTrials.gov — Mesothelioma trial search
• National Cancer Institute — Mesothelioma