Mesothelioma Diagnosis Staging and Prognosis 1 — Questions and Answers
Question 1: Which staging system is most widely used for malignant pleural mesothelioma in the US?
- IMIG/IASLC TNM staging system (Correct answer)
- FIGO staging
- Ann Arbor classification
- Dukes staging
Correct answer: IMIG/IASLC TNM staging system
The IMIG/IASLC TNM-based staging system is the standard for malignant pleural mesothelioma, incorporated into the AJCC Cancer Staging Manual.
Question 2: In the IMIG TNM staging system, Stage I mesothelioma is characterized by:
- Tumor confined to the ipsilateral pleura without nodal involvement (Correct answer)
- Ipsilateral mediastinal lymph node involvement
- Contralateral pleural involvement
- Distant metastases present
Correct answer: Tumor confined to the ipsilateral pleura without nodal involvement
Stage I (IA and IB) mesothelioma is limited to the ipsilateral pleura with no lymph node involvement or distant spread.
Question 3: Which factor is the single most important determinant of survival in mesothelioma?
- Histological cell type (epithelioid vs. sarcomatoid) (Correct answer)
- Age at diagnosis
- Side of involvement (left vs. right)
- Pleural effusion volume
Correct answer: Histological cell type (epithelioid vs. sarcomatoid)
Epithelioid cell type confers significantly better median survival than sarcomatoid or biphasic types, making histology the strongest prognostic variable.
Question 4: Median overall survival for malignant pleural mesothelioma treated with standard chemotherapy is approximately:
- 12–18 months (Correct answer)
- 5 years
- 3–6 months
- 30–36 months
Correct answer: 12–18 months
With first-line cisplatin/pemetrexed chemotherapy, median overall survival is approximately 12 to 18 months from diagnosis.
Question 5: The EORTC prognostic score for mesothelioma assigns worse prognosis to which patient profile?
- Non-epithelioid histology, poor performance status, and high WBC (Correct answer)
- Female gender and early stage
- Low LDH and no weight loss
- Age under 50 with epithelioid type
Correct answer: Non-epithelioid histology, poor performance status, and high WBC
The EORTC score identifies poor-prognosis patients based on non-epithelioid histology, poor ECOG performance status, elevated WBC, and other factors.
Question 6: Extrapleural pneumonectomy (EPP) is a surgical option for which stage of mesothelioma?
- Stage I or II epithelioid mesothelioma in fit patients (Correct answer)
- Stage IV any histology
- Sarcomatoid mesothelioma of any stage
- Any stage with contralateral disease
Correct answer: Stage I or II epithelioid mesothelioma in fit patients
EPP is considered only in highly selected Stage I or II epithelioid mesothelioma patients with good performance status, as it carries high morbidity.
Mesothelioma Diagnosis Staging and Prognosis 1
Which staging system is most widely used for malignant pleural mesothelioma in the US?