Surgery and Staging of Malignant Mesothelioma

Understanding the Role of Surgery in Mesothelioma Treatment

Malignant mesothelioma is one of the most challenging cancers to treat, and for many years, surgery was considered to have limited value beyond diagnosis and symptom relief. However, in recent years, advances in surgical techniques, combined with chemotherapy and radiation, have changed the landscape of mesothelioma treatment.

Surgery for mesothelioma generally falls into three main categories:

1. Diagnostic Surgery – Procedures to obtain biopsies and confirm mesothelioma.
2. Palliative Surgery – Aimed at relieving symptoms like fluid buildup and pain.
3. Potentially Curative Surgery – Aggressive procedures designed to remove as much tumor as possible, often combined with other therapies.

Let’s dive into the current staging systems and surgical approaches to see how mesothelioma can be better managed today.

Staging of Mesothelioma: Where Are We Now?

Staging is essential in mesothelioma because it determines treatment options and gives a prognostic outlook. Unlike other cancers, mesothelioma grows differently, often spreading along the pleural lining instead of forming a single, well-defined tumor.

Current Staging Systems

Mesothelioma staging has evolved over time, with the TNM (Tumor, Node, Metastasis) system being the most commonly used today.

TNM Staging System for Pleural Mesothelioma

For peritoneal mesothelioma, staging is less standardized, but it generally follows a similar localized-to-widespread pattern.

Key Takeaway: Staging is crucial because early-stage patients may be candidates for aggressive surgery, while late-stage patients typically receive palliative care.

Surgical Approaches in Mesothelioma

Surgery can play a major role in mesothelioma treatment, especially in earlier stages where tumor removal is possible.

1. Diagnostic Surgery: Getting a Clear Answer

Before any treatment begins, a definitive diagnosis is required. This is done through:

• Thoracoscopy (Pleural Mesothelioma) – A minimally invasive procedure where a small camera is inserted into the chest to collect biopsy samples.
• Laparoscopy (Peritoneal Mesothelioma) – Similar to thoracoscopy, but performed in the abdomen.
• Mediastinoscopy – Used to check for lymph node involvement.
• Fine Needle Aspiration (FNA) Biopsy – A less invasive method, but less accurate than surgical biopsies.

Key Takeaway: The most accurate way to diagnose mesothelioma is through surgical biopsy, as needle biopsies may miss tumor cells.

2. Palliative Surgery: Easing Symptoms

For patients not eligible for aggressive surgery, palliative procedures can significantly improve quality of life.

• Pleurodesis – A procedure to prevent fluid buildup in the pleura by sealing the space with substances like talc.
• Thoracentesis/Paracentesis – Draining excess fluid from the chest or abdomen to relieve breathing difficulties.
• Pleurectomy without Decortication (PWD) – Removal of the pleural lining to reduce symptoms, but not intended for cure.

Key Takeaway: Palliative surgeries don’t remove the cancer, but they help control symptoms and improve comfort.

3. Potentially Curative Surgery: Aiming for Maximum Tumor Removal

For select patients, aggressive surgery combined with chemotherapy and radiation can extend survival.

Extrapleural Pneumonectomy (EPP)

The most radical surgery, EPP involves:

• Removing the entire affected lung.
• Excising the pleura, pericardium (heart lining), and diaphragm.
• Reconstructing the diaphragm and pericardium with synthetic material.

Who is eligible?

• Patients with early-stage mesothelioma (Stage 1-2).
• Good overall health and strong lung function.
• No distant metastases.

Key Takeaway: EPP is extremely aggressive, but some studies show it can extend survival when combined with chemotherapy and radiation.

Pleurectomy/Decortication (P/D)

A less aggressive alternative to EPP that spares the lung while removing:

• The pleural lining.
• Any visible tumor growth.
• Portions of the diaphragm or pericardium (if needed).

Who is eligible?

• Patients with epithelioid mesothelioma (better prognosis).
• Those who cannot tolerate full lung removal.

Key Takeaway: P/D has fewer complications than EPP, but it may not remove all cancer cells.

Emerging Surgical Techniques and Combined Therapies

In addition to surgery, newer therapies are being used to boost survival rates.

1. Heated Intraperitoneal Chemotherapy (HIPEC)

• Used in peritoneal mesothelioma.
• After tumor removal, heated chemotherapy is circulated in the abdomen to kill remaining cancer cells.
• Can extend survival to 5+ years in some cases.

2. Intraoperative Photodynamic Therapy (PDT)

• Light-sensitive drugs are used to target residual cancer cells during surgery.
• Helps reduce recurrence rates.

3. Immunotherapy and Surgery

• Checkpoint inhibitors (nivolumab, pembrolizumab) are being studied in combination with surgery.
• May boost the immune system’s ability to fight residual tumor cells.

Key Takeaway: Multimodal therapy (surgery + chemo + radiation + immunotherapy) offers the best hope for survival in early-stage mesothelioma.

Which Surgery is Right for You?

Choosing the right surgical approach depends on:

1. Stage of Mesothelioma – Early-stage patients may qualify for aggressive surgery, while late-stage patients benefit more from palliative procedures.
2. Cell Type – Epithelioid mesothelioma responds better to surgery than sarcomatoid mesothelioma.
3. Overall Health – Younger, healthier patients are better candidates for aggressive surgery.
4. Lung Function – Patients with strong lung function may tolerate EPP, while weaker patients may be better suited for P/D.

Final Thoughts

• Surgery is playing an increasing role in mesothelioma treatment, especially when combined with chemotherapy and radiation.
• Early-stage patients benefit most from aggressive procedures like EPP or P/D, while later-stage patients focus on symptom relief.
• Advancements like HIPEC, PDT, and immunotherapy are improving survival rates.
• Staging is essential for determining the best treatment plan.

Key Takeaway: While surgery alone may not cure mesothelioma, a multimodal approach that includes chemotherapy, radiation, and immunotherapy provides the best chance for extended survival.