Stage I Mesothelioma

At stage I, tumors remain within the lining of the lung, stomach or heart. You have several treatment options at this stage and are likely to live longer than late-stage patients.

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  • A few tumors or none are visible.
  • Can be treated with therapies like surgery and chemotherapy.
  • Life expectancy upwards of 40 months.

Stage I is the earliest and most treatable stage of mesothelioma. This stage has the best prognosis and longest survival rate.

In this stage, the cancer has just begun to form. Tiny tumors develop along the lining of one lung. The lungs and lymph nodes do not have cancer cells. The cancer has not spread at this point.

Asbestos-related cancer is rarely diagnosed at this stage because symptoms seldom arise that would prompt someone to get medical attention. Stage I cases often are discovered accidentally.

If your symptoms or test results suggest mesothelioma, your doctor will need to take fluid or tissue samples and test them in the lab to confirm the diagnosis. This procedure is called a biopsy, and it's the most accurate method for diagnosing mesothelioma.

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Treatment Options

Because stage I tumors exist only in the lining of the lung, treatments are more effective. A combination of aggressive treatments, known as multimodal therapy, is recommended to people with stage I cancer. Cytoreductive surgery is used to remove the tumors. Chemotherapy is used to kill remaining cancer cells after surgery. Radiation therapy may be used before surgery to shrink tumors, or after surgery to reduce the risk of recurrence.

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Stage I has the best prognosis. Patients who undergo multimodal therapy may live for years beyond the average mesothelioma prognosis. Studies using aggressive multimodal therapy on stage I cases report survival rates around three years. A number of people diagnosed in stage I have lived far beyond three years. Each case of asbestos-related cancer is unique, and the treatments used to manage the cancer are becoming increasingly effective.

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Stage Ia and Ib

Stage I is the only mesothelioma stage that is divided into two categories, Ia and Ib. There are two layers that make up the lining that surrounds the lungs and chest wall. The inner layer that lines the lungs is called the visceral pleura. The outer layer that lines the chest wall is called the parietal pleura. Together they are called the pleural lining.

Tumors most often arise as separate, small nodules across the pleural lining. This scattered pattern of tumor growth is called diffuse mesothelioma.

In imaging scans, indications of stage I cancer include slight thickening of the pleural lining as well as pleural effusion (the accumulation of fluid between the pleural layers). Staging is usually estimated with a CT scan. An MRI may be used to check for local tumor spread, which helps distinguish stage I from other stages. Surgery is the most accurate tool to assess stage, but is also the most invasive.

Stage 1a Stage 1b Diagram

When tumors form on the outer layer closest to the chest wall, a diagnosis of stage Ia is given. When tumors have spread to the inner layer closest to the lung, a diagnosis of stage Ib is given.

Diagnosis of Stage I

If you've been diagnosed with stage I mesothelioma, consider the following:

  • Lifestyle choices and overall health can affect how long you live. Take care of your health, and lead a healthy lifestyle.

  • Survivors often say that adopting an optimistic outlook helped them cope with the diagnosis and treatment process. You may not be able to feel optimistic every day or at every moment, but striving for a positive perspective is a healthy goal to work toward.

  • Emotional support can relieve stress for patients and their caregivers. An online support group for mesothelioma patients and caregivers meets on the second Wednesday of every month. Sign up here

  • You are fortunate. Few people are diagnosed so early. This qualifies you for more aggressive treatment options that could significantly extend survival.

  • Resources are available to people with asbestos-related diseases. Reach out to a patient advocate for more information on available resources.

  • Every case is unique. Statistics on survival cannot predict how long an individual may live or how well they may respond to treatment. People diagnosed at stage I often respond best to aggressive treatment. You have reasons to remain hopeful.

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Symptoms of Stage I

The symptoms of mesothelioma are caused by the tumors developing on the pleural lining and by the buildup of fluid between the pleural layers. The tumors are so small during stage I that they rarely cause symptoms. Pleural effusion may place pressure on the chest wall and lungs, causing chest pain or coughing.

  • Fever
  • Body Aches
  • Chest Pain and Cough

Treatment of Stage I

The treatment options recommended to stage I mesothelioma patients usually have a curative intent, so they are aggressive, but offer the greatest chance of long-term survival. A combination of surgery, chemotherapy and radiation therapy is usually recommended at stage I.

Surgery Icon

Since tumors are localized during stage I, surgical removal is possible. A pleurectomy and decortication surgery removes the lung lining and any visible tumor growth within the chest, and leaves both lungs intact. An extrapleural pneumonectomy surgery goes several steps further by removing one lung, the heart lining, nearby lymph nodes and half of the diaphragm. The recommended surgery will depend on extent of disease spread, overall health of the patient and physician's medical opinion.

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Chemotherapy Icon

Chemotherapy is most often given after a patient recovers from surgery to kill any remaining cancer cells. However, heating chemotherapy and circulating it throughout the pleural space during surgery is a new approach that could become more common if proven effective through further research. The most common chemotherapy drugs for mesothelioma include cisplatin, carboplatin, pemetrexed, doxorubicin and gemcitabine.

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Radiation Therapy Icon

Radiation therapy has traditionally been used after surgery to prevent local recurrence. Recently, researchers started administering radiation therapy before surgery to shrink tumors and prevent tumor seeding (the spread of cancer cells to surgical incisions). This may not be recommended to stage I patients because their tumors are already small. Months or years after surgical procedures, radiation therapy may be used to shrink mesothelioma tumors that return.

In a phase II trial, Dr. Valerie Rusch et al. followed 88 pleural mesothelioma patients of all stages who received surgery and post-surgery radiation therapy. The majority of the patients underwent extrapleural pneumonectomy surgery, but five who were ineligible received a pleurectomy/decortication instead.

The researchers estimated survival for the patients who underwent extrapleural pneumonectomy. Survival was best among stage I and II patients, who experienced a median survival of 33.8 months. Patients with stage III and IV tumors had a median survival of only 10 months.

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Alternative Therapies

Alternative and complementary therapies are often utilized by long-term cancer survivors. Complementary therapies like acupuncture, nutritional therapy, herbal supplementation, yoga and meditation are known to ease side effects caused by the aggressive treatments for stage I mesothelioma.

Prognosis for Stage I

Stage I has the best prognosis of all the stages. A median survival of 40 months is reported when stage I tumors are removed by extrapleural pneumonectomy surgery.

People diagnosed at stage Ia may live around two years without any treatment. Stage Ia and Ib patients who undergo aggressive surgery usually live more than three years.

Mesothelioma is considered a heterogeneous disease, meaning no two cases are alike. Certain patients respond better to treatment and will far surpass the average survival statistics. Some people have lived for two decades with mesothelioma, and several cases of spontaneous remission are documented. New treatment approaches aim to manage the cancer in ways that allow people to live for years beyond the average survival time.

Additional Resources

Karen Selby is a registered nurse and a Patient Advocate at The Mesothelioma Center. She worked in several subspecialties within nursing before joining in 2009.

  1. Cho, B.C.J., Feld, R., Leighl, N., Opitz, I., Anraku, M., Tsao, M., … & de Perrot, M. (2014). A feasibility study evaluating surgery for mesothelioma after radiation therapy: The “SMART” approach for resectable malignant pleural mesothelioma. Journal of Thoracic Oncology, 9(3): 397-402. doi: 10.1097/JTO.0000000000000078
  2. Flores, R.M., & Rusch, V.W. (2005). Staging of mesothelioma. In Pass, H.I., Vogelzang, N.J., & Carbone, M. (Eds.), Malignant Mesothelioma (pp.402-415). New York: Springer.
  3. Rice, D.C. (N/A). Staging of malignant pleural mesothelioma: A guide for patients. Retrieved from
  4. Rusch, V.W., & Giroux, D. (2012). Do we need a revised staging system for malignant pleural mesothelioma? Analysis of the IASLC database. Annals of Cardiothoracic Surgery, 1(4): 438-448. doi: 10.3978/j.issn.2225-319X.2012.11.10
  5. Schil, P.V., Carp, L., Hendriks, J., & Lauwers, P. (2008). Staging of malignant pleural mesothelioma. In Baldi, A. (Ed.), Mesothelioma from Bench Side to Clinic (357-366). New York: Nova Science Publishers, Inc.
  6. Rusch, V. et al. (2001, April 19). A Phase II Trial of Surgical Resection and Adjuvant High-dose Hemithoracic Radiation for Malignant Pleural Mesothelioma. Retrieved from

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