Mesothelioma: Diagnosis & Staging

At Memorial Sloan-Kettering, our physicians have extensive expertise in diagnosing mesothelioma. First, a medical history is conducted to determine if the patient has been exposed to asbestos. This is followed by a physical examination, x-rays, lung function tests (for pleural mesothelioma) , and imaging, which may include CT and PET scans to determine the extent of the disease.

Because fluid that is removed from the chest or abdomen of patients with the disease often does not contain cancer cells, a biopsy is necessary to make a diagnosis. The biopsy is performed using video-assisted thoracic surgery, or VATS, while the patient is under general anesthesia. A surgeon places a tiny camera through a small incision in the chest wall so the pleura can be visualized. Instruments to remove tissue are inserted through another small incision. This procedure takes less than an hour, and the patient can usually go home the same day if there are no complications.

A small number of patients with pleural mesothelioma will need to have a minimally invasive procedure known as laparoscopy to determine if the tumor extends into the diaphragm, which is the large muscle that moves up and down to make space for the lungs as we breathe. Laparoscopy is also performed using a tiny video camera placed through a small incision in the abdomen. Instruments are placed through other small incisions, and a biopsy is taken.

For both procedures, the healing and recovery time is short.

Staging

Staging a cancer is a way of describing its location, whether it has spread, and whether it affects other organs. Staging will help determine what type of therapy a patient receives. Mesothelioma is staged using the TNM system (tumor, node, metastasis) plus numbers to describe how advanced it is.

  • stage I and II mesothelioma is confined to the pleura on one lung
  • stage III has invaded the mediastinum (the area between the lungs) or involves lymph nodes
  • stage IV has invaded the chest wall or has spread to other sites in the body