Dr. James Stevenson, Cleveland Clinic, sits down for a conversation with Mary Hesdorffer, executive director of the Mesothelioma Applied Research Foundation and expert mesothelioma nurse practitioner, about staging of mesothelioma. They address the question of whether staging matters and can it predict outcomes?
Recently, advancements have been made in the field of mesothelioma treatment, including immunotherapy and BAP1. While those successes have taken the spotlight and encouraged doctors and patients working to learn more about meso, there is still a way to go in understanding this cancer. One area where doctors are working to make improvement is staging. Staging helps doctors know how much cancer is within the patient’s body and if it has spread.
Screening
There hasn’t been a useful way for doctors to screen for mesothelioma. Chest x-rays may help screen other types of cancer, but there is no evidence that the procedure can show mesothelioma at an early stage or help determine prognosis. Early stage lung cancer can be seen in some x-rays and in that process the occasional advanced mesothelioma is seen as well. Because of the nature of mesothelioma in terms of the delay from exposure to development of the disease, there is a lack of a precise test that has proved useful to screen. At one time, blood markers were thought of possibly being a way to screen for mesothelioma, but doctors found it was hard to find the appropriate patient to screen and the length of the process was grueling for some patients.
Staging
The stage of a cancer conveys to the patient and physician if the cancer has spread and if it’s metastasized to the lymphatic system or other organs, etc. This information is used to determine the course of treatment (i.e. whether the cancer is operable or not), as well as prognosis (predicting a patient’s survival time). For scientists, this classification is also helpful in a research setting as it allows comparison of patients (simplistically, it allows them to compare apples to apples.)
TNM is the staging system generally used in pleural mesothelioma (no staging exists for peritoneal). This is based on three pieces of information, which can be even further broken down:
T: the extent of spread of the main tumor.
N: the spread of cancer to nearby (regional) lymph nodes.
M: indicates whether the cancer has spread (metastasized) to other organs of the body.
Mesothelioma, as a whole, is more difficult to stage than other cancers, because to accurately gain information that will help stage, the patient may need to undergo surgery. In terms of staging, this may help doctors learn more about the cancer and whether it is epithelioid, biphasic, or sarcomatoid. Doctors will use this information to consult with patients and their family to decide whether surgery should be part of their treatment plan. Mesothelioma is harder to measure and stage compared to other tumors, because with mesothelioma the tumor grows like a sheet over different areas of the body.
Treatment decisions
Even though there is not a routine practice to staging every type of mesothelioma that doesn’t mean doctors can’t prescribe appropriate treatment. Meso patients should go to an expert academic center where doctors will rely on an expert team of physicians, surgeons and researchers to help determine the path forward. Doctors will also rely on patients to be as open as possible in describing symptoms. Histology is one of the initial points for doctors to determine how aggressive they need to be with treatment. The mediastinum is an area of the chest where major organs and major blood vessels come together. Body parts such as the heart, trachea, lymph nodes and glands are areas doctors need to examine to help prescribe the best treatment for each patient. Knowing if there is lymph node involvement helps decide if surgery is needed. Surgery is more appropriate if lymph nodes are involved, but wouldn’t be appropriate for a patient whose meso is further away from the mediastinum in the chest. Less than 15% of patients with mesothelioma are considered operable. If they are, surgery is considered a life prolonging procedure, not a curative procedure like lung, colon or breast cancer surgery. According to Dr. Stevenson, the Checkmate 74 clinical trial found that immunotherapy works best in patients with sarcomatoid and biphasic cancer. Epithelioid patients responded better to chemotherapy as a first line treatment.
Our sponsors
MesoTV is a program by the Mesothelioma Applied Research Foundation. This program is made possible by our generous sponsors: Maune Raichle Hartley French & Mudd, LLC (MRHFM); Belluck & Fox; Bristol Myers Squibb; Novocure; Merck; The Gori Law Firm; Early Lucarelli Sweeney & Meisenkothen.
