Mesothelioma is not an easy disease to diagnose. Often a number of investigations and hospital visits are required and even then it is not always possible to be certain that mesothelioma is present.
Symptoms & Referral
The earliest signs of the disease can be quite vague. The most common symptoms are breathlessness, chest pain, fatigue and weight loss.
In most cases the first sign of something being wrong is when breathlessness or pain in the chest occur as a result of an effusion. This is when fluid accumulates in the space (pleural cavity) between the two layers of the pleural lining. At this stage the patient will often visit their GP.
Once a diagnosis of mesothelioma has been made, it is helpful for the doctor to determine the stage of the disease. The stage describes the size and position of the cancer and whether or not there is evidence that it has spread to nearby tissues or to other, more distant, sites. Staging can be helpful in assessing prognosis, in making recommendations for treatment and in assessing and comparing the results of treatment. However, staging mesothelioma is dirfficult, the tumour is rarely present in a measurable manner.
Different systems have been established for staging mesothelioma. Here is a shortened version of the International Mesothelioma Interest Group (IMIG) staging system:-
STAGE 1 Disease limited to the pleura only on one side of the chest.
STAGE 2 Disease limited to the pleura on one side of the chest but the cancer cells have extended from the pleura into the underlying lung tissue or muscle of the diaphragm.
STAGE 3 The cancer has either spread beyond the pleura to glands in the chest and/or has advanced deeper into the tissues surrounding the pleura.
STAGE 4 The cancer has spread to distant organs or tissues or invaded deeply into tissues close to the pleura e.g. across the diaphragm into the abdomen, into the pleura of the opposite lung or into the spine or heart muscle.
In order to stage the extent of disease a CT scan is usually carried out and may be all that is required. Other scans that are occasionally used in some centres include Magnetic Resonance Imaging (MRI), Ultrasound Scan (USS) and Positron Emission Tomography (PET) scans.
To assist in the diagnosis and treatment of cancer, hospitals have teams of doctors and nurses, each with their own areas of expertise, who work together to try and provide the best care for patients.
These are known as Multi-Disciplinary Teams (MDTs). These teams are made up of Consultant doctors, radiologists, pathologists, oncologists (doctors who treat cancers using chemotherapy and radiotherapy), surgeons and specialist nurses. These teams meet regularly to discuss the cases of individual patients, with confirmed or suspected mesothelioma, to agree on the likelihood of the diagnosis being correct, on the stage of the disease and best treatment strategy. The wishes of the patient are taken into close consideration when treatment plans are discussed. Following MDT discussion treatment options will be explained to the patient and referrals will be made as necessary.
Some centres in the UK now have specialist mesothelioma MDT's where complex cases can be discussed, although for most patients, discussion will be held in a lung cancer (pleural mesothelioma) or gastro-intestinal (peritoneal mesothelioma) MDT.