Chemotherapy

Chemotherapy means the use of chemicals to treat mesothelioma. Cancer cells grow, divide and increase in number very fast. Chemotherapy aims to kill the cancer cells to stop them reproducing. Chemotherapy also kills healthy cells. This gives rise to its side effects.

Chemotherapy can be given before surgery, to shrink the tumour. It can be given after surgery to try to kill any cancer cells left behind. This is called adjuvant therapy. Chemotherapy is often given as an alternative to surgery, where surgery will not help.

Chemotherapy will often shrink the mesothelioma or slow its growth. It is not likely to cure mesothelioma. It is difficult or impossible for doctors to predict in advance how much good it will do.

Chemotherapy is given at hospital. It takes several hours each time. The chemicals are usually put into a vein using a catheter or needle. You will usually be given several treatments.

Chemotherapy may be the main or only treatment to try to prevent the mesothelioma from spreading.

It may be used to shrink the tumour, or as a way of relieving pain.
Many doctors now think that it is good practice to offer palliative chemotherapy, which is chemotherapy that may help symptoms, to mesothelioma patients.

A common combination of chemotherapy for mesothelioma is a drug called Alimta (or Pemetrexed), given with another drug called Cisplatin. This combination has been shown to shrink mesotheliomas and prolong the lives of patients to some extent, compared with the use of Cisplatin alone (see below). Alimta is sometimes given with Carboplatin.

After a long campaign by doctors, politicians, Unions, Asbestos Support Groups and committed individuals, Alimta was in June 2007 approved by the National Institute of Health and Clinical Excellence (NICE) in England and Wales for first line treatment of mesothelioma. It is now widely available on the NHS. However, in some areas, its use is still restricted.

The commonest side effects are nausea, tiredness and a sore mouth or mouth ulcers. Many patients tolerate the treatment well.

The United Kingdom Mesothelioma Trial (MSO1), supported by the British Thoracic Society, the Medical Research Council and Cancer Research UK, reported in May 2008.

This compared the effectiveness of two different types of chemotherapy treatment as against active supportive care without chemotherapy.

The Trial identified no significant survival benefit from the addition of chemotherapy to active supportive care, and no evidence of a difference in quality of life, when the two chemotherapy regimes were analyzed together. However, exploratory analyses suggest that one of the regimes, Vinorelbine, may provide benefit, and needs further investigation.

It was not possible to include patients treated with Alimta (Pemetrexed) in the Trial, so this trial says nothing about Alimta.

In an earlier trial, 456 patients were randomly assigned to receive Cisplatin alone or Cisplatin plus Pemetrexed (Alimta). The combination group had a median survival of 12·1 months compared with 9·3 months for patients in the cisplatin-alone group.

Another earlier trial randomly assigned 250 patients to Cisplatin alone or cisplatin plus Raltitrexed, a drug similar to pemetrexed (Alimta). The median survival was 11·4 months for the combination group compared with 8·8 months for cisplatin alone. Unfortunately, Raltitrexed is not available for treatment of mesothelioma, but the trial strengthens confidence in the validity of the result of the pemetrexed trial.

Median survival advantages are “averages”, and some patients whose mesotheliomas respond well to treatment gain more, while others whose mesotheliomas do not respond gain less.

The three large randomised trials undertaken so far suggest that Pemetrexed (Alimta), Raltitrexed, and Vinorelbine could have a role in mesothelioma treatment. They do not clarify the role of platinum, but earlier studies showed that some mesotheliomas respond to platinum, so there is reason to believe it may be of some value.