The multiple sclerosis drug mitoxantrone may be associated with an increased risk of colorectal cancer, according to a study published in the May 11, 2016, the medical journal of the American Academy of Neurology. Mitoxantrone suppresses the immune system. It was first developed as a chemotherapy drug for certain cancers.
Mitoxantrone is used for aggressive types of relapsing-remitting or progressive MS that do not respond to other Multiple sclerosis drug. But its use is limited because previous studies have shown an increased risk of leukemia and heart damage.The current study examined whether the drug increases the risk of other types of cancer. For the study, German researchers looked at all people with MS who were treated with mitoxantrone from 1994 to 2007 and followed them until 2010.
Of the 676 people, 37 people, or 5.5 percent, were diagnosed with cancer after taking the Multiple sclerosis drug mitoxantrone , including nine people with breast cancer, seven with colorectal cancer and four with acute myeloid leukemia, which has been associated with mitoxantrone.The rate of leukemia was 10 times higher in the people treated with mitoxantrone than in the general population in Germany. The rate of colorectal cancer, which is cancer of the colon and rectum, was three times higher than that of the general population. For breast cancer and all other types of cancer, people who had taken mitoxantrone were no more likely to develop the diseases than those in the general population.
Of the seven people with colorectal cancer, three died from the cancer during the study. The four people with leukemia all went into remission after treatment and were alive at the end of the study.The researchers also looked at whether factors such as how much of the Multiple sclerosis drug people had received cumulatively and whether they also received other immunosuppressant drugs affected their risk of developing cancer. The only factor related to a higher risk of cancer was being older when starting to take the drug.