Long Term Threat

Young cancer suvivors may face health risks later on in life, research says. A child diagnosed with cancer would have a fifty-six percent chance of surviving for 5 years in the 1970's. Today, that statistic has increased to almost eighty percent. Now doctors have noticed that these survivors seem prone to life-threatening medical problems later on in life. Recently performed studies confirms this and shows an increased danger of heart problems or a "second cancer".

About five percent of childhood cancer survivors actually get cancer again. While some tumors are from the initial, primary cancer, some are new tumors that are unrelated to the first cancer.To scientists this change suggests that the child's original treatment contributedto this or they have a genetic predisposition to have cancer more than once.
Recently, a study revealed that survivors of Hodgkin's disease (diagnosed between 1967 and 2000) had twice the number of deaths from heart attack as other people. Children and teens treated for Hodgkins had nineteen times the rate of deadly heart attacks later in life. These findings raise concerns about treatments of cancer, although this statistic of heart attacks that occur amoungst survivors are lower than that of the elderly.

The chance of developing sarcoma (within ten years of childhood cancer) is nine times as great amoung survivors than normal. Sarcoma is cancer of muscle, bone, and tissue that surrounds nerves. In addition, an unusually high number of brain tumors appear in survivors of childhood cancer, especially leukemia. These tumors (called gliomas), within a decade of surviving childhood cancer, would appear nine times the population average.Radiation therapy stands out as the leading cause in heart problems and second cancers. Past research showed radiation to the chest can damage coronary arteries, which increases the risk of heart problems. Within the studies of gliomas and sarcomas, the survivors that got radiation were three times as likely for sarcoma survivors and seven times as likely for survivors of a brain tumor to develop second cancers as opposed to survivors who didn't get radiation.

Although these are some problems that occur with radiation it is still an incredibly important treatment for cancer. Radiation is good at breaking DNA strands which helps to stop cancer but it can also mutate a gene that normally prevents a cell from overdividing. In the last twenty years doctors have learned how to focus radiation into small beams which helps by decreasing the field of radiation which, in turn, requires a higher dosage, although we can't truely know if this helps limit second cancers.

Chemotherapy also can damage DNA. In the study of sarcoma certain kinds of "chemo" doubles the risk of having a second cancer. Researchers have found that in the case of Hodgkin's disease survivors, their increased heart attack risk can be attributed to radiation and chemotherapy. Though they have discovered this information about Hodgkin's, they still don't know the role of genetics and it contribution to second cancers. Although they do know that genetic mutations reduce a cell's production of enzymes that repair radiation damage that might lead to a possibility of the person getting a second cancer. The good news, though, is that a generation ago, having childhood cancer would mean death, now the only challenge is making sure the cure has as little risks as possible.

http://sciencenews.org/articles/20070310/bob11ref.asp

This article is interesting because I personally have never thought about second cancers and how they develop. I think it is interesting that prior treatments to the first cancer can affect whether a second cancer develops. I just thought that it was the primary cancer coming back and possibly spreading or that it was from a family gene but not from a treatment that is supposed to help with cancer.