Radiation-Induced Sarcoma

While roughly 60% of cancer patients will be prescribed radiation therapy for their affliction, this treatment can come with an unwanted byproduct. A small percentage of patients later get diagnosed with a new form of cancer: radiation-induced sarcoma. If you’ve been prescribed radiation, you may feel better about it if you first speak to your doctor about this type of cancer. However, the following should serve as a helpful introduction.

Radiation and Sarcoma

Back in 2007, a study was carried out in the UK that looked at the approximately 298,000 new cases of cancer registered. Of those, it was estimated that some 1,346 cases were somehow associated with radiation therapy related to a previous type. This works out to be just 0.45%. As you can see, then, radiation-induced sarcoma is extremely rare (keep in mind that the percentage we just listed represents all forms of radiation-induced cancer, not just this particular kind of sarcoma). Nonetheless, because it is so lethal, you want to take it very seriously.

It’s also worth pointing out that there is no one definition accepted for radiation-induced sarcoma. While it would seem that any cancer originating from radiation treatment for a previous type should fall under this category, different doctors have chosen to characterize it different ways.

Risk Factors

Obviously, one major risk factor for this type of cancer is having a previous type and using radiation to treat it. Still, it may help to know about those forms of cancer that carry the highest risk of leading to radiation-induced sarcoma after getting treated. They are:

• Lung cancer
• Esophageal cancer
• Female breast cancer

Young patients may also be at greater risk, especially those who received radiation therapy as a treatment for Hodgkin lymphoma. Patients who underwent radiation and chemotherapy with alkylating agents may also face a greater risk of radiation-induced sarcoma. Some genetic constitutions may predispose a person to second cancers as well.

Treating Radiation-Induced Sarcoma

As is often the case with cancer, the primary method for dealing with radiation-induced sarcoma is surgery. Unfortunately, this cancer comes with rather large tumors (“high-grade”) that also plant themselves quite deep. Add to that high histologic margins following surgery and you get some unfortunate relapse and mortality rates.

For this reason, aggressive tactics during surgery are almost always justified in order to remove the radiation-induced sarcoma tumor as much as possible.

The other thing that can sometimes make treatment difficult is the long latency periods associated with radiation-induced sarcoma. It’s not as though the patient begins showing signs immediately after their first dose of radiation. Instead, it could be as long as 10 years before symptoms of radiation-induced sarcoma arrive.

Increased Prevalence of Radiation-Induced Sarcoma

Though it remains a rare form of cancer, there is some reason to believe that incidents are actually increasing. Many believe this has more to do with improved rates of survival in irradiated patients though, thanks in large part to systemic chemotherapy and, of course, greater occurrence of therapeutic radiation.

This is especially true with breast cancer. Not only is radiation being used more and more for breast conservation, but also for breast malignancy. On top of that, more women are being screened for breast cancer, resulting in earlier diagnosis and greater survival rates.

Survival Rate

Radiation-induced sarcoma is extremely aggressive and the survival rate is not good. However, it also comes with an extreme variance, with estimates ranging from 17% all the way up to 56%.

Source:

http://sarcomahelp.org/radiation-induced-sarcoma.html