For some people, having cancer means an automatic approval for disability benefits. Sometimes, the Social Security Administration will question a cancer case when they expect improvement after treatment. Even in these types of cases where improvement is expected, there may be complications or medical problems associated with the actual treatment for the cancer. In other words, even if you have improved after your treatment for cancer, you may suffer from the residual effects of surgery, chemotherapy, or radiation therapy. It will be necessary to obtain a medical opinion from your oncologist. Most Social Security judges are sympathetic to these types of cases, but they still may require proof of the residual effects of treatment for your cancer or a firm prognosis.