Exceptions or rule

“Cancer: shock breakthrough” was the headline on the 20^th June of The Independent newspaper in England. It was referring to a news release by Mayo Clinic researchers on 2 patients with advanced prostate cancer who had been given the human antibody called ipilimumab. (Ipilimumab binds to the cytotoxic T lymphocyte-associated antigen 4, a molecule on T cells that plays a critical role in regulating immune responses.)

These 2 patients had been participating in a clinical trial of over a hundred patients with advanced prostate cancer. In addition to receiving androgen-ablative therapy (treatment to remove testosterone availability in the body), these two patients were randomized to receive a single dose of ipilimumab intravenously. Their advanced prostate cancer responded dramatically to the treatment and went from an inoperable stage to a stage where surgery could be considered. In the end,  both patients underwent surgery and when the prostate tissue was submitted for pathological examination, the pathologist had a tough time finding cancerous cells in the prostate tissue.

Ipilimumab has been used in clinical trials for patients with advanced prostate cancer before. At the recent 2009 annual meeting of the American Society of Clinical Oncologists (ASCO), a poster presentation from the Memorial Sloan-Kettering Cancer Center in New York City, reported their experience with ipilimumab in 45 patients with metastatic castration-resistant prostate cancer. Ten of the patients had ≥ 50% reduction in the PSA level. In one patient the PSA level normalized and his metastatic lesions showed complete response.

In the medical world, occasional exceptional response to a new drug can happen during preliminary study. However, with further clinical trials, the new drug may turn out to be less effective than existing drugs or to have unacceptable side-effects. Ipilimumab may turn out to be a very effective drug for prostate cancer; however, we must wait for further bigger clinical trials before we can pass final judgement.

New promising drugs for treating advanced cancers are always welcome news for patients, their families and doctors. However, sensational headlines can sometimes lead to unrealistic expectations. When the drug fails to deliver the sensational response, the patient and his family members feel let down and ‘cheated’. Sensational headlines sell newspapers while premature sensational medical headlines cause disappointment.