Wednesday, July 8, 2009

New from ASCO - Update by Dr Wong Seng Weng on Breast Cancer Treatment

New treatments

New class of "smart drugs" with promising new results in treating "resistant" forms of breast cancer.

Results announced in the American Society of Clinical Oncology Annual Meeting in Orlando 29 May-2Jun 09: PolyADP-ribose polymerase inhibitors (PARP inhibitors).

"Smart drugs" (targeted therapy) in cancer are like "smart bombs" in warfare. They zoom in to hit the cancer cells by incapacitating cancer cells by way of recognition of unique targets on the cancer cells thereby avoiding harm to the normal cells of the body. Advances in the use of anti-cancer antibodies and hormonal therapy are examples of such targeted therapy in breast cancer in recent years.

However, there is a significant percentage of breast cancer types that do not display such targets and are resistant to these new treatments methods. These breast cancer types are described as "triple negative" ie negative for the 3 common targets that "smart drugs" in breast cancer go after.

Patients with these form of breast cancer tends to have a poorer prognosis due to the greater resistance of these cancers to treatment and they tend to afflict younger breast cancer patients.

Research has revealed a new vulnerability of these cancer types. They have an impaired ability to repair any damage to their genetic material which is critical to their survival. The new class of targeted drugs (PARP inhibitors) are able to jam this vulnerable repair mechanism thus increasing the damage chemotherapy cause to these cancer cells improving the results of treatment.

Dr Wong Seng Weng
MBBS (Singapore), MRCP (UK), FAMS (Medical Oncology)
Consultant Medical Oncologist & Physician
The Cancer Centre, Paragon Medical