MANILA, Philippines - Collateral damage. In contemporary parlance, this refers to negative incidental or secondary effects of a maneuver. But while in the past, this was customarily used in relation to military operations, its use has become colloquial so that it is now applied in relation to a variety of situations.
In the matter of breast and other types of cancers, the damage to surrounding healthy cells in the course of destroying the cancer cells may be referred to as collateral damage. Cancer treatment is a war against malignant cells where treatment modalities are dependent on the stage of the disease. Thus, it is expected that as the cancer becomes more advanced, stronger medicines are also employed. But because the usual oncology drugs are unable to distinguish between “good” and “bad” cells, all cells are harmed or destroyed during the course of treatment. Consequently, there is a magnification of negative side effects and deterioration of a patient’s quality of life.
Fortunately for some advanced breast cancer patients, targeted cancer therapy is now an option that can significantly improve survival rates. “The objective of targeted therapy is to stop the signaling system of cancer cells,” says Dr. Antonio Villalon, top medical oncologist and Cancer Institute director of the St. Luke’s Medical Center.
Dr. Villalon explains that targeted therapy entails interfering with the cellular processes of individual cells and depriving them of the signals for cancer activity. “Targeted cancer therapies are designed to slow or stop the growth of cancer cells. These types of therapies are more precise, so that there is less damage inflicted on surrounding normal cells.”
One such drug that acts on the principle of targeted therapy is Lapatinib, manufactured by pharmaceutical firm GlaxoSmithKline. By inhibiting tyrosine kinase, an enzyme in cancer cells that is identified as responsible for tumor growth, the drug slows down the course of the disease. Lapatinib was approved in first line, postmenopausal, hormone-positive, ErbB2-positive metastatic breast cancer therapy in combination with an aromatase inhibitor.
“This is a milestone drug that allows us the option of a non-chemo therapy regimen to select population of breast cancer patients,” says Dr. Villalon. He clarifies that not all breast cancers are responsive to targeted cancer therapy, and Laptinib is specifically indicated for the population positive for HER2/neu. “This is a tumor receptor status called human epidermal growth factor receptor 2,” Dr. Villalon elucidates. “Between 20 and 25 percent of the population who have breast cancer are HER2/neu positive.” The drug is the first and only oral treatment of its kind for this sector of breast cancer patients that significantly slows down the progress of advanced breast cancer in patients whose disease has progressed following treatment with other cancer therapies.
Although Dr. Villalon defers revealing the cost of the drug, manufacturer GlaxoSmithKline(GSK) has announced that the price of the targeted therapy drug Lapatinib is reduced by 40 percent under its Value Health program. Value Health was established in response to the need for more Filipinos to have access to high quality and affordable medicines.
The sad truth is that despite awareness drives, breast cancer continues to be diagnosed only when the disease has reached advanced stages. Statistics indicate that around six percent of breast cancers are metastatic upon diagnosis. This means that cancer cells have spread from a breast tumor to other parts of the body through the bloodstream or lymphatic system. The median survival time for women with metastatic breast cancer is placed at two to four years, with only one in five women surviving beyond five years. Definitely, ongoing efforts to promote breast cancer education and prevention need to be amplified and supported.