Trastuzumab Overcomes Breast Cancer

Breast cancer is the biggest 'killer' after heart disease. Breast cancer is also known to be the leading cause of death in women. Various studies are often conducted to find the best treatment technology to overcome this deadly disease. The latest news, breast cancer sufferers now have a new alternative for therapy other than chemotherapy. The new therapy is trastuzumab, which is a cancer therapy that directly targets the genes that cause breast cancer.

“So far, one of the main things that cancer patients have to go through in the treatment process is chemotherapy. Unfortunately, chemotherapy has several drawbacks, for example the drugs used in chemotherapy so far not only destroy cancer cells, but also normal cells and tissues of the patient. "So that it can cause unpleasant side effects such as hair loss, mouth sores, diarrhea, and blood disorders," said Dr. Targeted Therapies for Breast Cancer in Bandung, some time ago. During the event, trastuzumab therapy, which is a biotechnology product, was officially launched.

Not just any cancer patient can follow this therapy. ''The prerequisite for trastuzumab treatment is the HER2 test. If HER2-positive is found, the patient can be treated with trastuzumab,'' explained Dr Bethy Hernowo Sp PA (K) PhD, one of the speakers at the symposium.

HER2 is an acronym for human epidermal growth factor receptor 2, namely the human growth factor receptor. HER2 is a protein found in large quantities on the surface of breast cancer cells.

The role of HER2 is as an antenna that receives signals for cancer cells to multiply quickly and kill. Therefore every breast cancer patient apart from being routinely examined for estrogen and progesterone receptors, it is also highly recommended to be examined for HER-2.

According to Dr Bethy, there are two ways to examine HER-2/neu, namely Fluorescence In Situ Hybridization (FISH) and Immunohistochemical (IHC) examination. FISH examination was carried out using a fluorescence-labelled DNA probe for HER-2 on chromosome 17 and CEP 17-chromosome enumeration probe for chromosome 17. So that the ratio between the orange signal (genHer-2) and the green signal (centromer 17) will be evaluated. While the IHC examination uses a commercial anti-HER-2/neu monoclonal antibody with the principle of antibody bonding which is colored. The IHC operation is easier and less expensive than the FISH operation and has become the standard for HER2.

It takes only five hours so results can be provided to the clinician in one to two days (repeat is not necessary). In Indonesia, IHC examinations can already be carried out in Jakarta, Bandung and Yogyakarta.

For the preparation of tumor tissue in IHC, it is done by taking fresh tissue, tissue with formalin fixation, and tissue in paraffin (paraffin block). If the delivery distance is short, the tissue in formalin is put into a container to be sent. However, if the distance is long, the tissue in formalin or paraffin blocks is sent via postal packets. ''The use of the HER2 test is prognostic for new patients and selection of therapy that is specific endocrine therapy, specific chemotherapy regimens, and trastuzumab therapy,'' said Dr Bethy.

How trastuzumab works Trastuzumab produced by PT Roche Indonesia has several functions, namely blocking tumor cell growth, immune signaling and working with chemotherapy. Herceptin and chemotherapy work in different ways, but together they work synergistically.

Currently trastuzumab is given to patients with advanced (metastatic) mammary carcinoma and shows overexpression of the HER2 protein, although it is also given to early-stage carcinoma.

In a clinical trial of 235 patients who received itrastuzumab along with chemotherapy, tumor growth slowed down and decreased by 50%. Of the 222 women who took this therapy, as many as 14 percent experienced shrinkage of the tumor and in 3% of women the tumor disappeared. This response occurs within six months to 18 months after therapy ends. Median survival was 25 months on this therapy compared to 20 months in women without trastuzumab.

With such positive results, it is hoped that this therapy can help breast cancer sufferers, which is the main cause of death in women. According to WHO data, eight to nine percent of women will experience cancer in their lifetime. It is estimated that 1.2 million women worldwide suffer from breast cancer. After undergoing treatment, about 50 percent of patients progress to end-stage breast cancer with a survival rate of 18 to 30 months.

Although there is no definite data in Indonesia regarding how many Indonesian women suffer from breast cancer, the data can be seen in cases recorded in hospitals. One of them is at the Hasan Sadikin Hospital which records as many as 90 to 100 cases of breast cancer per year.

"Data collection is very difficult due to various factors, including because most of our people are urban people who are always on the move, so it is difficult to collect data," said Dr Dradjat.

Dr. Bethy hopes that the HER2 examination will be more socialized through clinicians, oncologists and pathologists about the importance of and its relation to trustuzumab therapy. ''Hopefully this will be realized with good cooperation between doctors and pharmacies so that sufferers will receive optimal management,'' he hoped.

Source: www.republika.co.id