Pros and Cons of Breast Cancer and Biomakers Research Paper

Pros and Cons of Breast Cancer and Biomakers - Research Paper Example Most of the tumor markers are produced by cancer cells and also normal cells, but are increased in cancerous conditions. These factors are found in tumor tissue, blood, urine and other tissues and fluids of the body in some patients with cancer. More often than not, tumor markers are proteins. (National Cancer Institute, 2012) More than 20 different tumor markers have been described and characterized and they are in clinical use (National Cancer Institute, 2012). While some are associated with only one type of cancer, others are associated with more than one type of cancer. However, there is no universal tumor marker that can detect any type of cancer. Tumor markers serve various purposes in cancer management like complementing diagnosis, prognostication, detection of recurrence, etc. However, there are certain limitations for the use of these markers. Thus, there are pros and cons to the use of tumor markers. In this essay, pros and cons of application of biomarkers or tumor markers in breast cancer management will be discussed. Application of breast cancer biomarkers The most common cancer affecting women all over the world is breast cancer and it has been estimated that about one million cases are diagnosed every year worldwide (Duffy et al, 2005). The main presenting features of the disease include lump in the breast, skin contour changes and nipple discharge. Asymptomatic cases may be picked up during routine screening tests. Definitive diagnosis is histopathology of the biopsy specimen. Several blood based biomarkers are available, but they do not have a role in the early diagnosis of the disease. For localized breast cancer, primary treatment is mastectomy or breast-conserving surgery and radiation. In invasive breast cancer, primary treatment is followed by hormone therapy or chemotherapy. These treatments have shown to reduce mortality related to breast cancer. Following primary therapy, the patients are followed up at regular intervals for surveillanc e. This includes clinical history, detailed physical examination, chest X-ray, mammography, biochemical testing and use of breast cancer markers. The intention is to detect recurrent disease at an early stage so that outcomes are better. This is one use of tumor marker. There are other uses of tumor markers in breast cancer management. Recurrent disease is common even in lymph node-negative cases and therapeutic options in such cases include exclusive hormone therapy or chemotherapy or a combination of both. Metastatic breast cancer is considered incurable and treatment is mainly palliative. Serial assessment of tumor markers is useful in to decide whether a particular treatment modality can be continues or there is a need to switch to another treatment modality. Thus, it is now clear that tumor markers are necessary for optimal management of breast cancer (Duffy et al, 2005). Pros of breast cancer biomarkers There are 2 types of tumor markers available for breast cancer and they ar e serum markers and tissue markers. Examples of serum markers useful in breast cancer include CEA, CA 15-3, polypeptide antigen or TPA, BR 27.29, tissue polypeptide specific antigen or TPS and the shed form of HER-2 (Duffy, 2006). Examples of tissue markers include urokinase plasminogen activator, HER-2, hormone receptors and plasminogen activator-1. Most of the oncological organizations in Europe, US and other countries recommend routine assay of progesterone and estrogen receptors on all newly diagnosed breast cancers to select the type of hormone therapy (Duffy, 2006). These markers are also useful to determine prognosis. HER-2 is also recommended on all newly diagnosed breast cancer cases. The main purpose of this is to determine whether the cancer is suitable for Trastuzumab (Herceptin). This test is