Doctors’ ignorance is very dangerous for patients; most physicians cannot keep up with accelerating progress of science. Most general practitioners, and even oncologists, frequently ignore the scientific evidence as they wait until this knowledge will be adopted in clinical practice elsewhere, and they will be willing to prescribe new medications and tests only after they become mainstream. This means that the most of the cutting edge science is staying out of common clinical practice thus leaving their patients at risk. Confounding this problem is the fact that most people prefer not to know that they might a higher risk of developing cancer due to previous family history of the disease. Some people are naively thinking that the “ostrich strategy” will somehow protect them, but as I explained earlier, it is much better to know about the increased risk of debilitating disease rather then remaining oblivious. Therefore, I am advocating for more broad cancer screening and genetic testing which can substantially improve the accuracy of cancer diagnosis and treatment. For example the PSA is very common biomarker for prostate cancer which has been recently dis-recommended for clinical screening due to poor specificity (i.e. how likely that patient with high PSA level is going to develop an aggressive tumor). However with addition of simple genetic test, the clinical specificity of PSA can be substantially improved, particularly in countries with large ethnic diversity such as the UK. Ethnicity plays important role as specific genetic variations may drive higher levels of PSA that are not associated with the risk of cancer. PSA has better predictive value in ethnically homogeneous population where genetic diversity is lower– for example the predictive value of PSA is almost 70% in Iceland, but the PSA alone is much less accurate in UK (~55%). The genetic “correction” of PSA values improves the PSA specificity by more than 6.5% for UK men and 2.8% for Icelandic men. It might seem not much of an improvement, but in a large scale population screening these numbers are very significant, highlighting the importance of additional genetic testing on tumor samples. New cancer biomarkers are being discovered, but simultaneous testing with multiple biomarkers greatly improves overall specificity. Before taking on testing both physicians and patients have to realize what is test’s specificity and sensitivity – this knowledge will help to manage anxiety around cancer diagnosis. After discovering the tumor it is essential to analyze its nature and “signature” – different types of cancer require different treatment approaches. Deep tumor sequencing can identify novel pathways playing roles in tumor development and progression hinting on new therapies. For example most recent report on pancreatic cancer identified mutations in the ROBO/SLIT pathway, which is responsible for axon guidance that might have lead to the dis-balance in Wnt signaling. Wnt is a known player in cancer that regulates stem cells that are the root of cancer. Stem cells are special cells that are important for tissue renewal. As stem cells divide they differentiate into various cell types that comprise complex tissues. Differentiation also reduces the proliferation potential, but mutations that prevent stem cell differentiation lead to cancer where a mass of poorly differentiated cells reproduces uncontrollably. Genetic analysis also identified specific genes altered in endometrial cancer, whether yet another set of genes is important. This study identified that 17% of endometrial tumors had mutations in the CHD4 gene, which is one of chromatin regulating factors. The chromatin regulating genes such as TP53, PPP2R1A and PIK3CA, Rb, and the CHD4 regulate DNA replication and repair. So as you can imagine defects in different pathways may lead to various forms of cancer each of which requires different treatment approach. In a very simple summary the MIT technology review illustrates the power of cancer genomics. By knowing the underlying genetic causes of each cancer, it is possible to find specific drugs that help to either ameliorate the damage or use it to kill the cancer cells more specifically. There are many examples of specific cancer therapies, one of which is Herceptin – specific antibody that blocks signaling of mutated growth factor receptor (EGFR, aka HER) that is present in some breast cancers. Such targeted treatments help to reduce the toxicity and severe side effects and prolong patient survival. Steve Jobs’ life was substantially prolonged with the use of tumor sequencing technology and targeted treatment ( as described in his biography). Despite huge benefits of personalized medicine in cancer, it is important to realize that cancer is incurable. Clonal nature of cancer where each cell mutates with every division makes it much more difficult to treat the disease – killing the bulk of the tumor helps to keep it under control but these treatment most of the time cannot kill every cancerous cell, therefore there is a constant danger of relapse. Personalized Medicine allows to optimize the treatment and stay “ahead of the game”, but not to cure the disease. Therefore, predictive genetic testing is important as it helps to identify people who are at risk, start regular monitoring and diagnostic testing and begin preventive treatments before disease progresses to an uncontrollable stage. As with any disease, cancer is managed when detected early; such early detection is key for finding small tumors that are smaller, less aggressive and more homogenous. There is still huge controversy whether cancer screening is justified as increased screening leads to over treatment. This is real problem but again better an more accurate diagnosis can be enabled by prognostic biomarkers such as OncotypeDX that identified women who are at higher risk of metastatic disease and need chemotherapy, but in most cases women with milder scores are spared toxic treatments. Another way to improve outcomes of cancer therapy is by chemortherapy response testing developed by the RNA Diagnostics – this test shows whether patient responds to chemotherapy or needs alternative regime without waiting several months. Another useful testing monitors patients in remission for circulating tumour cells allowing to catch relapse very fast before metastasis grow up substantially. The fear factor is quite paralyzing. I was astonished to find that some people prefer “not to know (now)” about the risk of even preventable and treatable diseases, just because they fear the emotional stress of getting “bad news”. So probably genetic testing is not for faint hearted individuals. Nevertheless, when people are really pressed “against the wall” and have to make a decision, most of them make the right choice and take dramatic steps to prevent the disease onset/progression. Foe example Sharone Osborne did double mastectomy after fighting off a bout of colon cancer, and discovering the genetic predisposition. All these tools now help manage cancer by far more effectively, but again show promise most for patients at early stages of disease. Most of therapies work better on diseases in their early stages even for Alzheimer’s. So, my dear friends, do not behave like a bunch of scared ostriches! Think about your family and friends and begin acting responsibly! Let your doctors use all the advanced technology. Take control of your health; be proactive in controlling your diet, exercise (yes, the painful 10,000 steps a day). Educate yourself on disease diagnostics; confront your doctors if you feel that they do not pay enough attention to your health and come prepared. P.S. John Dick published a study that emphasizes the difficulties of treating cancer – after all each clone of tumour cells responded differently to chemotherapy. http://www.reuters.com/article/2012/12/13/us-science-cancer-dna-idUSBRE8BC19620121213?goback=%2Egde_1955429_member_195995808

Try now

Join our newsletter

  • Stay connected to insightful articles and blog posts
  • Stay in the loop with the latest news
  • Receive special offers on GeneYouIn products!


Please select areas of interest:
 Drug response
 Inherited disease predisposition
 Fertility
 Cancer
 Mental Health
 Healthy Living

GeneYouIn Inc. © 2012-2017. All rights reserved