Testing for Tumor Mutations: Liquid Biopsy Versus Traditional Biopsy


Liquid biopsies, virtually unknown even a year or two ago, are becoming common tools in precision diagnostics for cancer. Here, I will try to explain some of the more important differences between liquid and “traditional” tumor biopsies.

Biopsies of solid tumors (e.g., lung, breast, or brain tumors) involve surgically removing a small part of a tumor and sending it to pathology lab. In the last few years, doctors have also started to send some tumor samples to special service labs that analyze tumor DNA for the presence of cancer-related mutations.

By definition, regular biopsies can be intrusive and are sometimes associated with side effects, such as bleeding or infection. However, they provide some really essential information; i.e., the histology and grade of the tumor and other tumor characteristics necessary to determine the best choice of treatment. For lung cancer, for example, a biopsy determines the type of tumor—adenocarcinoma, squamous cancer, small-cell lung cancer, or another, less common type. For breast cancer, a routine test will determine if the tumor expresses estrogen, progesterone receptors, and a protein called HER2. These tests are critically important in guiding treatment choices. If mutational analysis of cancer-related genes is also performed (which doesn’t always happen, unfortunately), it may guide treatment with targeted drugs. Continue reading…


Blood Test Gives Early Warning of Melanoma Relapse

“A blood test can detect changes in tumor DNA, potentially helping doctors detect melanoma relapse far earlier, according to a study in England.

“Scientists at Cancer Research UK found the blood test detects mutations in circulating tumor DNA indicating potential drug resistance or relapse, which would allow treatment to start earlier and increase the chance for a patient’s survival.

“Although the study was small, and scientists say the test’s accuracy needs to be tested in a much larger trial before it is used in clinics, any possibility of improving how cancer is tracked will improve treatment.”


The Evolutionary History of Lethal Metastatic Prostate Cancer

“Scientists have revealed the root of prostate cancers in individual men, discovering that despite huge genetic variety between tumours they also share common gene faults – insight that could offer new treatment hopes, according to research published in Nature today (Wednesday).

“In a landmark paper, Cancer Research UK funded scientists alongside an international team of researchers read all of the DNA in tumour samples from 10 men with prostate cancer. This allowed them to map a ‘family tree’ of the changes happening at a genetic level as the disease spreads, forms new tumours, and becomes resistant to treatment.

“They also revealed more detail about how prostate cancer spreads, showing that the group of cells that first spread from the prostate carry on travelling around the body, forming more secondary tumours.”


Docetaxel Plus Ramucirumab Improves Outcomes in Advanced NSCLC

“The addition of ramucirumab to docetaxel improved outcomes over placebo with docetaxel as a second-line treatment of patients with advanced non-small-cell lung cancer (NSCLC), according to results of the REVEL trial presented at the 2014 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago.

“ ‘Despite advancements in genomics and identification of predictive biomarkers such as EGFR mutations or ALK rearrangement, there is still no… targeted therapy for the majority of patients with squamous and non-squamous carcinoma,’ said Maurice Pérol, MD, of the Cancer Research Center of Lyon in France. Ramucirumab specifically targets VEGFR-2 and inhibits angiogenesis, and it has been shown to improve outcomes in gastric cancer as monotherapy.”

Editor’s note: This article describes a treatment for advanced non-small cell lung cancer (NSCLC) that combines a new targeted drug called ramucirumab with the standard chemotherapy drug docetaxel. In a clinical trial to test the treatment in volunteer patients who had already received one previous treatment, it was found that ramucirumab plus docetaxel provided better patient outcomes than docetaxel plus a placebo.


US ‘Proof-of-Concept’ Trial Confirms Promise of Stratified Lung Cancer Treatment

“Routine tests that look for multiple, specific genetic changes in patients’ lung tumours could help doctors select targeted treatments, a US study has confirmed.

“The research, published in the Journal of the American Medical Association, looked simultaneously for ten specific cancer-driving genetic changes in the tumours of 733 patients with adenocarcinoma, the most common type of lung cancer.”

Editor’s note: Learn more about genetic testing and personalized approaches to lung cancer treatment in our Lung Cancer KnowledgeBase.


Results of Three Studies Indicate 17-Gene Assay Is a Significant Predictor of Prostate Cancer Aggressiveness at the Time of Diagnosis

“According to the results from three studies published in European Urology, the 17-gene Oncotype DX Genomic Prostate Score is a significant predictor of disease aggressiveness at the time of diagnosis before intervention with radiation or surgery. The test provides more precise and individualized risk assessment than currently available tools and may help physicians choose the most appropriate treatment for their patients.”

Editor’s note: Newly diagnosed prostate cancer patients face complex treatment decisions based on many different factors. One major consideration is the level of aggressiveness of the cancer, i.e. how fast the cancer is likely to grow and metastasize. A test called the Oncotype DX Genomic Prostate Score examines 17 tumor genes to determine aggressiveness, and new research results show that the test is effective. Learn more about the test.


Molecular Tumor Board Helps in Advanced Cancer Cases

With accelerating development of personalized cancer treatments matched to a patient’s DNA sequencing, proponents say frontline physicians increasingly need help to maneuver through the complex genomic landscape to find the most effective, individualized therapy.

Editor’s note: Learn more about personalized medicine and molecular (genetic) testing on our website.


Molecular Tumor Board Helps in Advanced Cancer Cases

With accelerating development of personalized cancer treatments matched to a patient’s DNA sequencing, proponents say frontline physicians increasingly need help to maneuver through the complex genomic landscape to find the most effective, individualized therapy.

Editor’s note: Learn more about personalized medicine and molecular (genetic) testing on our website.


Molecular Tumor Board Helps in Advanced Cancer Cases

With accelerating development of personalized cancer treatments matched to a patient’s DNA sequencing, proponents say frontline physicians increasingly need help to maneuver through the complex genomic landscape to find the most effective, individualized therapy.

Editor’s note: Learn more about personalized medicine and molecular (genetic) testing on our website.