liquid-biopsy

Liquid Biopsy and its role in fighting cancer


Wrong diagnosis and wrong medications can lead to fatal results in person’s health. According to September 2014 bulletin of Sample Registration System (SRS), India has an infant mortality rate of 40 per 1,000 live births.Wrong drugs cause 50 deaths out of 1000 patients in India. Most of the times, a regular disease can exaggerate and become fatal because of the wrong diagnosis and medications. Same was the case with Mr. Deshpande (name changed) – which almost took a toll on his life.

When Mr. Deshpande, a 74 year old retired banker started suffering from abdominal pain, weakness, and fatigue, his wife was alarmed because he had always been very careful about his diet and exercise regime. Neither did he miss his regular check-ups. He wanted to lead his retirement exactly the way he had planned. However, all his plans were short lived because of his constant health issues after the retirement.

On the contrary, he also lost his weight drastically. When his wife took him to their GP, he referred them to an expert in the city where he was first diagnosed with adenocarcinoma of colon in November 2013.

After the diagnosis, the doctors suggested surgical resection which would be followed by chemotherapy. Doctors also advised a Positron Emission Tomography (PET) scan. This scanning is basically to check how the tissues and organs in the body are working. A year later,in November 2014, while testing, a mass measuring 2.1 x 1.7 cm was detected in the lung with speculated margins. The doctors assumed it as a metastasis from colon cancer and started with Capecitabine – a chemotherapeutic agent.

After the prescriptions, he was being continuously monitored with PET scans. However, despite of the chemotherapy which was ongoing since a year, the mass was continuously increasing in size.

Doctors were not sure if it was indeed a metastasis of colon cancer, or it was a result of tuberculosis or in a worse case, primary lung carcinoma?

After looking after a varied possibilities and options, he was referred for a liquid biopsy. However, Mr. Deshpande was reluctant because of general perception of the biopsies. He was only relieved when the doctors explained that the procedure is as easy as a simple blood test.

Liquid Biopsy showed mutation burden 4.4 % of total cell free DNA. It was an indication of active primary lung carcinoma. The Liquid Biopsy indicated therapeutic response to targeted anti EGFR therapies such as Afatinib, Gefitinib and Erlotinib.

Here, Gefitinib was prescribed to the patient. This drug is only effective in cancers with mutated and overactive EGFR. It started showing its results and the tumor began to shrink gradually. Repeat PET scan showed reduction in tumor size by 70%. That meant a great success of the accurate diagnosis and correct medications.

Liquid Biopsy after three weeks
Liquid Biopsy after three weeks

Five weeks later, detectable mutation burden in the cell free DNA obtained from plasma was negative. The mutation burden was reduced even more as compared to the previous analysis possibly due to Gefitinib therapy.

Mr. Deshpande is completely hale and hearty now. It’s interesting how one correct step towards the course of treatment can leave a huge impact on patient’s well-being.

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Neurology and pharmacogenetics

Pharmacogenetic analysis for Neurology/Psychiatry


Adverse Drug Reaction (ADR) is one of the most common causes of deaths worldwide. It also causes 50 deaths out of 1000 patients in India. These statistics highlight the importance of correct drugs for the treatment. This is where Pharmacogenetics plays an important role.

What is pharmacogenetics?

Pharmacogenetics is the study of inherited genetic differences in drug metabolism which can affect individual responses to drugs, both in terms of therapeutic effect as well as adverse effects.

Why pharmacogenetics?

In a last few years, importance of pharmacogenetics has increased tremendously in medical practice. This testing particularly benefits psychiatric patients as the drugs and medications suggested in the treatments can lead to variety of side-effects. The use of pharmacogenetic screening can help the expert to design psychotropic treatments and make informed decisions which prove to be very useful most of the times.

Many cases and studies have been published in recent times which prove the positive results in the patients. Along with the better outcome, genetic testing also helps to decrease the medical costs. Recently, many studies have been published demonstrating improved patient outcomes and decreased healthcare costs for psychiatric patients who utilize genetic testing.

The very first genotyping test used in psychiatry was Roche’s AmpliChip CYP450 test. It received clearance from FDA in December 2004.

The risk of adverse drug reaction is more in children and adolescents who have metabolic disorders as their system finds it hard to break down the new elements in it.

Pharmacogenetics is important in neurology / psychiatrics because –

  • It gives an insight of patient’s metabolic response
  • Prescribes surer, safer and targeted drug therapy
  • Promotes avoidance of Over-dose/ Under-dose
  • Minimizes Adverse Drug Reaction (ADR)
  • Eliminates trial and error in therapy
  • Offers optimum therapeutic response
  • It’s an affordable and once in a life-time test
  • It protects doctor from medico-legal complications

It is a common belief that high-end medical tests only prescribe equally high-end and expensive treatments. However, it is not the case; pharmacogenetic screening identifies the most effective course of conventional treatments and also suggests equally effective alternate options.

The widespread application and utility of pharmacogenetics in neurology/ psychiatry will only keep increasing along with its knowledge and understanding. With continuous research, it is very vital that medications and drugs will get more narrowed down on the basis of their effectiveness to the patients.

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