India gets blood test to detect hidden cancer after treatment

MedGenome has launched OncoTrack MRD, a tumour-informed blood test for monitoring residual disease in solid cancers. The test adds molecular tracking alongside scans, though doctors must interpret results with clinical context and separate validation data.For cancer patients who have completed treatment, one of the most difficult questions is often not whether the tumour has disappeared on a scan, but whether a microscopic amount of cancer is still hiding somewhere in the body.A new blood test launched in India aims to answer that question at the molecular level.MedGenome, an Indian genomics and precision diagnostic company, has launched OncoTrack MRD, a personalised, tumour-informed molecular residual disease test designed specifically for solid tumours.While molecular residual disease (MRD) testing has been used in India for several years in blood cancers such as leukaemia, this marks the entry of an Indian-developed MRD test for solid cancers such as breast, colorectal, lung, ovarian and pancreatic cancers. An independent diagnostic expert described it as a significant step, saying it was, to his knowledge, the first such example from an Indian company.The latest launch comes against the backdrop of a burgeoning cancer burden in the country. As per Globocan 2024 by the World Health Organisation – International Agency for Research in Cancer (WHO-IARC), India registered 15.6 lakh new cancer cases that year while 33.2 lakh people with the disease were living in the country.WHAT DOES MRD MEAN?MRD refers to the tiny amount of cancer that may remain after apparently successful treatment but is too small to be detected through conventional imaging or routine clinical assessment. These residual cells can potentially seed a recurrence.The new test uses circulating tumour DNA (ctDNA) – fragments of DNA released by tumour cells into the bloodstream. But unlike a generic blood test, OncoTrack is tumour-informed: the patient's original tumour tissue is analysed first to identify roughly 50–100 mutations that form a personalised molecular "fingerprint."Subsequent blood samples look for that fingerprint using ultra-deep sequencing. MedGenome says its analytical sensitivity has been validated down to 50 parts per million.The baseline test therefore requires archived tumour tissue as well as blood. Once the molecular fingerprint has been created, follow-up surveillance requires only blood.The price is slated to be about Rs 40,000 for the baseline test and around Rs 20,000 for subsequent blood tests, according to information provided by the company.WHAT SCANS CAN MISSPositron emission tomography (PET) scans, computed tomography (CT) scans and magnetic resonance imaging (MRI) remain indispensable because they show doctors where a tumour is, its size and its relationship with surrounding structures.But imaging has a fundamental limitation: a lesion has to reach a certain size or biological activity before it can be reliably visualised.MRD testing looking at a different level. Instead of asking, "can we see a tumour?", it asks, "can we detect molecular evidence that this particular patient's cancer may still be present?"The diagnostic expert explained that this could potentially pick up tumour-derived DNA before a recurrence becomes visible on imaging, while also allowing doctors to compare molecular levels over time.MedGenome says the test is intended to complement imaging rather than replace it.According to the diagnostic company's CEO, Vedam Ramprasad, the personalised and ultrasensitive next-generation sequencing (NGS)-based tumourinformed MRD test answers these questions by adding an important layer of molecular insight to complement existing clinical assessment and imaging.Dr Niti Raizada, principal director-medical oncology at Fortis Hospitals in Bengaluru, opined that "tumour-informed MRD testing offers clinicians a powerful tool" to identify patients who may need closer surveillance or earlier intervention.That could eventually change follow-up from a largely scan-driven exercise into something more continuous: test, monitor the molecular signal and investigate a rising signal before a recurrence becomes clinically obvious.NOT ANOTHER CANCER SCREENThis distinction is crucial because India has recently seen the launch of blood-based multi-cancer early detection (MCED) tests.For example, Shield MCD, launched in India by Zydus Lifesciences and Apollo Hospitals and also at Dr Dang's Laboratories is aimed at adults aged 45 and above who are at average risk and attempts to detect signals associated with 10 cancers in people who have not already been diagnosed with cancer.A positive result still requires imaging, endoscopy or biopsy, while a negative result does not rule out cancer.OncoTrack works at the opposite end of the cancer journey. It is not meant to find cancer in a healthy person. The cancer has already been diagnosed, the tumour tissue has been characterised and treatment has been given or is under way.The test then looks for evidence of residual or returning disease.A veteran diagnostic expert described this as the prognostic side of cancer testing, distinct from screening and from theranostic testing, which determines molecular characteristics that can help identify targeted treatments.THE IMPORTANT RIDERSThe technology is promising, but a blood test detecting molecular traces of cancer is not the same as proving that a patient will relapse.An MRD-positive result may indicate residual disease and a higher risk of recurrence, but doctors still need to interpret it alongside the cancer type, stage, treatment history, symptoms and imaging.Conversely, an MRD-negative result means no tumour signal was detected within the test's sensitivity limits; it does not guarantee that cancer will never return.There is another important caveat.While MedGenome has cited studies such as GALAXY, IMvigor011 and ADAURA that support the broader role of tumour-informed ctDNA in cancer monitoring. But those studies do not, by themselves, constitute clinical validation of this particular Indian test.The diagnostic expert, quoted above, stressed that the company's own sensitivity, specificity and clinical-outcome data need to be examined separately. He nevertheless called the development "a step in the right direction."- EndsPublished On: Sep 4, 2026 14:04 IST