A newly developed device can detect and analyse cancer cells from blood samples, and do away with the need for invasive biopsy surgeries. The device, developed by researchers from the University of Technology, can also help doctors monitor the treatment process. 


The study describing the device was recently published in the journal Biosensors and Bioelectronics. 


According to the United States National Institutes of Health (NIH), the estimated number of incident cases of cancer in India in the year 2022 was found to be 14,61,427. One in nine people in the country are likely to develop cancer in their lifetime. 


Existing techniques for cancer diagnosis


Currently, cancer is diagnosed in three ways: laboratory tests, imaging tests and biopsy, according to NIH's National Cancer Institute. 


When a person is suspected to have cancer, they often require surgery for a definitive diagnosis.


The laboratory tests to diagnose cancer can detect the levels of certain substances in the body, which could be a sign of cancer. Tests of the blood, urine and other body fluids measure these substances. However, abnormal test results do not necessarily indicate cancer. Also, a person might have normal test results even if they have cancer. Therefore, biopsies and imaging tests are also conducted to ensure accurate diagnosis. 


The different types of laboratory tests include blood chemistry tests, which measure the amounts of substances such as metabolites, fats, sugars, electrolytes and proteins, and give important information about how well one's organs are working; complete blood count, which measures the number of red blood cells, white blood cells, platelets, and haemoglobin in the blood, and can help diagnose cancers such as leukaemia; cytogenetic analysis, which looks for changes in chromosomes in samples of tissue, blood and bone marrow, and can identify signs of a genetic condition that may be associated with cancer; immunophenotyping, which uses antibodies to identify cells based on the types of antigens; sputum cytology, which looks for abnormal cells in the sputum; liquid biopsies, which are conducted on blood samples to look for cancer cells or pieces of DNA from tumour cells; tumour marker tests, which measure substances produced by cancer cells or other cells in response to cancer; urinalysis, which describe the colour of urine and measure its contents; and urine cytology, which looks for abnormal cells shed from the urinary tract into the urine. 


The imaging tests used to diagnose cancer intend to check whether a tumour is present. The techniques include computed tomography (CT) scan, magnetic resonance imaging (MRI), nuclear scan, which uses radioactive material to capture pictures of the inside of the body, bone scan, which is a type of nuclear scan specifically used to check for abnormal areas in the bones, ultrasound, and X-rays.


Biopsy is a procedure in which a sample of abnormal tissue is removed, observed under the microscope, and tested. Biopsies are mostly invasive, because they are conducted using a needle, and with endoscopy and surgeries. 


Disadvantages of biopsies


A biopsy can cause discomfort to patients, and lead to an increased risk of complications due to surgery, Professor Majid Warkiani, one of the authors on the paper, said in a university statement. Moreover, surgeries are expensive procedures. 


Warkiani said managing cancer through the assessment of tumour cells in blood samples is far less invasive than taking tissue biopsies. Also, the analysis of blood samples allows doctors to conduct repeated tests and monitor a patient's response to treatment. 


What is the new device called?


The device, called the Static Droplet Microfluidic device, can rapidly detect circulating tumour cells that have broken away from a primary tumour and entered the bloodstream. The device differentiates tumour cells from normal blood cells using a unique metabolic signature of cancer.


How does the new device work?


Warkiani said that in the 1920s, Otto Heinrich Warburg, a German physiologist and the sole recipient of the 1931 Nobel Prize in Physiology or Medicine, discovered that cancer cells consume a lot of glucose, and hence, produce more lactate, which is acidic in nature. The device, Warkiani explained, monitors single cells for increased lactate using pH sensitive fluorescent dyes that detect acidification around cells.


Warkiani said a single tumour cell can exist among billions of blood cells in just one millilitre of blood. This makes it difficult to find tumour cells. 


Warkiani explained that the new detection technology has 38,400 chambers capable of isolating and classifying the number of metabolically active tumour cells. 


After the device has identified the tumour cells, genetic and molecular analysis is conducted. This can help in the diagnosis and classification of the cancer and help doctors devise personalised treatment plans. 


How is the new technique better than liquid biopsies?


Metastasis is the cause of 90 per cent of cancer-associated deaths. In metastasis, cancer migrates to distant organs. 


Circulating tumour cells, which are precursors of metastasis, can provide insights into the biology of cancer metastasis.


While liquid biopsies are an already existing technique, they are not always reliable when it comes to diagnosing cancer. Also, they are time-consuming, expensive and depend on skilled operators. This limits their application in clinical settings. 


According to the study, the new technology is designed for integration into research and clinical labs without relying on high-end equipment and trained operators, and will enable doctors to diagnose and monitor cancer patients in a practical and cost-effective manner. 


The researchers plan to commercialise the Static Droplet Microfluidic device.