A newly developed blood test is currently being regarded as the noninvasive alternative to biopsy, which is the gold standard in cancer diagnosis.

Biopsy, although considered as the most reliable method in detecting cancers, is an invasive procedure that entails health risks. Aside from these, the procedure is costly and time-consuming, which are some of the things that patients cannot tolerate. With the new blood test developed by Pathway Genomics Corp., patients are saved from all these hassles and more.

Dubbed "liquid biopsy," the emergent diagnostic method involves searching for the presence of the genetic substances released by tumors known as the circulating tumor DNA. In a study conducted at the Royal Brompton Hospital and Imperial College London, a group of researchers led by Dr. Eric Lim, a thoracic surgeon from the Royal Brompton and Harefield National Health Service (NHS) Foundation Trust, tested 223 preoperative patients with confirmed and suspected primary and secondary lung malignancies. After the tests, the scientists found that the liquid biopsy procedure was able to yield a 70 percent accuracy rate in detecting cancer cells.

The emergent diagnostic procedure is yet to be considered as a substitute for biopsy. Nonetheless, testing positive for this test would conserve time and allow prompt treatment. With this, treatment outcomes may be more enhanced as it can be started sooner than the release of biopsy results.

Various diagnostic methods for detecting cancer currently exist. The choice as to which procedure should be performed depends on numerous factors such as the location of the suspected tumor, the tolerance of the patient and choice of the clinician. Existing methods for cancer screening include:

Magnetic Resonance Imaging (MRI)

MRI is a diagnostic method that utilizes magnetic fields to formulate precise digital images of organs and tissues. This test is typically prescribed in patients with suspected tumors in the abdomen and chest.

Computed Tomography (CT) Scan

Also known as CAT Scan, this procedure is performed not only to identify the presence of tumors, but also to determine the stage of the disease and the occurrence of spread. This test is also used to evaluate the outcomes of cancer therapies.

Positron Emission Tomography (PET) Scan

PET scan is a diagnostic imaging test that uses radioactive agents to visualize tumors and determine the stage of the disease and treatment prognosis.

Ultrasound

Ultrasound is aided by high-frequency sound waves to depict internal organs. As tumors exhibit echoes and normal tissues do not, the sound waves sent to the tumors will bounce back to the computer screen as a tumor image, which the clinicians will be able to view.

Bone Scan

Bone scan is prescribed for patients with suspected cancer of the bone. Aside from this primary indication, this test may also be required to see if cancer cells from different organs have already spread to the bones.

Tumor Markers

Also called biomarkers, these substances are being produced in higher amounts by patients with cancers. These agents may be detected in the blood, some tissue samples and urine.

Barium Enema

Barium enema is recommended for patients with suspected lower gastrointestinal cancers. Barium actually pertains to a special dye that is injected to the colon and rectum via the anus. After instillation, the contrast medium will show up as a white image upon x-ray, outlining the entire tract and visualizing any abnormalities including tumors, polyps and inflammations.

Photo: Lee Haywood | Flickr