Cancer is a silent killer that creeps up on people. Currently ~50% of cancers are diagnosed at an advanced stage that is difficult to treat. To improve cancer treatment, we need to increase patient education about cancer symptoms and at the same time develop new ways to test for it. Patient education is the crucial element in this battle against cancer.
Generally speaking, patient awareness of asymptomatic conditions is poor. When asked about their risk of getting cancer, the vast majority believe that it is very low. They are shocked to learn that 40% of the population will be diagnosed with cancer at some time during their lifetime. Education about risk and vigilance of early symptoms is very important.
Public education programs are helping to get the message out there. In 2022, the UK saw the greatest number of patients seeking cancer screening in its history, leading to higher diagnosis levels at earlier cancer stages. The National Health Service (NHS) program was remarkably successful based on its targeted awareness program. In cases where cancer can be identified with physical screening, the NHS is aiming to diagnose 75% of cancers at stage I or II by 2028.
Physical Cancer Screening
Unfortunately, physical screening is only able to identify four types of cancer (breast, cervical, colorectal, and lung). Only 14% of cancer is identified based on a screening that is recommended by a doctor. Other forms of cancer must be identified by symptoms (many of which are only identified at late stage). There is clearly a gap in the current approaches that should be addressed.
Using Blood Tests To Detect Cancer
Going forward, we will increasingly use blood tests to identify cancer even before symptoms become apparent. These blood tests are often referred to as "liquid biopsies" or "circulating tumor DNA (ctDNA) tests." They work by detecting fragments of DNA that are shed by tumors into the bloodstream.
There are a number of companies evaluating blood testing including GRAIL, Guardant Health, Exact Sciences and Illumina. Recent developments suggest that GRAIL is leading these companies with the development of its Galleri test, which can be used to identify a wide array of cancer types (over 50!).
Galleri uses complex algorithms and machine learning to recognize patterns of genetic changes that are indicative of different cancer types. This enables the test to identify potential signals of early-stage cancers.
Based on analysis from this test, a report is generated indicating whether there are any indications of cancer-related genetic alterations. If specific patterns or mutations are detected, it suggests the presence of a particular type of cancer. While not perfect, it can detect cancers that have no recommended screening tests today.
GRAIL reported results from its evaluation of Galleri at the ESMO Congress last year. The test detected a cancer signal in 1.4% of 6621 people aged 50 years and over who were not known to have cancer, and cancer was confirmed in 38% of those with a positive test. Of 6290 people who were cancer free, 99.1% received a negative test result. Among those with a positive test result, the time to achieve diagnostic resolution (i.e. to find cancer or decide there was no evidence of malignancy requiring further investigation) was a median of 79 days. Among participants with a positive screening test, diagnostic resolution was achieved within three months for 73%.
Healthcare Professionals Would Work With Patients Based On Test Results
These tests are really good news for patients and are a potential game changer in the war on cancer. The tests put another tool into the arsenal of healthcare providers and offer patients new ways to identify this threat to their health.
Going forward, these companies will need to develop awareness of these tests and methods to deliver them to patients. GRAIL is already working with Quest and other employer programs to provide access to its test. Given the potential of these tests, it is suprising to find that there is very limited awareness within the medical community. In many cases, patients who use the test request it from the doctor - and the test has saved lives.
These approaches present another wrinkle in how cancer may be identified in the future. Until now, cancer screening could only be done in person. Now companies like Freenome are presenting patients with alternatives. CEO Mike Nolan said, “The pandemic has proven that patients want us to meet them somewhere else, in addition to the healthcare system,” he continued, highlighting Freenome’s aim to cater to patients via alternative points of care such as retail pharmacies, telehealth platforms and federally qualified health centers. Their blood test would allow patients to screen for colorectal cancer.
These dual developments are highly encouraging in the battle against cancer, which continues to be a silent killer. Patient awareness is increases along with methods that can be used to screen for a larger variety of cancer types. We haven't won the war against cancer yet, but this offers a chance to win a major battle.