Medical science has developed effective, reliable screening procedures for only four types of cancer. Those cancer types are:
Breast—61% of breast cancers are discovered by mammography
Cervical—52% of cervical cancers are discovered by PAP Smears
Colorectal—45% of colorectal cancers are discovered by colonoscopy,
sigmoidoscopy, or fecal occult blood testing
Lung—3% of lung cancers are discovered by screening CT of the chest
Prostate cancer is another for which screening is done, but the methods used aren’t as consistently reliable as those listed above. It is encouraging information, however, because we all know the importance and benefit of finding cancers early when there’s a better chance of complete cure. BUT
A recent study reported that only 14.1% of all cancers diagnosed in the United States were found during a screening procedure. That means that the remaining 85.9%, a huge percentage, were found after the patient had symptoms or at a time when screening for cancer was not the focus of the evaluation. The “vast majority of cancer types do not have screening tests available.” So, those types of cancer go undetected due to the lack of a reason to start looking for them. Mammograms, PAP smears, and colonoscopies have been done on asymptomatic patients for years because the rate of cancer detection using them has proven to be positive. These screening procedures have impacted outcomes by improving cure rates through early detection.
We all know how effective these screenings are, but when it’s reported that only 14.1% of all cancers are diagnosed by screenings, it sends a chill up my spine. For all the effort to promote screenings by physicians, a paltry 14.1% detection rate is shockingly low. I guess this statistic means screening isn’t as effective as most people think, and doctors need to find a better way to screen for asymptomatic disease. Since Medicare and other insurers don’t pay for screenings, it makes it an expensive proposition to do total body screening when you don’t know what you’re looking for nor do you know where to look. Anything one finds is a lucky occurrence. There are many more empty work-ups than are there cancer detections. Patients and insurers will spend money yet find nothing. This is not an affordable, sustainable undertaking. It’s like a complete physical on an asymptomatic patient. You spend money to find something, but the exam is normal. The outcome at that moment is negative, but to find a cancer you need to look again in the future. It’s a “cost-benefit” nightmare.
What needs to be developed is free cancer screenings for asymptomatic patients, along the lines of the vascular ultrasound screenings by “Life Line Screening.” Technology needs to be developed that can detect cancers in asymptomatic patients. In “Star Trek,” Dr. McCoy merely put his patients in a scanning device, and their diagnosis was known immediately. Of course, that device was fictitious and the product of imaginative, futuristic writers. Today’s CT, MR, and PET technologies are not far from that employed by Dr. McCoy, but they are not 100% accurate nor are they as sensitive as needed. Unless I’m unaware of it, nothing of this nature yet exists to find the 86% of cancers currently-available screenings don’t detect. To expect such technology will exist in the future is unrealistic; but then so much of today’s technologies were only dreams 25 years ago, such a device may yet be invented.
While it is disheartening to learn that less the 15% of all cancers are discovered via screening procedures, medical practitioners should continue to recommend and use the screening techniques currently available, while continuing to do research into new methods of detection. I think it’s a real possibility such technology will be discovered. Then, doctors can significantly improve cancer detection rates and cancer deaths will finally decline.
References: https://www.cnn.com/2022/09/28/health/cancer-screenings-prwen-wellness
