When it comes to treating cancer, we’ve made some pretty amazing advancements in recent years: Not only has technology advanced to better treat cancer at any stage, we have some of the most advanced screening methods that can pinpoint even the smallest of tumors. But is our screening and subsequent treatment process negatively impacting those with less severe forms of cancer? Some doctors are starting to think so.
When doctors reference overdiagnosis, they often use thyroid cancer as a primary example. According to the National Cancer Institute (NCI), cases of thyroid cancer have been growing at an alarming rate: In 1992, only 5.9 per every 100,000 Americans had been diagnosed with thyroid cancer compared to 14.9 in 2012. This rate is two and a half times higher than it was just 20 years ago, the NCI said. However, the rate of people who have died of thyroid cancer has not changed since 1992. In fact, it’s actually remained the same since 1935. So why are we hearing of more cases popping up now?
According to a recent study published in the journal Thyroid, this increase can only be attributed to improved screening methods, not an increased incidence of cancer. Thanks to modern MRIs, CT scans, and ultrasound-guided biopsies, doctors are able to find any type of tumor, regardless of the size, better than ever before. But, the study found that these tumors may cause unnecessary alarm — in fact, the smaller ones are often not life-threatening at all. Some people can go without treatment and not experience a single symptom.
Yet, the screening process compels both doctors and patients to act, which can lead to unnecessary surgeries that can potentially cause health risks more dangerous than the actual tumor. “There is absolutely no evidence that screening for thyroid cancer provides any benefit to the patients,” lead study author Dr. Juan Brito Campana, an endocrinologist for the Mayo Clinic, told The Huffington Post.
Surgically removing the thyroid (thyroidectomies) can be costly, both financially and physically. The researchers found that on average, Americans spend a total of $1.6 billion each year on treating thyroid cancer, with diagnosed patients being 2.5 times more likely to file for bankruptcy. Not to mention patients who have a thyroidectomy have to take replacement hormones for the rest of their life, which could also lead to complications; plus, surgeries in sensitive areas like the throat often come with risks.
That said, it’s not just thyroid cancer that’s overdiagnosed. Early detection may be essential in treating more aggressive cancers, but when it comes to more slow-growing forms, some doctors say we must take another approach. For example, many experts are starting to speak out against ovarian cancer screenings if women don’t otherwise indicate development of the disease.
“Each individual person who is a missed diagnosis is a tragedy,” Dr. Robin Fiore, a bioethicist of the University of Miami, told HuffPo. “But every individual person who has unnecessary surgery is a tragedy as well. And in some types of cancer, there are more of the latter than the former.”
Those opposed still believe screening is necessary, finding that the benefits are equal to the risks. Dr. Therese Bevers, a professor of clinical cancer prevention at Anderson Hospital in Houston, believes that we should focus more on the harms of over-screening, rather than getting rid of screening altogether.
“My concern is that we’re throwing the baby out with the bathwater,” she said. “Screening isn’t a bad thing as long as we aren’t treating thing that don’t need to be treated.”
To try and come up with a new approach to cancer screening, doctors are looking toward recent changes made in the process of detecting prostate cancer. In the early ‘90s, doctors commonly tested men over the age of 40 for a biomarker of the cancer, called the prostate-specific antigen (PSA). As a result, rates of prostate cancer skyrocketed, and doctors moved to treat all the new cases with more doses of radiation and prostate removal srugery, respectively. But overall, prostate cancer is often not a life-threatening illness. In fact, most tumors progress so slowly that men will often die of other causes without even knowing they had one.
Once it became apparent that prostate cancer treatment was doing more harm than good, the U.S. Preventive Service Task Force told doctors in 2012 that they should stop screening men for PSA. Since then, rates of prostate cancer diagnosis have slightly decreased.
Many doctors are now electing to adapt the “active surveillance” method in light of these recommendations. For example, Dr. Ashutosh Tewari, the chairman of urology at Mount Sinai Health System in New York, says that the tools used to screen for cancer can also be used to monitor the progression of the cancer with “stunning accuracy,” allowing doctors to see if treatment would be necessary.
“In patients on surveillance, we do frequent imaging and genomic analysis on biopsies of the prostate, which can tell us if the cancer is low risk or high risk,” he said. “And we’ve found that in between 50 and 70 percent of patients, the cancer remains indolent.”
As a result, more men are receiving treatment only when they need it. And though many still debate whether the current screening process is going a bit overboard, it seems that vigilant surveillance may be the best best. Treatment might not be necessary, but at least doctors will know if it becomes necessary down the line.
Source: Brito J, Montori V, Hay ID, et al. The Impact of Subclinical Disease and Mechanism of Detection on the Rise in Thyroid Cancer Incidence: A Population-Based Study in Olmsted County, Minnesota During 1935 Through 2012. Thyroid. 2015.