Common Thyroid Tumor Downgraded to Non-Cancerous
In a move that will change the lives of tens of thousands of people around the world, an international panel of pathologists and clinicians has decided to rename a type of thyroid tumor—until now deemed malignant—as non-cancerous, thus sparing patients a variety of aggressive treatments and side effects as well as a cancer diagnosis. The panel published the data supporting their decision in the April 14, 2016 edition of JAMA Oncology.1
“This decision confers enormous medical and psychological benefits for patients,” said Yuri Nikiforov, M.D., chairman of the panel and professor of pathology at the University of Pittsburgh. “Now patients do not need to undergo complete thyroidectomy, do not need radioactive iodine therapy, do not need to be checked every six months for the rest of their lives and will not be labeled with cancer.”
Although the tumor in question—Encapsulated Follicular Variant of Papillary Thyroid Carcinoma, known as EFVPTC—has long been considered extremely low risk, it is typically treated as conventional thyroid cancer, largely because of the word carcinoma.
“The word ‘cancer’ implies that there is a high likelihood the tumor will spread to local lymph nodes or distant sites and cause significant harm or death,” said R. Michael Tuttle, M.D., a panel member and clinical director of endocrine services at Memorial Sloan Kettering Cancer Center. “Tumors like these don’t meet any of those criteria and therefore calling them cancer leads to undue worry and often excessive treatments.”
By reclassifying the tumor as non-cancerous—a decision made after the panel put its risk of spreading or causing harm at less than 1%—patients will no longer have to undergo radioactive iodine therapy, which can damage the salivary glands, cause pain and increase the risk of secondary cancers; or take thyroid suppression hormones, which have been shown to increase the risk of osteoporosis and heart problems.
While some news reports, including The New York Times,2 have suggested that people diagnosed with the condition will no longer require surgery, Dr. Tuttle was quick to point out that is incorrect. “The reclassification gets patients out of everything downstream of surgery, but not surgery itself,” he said. Although patients now may well be spared complete thyroidectomy, a lobectomy—in which half the thyroid is removed—is still required to rule out the tumor’s possible invasion of the capsule that contains it as well as blood vessels nearby. 3
Another possible benefit of the renaming: While patients who undergo complete thyroidectomy have to take thyroid hormone pills for life, many of those treated with lobectomy won’t need the pills at all. 3
The tumor, sometimes referred to as a nodule or lesion, has been renamed NIFTP, for Noninvasive Follicular Thyroid Neoplasm with Papillary-Like Nuclear Features. It is by definition non-invasive, but that determination cannot be made until the tumor and the so-called capsule surrounding it have been removed during a lobectomy (the tumor alone cannot be easily or safely excised), and then carefully inspected by a pathologist. “The important thing is that the entire capsule be looked at—however many slides that takes,” Dr. Tuttle said. 1, 3
The panel, which included 24 thyroid pathologists from 7 countries and 4 continents, moved to rename the tumor after finding that none of the 109 patients in its study diagnosed with noninvasive EFVPTC suffered a recurrence or other manifestation of the disease at a median follow-up of 13 years. That was not the case for patients who had been diagnosed with the invasive form of the tumor. 1
“This is a bold move and overall a good thing,” said Bryan Haugen, M.D., professor of medicine and pathology and head of the division of endocrinology, metabolism and diabetes at the University of Colorado School of Medicine, noting that the decision falls in line with the 2015 guidelines issued by the American Thyroid Association and published in Thyroid. “We don’t need to be so aggressive in treating something that’s not behaving like cancer. And if it’s not behaving like cancer, why call it cancer?” 4, 5
The incidence of EFVPTC has risen two-to threefold over the past 20-30 years and makes up 10-20% of all thyroid tumors diagnosed in Europe and North America, according to the report released by the panel. The increase is usually explained by improvements in diagnosis. The panel said that the decision to reclassify the tumor will affect more than 45,000 patients every year worldwide. 1