It’s time to address the overtreatment of thyroid cancer
In 1994, my entire thyroid was removed because of a single, small tumour. Then I was dosed with radioactive iodine. Aggressive treatment for my kind of cancer has been standard for decades.
But earlier this year, an international panel of experts called for a paradigm shift in thyroid cancer diagnosis, in order to spare many thousands of people, like me, the unnecessary loss of a vital organ. A certain type of non-invasive nodule, accounting for about 20% of all thyroid cancers, will no longer be labelled carcinoma if the recommendation is heeded.
Led by Dr. Yuri Nikiforov, a thyroid pathologist from the University of Pittsburgh, the group published a study in the April issue of Jama Oncology providing the rationale for a name change. The tumour in question is a variant of the common papillary cancer that is confined within a capsule. The study followed 109 patients with such tumours for between 10 and 26 years. None had a recurrence of disease even though 69 had only a partial thyroidectomy.
While the study population was small, the length of follow up offers convincing evidence of the innocence of these type of lesions. The panelists decided they now should be labelled “non-invasive follicular thyroid neoplasm with papillary-like nuclear features,” or NIFT-P. They reason that patients will be less anxious about a non-cancer diagnosis and doctors less zealous about treating something called a neoplasm instead of carcinoma.
The terminology sounded familiar. I dug out my pathology report. Sure enough, I had an encapsulated nodule, labelled a “follicular variant of papillary carcinoma.” It seems I had NIFT-P. Not cancer.
When I was diagnosed, doctors already knew that this kind of tumour, once removed, was rarely a threat. Yet, to be on the safe side, they removed the entire gland. And to kill any lingering thyroid cells left behind, they asked patients to swallow radioactive iodine. I was isolated in a hospital room for three days, so radioactive, that no one could come near me.
Fortunately, I did not suffer any possible side effects, such as mouth dryness or damage to vocal chords. Without a thyroid, however, I was now consigned to thyroid hormone replacement pills for the rest of my life. My body wouldn’t survive without it. For extra insurance against cancer coming back, the dose was high. I was on that high dose for 20 years, not knowing it was making me anxious and inexplicably emotional at times. Nor did I know that prolonged high doses are associated with heart arrhythmia.
I sent my pathology results to Dr. Nikiforov who said without seeing the actual tissue, he couldn’t be 100% sure, but agreed I most likely had NIFT-P. For patients like me today, he advocates removing only the section of thyroid containing the nodule. With half a thyroid still intact, hormone replacement is often not necessary.
The Jama Oncology article, and an accompanying editorial, both suggest that overtreatment of these particular tumours, with complete thyroidectomy followed by radioactive iodine, is still common practice in North America and Europe. Nikiforov estimates that the new paradigm will affect 45,000 patients worldwide each year.
Canadian data support his argument. In an analysis of Ontario statistics, Stephen Hall, an ear, nose and throat surgeon at Queen’s University in Kingston, found that between 2000 and 2008, the incidence of thyroid cancer doubled, largely due to an increase in ultrasound detection of small, impalpable tumours that caused no symptoms. As the numbers increased, so did the number of total thyroidectomies. Complete removal, as opposed to a partial removal of the thyroid was done in 62.4% of all cases, varying across regions in Ontario from 29% to 82%. Additional treatment with radioactive iodine was given to two thirds of those patients.
Hall has looked at more recent, as yet unpublished, data in Ontario and observes that, as in the rest of the world, the rates of thyroid cancer continue to rise due to overuse of diagnostic tests. Rates of total thyroidectomy also continue to increase, though the use of radioactive iodine is levelling off. He thinks new labelling of some these cancers could be a game changer in managing not just NIFT-P, but other low risk thyroid cancers too.
In a recent statement, Toronto’s University Hospital Network/Princess Margaret Endocrine Site Group, also endorses a more conservative approach. Dr. James Brierley, radiation oncologist, and head of the group, says that in his centre, removing half of the thyroid without radioactive iodine is standard for non-invasive tumours, and he’s keen to get the message out that “people with early stage thyroid cancer, or now, not even thyroid cancer, don’t need to be aggressively treated.”
The truth is, the vast majority of thyroid cancers are highly curable, even when metastatic. Many are indolent and left alone would cause no harm. A one-size-fits-all aggressive treatment, rooted in a simplistic “war on cancer” is outdated and harmful. Just as prostate and breast cancer have been overdiagnosed and overtreated, so has thyroid cancer, at the cost of unnecessary morbidity.
The promise of a paradigm shift, through a name change, is welcome news if indeed pathologists embrace the recommended criteria for identifying NIFT-P. Other low-risk thyroid cancers also need to be identified, and the regional differences in thyroid cancer management must be addressed. I can’t get my thyroid back, but others can be spared unnecessary treatment.
Renée Pellerin is a former CBC health journalist currently working on a book about the history and politics of breast cancer screening.