Another young female presents in my clinic with a newly diagnosed thyroid cancer and has been recommended urgent thyroidectomy. Her story is increasingly common. If you’re not seeing it in your clinic, you will, because thyroid cancer, and almost exclusively papillary thyroid carcinoma (the form my patient and most young patients have), is dramatically increasing. Since the 1970s there has been a 67% increase in the incidence in women and a 48% increase in men documented in 5 continents (Peterson et al 2012). Australia, though less up to date with its data collection, found a similar increase between 1982-1997 (Burgess 2002). The question begging to be answered is why.
Increased screening and more effective detection of smaller tumours was the going theory for years. New research rejects this absolutely and concludes instead this is a ‘true increase in occurrence’. Increased radiation exposure? Mutation studies say no. Many researchers are pointing to is a ‘new environmental chemical and/or dietary factor’ and EDCs (Endocrine Disrupting Chemicals) that target the thyroid such as perchlorates, phthalates, parabens and phenols are the likely suspects. And, more than likely, with iodine deficiency to explain the increased susceptibility to these EDCs.
But wait there’s more. These ‘new goitrogens’ aren’t only implicated in thyroid cancer, a large number of human studies confirm the higher your urinary metabolites of these, the lower your thyroid function. More worryingly is that they might be doing this ‘without a trace’. With myriad impacts at the receptor level, altered hormone excretion rates, impaired peripheral conversion etc. the data to date suggest these patients TFT results might only look ‘slightly low’ or even ‘normal’ but the reality is they are suffering hypothyroidism. Sound familiar?
There is a HUGE body of scientific evidence we can pull from to understand the role of EDCs in thyroid problems in our patients, how to maximise prevention and minimise impact – even when your patient, like mine, is perhaps already in the full grip of the consequences. I’ve read all the papers and summarised them in this 30min recording: Hypothyroid without a trace – the role of EDCs.