Having just returned from the Endocrine Society Conference in a snowy Boston, I came away still to be convinced that molecular testing for thyroid cancer has lived up to it's promise.

Molecular testing helps give additional information about what genetic errors a thyroid cancer has acquired. Some of these errors are associated with more aggressive tumour behaviour, but quite how that helps make treatment decisions is still a bit unclear.

Here's a useful discussion involving some key leaders in the field (always worth listening to what Dr Tuttle has to say on thyroid cancer).

In the hospital I work in (in New Zealand) we have decided not to include molecular testing. Instead we are going to wait until we can be convinced that such testing will result in better patient outcomes before we add it to what we do. However, we'll be watching this space with keen interest in the hope that it will soon offer clear benefits to patient care.

Medullary thyroid cancer is one of the rarer forms of thyroid cancer, but unlike most other thyroid cancers, it doesn't take up radioiodine. This means that one of the key weapons we often use to attack thyroid cancer is useless against medullary thyroid tumours.

The search for new drugs that can target medullary thyroid cancer is on-going.

Here's a new approach that is coming to light. It's a long way off being ready for use, but it's encouraging to see progress, particularly using an approach that is a bit different.

Some of the current drugs target some of the biochemical machinery inside the cells, whereas this approach aims to attach a radioactive molecule to something that sticks to or gets taken up by the medullary thyroid cancer cell.

​Whilst it's perhaps unlikely that any drug will be 100% effective, having a range of different drugs or different strategies might work well together.

There has been recent news about the risk of a second cancer some years down the track, after having had radioiodine treatment for thyroid cancer.

This recent study  has caused some headlines, and understandable chatter around the thyroid cancer community, including on the THYCA facebook page.

Should we worry?  

No

Should we use this information to help guide whom to treat with radioiodine?

Absolutely.

Does this change what we should be doing?

Not really. I say this because such data is already well known, and is already factored in to many of the best guidelines (such as the American Thyroid Association guidelines). Given the known small risk of death from second cancers (approx 1% lifetime risk) caused by radioiodine (particularly the higher doses of radioiodine), we have to be fairly sure that the radioiodine is resulting in a higher chance of benefit than harm. That is partly why we don't generally recommend radioiodine for those patients with low risk thyroid cancer.

I've also seen questions about whether screening for these second cancers might be a good idea. This raises the issue of how best to screen for such cancers. You have to be careful not to be causing either excessive psychological harm (repeated screening that has low yield can cause psychological harm such as anxiety) or physical harm (radiation from repeated CT scans can also cause cancer - here's an example from the world of adrenal incidentalomas - in a nutshell each CT of the abdomen has about a 1 in 3000 risk of causing death from the associated radiation).

So in summary - yes it's great to have new research than helps inform what the best treatment should be, but his particular study should not cause alarm. Instead it should provide further confidence that clever people (not me!) are continually trying to find the best possible treatments for thyroid cancer and that the move towards giving lower doses of radioiodine and only treating those thyroid cancers at higher risk of causing future ill health is a sound way forward.

Interesting stuff - finding the balance between not missing important thyroid cancers, and not over-diagnosing thyroid cancers that are not likely to cause any ill-health, remains a challenge. Looks like Korea is moving towards a more conservative approach, more in line with the more typical international approach. Seems sensible to me.

I liked this story - a TV host in the US received a message from a concerned viewer, suggesting he get his visible thyroid nodule checked out. It turns out to be thyroid cancer, from which he is now doing well.

​Thyroid cancer diagnosis, from your armchair!

As a proud New Zealander, I couldn't help try to get in a tenuous mention of the All Blacks' recent win at the rugby World Cup.

What has the All Blacks captain Richie McCaw, and other star players like Dan Carter have to do with thyroid cancer?

Well, in the afterglow of their impressive world cup campaign, they will no doubt deserve a beer or two.

​A recent study has shown that the risk of developing thyroid cancer does not seem to be associated with any particular dietary factors. However, there was an associated between lower risk of thyroid cancer and a higher level of alcohol consumption!

Whilst such a study does not prove causality (i.e. it may link higher alcohol intake with lower thyroid cancer risk, but doesn't prove that one leads to the other - it may be an associated factor rather than the alcohol itself), it does perhaps provide some comfort for those who have one beer more than they should!

Hats off to those investigators that continue to try to improve treatment of those people with thyroid cancer that is no longer responding to standard treatment or surgery and radioiodine.

Recent reports of trials of Pazopanib and Lenvatinib clearly show that the search for effective new treatments for progressive thyroid cancer is continuing at pace, but the results remain a fair bit short of what we are all hoping for. That said, progress in the cancer world is often made in little steps, and as long as you don't stop, even someone taking little steps will eventually reach their destination.
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The new American Thyroid Association guidelines suggesting how to manage thyroid nodules and differentiated thyroid cancer have just been published. They are long-awaited, and welcome.

At over 400 pages long, and citing more than 1000 references, its a huge piece of work. Despite its size and weight, the guidelines have kept a strong common-sense feel, with many of the recommendations advocating a more conservative approach than in the past, reflecting that many thyroid cancers have a relatively favourable prognosis.

I particularly like the emphasis on re-staging people, based on how their disease does (or doesn't) progress with time. This allows the vast majority of patients (who are going to do very well) to have a more relaxed TSH target, and to hopefully help them to move through and beyond their thyroid cancer experience.

Well done the ATA!

The question of whether the Fukushima nuclear power plant tsunami disaster has or will cause more cases of thyroid cancer remains unanswered, but a recent report may be evidence of a small tide of such cancers. 
Its now getting coverage in the mainstream press .
The report looks far from conclusive as yet, with issues such as timing (perhaps cases appearing a bit earlier than expected after the exposure to radioactivity), and the lack of data on what exposure the patients had to radioactivity, but its the first signs of a potential effect.

If you'd like to know how to fight thyroid cancer like a girl, have a look here.
Great stuff.