Hormone holiday thoughts

I've come across a number of men on Intermittent Hormone Therapy (IHT). It's suitable for men on lifelong hormone therapy whose PSA has stayed very low, and only rises slowly when exposed to Testosterone. The original trials showed that in this cohort of suitable men, it didn't significantly shorten life, but gave a better QoL.

If you are on any of the ARPI's (Abiraterone, Enzalutamide, Apalutamide, Darolutamide), there's a problem that once you stop, you won't be able to restart them again (NHS rules won't fund them again), so that's going to be a factor for some people to consider.

I talked with an Oncologist about it a few years ago, and he said his IHT patients spend longer off HT than on, although that predates Relugolix so some significant proportion of the 'off' time with have been waiting for recovery of Testosterone. More recently, I've seen men switching to IHT have been switched to Relugolix, because the Testosterone recovery time is faster.

Usually the way it works is once you've had a very low PSA for a couple of years, you would be considered for IHT (although you usually have to ask rather than it being proactive on their part). Then you agree an upper limit on your PSA with your oncologist which might be something like 5, 10, or 20 (depending on your age and what your original PSA was), and then you stay off the HT until you reach that level, and then you go back on. You then stay on until your PSA has become very low again for some period such as 6 months.

There was originally some thought this would prevent or at least push out the point where you became castrate resistant. That wasn't seen, but it didn't bring it forward either. In terms of how long men lived on IHT as opposed to full HT, it was only very slightly shorter but the quality of life was significantly improved.

IHT is not the same as Bipolar Androgen Therapy (BAT), where you are more quickly cycled between high and castrate levels of Testosterone. This switching is done more quickly than your body can recover Testosterone naturally, so you stay on hormone therapy all the time, but have Testosterone injections to create the recovery periods. The idea here was to prevent becoming castrate resistant, or even reverse it. The only person I've heard of in the UK who tried BAT was on this forum and convinced his oncologist to let him try it, but sadly died during the first Testosterone boost when his cancer went rampant. It was very late in the day when he tried it though.

The support and advice on this forum never fails to amaze me. Thank you all.

It’s reassuring to hear this is a reasonably well‑trodden treatment option, at least in certain cases. Barry and Dave, I agree this needs a discussion with my oncologist, although I’m increasingly comfortable proceeding even if they’re not entirely on board, provided the evidence supports it. I’ve disagreed with my onco before after excellent advice here and a second opinion from the Royal Marsden on metastasis‑directed RT which has so far delivered good results. That said, I value their input hugely and we have a strong relationship.

Dave, I know my team would be open to discussing approaches like intermittent hormone therapy, but I agree it wouldn’t be initiated by them, I’d need to make the case. As with my self‑funded PSMA PETs and RT to all tumour burden, there seems to be a level of self‑advocacy required that I haven’t seen elsewhere in the health system. I’m not sure whether that’s locality‑specific.

Jules, I imagine the Prostap break would be for as long as is safe, whatever that turns out to be. I’m not sure how long people typically stay off ADT before PSA rises. My concern is the long‑term effects: bone health is fine for now, but cholesterol has crept up, and I know there are thyroid and diabetes risks too. The fatigue is a challenge but equally if I were told I had to deal with it I would. I’d be comfortable with monthly PSA checks if recommended, the GP surgery is on my route to work. I try, where possible, to make this disease fit around my life rather than the other way round, probably a control thing.

Thanks Adrian for your kind words and for the video link, I’ll watch it with my wife. I’ve found Dr Scholz’s videos extremely helpful in past treatment decisions.

Crispin, I’m currently on Prostap only. Bicalutamide was used briefly at diagnosis to put the brakes on. I was offered a second‑generation hormone post chemo/radiotherapy, but we agreed to keep it in reserve. I know some advocate adding Enza or Abi alongside Prostap, and I think I’d be eligible. I hope you reach a decision on Decapeptyl. I completely understand why oncos in England, Germany, or France would worry about fuelling micromet growth, even with a low PSA. For us as patients, getting as close as possible to normal quality of life, reducing medication where safely possible, and carefully balancing risk while avoiding spread feels like the dream scenario.

Andy, thanks, perhaps 10 months of low PSA isn’t considered long enough. Relugolix is interesting; I wasn’t aware it could speed testosterone recovery. Agree that defining an upper PSA limit with my onco would be essential. Any rise would horrify me, but I’d have to get past that if I pursue this route. My presenting PSA was 31, and I’m 46 years old. The fact that this approach doesn’t seem to impact overall survival is probably why it appeals to me.

Well Onco phone call next week, will update on progress with this. Thanks again all.