Does ADT actually kill cancer cells?

It's probably more complicated that I understand, but I think of ADT as something that prevents prostate cancer cells from multiplying by depriving them of testosterone. Perhaps that sometimes keeps their clusters small enough that your immune system can successfully attack them (???), but I don't see how ADT could kill cancer directly.

Radiation and chemotherapy definitely do kill cancer cells.

I don't believe it kills cancer cells. It reduces testosterone.

The way my RO described it was like this.

The ADT denies the cancer cells the food they need to survive, testosterone, thereby weakening them and preventing them from multiplying

The radiation damages the cancer cells by changing their DNA so that they can't replicate and die off.

This may have been an oversimplification for the purpose of explaining it to an idiot such as myself.....LOL

Your explanation was awesome as I m on ADT for 18 months now.

ddl, this isn't an answer, but:
with some equivocol areas of low SUV (standard uptake value) advice was to take orgovyx for two months and repeat the PSMA/PET.
If the questionable areas had the same SUV we'd know that it wasn't cancer.
If those areas had a lessened or no SUV, we'd know that it was cancer. Which suggests that ADT can obscure the testing of cancers in the prostate and those that had metastasized. ADT deprives the cells of the testosterone they need to grow. But the tumors had shrunken-- one to half it's size, which might suggest that some of the cells had died.
I really like your question and hope someone answers who knows.
Can hibernating cells migrate. That would make taking ADT a possible hinderance for detection and treatment.

to reinforce what @web265 says

ADT doesn't kill prostate cancer cells, but it can weaken them and slow their growth.
ADT works by blocking androgens, male hormones that prostate cancer cells need to grow and spread. This can put the cancer cells into a dormant state, making radiation therapy more effective.

ADT is often used in combination with radiation therapy for locally advanced prostate cancer.

However, ADT is rarely curative, and some prostate cancer cells can develop the ability to grow in the low-testosterone environment created by hormone therapy. This state is called castration-resistant prostate cancer (CRPC), and hormone therapies have less and less effect on tumor growth over time. Recent clinical trials have shown that combining ADT with other agents, such as docetaxel and abiraterone, can lead to improved survival

There is frequently no "best" decision. In treating cancer there are trade-offs between present discomfort, the projected course of the untreated disease, and for every proposed treatment: duration of treatment, possible outcomes, expected outcome, immediate side effects, and long term side effects (e.g. cognitive difficulties, lymphedema, heart disease, peripheral neuropathy, secondary malignancies, etc.) Learn all you can about these many factors and then make a "good" decision.

Why combination therapy - heterogeneity and evolvability, via genetic or nongenetic mechanisms, are two of the greatest obstacles to the successful treatment of cancers.

I'm about to undergo 2 treatments using hdr/brachytherepy. My oncologist likes the prospects.

This was my understanding as well. Which begs the question, why stay on ADT for 19 months post radiation? I could understand an additional 4-6 months, allowing time for the radiation to complete its task. Staying on ADT more than that seems like it’s either useless, because you’re already cured, or simply postponing the inevitable recurrence while possible making your cancer hormone resistant.

I am sure there is a trial that came to the conclusion of the various time intervals that doctors prescribe for ADT. For me, I was a classic biochemical recurrence and we went with a 24-month period.

In terms of does ADT kill cancer, the way my team talks with me is that ADT is starving the cancer cells of what it needs to grow. All cells in our body that are alive are trying to divide and keep going. That is why our finger nails and hair grow (visually you can see this) but inside the body the same things are happening. ADT robs the prostate cancer of the fuel it needs, but like your own body, you could fast for 1-day, 2-days, heck you could skip food for a month and you'd still be alive (all you need is water and air). So to truly starve the cancer, you need a healthy amount of time to put that in action. Think of yourself, you could probably go without food for months and enter into starvation mode and your body would be weak very much so. But if you then started to eat food and nutrition, you likely would recover. same goes for the cancer, ADT is trying to starve every last cell until they can't go any further. Hope this makes sense. KTF

I think the original question, "Do hormones kill prostate cancer cells" deserves more clinical research. I suspect the difficulty lies in how do you measure the quantity of cancer cells before and after hormone treatment. I have had three urologists treat my prostate cancer. When I asked the question about hormones killing cancer cells, two replied no, they don't, and one confirmed hormones did kill prostate cancer cells. Okay, now what?
I know the book answer is hormones only suspend the growth of cancer cells, keeping them inactive (preferably forever). But I want to share a short statement on the subject that I found on a Mayo Clinic site. It reads: "Most prostate cancer cells rely on testosterone to grow. Hormone therapy causes prostate cancer cells to die or to grow more slowly". Interesting.
If anyone wants to type in all these characters, they can read it themselves. http://www.mayoclinic.org/tests-procedures/hormone-therapy-for-prostate-cancer/about/pac-20384737
That's all there is. I personally hope hormones do whittle down the prostate cancer cells.