Castration by Estrogen Patch

[janebob99]

This plot shows a dramatic decrease in testosterone and PSA after starting estrogen patch therapy, indicating that transdermal estrogen (TDE) therapy effectively castrates men, and with fewer side effects than Lupron ADT.

[Tony666]

I wonder if it brings it as low as ADT. That would be the right comparison. Because your chart says that you still have 10%, which if you have 400, say, testosterone that would still leave you with 40 after estrogen therapy which might not be low enough to starve the cancer cells. I think most ADT brings it lower than 40.

[janebob99 in reply to Tony666]

You raise a good point.

So, I converted the scale to standard T units (ng/dL). The vertical axis now ranges up to 500 ng/dL. You are right that the nadir is about 10% of the maximum (starting) value in this individual. So, 10% of 500 is 50, which equals the green dashed line that I drew. (The actual lowest point (nadir) on this graph is 38 ng/dL). It is generally accepted that a testosterone level below 50 ng/dL is equivalent to castration. So, this individual was "castrated" by the estrogen patch therapy. Of course, lower is generally better in this low-testosterone / castration regime.

Now, this is data for an individual. So, for a group of men, there will be a distribution of nadir levels around a median value. We just don't have that sort of data available. Some men's nadir will be lower than 38 and some will be more than 38. Plus, the nadir level is probably a function of how many estrogen patches are used every day.

Thanks for your question/obseravation !

Bob

Estrogen Patch Therapy

[London441 in reply to janebob99]

38 isn’t low enough for me, ever.

[janebob99]

I'm curious, how do you know that 38 is too high? How low do you go, and what effects do you notice? PSA changes?

The nadir with estrogen therapy is likely dependent on the E2 dose, which could be easily titrated to get whatever level of castration that is needed. Just a thought...