Struck out with metformin prescription

Melg-
I doubt that Metformin hurts - there is certainly no evidence that it's harmful. It may be helpful, but until we have results of randomized clinical trials, we really have no idea. Anytime we take an unproven medication or supplement we are taking a risk that it may be innocuous at best or harmful at worst. Look at Vitamin E. Look at recent evidence that antioxidants may subvert our natural cancer control mechanisms. Cancer cell survival pathways are incredibly complex, and it is often the case that blocking one pathway augments another. My gut feeling - and it's just a feeling, with little proof - is that to make any progress against prostate cancer, it will prove necessary to block multiple survival pathways and perhaps work on tissue-based effects simultaneously.

If I were in that situation, the 3 medications I would ask my doctor if I could take would be low-doses of aspirin, statins and metformin. Probably I'd take a sulforaphane supplement too. But my principal reason would be to get a feeling of control, even while acknowledging that it probably has no effect. I think it's important to give oneself that psychological benefit, possibly it can even help the immune system.

I didn't understand your statement: "that didn't make sense with what they thought was gleason 6 and clean pathology. Now we are regretting not pushing that as it appears to have been gleason 7 and it may have helped." The pathology report was one or the other - Gleason 6 or Gleason 7, no?

In GETUG-AFU 16, all the men were Gleason 7-10 at pathology and had rising PSA. This study was just announced at the ASCO meeting in June, and the official results have not yet been published in a peer-reviewed journal. I'd predict that there was less benefit, if any, among the lower-end Gleason scores, especially if they were GS 3+4.

- Allen

You may not have too much longer to wait. The PROTECT trial on Provenge early use completed in April and the ProstVac/Tricom/Xtandi early use trial wraps up next year. Although the ProstVac trial is a preliminary Phase 2 trial, if it shows efficacy, they may recruit for a Phase 3 trial that he could get in on.

- Allen

the Provenge data gets reviewed, and the FDA has to determine whether the new use is warranted. Usually takes less time than a new drug.

I'm talking about hormone sensitive, non-metastatic for Prostvac here. No Phase 3 trials yet that I know of for that use.

Xtandi is still only approved for metastatic, castrate-resistant PC. Doctors can prescribe any approved drug off-label, but it is totally up to the insurance company whether they will cover an off-label use, and they usually won't for an expensive drug.

- Allen

They are both only approved for metastatic, castrate resistant. One can always try to get approval for an off label use. Sometimes they'll approve it, sometimes not, sometimes on appeal. It is automatically covered by a clinical trial.

- Allen

Mel,
My reply was: you can try to get one of the advanced hormonals.

If one isn't already on Casodex, the Onc may try re-challenging with it; if one is already on Casodex, the Onc may try taking it off. Keto and estrogen patches will often get approved.

I think most insurance would allow LNs larger than 1 cm, but you should check first.

- Allen

Allen
As evidence that I'm not just looking to justify metformin use, I found this article that points out time bias as one of the reasons that metformin studies at times show great illusory results.
http://m.care.diabetesjournals.org/content/35/12/2665.short

In summary, "These studies, subject to time-related biases that are avoidable with proper study design and data analysis, led to illusory extraordinarily significant effects, with reductions in cancer risk with metformin ranging from 20 to 94%. Three studies that avoided these biases reported no effect of metformin use on cancer incidence."

In spite of that, I'd be willing to try low dose metformin, 500mg/day,
as one of my friends is doing with his doctor's approval. However, you've given me second thoughts with your comment that metformin use, though probably safe, may cause cancer cells to develop alternate survival mechanisms .

Along with interest in metformin, I've adopted diet and exercise, so far losing 20+ pounds in 3 months. Please don't tell me that the efficacy of diet and exercise also needs to be confirmed by controlled studies :)