ADT use may have an immunological benefit during the pandemic

The CDC recommends Covid-19 testing for cancer patients who may be immune-compromised by their cancer or chemo treatment.The extra caution is justified only in men with late-stage PC. Those who have already had prostate radiation, may have some immune enhancement, perhaps especially with SBRT (pre-clinical). The exception may be those who have had whole-pelvic radiation. Assuming that Covid-19 (unlike Spanish Flu) is milder in those with better immune systems, it is possible that ADT may improve their immune response to the disease.

Data are showing that men are dying of Covid-19 at greater rates than women. This may be because of genetic effects and hormonal effects. Testosterone was found to be immunosuppressive for influenza.  ADT has been found to be immunoprotective (here and here).

Early Covid-19 data are confirming this (here and here)

While normal levels of estrogen seem to be immunoprotective, high levels, as in pregnant women or men on Bipolar Androgen Therapy (because testosterone is metabolized to estradiol), reverses the protection. The implications for ADT use are:

• If you are on continuous ADT, stay on it. This is true even if ADT has been augmented with Zytiga and prednisone, or anti-androgens.Those taking Zytiga with prednisone needn't worry because the prednisone is only a replacement dose, and is not large enough to be immunosupressant. Because of negative feedback, it is more dangerous to take too little prednisone. 
• If you are on intermittent ADT, this might be a good time to end your ADT vacation. 
• Men using Bipolar Androgen Therapy on a clinical trial should discuss the timing with the trial investigator. Anyone taking supraphysiologic doses of testosterone should consider this as well. 
• If you are taking adjuvant ADT after radiation, or neoadjuvant ADT before radiation consider sticking with it a little longer.

(Update 9/23/21) A very small sample size retrospective study found there was no statistically significant difference in Covid-19 death or severity between men who used ADT for PCa  (11 men) and men with PCa and Covid-19 who did not use ADT (80 men).

Also see the recommendations for those getting radiation therapy.

Radiation in the Time of Covid-19

A panel of top radiation oncologists in the US and UK addressed the question of putting off or shortening various kinds of radiation treatments for prostate cancer at a time when it is best to maintain distance from institutions that treat patients.

Their recommendations depended on the disease setting. For detailed recommendations, see this table. They recommend:

• Consultations and return visits post-RT should be handled by telephone or online if possible.
• The preferred therapy for all favorable risk prostate cancers (very low, low, favorable intermediate risk) is active surveillance during the pandemic.
• 4-6 month depot injections of a GnRH agonist (e.g., Lupron, Eligard, Zoladex, etc.) should be used prior to primary RT for all unfavorable-risk patients (unfavorable intermediate risk, high risk, and lymph node positive). If there must be treatment during the pandemic, a shortened course of external beam RT using moderate (20 treatments) or extreme hypofractionation (5 treatments) is recommended.
• Brachytherapy should be avoided during the pandemic, and delayed until afterwards if desired,  due to high exposure of anesthesiological medical staff.
• Adjuvant/Salvage RT should be delayed. 4-6 month depot injections of a GnRH agonist (e.g., Lupron, Eligard, Zoladex, etc.) may be used during the delay.
• De-bulking the prostate with RT in patients with low volume metastases can be delayed with 4-6 month depot injections of a GnRH agonist (e.g., Lupron, Eligard, Zoladex, etc.).
• Treatment of oligometastases with one to three RT treatments may be delayed with 4-6 month depot injections of a GnRH agonist (e.g., Lupron, Eligard, Zoladex, etc.).

I only take issue with the recommendation for non-palliative oligometastatic RT. (They specifically excluded palliative RT from their guidelines.) They state that they recommend delaying treatments that fall into the category of "non-essential procedures that do not have evidence to support their impact on overall survival rates." Treatment of oligometastases is definitely in that category. Yet they state that RT±ADT is the preferred treatment during the pandemic. Anyone with metastases  (any number) should be on ADT or advanced ADT anyway. Painful metastases and those at danger of spinal compression should receive SBRT+ADT.