Investigating the Effects of Mikei® Red Reishi Essence EX on the Immune System of Prostate Cancer Patients and Patients With Non-cancerous Conditions of the Prostate

Inclusion Criteria: 1. Male age between 50-85 2. Diagnosed with prostate cancer or high-grade PIN within the last 24 months through the most recent biopsy; or patients who have a total PSA level above 4.0 but have not been diagnosed with prostate cancer yet 3. Has not received any prostate cancer therapy including surgery, chemotherapy, hormone therapy, or radiation therapy 4. Clinical Gleason score of the tumor is ≤6 for patients ≤70 years or ≤7 for \>70 years; (non-applicable for non-cancer patients with elevated PSA or high-grade PIN) 5. The clinical stage of the cancer is T1c or below (non-applicable for non-cancer patients with elevated PSA or high-grade PIN) 6. The patients have been recommended for and placed under active surveillance without immediate treatment 7. Able to provide written informed consent Exclusion Criteria: 1. Patients taking mushroom (including reishi) or other herbal products/natural supplements 2. Patients with a known allergy to mushrooms 3. Prisoners 4. Patients who receive treatment with 5-alpha reductase inhibitors (finasteride \[Propecia®, Proscar®,\], or dutasteride \[Avodart®) within 28 days prior to randomization are not eligible. The use of these drugs is not allowed during the patients' study participation. 5. Patients with a history of non-cutaneous malignancy in the previous 5 years are not eligible. 6. Patients taking warfarin, heparin, Aspirin \>81mg/day, or other prescribed blood thinners: Reishi may increase the risk of bleeding. 7. Patients with platelets levels below 139 X 103/ul or history of bleeding disorders 8. Patients undergoing chemotherapy: Reishi may make some chemotherapy drugs less effective. 9. Patients with any known immune disorder, including but not limited to HIV or other primary or secondary immune deficiency diseases, autoimmune diseases, history of or being considered for organ transplants, etc. 10. Patients taking immunosuppressants (Corticosteroids, Calcineurin inhibitors, mTOR inhibitors, IMDH inhibitors, Biologics, Monoclonal antibodies): Reishi can stimulate immune responses. 11. Patients taking cytochrome P450 2E1, 1A2, and 3A sensitive substrate drugs: Reishi may increase the risk of side effects of these drugs. 12. Patient has total bilirubin \>1.5 MG/DL, alanine aminotransferase (ALT) \>51 U/L or aspartate aminotransferase (AST) \>46 U/L.