Introduction:
Testosterone promotes the initial development of androgen-dependent prostate cancer. This is the basis for androgen ablation treatment, which attenuates, but does not terminate, the malignancy. Instead, it leads to prolactin-dependent malignancy; in which patient death generally occurs within 5 years. This report describes the novel treatment of a patient; which terminated androgen-independent prostate cancer.
Results:
Patient "XY" was diagnosed with prostate malignancy and metastases. He received hormonal androgen ablation treatment, chemotherapy, and radiation treatment. He developed androgen-independent prostate cancer; with expected death in 2-3 years. He was treated with cabergoline (dopamine agonist) treatment, which decreased the plasma prolactin 88%; by inhibiting the pituitary production of prolactin. The subsequent PET scan (positron emission tomography) revealed the absence of malignancy; and the CTC (circulating tumor cells) decreased from count=5.4 to count=0.
Discussion:
The cause of androgen-independent malignancy has been unknown, and an effective chemotherapy did not exist. The activities of normal and malignant prostate cells are regulated primarily by testosterone. When testosterone availability diminishes; prolactin regulation is manifested. This is represented when androgen ablation results in the development of prolactin-dependent malignancy. An effective chemotherapy would be targeted to eliminate the plasma prolactin-manifestation of the androgen-independent malignancy.
Conclusions:
This report of a novel chemotherapy for androgen-independent malignancy corroborates our understanding of the implications of prolactin in its development and treatment. There are about 165,000 cases/year with 25,000 deaths/year in the U.S.; and 1.0 million cases/year with 260,000 deaths/year worldwide. Those patients with androgen-independent prostate cancer can now employ this cabergoline treatment to prevent or terminate this deadly type of prostate cancer.