Evaluation of the in vitro and in vivo antitumor activities of vitamin C and K-3 combinations against human prostate cancer.

Neoplasms of the urinary tract and male genital tract account for ;28% of new cancers in males. Prostatic carcinoma is one of the most prevalent malignant tumors of the male reproductive organs, with an estimated 179,300 new cases and 37,000 deaths during the year 2000 in the United States (Greenlee et al. 2000). Treatment options for prostate cancer range from watchful waiting to radical prostectomy and include brachytherapy, external beam irradiation and hormonal ablation therapy (Foster et al. 1997). Although prostate cancer in its early stages is responsive to these standard treatments, patients with hormone-refractory prostate cancer have an overall median survival of 9–18 mo, and no currently available treatment produces a survival advantage (Chen et al. 1998). The lack of efficacy of the eliciting protocols points to the need for the development of effective regimens for treating or preventing these tumors.