A new look at bladder neck obstruction by the food and drug administration regulators: guide lines for investigation of benign prostatic hypertrophy.

A basic assumption of current guide lines to test drug therapy for benign prostatic hypertrophy is that the clinical disease is caused by bladder neck obstruction and its sequelae and complications. Asymptomatic non-prostatic hypertrophy, no matter how large the adenoma, is considered to be a pre-clinical phase of the disease as long as bladder trabeculation, impairment of the flow rate and residual urine are absent. The guide lines recognize that histological changes and gross anatomical enlargement of the prostate are the essence of the disease but objective signs of current therapeutic relief of symptoms lend themselves more practically to measurement of progression or remission, whereas no current drug has a clear enough effect on prostatic histology to predict subsidence of the clinical picture. Since no one criterion or single test serves this purpose a cluster of symptoms, with flow rate and residual urine, provides the hardest data. It would be preferable for each patient to serve as his own control in a prospective double-blind randomized study, since the literature shows no uniformity of approach, methodology, patient population or other useful data for clinical norms. Guide lines have been developed with the aid of clinical pharmacologists, biostatisticians, lawyers and government officials and approved by the Food and Drug Administration. Misconceptions outside of the profession of Urology need to be dispelled and further research in methodology, urodynamics, ultrasonic evaluation of the prostate, definition of symptoms, criteria for efficacy, etiology of the disease, and mode of action of drugs, placebo and surgery were highlighted. The literature does not have an overabundance of data but does contain evidence of definite but weak drug efficacy in the treatment of this condition.