['We assessed the prognostic value of baseline prostate specific antigen (PSA) for outcome after high energy transurethral thermotherapy in patients with lower urinary tract symptoms.', 'Data were collected prospectively in 404 consecutive patients treated with high energy transurethral thermotherapy with the Prostatron device (EDAP-Technomed, Lyon, France). Patients were followed a minimum of 1 year. At baseline certain criteria were assessed, including pretreatment PSA, uroflowmetry, ultrasound measurement of prostatic volume, voided and post-void residual urine volume, and International Prostate Symptom Score (I-PSS) and quality of life scores. Outcome assessment included I-PSS, quality of life score and uroflowmetry of peak urine flow. Linear regression analyses were performed to correlate baseline PSA with improved clinical parameters at 12 months of followup. Logistic regression analyses and receiver operating characteristics curves characterized the ability of baseline PSA to discriminate patients with a more or less favorable outcome.', 'An evident linear association was identified for prostate size at baseline and PSA. After 1 year 36 patients were treated again due to transurethral thermotherapy failure and 16 had died, which was not related to lower urinary tract symptoms or treatment for lower urinary tract symptoms. To include re-treated patients in the analyses we considered that their I-PSS, quality of life and peak urine flow values at 1 year were unchanged compared with baseline. Of the 388 evaluable patients an improvement of 50% or more in I-PSS, quality of life and peak urine flow was observed in 57%, 62% and 44%, respectively. Absolute mean changes at 1 year were -9.7, -2 and 5.2 ml. per second for I-PSS, quality of life and peak urine flow, respectively. Neither linear nor logistic regression analysis showed any clinically relevant correlation between baseline PSA and changes in I-PSS (r = -0.004), quality of life (r = -0.135) or peak urine flow (r = 0.105) at 1 year. Receiver operating characteristics curves failed to distinguish more or less favorable outcomes in all evaluated parameters.'] Does baseline prostatic specific antigen predict the outcome of high energy transurethral microwave thermotherapy?