Are three substages of clinical B prostate carcinoma useful in predicting disease-free survival?

The B1 nodule, a 1.5 cm area of induration surrounded on at least two sides by prostatic tissue of normal consistency, was defined by Jewett in 1968 as the stage of prostatic cancer best suited for treatment and cure by radical prostatectomy (RP). The area of prostatic induration suitable for RP was subsequently extended to less than one lobe (Stage B1); this extension of induration was supported by the study of Walsh and Jewett in 1980 showing a 51 percent survival free-of-disease at fifteen-year follow-up. Subsequently, clinical staging systems evolved which substaged clinical B into three categories of induration: B1N = less than 1.5 cm nodule, B1 = greater than 1.5 cm but less than one lobe, and B2 = one lobe or both lobes. To determine if digital assessment of these progressively greater degrees of induration would translate into different intervals to first progression, whether local or distant, we reviewed prostate diagrams and descriptions of all Stage B patients treated by Iodine-125 interstitial implant and external beam radiation therapy between 1974 and 1985 at our institution. Forty-six patients had B1 nodules, 78 patients B1 (less than one lobe), and 52 patients B2 (one lobe or greater). Mean follow-up was fifty-five months. We found B1N, which was also associated with well-differentiated grade and a normal acid phosphatase, to have the longest interval to progression.