The effect of prostate volume on the yield of needle biopsy.

PURPOSE: Early diagnosis of prostate carcinoma has undergone significant evolution mainly due to the widespread use of serum prostate specific antigen, transrectal ultrasonography and spring loaded biopsy devices. A common dilemma faced by clinicians arises when a negative biopsy is obtained in a patient and there is a high suspicion for prostate carcinoma. The literature reveals a 20 to 40% positive repeat biopsy rate in men with elevated prostate specific antigen who had an initial negative biopsy. We determined the yield of 6 systematic sector biopsies as a function of total gland and peripheral zone volumes. MATERIALS AND METHODS: The database of transrectal ultrasound guided prostate needle biopsies performed at the Department of Urology, University of Washington Medical Center and Veterans Affairs Puget Sound Health Care System was reviewed. The yield of the 6 biopsies was determined as a function of the total gland and peripheral zone volumes. RESULTS: A total of 1,057 men who underwent transrectal ultrasound guided prostate needle biopsies were investigated in our study. Of the men 326 were diagnosed with prostate cancer for a positive biopsy rate of 30.8%. No relationship between gland size and cancer yield was seen using total gland volume compared to the first quartile until the largest quartile when a significantly lower cancer detection rate was noted (odds ratio 1.5). CONCLUSIONS: The positive yield of the systematic 6-sector biopsy decreases significantly when the total gland volume is greater than 55.6 cc or peripheral zone volume is greater than 33.61 cc. In men with smaller prostates 6 systematic sector biopsies should be adequate.

Measurement of complexed PSA improves specificity for early detection of prostate cancer.

OBJECTIVES: Prostate-specific antigen (PSA) is the most useful of all tumor markers. Although the sensitivity is impressive, low specificity results in a lack of cancer detection in a significant proportion of patients undergoing prostate biopsy. Several recent studies have addressed the need for improved specificity. Of all these approaches, the free/total PSA ratio appears to be the most promising. Given that most circulating PSA is complexed to alpha1-antichymotrypsin, and that this moiety represents a greater proportion of the total PSA in those men with carcinoma, we set out to determine whether complexed PSA would improve specificity in the detection of men with prostate cancer. METHODS: Archival sera were obtained from 300 men, 75 of whom had biopsy-proved prostate cancer. All sera had been previously stored at -70 degrees C for variable periods. An investigative assay for complexed PSA (Bayer) was used. The Tandem-R free and total PSA assays (Hybritech) were used according to the manufacturer's recommendations. RESULTS: Among all patients, specificities for the total PSA, free/total PSA, and complexed PSA alone were 21.8%, 15.6%, and 26.7%, respectively, at cutoffs yielding 95% sensitivity. Similar equivalence or superior performance, in terms of specificity relative to the free/total PSA ratio, was seen at other sensitivity thresholds and other total PSA ranges. CONCLUSIONS: Complexed PSA alone performs better than total PSA or the free/total PSA ratio and obviates the need for a second analyte determination. We believe this marker may offer significant enhancement in PSA testing with significant economic advantages.

Repeat ultrasound guided prostate needle biopsy: use of free-to-total prostate specific antigen ratio in predicting prostatic carcinoma.

PURPOSE: Despite being the most useful tumor marker for the diagnosis of patients with prostate cancer, serum prostate specific antigen (PSA) is still hampered by lack of specificity. A negative prostate biopsy is associated with a 20 to 40% incidence of positive repeat biopsy in men with persistently elevated serum PSA levels. We determine whether the free-to-total PSA ratio could be predictive of prostate cancer in men undergoing repeat biopsy. MATERIALS AND METHODS: Archival sera, drawn before the first biopsy, were gathered from 51 men with a total serum PSA of 2 to 15 ng./ml. who underwent repeat prostate needle biopsy for various indications. The percent free PSA was calculated using the Hybritech Tandem-Rt free and total PSA as well as Dianon Systems freet and Hybritech total PSA assays. The free-to-total PSA ratio results between the cancer and noncancer groups were compared using Student's t test. RESULTS: The median Hybritech free-to-total PSA ratio was significantly lower in patients with positive repeat prostate needle biopsy compared to those with negative biopsy (14.9 versus 19.4%, p=0.05). Total PSA as well as the percent Dianon free-to-Hybritech total PSA ratio were not significantly different between the 2 groups of men. CONCLUSIONS: For total PSA in the range of 2 to 15 ng./ml. Hybritech free-to-total PSA ratio appeared to aid in the prediction of cancer on repeat biopsy.

Management of radiation failure for localized prostate cancer.

Due to the historically large number of patients with localized prostate cancer (CAP) treated by radiation therapy, an increasing number of patients are presenting local failure. The currently available concepts regarding its definition as well as management options are reviewed. The literature regarding radiation failure for localized prostate cancer was reviewed. Emphasis was made on articles concerning definition of radiation failure, patient evaluation and restaging and definitive as well as palliative management options. There is definitely a subset of patients with locally recurrent prostate cancer without evidence of metastasis that could potentially benefit from aggressive local therapy. A treatment algorithm is proposed but it should be emphasized that treatment options should be individualized to suit the need of a particular patient.