AN ASSESSMENT OF THE USEFULNESS OF SERUM PROSTATE-SPECIFIC ANTIGEN LEVEL AND CANCER VOLUME IN BIOPSY SPECIMENS TO PREDICT THE EXTENT OF PROSTATE-CANCER

Objective To evaluate the usefulness of the combination of serum prost ate-specific antigen (PSA) and cancer volume in biopsy specimens as ma rkers to predict the extent of prostate cancer. Patients and methods O f patients presenting at our hospital with urinary symptoms suggesting prostatic disease, 311 (median age 70 years, range 42-88) with either nodules in the prostate detected by digital rectal examination or wit h elevated serum PSA levels (>2.0 ng/mL) underwent systematic biopsy; 69 had prostate cancer. The cancer volume in the biopsy specimens was examined pathologically by measuring the percentage of the biopsy core involved with cancer, the length of cancer tissue per biopsy core and the percentage of cancer in the biopsy specimen. The relationship of serum PSA level, cancer volume in the biopsy specimen and the extent o f disease was volume examined. Results The volume of cancer in the bio psy specimens increased with increasing serum PSA concentration and th e incidence of skeletal metastasis. The number of patients with extrap rostatic disease or bony metastasis was significantly higher for these Japanese patients with a serum PSA of <10 ng/mL. All six patients wit h a positive bone scan and who had a serum PSA level of <10 ng/mL had a larger volume of cancer in their biopsy specimens. Among patients wh o underwent radical prostatectomy and pelvic lymphadenectomy, the inci dence of extraprostatic disease increased with the value of each biops y variable. Among patients with similar serum PSA levels, those showin g higher values for the biopsy variables also showed extraprostatic di sease. Among those with extraprostatic disease, seminal vesicles were involved by cancer in four of six patients with >40% positivity in the biopsy cores, >1.5 mm of cancer per biopsy core or >20% cancer in the biopsy specimens. Lymph node metastasis was found in four of five pat ients with serum PSA levels of >20 ng/mL and a large cancer volume in the biopsy specimen. Conclusions These results that a combination of s erum PSA level and cancer volume in the biopsy specimen could be usefu l markers for predicting the extent of prostate cancer.