PHI AND MR SPECTROSCOPY AS GUIDELINES TO EARLY DIAGNOSIS AND TREATMENT OF CA PROSTATE IN PATIENTS IN THE GRAY ZONE OF PSA – OUR EXPERIENCES

Abstract

Prostate cancer (CAP) is the most commonly diagnosed type of cancer in men and the second leading cause of cancer death in the world after lung cancer (1). Progress in CAP diagnosis can, in part, be attributed to the discovery of the Prostate Specific Antigen (PSA) in the 1970s. In the 1980s, PSA was primarily approved by the FDA to track patients diagnosed with CAP, and later was approved for CAP diagnostics and introduced as a screening tool for prostate cancer.This wide use of PSAled to a dramatic increase in incidence rates and prostate cancer diagnosis.Today, the prostate cancer mortality rate is approximately 45% lower than in 1992.(2). PSA has low sensitivity and low specificity for CAP. Increased PSA may not be an indicator of clinically significant cancer. The most common cause of a small increase in PSA is Benign Prostate Hyperplasia (BPH). BPH’s incidence increases with age. Approximately 25% of 40-year-old men and 80% of 80-year-old men are estimated to have BPH.(3)(4). Differential diagnosis between malignant and benign disease is particularly challenging when considering that the total range of PSA is from 2ng/mL to 10 ng/mL, where there is a significant overlap between patients with benign and malignant conditions. The low specificity of PSA led to excessive diagnosis of indolent disease and excessive treatment, resulting in high costs for treating patients with elevated PSA. MATERIAL AND METHODS:The study involved 49 patients (observed group) who had TRUS prostate biopsy, based on previousPHI (Prostatic Health Index) and multiparameter MR spectroscopy studies. In patients, an analysis of PathoHistological Postbioptic finding (PHP) from TRUS biopsy (transrectal ultrasound guided biopsy of the prostate) was performed and they were statistically processed and shown through:percentage representation, middle value, table and graphic view of parameters. In the second group of 45 patients (control group) TRUS biopsy was performed only on the basis of PSA findings, physical-digitorectal examination (DRP) and ultrasound examination. The study was conducted for a period of 2 years in patients followed by the Urological department at the City General Hospital 8th of September-Skopje. GOAL: Determining the degree of specificity of PHI and multiparameter MR spectroscopy in early CAP diagnostics in the observed group, Analysis of postbioptic pathohistological finding according to the Glison classification in the observed group(6), Determination of the correlation of PHI and multiparameter MR spectroscopy with PathoHistological Postbioptic results, Determining the criteria for the use of PHI and multiparameter MR spectroscopy when setting an indication of TRUS biopsy according to the study analysis. RESULTS: Of the 49 patients in the observed group with PSA valuesbetween 3.11 ngr/ml to 10.99 ngr/ml, in 63% pf the patients the PHI was with value 55+, the multiparameter MR spectroscopy was valued PIRADS 4 and 5 in 38% of patients, and TRUS biopsy had value for BPH in 61% of patients and CAP in 39% of biopsies. In the control group of a total of 45 patients with PSA values between 3.5 ngr/ml to 11.02 ngr/ml and a positive digitorectal examination, in 62% of patients the findings of TRUS prostate biopsy were as follows: BPH in 64% of patients and CAP in 36% of biopsies. CONCLUSION: Based on the above mentioned results, we can conclude that prebioptic examination gives better prognostics and refers us to a better treatment of the patients. Patients with negative PHI findings and multiparameter MR spectroscopy do not need to be biopsied immediately, but activlymonitored (multiparameter MR spectroscopy once a year) and just in case of a positive finding the next step is to do a prostate biopsy. These kind of diagnosed patients have a higher degree of positive diagnosis, meaning a positive PHP prostate cancer result. Using PHI and multiparameter MR spectroscopy reduces the percentage of overtreated patients, thereby reducing the cost of hospital days and the cost for TRUS prostate biopsy. With reducing the number of unnecessarily biopsyed patients there is also a reduction in the percentage of postbioptic complications in patients.