Value of functional MRI in evaluation of patients with suspected prostate cancer

Abstract

Purpose: To demonstrate many advantages of using functional MRI in the assessment of prostate cancer compared with traditional invasive TRUS-guided biopsy. Patients and methods: This prospective study included 20 patients with clinical and laboratory (elevated PSA level) suspicion of prostate cancer (age range 43–75 years, mean 65). Patients underwent pretreatment functional MRI and TRUS-guided biopsy. MRI examinations were performed using 1.5-T MRI unit. The MRI protocol included T2WI, DWI, and MRS. TRUS-guided biopsy was done with 9–12 MHz endocavitary transducer. The diagnostic performance of T2WI combined with DWI and MRS was determined with histopathologic data from biopsy as the reference standard. Results: Fifteen patients (75%) proved to have prostate cancer. Gleason score 8 was the most common (46.6%). Most of prostate lesions (17 patients) involved the peripheral zone. The ADCs were significantly lower in prostate cancer than in the prostatitis (p = 0.02). T2WI combined with DWI and MRS had the highest diagnostic performance with a sensitivity, specificity and accuracy of 91.9%, 90.8%, and 88.2% respectively. Conclusion: Functional MRI provided a highly sensitive method in diagnosing and localizing prostate cancer. Being noninvasive, highly sensitive with wider spectrum in nearby pelvic organs assessment in one imaging session, it may totally replace TRUS-guided biopsy.

Keywords

• Prostate cancer
• Transrectal biopsy
• Functional MRI
• Diffusion weighted images
• MRS