The application of fusion imaging in patients who received initial prostate biopsy

Abstract

Objective To investigate the application of fusion imaging in the initial prostate biopsy. Methods Retrospective analysis was made on 40 patients who underwent initial ultrasound-guided prostate biopsy in Shanghai Jiao Tong University Affiliated 6th People′s Hospital from August 2014 to May 2015. All patients underwent preoperative magnetic resonance imaging (MRI) scans one week prior to surgery and the results showed that all patients had suspicious positive prostate cancer lesions, while there were no positive findings in the same area in sonography. All patients with prostate cancer have been confirmed by pathologic examination. Image fusion technology was used to guide the biopsy of lesions which were suspected as prostate cancer by MRI, and then the prostate underwent systematic biopsy by 10 needles under the guide of ultrasound. R×C Chi-square test was used to compare the positive ratio among imaging fusion biopsy, systematic biopsy and combined method in the diagnosis of prostate cancer. Fourfold table Chi-square test was used to compare to undetected rate between fusion imaging biopsy and systematic biopsy in the diagnosis of prostate cancer. The differences of detection rate in the Gleason score more than 7 points of prostate cancer between fusion imaging biopsy and systematic biopsy was compared by Fisher exact test. Results In this group of 40 patients with prostate biopsy, 14 cases (35.0%) were diagnosed prostate cancer by systematic biopsy, 19 cases (47.5%) were diagnosed prostate cancer by image fusion biopsy, and 22 cases (55.0%) were diagnosed prostate cancer by systematic biopsy combined with image fusion. The difference of diagnostic positive rate among combined method of biopsy, image fusion biopsy and systematic biopsy had not statistically significant (P>0.05). Three cases (13.6%, 3/22) of prostate cancer patients were missed in image fusion method group, and 8 cases (36.4%, 8/22) of prostate cancer patients have not been diagnosed by systematic biopsy, which indicated the undetected rate of systematic biopsy is higher than that of image fusion biopsy in prostate cancer diagnosis, and there was a statistical difference between the two groups (χ2=8.338, P=0.005). Among 19 cases of prostate cancer patients who were diagnosed by image fusion biopsy method, Gleason score were greater than 7 points in 15 cases (78.9%, 15/22). Among 14 cases of prostate cancer patients who were diagnosed by systematic biopsy method, Gleason score were greater than 7 points in 6 cases (42.9%, 6/14). The positive rate of Gleason score ≥ 7 points in fusion imaging biopsy was higher than that of systematic biopsy, which had a statistical difference (Fisher exact probability method, P=0.039). Conclusion Image fusion method can be used to reduce the undetected rate of prostate cancer and improve the detection rate of the high-grade prostate cancer. Key words: Prostatic neoplasms; biopsy, needle; Ultrasound; Magnetic resonance imaging