New transperineal ultrasound-guided biopsy for men in whom PSA is increasing after Miles’ operation
New transperineal ultrasound-guided biopsy for men in whom PSA is increasing after Miles’ operation
Byung Kwan Park, MD
Currently, a prostate biopsy is guided by transrectal ultrasound (US) alone. However, this biopsy cannot be performed in men without an anus. The aim of this study was to show the outcomes of a new transperineal US (TPUS)-guided biopsy technique in patients who underwent Miles' operation.
Between April 2009 and March 2022, TPUS-guided biopsy was consecutively conducted in 9 patients (median, 71 years; range, 61-78 years) with high prostate-specific antigen values (22.60 ng/mL; 6.19-69.7 ng/mL) (Table 1). Their anuses were all removed due to rectal cancer. TPUS-guided biopsy was performed according to information on prostate magnetic resonance imaging. The technical success rate, cancer detection rate, and complication rate were recorded. Tumor sizes were compared between benign and cancer groups using an unpaired t-test with Welch's correction.
Table 1. Patients demographics
Table 2. MRI and biopsy results
Figure 1. A 61-year-old man (case 9) with a high PSA value. A. Diffusion-weighted axial image (b value = 1400 s/mm) shows a 2.0 cm hyperintense mass (white arrows) at the anterior midline base. The patient underwent Miles’ operation due to rectal cancer in 2011. Recently, his PSA was as high as 10.10 ng/mL.
The new TPUS-guided biopsy was successfully performed in all patients. Cancer was detected in 77.8% (7/9) of the patients. These were all categorized as PI-RADS 5 (Table 2). Among them, the detection rate of significant cancer (Gleason score 7 or higher) was 66.7% (6/9). The median tumor size was 2.4 cm (1.7-3.1 cm) (Fig. 1). However, two patients were diagnosed with benign tissue with PI-RADS 3 or PI-RADS 4. Their median tumor size was 1.0 cm (0.8-1.2 cm). There was significant difference between the cancer and benign groups (p = 0.037) in terms of tumor size. Neither post-biopsy bleeding nor infections occurred.
Figure 1B. Apparent diffusion coefficient (ADC) map axial image shows the tumor (white arrows) has low ADC values. The tumor was consistent with PI-RADS 5.
Figure 1C. T2-weighted sagittal image shows that the tumor (white arrows) is located from base to midgland. The white asterisk indicates the absent rectum and anus.
Figure 1D. Longitudinal TPUS image shows a hypoechoic tumor (white arrows). The black arrows indicate the prostate urethra in the path of the biopsy needle. The black asterisk indicates subcutaneous fat compressed by the transducer.
New TPUS-guided biopsy technique may contribute to detecting large PI-RADS 5 prostate cancer in men after Miles' operation.
Figure 1E. Longitudinal TPUS image shows a guideline (white arrowheads) for creating a needle path. It is placed in the center of the tumor (white arrows). However, it does not cross the prostate urethra to avoid injury. The black asterisk indicates subcutaneous fat compressed by the transducer.
Figure 1F. The photograph shows a biopsy needle (black arrowhead) being introduced into the guider (white arrowhead) on the transducer (black asterisk).
