CT-Guided Biopsy of Entirely Endophytic Small Renal Masses: Diagnostic Rates and Complications Using Standard-Dose and Reduced-Dose CT Protocols.
OBJECTIVE
The objective of this study was to compare diagnostic rates and complications using standard-dose and reduced-dose CT protocols for CT-guided biopsies of entirely endophytic small renal masses.


METHODS
A total of 73 patients with 74 tumors underwent CT-guided biopsy of entirely endophytic small renal masses (≤ 4 cm). Diagnostic rates, histologic findings, radiation doses, complication rates, and procedure duration were assessed by retrospective review of charts and images and were compared for the standard-dose and reduced-dose groups.


RESULTS
Biopsy was performed using the standard-dose CT protocol (mean reference tube current-exposure time setting, 205.0 ± 19.0 [SD] mAs) for 43 lesions, and the reduced-dose CT protocol (reference tube current-exposure time setting, 42.0 ± 7.5 mAs) for 31 lesions. In the reduced-dose group, there were 29 lesions (94%) with diagnostic results. In the standard-dose group, biopsies of 42 lesions (98%) yielded diagnostic results. No complications that needed intervention or hospitalization occurred in either group. The dose-length product (DLP) was significantly higher in the standard-dose group than the reduced-dose group (574 ± 232 vs 152 ± 63 mGy × cm, respectively; p < 0.05). The mean procedure duration did not differ significantly for the two groups.


CONCLUSIONS
Biopsy of entirely endophytic small renal masses that is performed with guidance using a reduced-dose CT protocol gives diagnostic results similar to a standard-dose CT protocol without any increase in complication rate or procedure duration.
1 Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1 Pungnap-dong, Songpa-gu, Seoul 138-736, South Korea.
Mi-Hyun
MH
Kim
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D061705:Image-Guided Biopsy; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D011829:Radiation Dosage; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000009:adverse effects* / Q000379:methods*
CT; percutaneous biopsy; radiation dose; small renal mass