Ureteral stent insertion for gynecologic interstitial high-dose-rate brachytherapy.

PURPOSE: To determine the utility of ureteral stents in interstitial gynecological brachytherapy. METHODS AND MATERIALS: We reviewed 289 patients with cervix cancer treated with high-dose-rate interstitial brachytherapy who did not have pretreatment hydronephrosis to determine the relative incidence of benign ureteral strictures after treatment. We also did comparative dosimetry analysis in five cases of high-dose-rate brachytherapy. Bilateral ureteral stents were placed during the procedure. Three dosimetry plans were created to determine the impact of modifying clinical target volume (CTV) and applying ureteral dose constraints. In Plan 1, the ureters were contoured and excluded from the CTV and 120% dose constraints were applied. In Plan 2, the ureters were contoured and excluded, but no dose constraints were applied to the ureter. In Plan 3, the CTV was created as if the location of the ureters was unknown and then ureteral dose was determined. RESULTS: There were 11 ureteral strictures observed in 255 nonstented cases and 0 ureteral strictures in 34 stented cases. Plan 1 reduced the ureter dose (D(0.1cc)) by a median 22% (7.0-53.8%) compared with Plan 2 and by a median of 30.9% (12.3-65%). compared with Plan 3. CONCLUSIONS: Placement of stents and ureteral dose constraints facilitates dosimetry and reduces the dose to ureters. Temporary ureteral stents prevent obstruction during interstitial gynecologic brachytherapy and allows the ureters to be addressed as an organ at risk.

A comparative study of stereotactic radiosurgery, hypofractionated, and fractionated stereotactic radiotherapy in the treatment of skull base meningioma.

OBJECTIVES: To compare the outcomes of skull base meningiomas treated with stereotactic radiosurgery (SRS), hypofractionated stereotactic radiotherapy (hFSRT), and fractionated stereotactic radiotherapy (FSRT). METHODS: A total of 220 basal meningiomas in 213 patients were treated using SRS (N=55), hFSRT (N=22), and FSRT (N=143). The median age was 59 years (28 to 84 y). Prior surgery was performed in 74 cases; 39 patients received adjuvant radiotherapy after incomplete resection and 35 patients received salvage radiotherapy after tumor progression. In 146 cases, radiation was the primary therapy. Ten patients had World Health Organization II or III meningiomas. RESULTS: The median follow-up was 32 months (7 to 97 mo). Median tumor volume was 2.8 cm (0.10 to 16.94 cm), 4.8 cm (0.88 to 20.38 cm), and 11.1 cm (0.43 to 214.00 cm) and the median dose was 1250 cGy in 1 fraction to the 80% isodose line (IDL), 2500 cGy in 5 fractions to the 90% IDL, and 5040 cGy in 28 fractions to the 90% IDL for the SRS, hFSRT, and FSRT groups, respectively. Radiographic control was achieved in 91%, 94%, and 95% (P=0.25), whereas clinical response was seen in 89%, 100%, and 91% (P=0.16) in the SRS, hFSRT, and FSRT groups, respectively. CONCLUSIONS: There is no significant difference in the radiographic and clinical response in patients with skull base meningioma treated with SRS, hFSRT, or FSRT and thus gives the clinician the impetus to tailor treatment techniques to the location and size of the tumor at presentation.