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138 Intra-operative treatment planning: A way to improve dosimetry in prostate brachytherapy
CARO 2 0 0 6
September 13-16
138 Intra-operative Treatment Planning: A Way to Improve Dosimetry in Prostate Brachytherapy W. Foster, S. Aubin, N. Varfalvy, L. Beaulieu, A-G. Martin, E. Vigneault L'HoteI-Dieu de Quebec, CHUQ, University Laval, Quebec, Quebec william, foster. 1 @ula val. ca
Purpose: To demonstrate the advantage of intra-operative (IO) over pre-operative planning by evaluating the impact of patients position on urethra and prostate dosimetry after I125 implant. Material and Methods: Real time dosimetry of a group of 15 patients treated with I125 permanent prostate implant was evaluated with changing leg arid/or urethras position. 3D ultrasound was used to plan seed implantation. Scans were repeated after downward movements of patient's urethra and legs. The initial IO clinical plans were applied to these new scans. Doses to urethra (D5, V150) and prostate (D90, V200) were compared for the different positions. Results: The mean value of prostates D90 went from 194, 2 Gy to 172, 5 Gy after a urinary catheter displacement (p=0.001) and to 170, 2 Gy when legs were moved. The maximal urethras D5 variation observed for each patient ranged from 4, 2 to 70, 7%, with a mean increase of 26, 6%. A third of the patients (5/15) presented values of urethras D5 beyond 300 Gy. A mean 17, 7% variation of the urethras V150 was observed for the 15 patients, going from an initial 8,1% to 22,8% with a displacement of the urethra (p=0.024) and to 28, 7% when moving the legs (p=0.001). Conclusions: Patient positioning has an impact on dosimetry. We observed a significant decrease of the prostates D90 and V200 combined with a significant increase of urethras D5 and V150 when moving patients legs and even the urethra catheter. This translates in a clear dosimetric advantage of intraoperative dosimetry over pre-planning. 139 Comparative Study of Dosimetry between High-Dose Rate and Permanent Prostate Implant Brachytherapies in Patients with Prostate Adenocarcinoma Y. Wang, R. Sankreacha, A. Al-Hebshi, A. Loblaw, G. Morton Toronto Sunnybrook Regional Cancer Centre, University of Toronto, Toronto, Ontario yonqfin, wana@rmo, uhn. on. ca
Purpose: To compare the dose coverage, conformity and homogeneity between high-dose rate (HDR) brachytherapy and permanent prostate implant (PPI) with Iodine-125 in the treatment of prostate adenocarcinoma. Methods: From January 2003 to August 2004, 54 patients (108 implants) underwent HDR brachytherapy of prostate cancer with transperineal afterloading technique using Iridium192 stepping source. Of a total of 153 patients who underwent PPI brachytherapy with Iodine-125 during the same time period, 72 patients were randomly selected for the purpose of comparison of dosimetric parameters with those patients who underwent HDR brachytherapy. PPI preplan was done based on transrectal ultrasound volume study with Varian Variseed Brachytherapy module, and transperineal implantation of Iodine-125 seeds was performed according to the preplan. Postplan was done using CT scan one month after implant. Dosimetric parameters of HDR were compared to the parameters of PPI preplan and postplan respectively. Results: Comparing to PPI preplan, HDR brachytherapy had lower D90 (dose covering 90% of the prostate volume; 120.2% vs 111.6%; p<0.001). Conclusions: HDR brachytherapy of the prostate has better dose coverage, conformity and homogeneity compared to PPI. 140 Sexual Function Following Brachytherapy J. Crook, D. Webster, D. Virtue
Iodine
125
Prostate
$41
Princes Margaret Hospital, University of Toronto, Toronto, Ontario ]uanita. crook@rmp, uhn. on. ca Purpose: Brachytherapy may have an advantage over surgery as a definitive treatment of prostate cancer by decreasing the impact on sexual function. Methods and Materials: Since March 1999, data has been collected prospectively for 740 Iodine 125 prostate implants. Erectile function is recorded at each visit. PDE-5 inhibitors (PDE-5i: sildenafil or similar) are offered for any reported decline. To validate physician reported data, 101 consecutive patients with baseline potency and fluency in English were approached to complete an anonymous on-line survey which included the five questions of the IIEF (International Index of Erectile Function: score/25), with the addition of questions on ejaculatory volume and use of PDE-5i. Results: For the entire population, median age was 64 years (range 45-83). Tumour parameters were Tlc: 65% , T2a: 35% , Gleason score 6: 92% and median PSA: 6.5 ng/ml. 85% reported baseline potency (16% with PDE-5i). At mean 19 months (range to 72 months), 85% of previously potent men reported satisfactory erections. PDE-5i use had increased to 34%. For the 101 men who completed the survey, median age was 65; mean interval since brachytherapy 22.9 months (range 3-63). Median IIEF score was 20. PDE-5i used sometimes by 25%, always by 30%, never by 46%. There was no difference in the IIEF scores between users (median score 19.5) and nonusers (median 20), nor between the first year of follow-up (median 19) and >36 months (median: 22), although PDE-5i use increased over time (45% in first year vs 63% >36 months). IIEF score >15/25 was reported in 81% . Ejacutatory volume was normal: 12%, reduced: 72% and absent: 17%. Conclusions: Physician-reported potency (yes/no) agreed well with patient-reported data using the I]EF instrument. Mild to moderate degrees of ED are more likely to be detected with a validated questionnaire. Although the use of PDE 5ifs increases over time, brachytherapy is associated with a high rate of maintenance of erectile function. 141 Acute and Late Urinary Toxicity in 606 Prostate Brachytherapy Patients M. Keyes 1, S. Miller z, V. Moravan 2, H. Pai4, W. Kwan 3, M. Liu 3, J. Morris I, R. Halperin 5, 7-. Pickles 1 British Columbia Cancer Agency, Vancouver Cancer Centre, Vancouver, British Columbial; British Columbia Cancer Agency, Vancouver, British Columbia2; British Columbia Cancer Agency, Fraser Valley Cancer Centre, Surrey, British Columbia3; British Columbia Cancer Agency, Vancouver Island Cancer Centre, Vancouver, British Columbia4; British Columbia Cancer Agency, Cancer Centre for Southern Interior, Kelowna, British Columbia 5 mkeyes@bccancer, bc, ca
Purpose: To describe acute and late urinary toxicity and associated predictive factors in 606 uniformly treated consecutive prostate brachytherapy (PB) patients. Materials and Methods: Patients were implanted July 1998 January 2003. Median follow was 49.5 months (range 34-89). Baseline and post-treatment IPSS, urinary QOL (scale from 0 = delighted to 6 = terrible) were prospectively collected. Acute urinary toxicity was measured at six weeks, subacute at six months and late on >12 months after PB using RTOG scale. Kaplan-Meier curves with the log-rank test were used for all factors. Results: Median baseline IPSS was 5. Median IPSS at six weeks, 6, 12 and 60 months were 19, 11 and 8 and 6 respectively. The IPSS returned to baseline in 83% of the entire cohort: 37%, 74% and 90% by 6, 12 and 24 months respectively. Seventeen percent of the patients, who never returned IPSS to baseline, had lower pre-treatment IPSS scores. Patient factors (age, iIPSS, diabetes, prostate size, androgen suppression) and dosimetric factors (number of needles, D90, date of implant-learning curve) will be examined using univariate and multivariate analyses, for association
September 13-16
138 Intra-operative Treatment Planning: A Way to Improve Dosimetry in Prostate Brachytherapy W. Foster, S. Aubin, N. Varfalvy, L. Beaulieu, A-G. Martin, E. Vigneault L'HoteI-Dieu de Quebec, CHUQ, University Laval, Quebec, Quebec william, foster. 1 @ula val. ca
Purpose: To demonstrate the advantage of intra-operative (IO) over pre-operative planning by evaluating the impact of patients position on urethra and prostate dosimetry after I125 implant. Material and Methods: Real time dosimetry of a group of 15 patients treated with I125 permanent prostate implant was evaluated with changing leg arid/or urethras position. 3D ultrasound was used to plan seed implantation. Scans were repeated after downward movements of patient's urethra and legs. The initial IO clinical plans were applied to these new scans. Doses to urethra (D5, V150) and prostate (D90, V200) were compared for the different positions. Results: The mean value of prostates D90 went from 194, 2 Gy to 172, 5 Gy after a urinary catheter displacement (p=0.001) and to 170, 2 Gy when legs were moved. The maximal urethras D5 variation observed for each patient ranged from 4, 2 to 70, 7%, with a mean increase of 26, 6%. A third of the patients (5/15) presented values of urethras D5 beyond 300 Gy. A mean 17, 7% variation of the urethras V150 was observed for the 15 patients, going from an initial 8,1% to 22,8% with a displacement of the urethra (p=0.024) and to 28, 7% when moving the legs (p=0.001). Conclusions: Patient positioning has an impact on dosimetry. We observed a significant decrease of the prostates D90 and V200 combined with a significant increase of urethras D5 and V150 when moving patients legs and even the urethra catheter. This translates in a clear dosimetric advantage of intraoperative dosimetry over pre-planning. 139 Comparative Study of Dosimetry between High-Dose Rate and Permanent Prostate Implant Brachytherapies in Patients with Prostate Adenocarcinoma Y. Wang, R. Sankreacha, A. Al-Hebshi, A. Loblaw, G. Morton Toronto Sunnybrook Regional Cancer Centre, University of Toronto, Toronto, Ontario yonqfin, wana@rmo, uhn. on. ca
Purpose: To compare the dose coverage, conformity and homogeneity between high-dose rate (HDR) brachytherapy and permanent prostate implant (PPI) with Iodine-125 in the treatment of prostate adenocarcinoma. Methods: From January 2003 to August 2004, 54 patients (108 implants) underwent HDR brachytherapy of prostate cancer with transperineal afterloading technique using Iridium192 stepping source. Of a total of 153 patients who underwent PPI brachytherapy with Iodine-125 during the same time period, 72 patients were randomly selected for the purpose of comparison of dosimetric parameters with those patients who underwent HDR brachytherapy. PPI preplan was done based on transrectal ultrasound volume study with Varian Variseed Brachytherapy module, and transperineal implantation of Iodine-125 seeds was performed according to the preplan. Postplan was done using CT scan one month after implant. Dosimetric parameters of HDR were compared to the parameters of PPI preplan and postplan respectively. Results: Comparing to PPI preplan, HDR brachytherapy had lower D90 (dose covering 90% of the prostate volume; 120.2% vs 111.6%; p<0.001). Conclusions: HDR brachytherapy of the prostate has better dose coverage, conformity and homogeneity compared to PPI. 140 Sexual Function Following Brachytherapy J. Crook, D. Webster, D. Virtue
Iodine
125
Prostate
$41
Princes Margaret Hospital, University of Toronto, Toronto, Ontario ]uanita. crook@rmp, uhn. on. ca Purpose: Brachytherapy may have an advantage over surgery as a definitive treatment of prostate cancer by decreasing the impact on sexual function. Methods and Materials: Since March 1999, data has been collected prospectively for 740 Iodine 125 prostate implants. Erectile function is recorded at each visit. PDE-5 inhibitors (PDE-5i: sildenafil or similar) are offered for any reported decline. To validate physician reported data, 101 consecutive patients with baseline potency and fluency in English were approached to complete an anonymous on-line survey which included the five questions of the IIEF (International Index of Erectile Function: score/25), with the addition of questions on ejaculatory volume and use of PDE-5i. Results: For the entire population, median age was 64 years (range 45-83). Tumour parameters were Tlc: 65% , T2a: 35% , Gleason score 6: 92% and median PSA: 6.5 ng/ml. 85% reported baseline potency (16% with PDE-5i). At mean 19 months (range to 72 months), 85% of previously potent men reported satisfactory erections. PDE-5i use had increased to 34%. For the 101 men who completed the survey, median age was 65; mean interval since brachytherapy 22.9 months (range 3-63). Median IIEF score was 20. PDE-5i used sometimes by 25%, always by 30%, never by 46%. There was no difference in the IIEF scores between users (median score 19.5) and nonusers (median 20), nor between the first year of follow-up (median 19) and >36 months (median: 22), although PDE-5i use increased over time (45% in first year vs 63% >36 months). IIEF score >15/25 was reported in 81% . Ejacutatory volume was normal: 12%, reduced: 72% and absent: 17%. Conclusions: Physician-reported potency (yes/no) agreed well with patient-reported data using the I]EF instrument. Mild to moderate degrees of ED are more likely to be detected with a validated questionnaire. Although the use of PDE 5ifs increases over time, brachytherapy is associated with a high rate of maintenance of erectile function. 141 Acute and Late Urinary Toxicity in 606 Prostate Brachytherapy Patients M. Keyes 1, S. Miller z, V. Moravan 2, H. Pai4, W. Kwan 3, M. Liu 3, J. Morris I, R. Halperin 5, 7-. Pickles 1 British Columbia Cancer Agency, Vancouver Cancer Centre, Vancouver, British Columbial; British Columbia Cancer Agency, Vancouver, British Columbia2; British Columbia Cancer Agency, Fraser Valley Cancer Centre, Surrey, British Columbia3; British Columbia Cancer Agency, Vancouver Island Cancer Centre, Vancouver, British Columbia4; British Columbia Cancer Agency, Cancer Centre for Southern Interior, Kelowna, British Columbia 5 mkeyes@bccancer, bc, ca
Purpose: To describe acute and late urinary toxicity and associated predictive factors in 606 uniformly treated consecutive prostate brachytherapy (PB) patients. Materials and Methods: Patients were implanted July 1998 January 2003. Median follow was 49.5 months (range 34-89). Baseline and post-treatment IPSS, urinary QOL (scale from 0 = delighted to 6 = terrible) were prospectively collected. Acute urinary toxicity was measured at six weeks, subacute at six months and late on >12 months after PB using RTOG scale. Kaplan-Meier curves with the log-rank test were used for all factors. Results: Median baseline IPSS was 5. Median IPSS at six weeks, 6, 12 and 60 months were 19, 11 and 8 and 6 respectively. The IPSS returned to baseline in 83% of the entire cohort: 37%, 74% and 90% by 6, 12 and 24 months respectively. Seventeen percent of the patients, who never returned IPSS to baseline, had lower pre-treatment IPSS scores. Patient factors (age, iIPSS, diabetes, prostate size, androgen suppression) and dosimetric factors (number of needles, D90, date of implant-learning curve) will be examined using univariate and multivariate analyses, for association