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1016 poster FOCAL SALVAGE FOR PROSTATE CANCER RECURRENCES.
P ROSTATE CANCER
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respectively. Conclusions: Daily CBCT with our rescan protocol may be promising to reduce the inter-fraction motions of the prostate, which were as small as 1 mm. The rescan was needed in 5% of the IMRT fractions and could resolve the severe misregistration mainly caused by excessive rectal gas. 1014 poster EFFICACY OF KETOCONAZOLE AND DIETHYLSTILBESTROL IN HORMONE REFRACTORY PROSTATE CANCER M. Solak Mekic1 , M. Solaric1 , V. Mataga2 , T. Krnic1 , H. Sobat1 1 C LINICAL H OSPITAL "S ISTERS OF C HARITY "/U NIVERSITY H OSPITAL FOR T UMORS, Department of Radiation Oncology, Zagreb, Croatia 2 U NIVERSITY H OSPITAL FOR T UMORS, Zagreb, Croatia Purpose: Diethylstilbestrol (DES), a synthetic ethynyl estrogen, and intermediate dose ketoconazole (IDK) and hydrocortisone, a combination of antimycotic and corticosteroid, are often used as salvage therapy after several hormone manipulations. We investigated their efficacy in patients with hormone refractory prostate cancer (HRPC). Materials: A retrospective review of medical records of 32 HRPC pts receiving IDK and 19 pts receiving DES from Jan 2005 to Dec 2009. Results: Prior to IDK, patients received four lines of hormonal therapy. The median baseline serum PSA level was 75.8 ng/ml (range 1.75-563.3). A PSA response (defined by ≥ 50% decline in baseline PSA) or any PSA decline were observed in 5 (17.9%) and 11 (39.3%) pts, respectively.For the entire study group, the median time to progression (TTP) was 2.25 months (interquartile range (IQR) 2.0-5.75 mths), and the median survival was 11 months (IQR 5-21 mths). In PSA responders, TTP was significantly longer (7 mths) than in PSA non-responders (2.0 mths) (p=0.014). TTP was also significantly longer (6 mths) in patients with any PSA decline than in the group without decline (2.0 mths)(p<0.001). Intolerable side effects caused IDK discontinuation in 8 (28.6%) pts. Prior to DES, patients received one line of hormonal therapy more than the IDK group. The median baseline serum PSA value was 43.1 (IQR 7.1-118.8) and the median treatment duration was 8 months (IQR 3.9-10.5mths). Any PSA decline and >50% decline were observed in 11 (68.7%) and 6 (37.5%) pts, respectively. The median TTP was 7.25 months (IQR 4.0-9.25 mths) and the median overall survival was 12 months (IQR 7.4-17.5 mths). Using the >50% response criteria, the median TTP for responders was 8.25 mths compared to 4.5 mths for non-responders (p=0.093). DES toxicity was reported in only one patient. Conclusions: Diethylstilbestrol and ketoconazole are a valuable option for HRPC patients. DES can induce prolonged responses and is well tolerated. Early identified PSA responders to IDK will benefit from this therapy. A substantial proportion of patients discontinue therapy due to intolerable side effects. Long responses are more likely to occur in men initiating IDK or DES early in the course of their disease. 1015 poster EVALUATION OF ROTATIONAL IMRT FOR THE TREATMENT OF PROSTATE CANCER PATIENTS WITH PROSTHETIC HIP R. Venkitaraman1 , A. Esmail2 , S. Boston1 , H. James1 , C. D. Scrase1 1 S UFFOLK O NCOLOGY C ENTRE T HE I PSWICH H OSPITAL NHS T, Ipswich Suffolk, United Kingdom 2 M OUNT V ERNON H OSPITAL, Northwood Middlesex, United Kingdom Purpose: To evaluate the potential advantage of rotational IMRT with Varian RapidArc for treating prostate cancer patients with prosthetic hip, and a dosimetric comparison with 3D CRT. Materials: Five prostate cancer patients with prosthetic hip, due to receive radical radiotherapy, had planning CT scans. The CTV was defined as prostate and seminal vesicles, PTV as CTV plus margin of 1 cm. Prescribed dose to PTV was 70Gy. Plans were generated for each sets of scans for 3D CRT and Varian RapidArc.18 MV 3D CRT plans were created avoiding direct beam entry through the prosthetic hip. RapidArc plans utilised a single 6MV arc rotating from 179.90 to 180.10 , incorporating an avoidance sector during optimisation to prevent beam entry through the prosthesis. A comparison of the DVH by the two techniques with regards to the PTV coverage and radiation dose received by the OAR was undertaken, utilising the paired samples T test, and p value of 0.05 was considered significant. Results: Adequate PTV coverage was obtained with both plans with a mean conformity index of 0.5 for Rapid Arc and of 0.6 for 3D CRT plan(p=0.28). The average maximum dose to bladder (71.2 Vs 74.6; p=0.003) and opposite hip (36.7 Vs 49.8; p=0.021) were lesser with RapidArc plan compared to the 3D CRT plan, while that for rectum (71.5 Vs 72; p=0.105) was similar. The average mean dose to the rectum (46.7 Vs 52.8; p=0.209), bladder (31.3 Vs 33.5; p=0.268) and opposite hip (20.5 Vs 31.3; p=0.036) were lesser with RapidArc plan compared to the 3D CRT, though not statistically significant. Comparison of the individual DVHs also suggest a reduction in the bladder and rectal volume receiving each dose level for the Rapid Arc plans compared to the 3D CRT plan (table).
Conclusions: Rotational IMRT with Varian Rapid Arc enables optimal delivery of the prescribed dose to the PTV, whilst reducing the dose to the OAR, in comparison with 3D CRT in patients with prosthetic hip receiving radical radiotherapy for prostate cancer, potentially reducing the acute and late sideeffects of radiotherapy. 1016 poster FOCAL SALVAGE FOR PROSTATE CANCER RECURRENCES. M. Peters1 , M. Moman1 , U. van der Heide1 , M. Moerland1 , S. Franken1 , J. J. Battermann1 , M. van Deursen1 , M. van Vulpen1 1 U.M.C. U TRECHT, Utrecht, Netherlands Purpose: Recurrent prostate cancer after previous radiotherapy can be treated with a salvage treatment of the entire prostate. Data from salvage prostatectomy, salvage cryotherapy or salvage brachytherapy series show high rates of severe (grade 3 or higher) toxicity, even up to 30%. This causes the urology community to be reluctant with regard to salvage treatments to the entire prostate. Currently, Dynamic-Contrast Enhanced (DCE-)MRI allows localization of the recurrence within the prostate and thus enables focal salvage. We hypothesize severe toxicity rates will be significantly reduced by using focal salvage. Materials: In 16 patients with biopsy proven local recurrent prostate cancer focal salvage was performed by I-125 brachytherapy. Recurrences were located by DCE-MRI and confirmed by a 12-core biopsy scheme. Prescription dose to the recurrence was 144Gy, GEC-ESTRO guidelines with regard to sparing of rectum and bladder were met. Toxicity was recorded using the Common Toxicity Criteria (CTC) and quality of life was measured using Rand36, EORTC-C30 and-PR25. Results: With a minimum follow-up of six months, grade 3 gastro-intestinal toxicity was observed in only 1 patient. Quality of life was not impaired. Conclusions: Based on these preliminary data we conclude focal salvage seemed to be technically and clinically feasible, with an acceptable toxicity rate. 1017 poster GENITOURINARY TOXICITY IN PROSTATE HDR BRACHYTHERAPY E. Aleknavicius1 , A. Burneckis1 , A. Ivanauskas1 1 I NSTITUTE OF O NCOLOGY V ILNIUS U NIVERSITY, Clinic for Radiation Therapy, Vilnius, Lithuania Purpose: In Vilnius University Oncology Institute we started to perform HDR (high dose rate) prostate brachytherapy technique in combination with 3 D conformal external radiotherapy for high and intermediate prostate cancer patients in 2009-07. We treated 16 pts. until 2010-12. The follow-up of these patients was performed. The main purposes were to determine: acute genitourinary (GU) and gastrointestinal side effects and toxicities, PSA value dynamics Materials: We performed combined modality (CM) treatment using brachytherapy machine Varisource 200 with Iridium 195 (125Ir) source for brachytherapy and Varian linear accelerator for external beam therapy. The prescribed BT dose was 9,5Gy (26 izoGy) to the prostate and basis of seminal vesicals and after 10-14 days EBRT 50 Gy to the prostate and whole seminal vesicals and regional lymph nodes (if lymph node irradiation was needed. Treated pts. were: cT2b cT3b, Gleason score 6-7 and initial PSA value 4,13 50 ng/ml (intermediate and high risk group prostate cancer patients), median age 56 years. The prostate volume 22 46 ml. 14 of these patients received neoadjuvant antiandrogen hormonal treatment (1 12 moths).
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respectively. Conclusions: Daily CBCT with our rescan protocol may be promising to reduce the inter-fraction motions of the prostate, which were as small as 1 mm. The rescan was needed in 5% of the IMRT fractions and could resolve the severe misregistration mainly caused by excessive rectal gas. 1014 poster EFFICACY OF KETOCONAZOLE AND DIETHYLSTILBESTROL IN HORMONE REFRACTORY PROSTATE CANCER M. Solak Mekic1 , M. Solaric1 , V. Mataga2 , T. Krnic1 , H. Sobat1 1 C LINICAL H OSPITAL "S ISTERS OF C HARITY "/U NIVERSITY H OSPITAL FOR T UMORS, Department of Radiation Oncology, Zagreb, Croatia 2 U NIVERSITY H OSPITAL FOR T UMORS, Zagreb, Croatia Purpose: Diethylstilbestrol (DES), a synthetic ethynyl estrogen, and intermediate dose ketoconazole (IDK) and hydrocortisone, a combination of antimycotic and corticosteroid, are often used as salvage therapy after several hormone manipulations. We investigated their efficacy in patients with hormone refractory prostate cancer (HRPC). Materials: A retrospective review of medical records of 32 HRPC pts receiving IDK and 19 pts receiving DES from Jan 2005 to Dec 2009. Results: Prior to IDK, patients received four lines of hormonal therapy. The median baseline serum PSA level was 75.8 ng/ml (range 1.75-563.3). A PSA response (defined by ≥ 50% decline in baseline PSA) or any PSA decline were observed in 5 (17.9%) and 11 (39.3%) pts, respectively.For the entire study group, the median time to progression (TTP) was 2.25 months (interquartile range (IQR) 2.0-5.75 mths), and the median survival was 11 months (IQR 5-21 mths). In PSA responders, TTP was significantly longer (7 mths) than in PSA non-responders (2.0 mths) (p=0.014). TTP was also significantly longer (6 mths) in patients with any PSA decline than in the group without decline (2.0 mths)(p<0.001). Intolerable side effects caused IDK discontinuation in 8 (28.6%) pts. Prior to DES, patients received one line of hormonal therapy more than the IDK group. The median baseline serum PSA value was 43.1 (IQR 7.1-118.8) and the median treatment duration was 8 months (IQR 3.9-10.5mths). Any PSA decline and >50% decline were observed in 11 (68.7%) and 6 (37.5%) pts, respectively. The median TTP was 7.25 months (IQR 4.0-9.25 mths) and the median overall survival was 12 months (IQR 7.4-17.5 mths). Using the >50% response criteria, the median TTP for responders was 8.25 mths compared to 4.5 mths for non-responders (p=0.093). DES toxicity was reported in only one patient. Conclusions: Diethylstilbestrol and ketoconazole are a valuable option for HRPC patients. DES can induce prolonged responses and is well tolerated. Early identified PSA responders to IDK will benefit from this therapy. A substantial proportion of patients discontinue therapy due to intolerable side effects. Long responses are more likely to occur in men initiating IDK or DES early in the course of their disease. 1015 poster EVALUATION OF ROTATIONAL IMRT FOR THE TREATMENT OF PROSTATE CANCER PATIENTS WITH PROSTHETIC HIP R. Venkitaraman1 , A. Esmail2 , S. Boston1 , H. James1 , C. D. Scrase1 1 S UFFOLK O NCOLOGY C ENTRE T HE I PSWICH H OSPITAL NHS T, Ipswich Suffolk, United Kingdom 2 M OUNT V ERNON H OSPITAL, Northwood Middlesex, United Kingdom Purpose: To evaluate the potential advantage of rotational IMRT with Varian RapidArc for treating prostate cancer patients with prosthetic hip, and a dosimetric comparison with 3D CRT. Materials: Five prostate cancer patients with prosthetic hip, due to receive radical radiotherapy, had planning CT scans. The CTV was defined as prostate and seminal vesicles, PTV as CTV plus margin of 1 cm. Prescribed dose to PTV was 70Gy. Plans were generated for each sets of scans for 3D CRT and Varian RapidArc.18 MV 3D CRT plans were created avoiding direct beam entry through the prosthetic hip. RapidArc plans utilised a single 6MV arc rotating from 179.90 to 180.10 , incorporating an avoidance sector during optimisation to prevent beam entry through the prosthesis. A comparison of the DVH by the two techniques with regards to the PTV coverage and radiation dose received by the OAR was undertaken, utilising the paired samples T test, and p value of 0.05 was considered significant. Results: Adequate PTV coverage was obtained with both plans with a mean conformity index of 0.5 for Rapid Arc and of 0.6 for 3D CRT plan(p=0.28). The average maximum dose to bladder (71.2 Vs 74.6; p=0.003) and opposite hip (36.7 Vs 49.8; p=0.021) were lesser with RapidArc plan compared to the 3D CRT plan, while that for rectum (71.5 Vs 72; p=0.105) was similar. The average mean dose to the rectum (46.7 Vs 52.8; p=0.209), bladder (31.3 Vs 33.5; p=0.268) and opposite hip (20.5 Vs 31.3; p=0.036) were lesser with RapidArc plan compared to the 3D CRT, though not statistically significant. Comparison of the individual DVHs also suggest a reduction in the bladder and rectal volume receiving each dose level for the Rapid Arc plans compared to the 3D CRT plan (table).
Conclusions: Rotational IMRT with Varian Rapid Arc enables optimal delivery of the prescribed dose to the PTV, whilst reducing the dose to the OAR, in comparison with 3D CRT in patients with prosthetic hip receiving radical radiotherapy for prostate cancer, potentially reducing the acute and late sideeffects of radiotherapy. 1016 poster FOCAL SALVAGE FOR PROSTATE CANCER RECURRENCES. M. Peters1 , M. Moman1 , U. van der Heide1 , M. Moerland1 , S. Franken1 , J. J. Battermann1 , M. van Deursen1 , M. van Vulpen1 1 U.M.C. U TRECHT, Utrecht, Netherlands Purpose: Recurrent prostate cancer after previous radiotherapy can be treated with a salvage treatment of the entire prostate. Data from salvage prostatectomy, salvage cryotherapy or salvage brachytherapy series show high rates of severe (grade 3 or higher) toxicity, even up to 30%. This causes the urology community to be reluctant with regard to salvage treatments to the entire prostate. Currently, Dynamic-Contrast Enhanced (DCE-)MRI allows localization of the recurrence within the prostate and thus enables focal salvage. We hypothesize severe toxicity rates will be significantly reduced by using focal salvage. Materials: In 16 patients with biopsy proven local recurrent prostate cancer focal salvage was performed by I-125 brachytherapy. Recurrences were located by DCE-MRI and confirmed by a 12-core biopsy scheme. Prescription dose to the recurrence was 144Gy, GEC-ESTRO guidelines with regard to sparing of rectum and bladder were met. Toxicity was recorded using the Common Toxicity Criteria (CTC) and quality of life was measured using Rand36, EORTC-C30 and-PR25. Results: With a minimum follow-up of six months, grade 3 gastro-intestinal toxicity was observed in only 1 patient. Quality of life was not impaired. Conclusions: Based on these preliminary data we conclude focal salvage seemed to be technically and clinically feasible, with an acceptable toxicity rate. 1017 poster GENITOURINARY TOXICITY IN PROSTATE HDR BRACHYTHERAPY E. Aleknavicius1 , A. Burneckis1 , A. Ivanauskas1 1 I NSTITUTE OF O NCOLOGY V ILNIUS U NIVERSITY, Clinic for Radiation Therapy, Vilnius, Lithuania Purpose: In Vilnius University Oncology Institute we started to perform HDR (high dose rate) prostate brachytherapy technique in combination with 3 D conformal external radiotherapy for high and intermediate prostate cancer patients in 2009-07. We treated 16 pts. until 2010-12. The follow-up of these patients was performed. The main purposes were to determine: acute genitourinary (GU) and gastrointestinal side effects and toxicities, PSA value dynamics Materials: We performed combined modality (CM) treatment using brachytherapy machine Varisource 200 with Iridium 195 (125Ir) source for brachytherapy and Varian linear accelerator for external beam therapy. The prescribed BT dose was 9,5Gy (26 izoGy) to the prostate and basis of seminal vesicals and after 10-14 days EBRT 50 Gy to the prostate and whole seminal vesicals and regional lymph nodes (if lymph node irradiation was needed. Treated pts. were: cT2b cT3b, Gleason score 6-7 and initial PSA value 4,13 50 ng/ml (intermediate and high risk group prostate cancer patients), median age 56 years. The prostate volume 22 46 ml. 14 of these patients received neoadjuvant antiandrogen hormonal treatment (1 12 moths).