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Research paper thumbnail of High-dose rate brachytherapy boost for prostate cancer: Outcomes and genitourinary toxicity

Brachytherapy, 2015

To report disease outcomes and late urinary toxicity profile. To assess the impact of changing te... more To report disease outcomes and late urinary toxicity profile. To assess the impact of changing technique and evolving quality assurance on genitourinary toxicity rates. One hundred eighty patients were treated with external beam radiation therapy and high dose rate brachytherapy (HDRB) for localized intermediate- and high-risk prostate cancer, between December 2002 and February 2012. The HDRB technique evolved over the period of this study, from 19.5 Gy/3 (n = 68), to 17 Gy/2 (n = 40), 18 Gy/2 (n = 39), and most recently 19 Gy/2 (n = 33). In the two fraction cohort, 68 patients underwent additional correction for catheter displacement before each fraction. With a median followup of 5.2 years, 5-year freedom from failure was 93.7% for intermediate, and 76.0% for high risk patients. The 3- and 6-year cumulative stricture incidence for all patients was 7.8% and 15.3%, respectively. There was no statistically significant difference in stricture rate for the four dose levels used nor between the three fractions and the two fraction technique overall. The 19 Gy/2 fractionation group had the lowest 3-year stricture rate (3.0%). The addition of correction for intrafraction catheter displacement did not result in a statistically significant difference in stricture rates, although the severity of strictures has been reduced. Our biochemical control is consistent with other similar series. We found no increase in late urinary toxicity with a two fraction, two implant HDRB technique compared with three fractions. The HDRB dose did not correlate with stricture rates in our series. Correction of intra-fraction catheter displacement did not lead to a statistically significant reduction in stricture rates, although may have mitigated the effects of dose escalation.

Research paper thumbnail of Prostate HDR brachytherapy catheter displacement between planning and treatment delivery

Radiotherapy and Oncology, 2011

Background and purpose: HDR brachytherapy is used as a conformal boost for treating prostate canc... more Background and purpose: HDR brachytherapy is used as a conformal boost for treating prostate cancer. Given the large doses delivered, it is critical that the volume treated matches that planned. Our outpatient protocol comprises two 9 Gy fractions, two weeks apart. We prospectively assessed catheter displacement between CT planning and treatment delivery. Materials and methods: Three fiducial markers and the catheters were implanted under transrectal ultrasound guidance. Metal marker wires were inserted into 4 reference catheters before CT; marker positions relative to each other and to the marker wires were measured from the CT scout. Measurements were repeated immediately prior to treatment delivery using pelvic X-ray with marker wires in the same reference catheters. Measurements from CT scout and film were compared. For displacements of 5 mm or more, indexer positions were adjusted prior to treatment delivery. Results: Results are based on 48 implants, in 25 patients. Median time from planning CT to treatment delivery was 254 min (range 81-367 min). Median catheter displacement was 7.5 mm (range À2.9-23.9 mm), 67% of implants had displacement of 5 mm or greater. Displacements were predominantly caudal. Conclusions: Catheter displacement can occur in the 1-3 h between the planning CT scan and treatment. It is recommended that departments performing HDR prostate brachytherapy verify catheter positions immediately prior to treatment delivery.

Research paper thumbnail of HDR brachytherapy combined with external beam radiation for localised prostate cancer: Early experience from the Sydney Cancer Centre

Journal of Medical Imaging and Radiation Oncology, 2012

Introduction: To report the toxicity and early efficacy of high-dose rate brachytherapy (HDR) as ... more Introduction: To report the toxicity and early efficacy of high-dose rate brachytherapy (HDR) as a boost to external beam radiation (EBRT) in the treatment of localised prostate cancer. Methods: Between December 2002 and November 2007, 101 consecutive patients with intermediate or high risk prostate cancer were treated with EBRT plus an HDR boost. The HDR boost was initially delivered in three fractions of 6.5 Gy each via one implant; this was subsequently modified to a two-fraction technique with separate implants 2 weeks apart (8.5 Gy each). Most patients also received at least 3 months of androgen ablation. Results: Our cohort included 65 intermediate risk and 36 high-risk patients. Sixty-seven patients received the three-fraction regime; 34 the two-fraction schedule. Median follow-up was 56 months, at which time 82% of patients were free from failure. The 4-year disease-free survival for intermediate and high-risk groups was 95% and 66%, respectively (overall 85%). Significant acute toxicities included clot retention (eight patients), one traumatic urethral injury, one case of retention requiring suprapubic catheter placement, one case of new onset atrial fibrillation and three cases of pulmonary emboli. At 4 years, the rate of late grade 2 genitourinary toxicity was 8%; two patients experienced grade 3 toxicity. No late grade 3 gastrointestinal toxicity was observed. Potency was preserved in 72% of those patients reporting normal pre-treatment sexual function. Conclusions: Our cohort experienced toxicity similar to previously published HDR boost series with very promising early efficacy results.

Research paper thumbnail of A comparison of post-implant US/CT image fusion and MRI/CT image fusion for 125I prostate brachytherapy post implant dosimetry

Brachytherapy, 2009

Brachytherapy, Volume 8, Issue 2, Pages 124, April 2009, Authors:Nitya Patanjali, MBBS, FRANZCR; ... more Brachytherapy, Volume 8, Issue 2, Pages 124, April 2009, Authors:Nitya Patanjali, MBBS, FRANZCR; Mira Keyes, MD; W. James Morris, MD; Mitchell Liu, MD; Robert Harrison; Ingrid Spadinger, Ph.D.; Veronika Moravan. ...

Research paper thumbnail of Patient-reported outcomes of prostate high-dose-rate brachytherapy boost comparing an outpatient and inpatient protocol: A two-center chronologic cohort study

Brachytherapy, 2011

To determine patients&amp... more To determine patients' self-reported experiences of outpatient high-dose-rate prostate brachytherapy boost, and compare with previous cohort treated as inpatients. Using the Prostate Brachytherapy Questionnaire, we previously examined patients' subjective experience of the brachytherapy procedure when it involved one implant and hospitalization with the template in situ for 2 days (Group 1). The protocol was subsequently changed to two implants, 2 weeks apart as outpatients. Fifty-eight patients treated with the new protocol (Group 2) completed the same questionnaire. We compared the self-reported experiences between Groups 1 and 2 and also between the first and second implant for those in Group 2. Our hypothesis was that the worst rated issues in Group 1 might be reduced with the new approach. Group 2 patients were less troubled overall by the procedure (mean scores 2.3 vs. 3.2, p=0.0293). Specifically, they were less troubled by "discomfort" (2.8 vs. 3.8, p=0.0254); "being stuck in…

Research paper thumbnail of High-dose rate brachytherapy boost for prostate cancer: Outcomes and genitourinary toxicity

Brachytherapy, 2015

To report disease outcomes and late urinary toxicity profile. To assess the impact of changing te... more To report disease outcomes and late urinary toxicity profile. To assess the impact of changing technique and evolving quality assurance on genitourinary toxicity rates. One hundred eighty patients were treated with external beam radiation therapy and high dose rate brachytherapy (HDRB) for localized intermediate- and high-risk prostate cancer, between December 2002 and February 2012. The HDRB technique evolved over the period of this study, from 19.5 Gy/3 (n = 68), to 17 Gy/2 (n = 40), 18 Gy/2 (n = 39), and most recently 19 Gy/2 (n = 33). In the two fraction cohort, 68 patients underwent additional correction for catheter displacement before each fraction. With a median followup of 5.2 years, 5-year freedom from failure was 93.7% for intermediate, and 76.0% for high risk patients. The 3- and 6-year cumulative stricture incidence for all patients was 7.8% and 15.3%, respectively. There was no statistically significant difference in stricture rate for the four dose levels used nor between the three fractions and the two fraction technique overall. The 19 Gy/2 fractionation group had the lowest 3-year stricture rate (3.0%). The addition of correction for intrafraction catheter displacement did not result in a statistically significant difference in stricture rates, although the severity of strictures has been reduced. Our biochemical control is consistent with other similar series. We found no increase in late urinary toxicity with a two fraction, two implant HDRB technique compared with three fractions. The HDRB dose did not correlate with stricture rates in our series. Correction of intra-fraction catheter displacement did not lead to a statistically significant reduction in stricture rates, although may have mitigated the effects of dose escalation.

Research paper thumbnail of Prostate HDR brachytherapy catheter displacement between planning and treatment delivery

Radiotherapy and Oncology, 2011

Background and purpose: HDR brachytherapy is used as a conformal boost for treating prostate canc... more Background and purpose: HDR brachytherapy is used as a conformal boost for treating prostate cancer. Given the large doses delivered, it is critical that the volume treated matches that planned. Our outpatient protocol comprises two 9 Gy fractions, two weeks apart. We prospectively assessed catheter displacement between CT planning and treatment delivery. Materials and methods: Three fiducial markers and the catheters were implanted under transrectal ultrasound guidance. Metal marker wires were inserted into 4 reference catheters before CT; marker positions relative to each other and to the marker wires were measured from the CT scout. Measurements were repeated immediately prior to treatment delivery using pelvic X-ray with marker wires in the same reference catheters. Measurements from CT scout and film were compared. For displacements of 5 mm or more, indexer positions were adjusted prior to treatment delivery. Results: Results are based on 48 implants, in 25 patients. Median time from planning CT to treatment delivery was 254 min (range 81-367 min). Median catheter displacement was 7.5 mm (range À2.9-23.9 mm), 67% of implants had displacement of 5 mm or greater. Displacements were predominantly caudal. Conclusions: Catheter displacement can occur in the 1-3 h between the planning CT scan and treatment. It is recommended that departments performing HDR prostate brachytherapy verify catheter positions immediately prior to treatment delivery.

Research paper thumbnail of HDR brachytherapy combined with external beam radiation for localised prostate cancer: Early experience from the Sydney Cancer Centre

Journal of Medical Imaging and Radiation Oncology, 2012

Introduction: To report the toxicity and early efficacy of high-dose rate brachytherapy (HDR) as ... more Introduction: To report the toxicity and early efficacy of high-dose rate brachytherapy (HDR) as a boost to external beam radiation (EBRT) in the treatment of localised prostate cancer. Methods: Between December 2002 and November 2007, 101 consecutive patients with intermediate or high risk prostate cancer were treated with EBRT plus an HDR boost. The HDR boost was initially delivered in three fractions of 6.5 Gy each via one implant; this was subsequently modified to a two-fraction technique with separate implants 2 weeks apart (8.5 Gy each). Most patients also received at least 3 months of androgen ablation. Results: Our cohort included 65 intermediate risk and 36 high-risk patients. Sixty-seven patients received the three-fraction regime; 34 the two-fraction schedule. Median follow-up was 56 months, at which time 82% of patients were free from failure. The 4-year disease-free survival for intermediate and high-risk groups was 95% and 66%, respectively (overall 85%). Significant acute toxicities included clot retention (eight patients), one traumatic urethral injury, one case of retention requiring suprapubic catheter placement, one case of new onset atrial fibrillation and three cases of pulmonary emboli. At 4 years, the rate of late grade 2 genitourinary toxicity was 8%; two patients experienced grade 3 toxicity. No late grade 3 gastrointestinal toxicity was observed. Potency was preserved in 72% of those patients reporting normal pre-treatment sexual function. Conclusions: Our cohort experienced toxicity similar to previously published HDR boost series with very promising early efficacy results.

Research paper thumbnail of A comparison of post-implant US/CT image fusion and MRI/CT image fusion for 125I prostate brachytherapy post implant dosimetry

Brachytherapy, 2009

Brachytherapy, Volume 8, Issue 2, Pages 124, April 2009, Authors:Nitya Patanjali, MBBS, FRANZCR; ... more Brachytherapy, Volume 8, Issue 2, Pages 124, April 2009, Authors:Nitya Patanjali, MBBS, FRANZCR; Mira Keyes, MD; W. James Morris, MD; Mitchell Liu, MD; Robert Harrison; Ingrid Spadinger, Ph.D.; Veronika Moravan. ...

Research paper thumbnail of Patient-reported outcomes of prostate high-dose-rate brachytherapy boost comparing an outpatient and inpatient protocol: A two-center chronologic cohort study

Brachytherapy, 2011

To determine patients&amp... more To determine patients' self-reported experiences of outpatient high-dose-rate prostate brachytherapy boost, and compare with previous cohort treated as inpatients. Using the Prostate Brachytherapy Questionnaire, we previously examined patients' subjective experience of the brachytherapy procedure when it involved one implant and hospitalization with the template in situ for 2 days (Group 1). The protocol was subsequently changed to two implants, 2 weeks apart as outpatients. Fifty-eight patients treated with the new protocol (Group 2) completed the same questionnaire. We compared the self-reported experiences between Groups 1 and 2 and also between the first and second implant for those in Group 2. Our hypothesis was that the worst rated issues in Group 1 might be reduced with the new approach. Group 2 patients were less troubled overall by the procedure (mean scores 2.3 vs. 3.2, p=0.0293). Specifically, they were less troubled by "discomfort" (2.8 vs. 3.8, p=0.0254); "being stuck in…