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Alvaro Martinez - One of the best experts on this subject based on the ideXlab platform.
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conformal high dose rate Iridium 192 boost brachytherapy in locally advanced prostate cancer superior prostate specific antigen response compared with external beam treatment
The cancer journal from Scientific American, 1997Co-Authors: Jannifer S Stromberg, Alvaro Martinez, D Brabbins, Eric M Horwitz, Gary S Gustafson, Jose Gonzalez, William Spencer, Carl F Dmuchowski, Jay B Hollander, Frank A ViciniAbstract:Purpose Prostate-specific antigen levels are used to judge disease control of prostate cancer. No published data attest to the greater ability of conformal brachytherapy to control disease compared with conventional radiation at a single institution. This report compares the biochemical response rates in patients with stages T2b to T3c prostate cancer treated with conformal brachytherapy boost and external beam radiation with the rates in patients treated with conventional external radiation alone. Materials and methods From November 1991 through November 1995, 58 patients received 45.6 Gy pelvic external irradiation and three high dose rate Iridium-192 conformal boost implants of 5.5 to 6.5 Gy each. They were compared with 278 similarly staged patients treated from January 1987 through December 1991 with external beam radiation to prostate-only fields (median dose 66.6 Gy). No patient received androgen deprivation. Patient outcome was analyzed for biochemical control. Biochemical failure was defined as a prostate-specific antigen level > 1.5 ng/mL and rising on two consecutive values. If serial posttreatment prostate-specific antigen levels were showing a continuous downward trend, failure was not scored. Results Median follow-up was 43 months for the conventionally treated group and 26 months for the brachytherapy boost group. The median pretreatment prostate-specific antigen level was 14.3 ng/mL for the external-beam-radiation-alone group and 14.0 ng/mL for the brachytherapy boost group. The median Gleason scores were 6 and 7, respectively, for the two groups. The biochemical control rate was significantly higher in the brachytherapy boost treatment group. Three-year actuarial biochemical control rates were 85% versus 52% for the conformally and conventionally treated patients, respectively. In a multivariate analysis, the use of conformal brachytherapy boost and pretreatment prostate-specific antigen level were significant prognostic determinants of biochemical control. The 3-year actuarial rates of biochemical control for conformally versus conventionally treated patients, respectively, were 83% versus 72% for a pretreatment prostate-specific antigen level of 4.1 to 10.0 ng/mL, 85% versus 47% for a prostate-specific antigen level of 10.1 to 20.0 ng/mL, and 89% versus 29% for prostate-specific antigen > 20 ng/mL. When the analysis was limited to patients in both groups with a minimum 12-month follow-up, the brachytherapy boost group continued to show a higher biochemical control rate compared with the conventional radiation group (3-year actuarial rates of 86% vs 53%). Discussion These preliminary results show a significant improvement in the biochemical response rate with conformal boost brachytherapy and pelvic external radiation compared with conventional radiation alone. These results, coupled with our previously reported acceptable toxicity rates, support the use of this technique.
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improved local control and survival for surgically staged patients with locally advanced prostate cancer treated with up front low dose rate Iridium 192 prostate implantation and external beam irradiation
International Journal of Radiation Oncology Biology Physics, 1994Co-Authors: Jannifer S Stromberg, Gregory K Edmundson, Alvaro Martinez, Mark F Schray, Ralph C Benson, Graciela R Garton, Ananias C Diokno, Jose Lopez Gonzalez, Horst Zincke, D BrabbinsAbstract:Purpose: In an effort to improve upon the historically poor local control and survival rates for locally advanced prostate carcinoma, a prospective multidisciplinary clinical trial was initiated using low dose rate Iridium-192 prostate implantation and external beam irradiation. Methods and Materials: Between January 1983 and September 1989, 57 patients with newly diagnosed bulky prostatic carcinoma (5 Stage B2, 52 Stage C) were treated at the Mayo Clinic (34 patients) and William Beaumont Hospital (23 patients) with (a) 5 Gy delivered preoperatively in one fraction, (b) pelvic lymphadenectomy with interstitial implantation of the prostate using Iridium-192 seeds via a perineal template to 30–35 Gy, and (c) 30.6 Gy external irradiation to prostate only in 17 fractions. Results: After lymphadenectomy, 3057 (53%) patients had pathologically confirmed positive lymph nodes or “D1” disease. Thirty-four patients (60%) had Gleason scores ≥ 7. Mean age at diagnosis was 63.3 years. Median overall follow-up was 72 months. The 5-year actuarial survival rate was 85% and disease-free survival was 63%. The 5-year survival for patients with negative nodes was 93% and with positive nodes was 79%. The corresponding survival for patients with Gleason scores ≤ 6 was 96% and ≥ 7 was 78%. Multivariate analysis demonstrated that of all covariates considered, only Gleason score had prognostic significance for disease-free survival (p < 0.05) and no covariates were statistically significant for overall survival. Thirty-nine of the 57 patients had a prostatic rebiopsy performed at 18 months. Pathologically confirmed local control was ultimately achieved in 3139 (79.5%). There was no difference in survival in patients with positive rebiopsies vs. those with negative results. The 5-year actuarial rate of clinical local control was 94%. Three patients clinically failed locally and 21 demonstrated distant progression. The median time to progression was 34 months. Nineteen percent received some form of hormonal manipulation at the time of their treatment course and an additional 42% were treated with hormones during their follow-up period, primarily after distant failure. The grade 4 rectal ulceration rate decreased to 4.5% with modification of the brachytherapy technique. Three patients experienced grade 4 urinary incontinence and three patients experienced grades 3 or 4 chronic perineal pain. Conclusion: These results indicate that bulky prostate carcinoma can be successfully controlled locally by this novel and aggressive approach with moderate toxicity and improved survival.
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the use of iodine 125 seeds as a substitute for Iridium 192 seeds in temporary interstitial breast implants
International Journal of Radiation Oncology Biology Physics, 1992Co-Authors: Frank A Vicini, Julia White, G Gustafson, Richard C Matter, Daniel H Clarke, Gregory K Edmundson, Alvaro MartinezAbstract:Abstract Purpose: We have previously reported that the use of iodine-125 seeds in temporary plastic tube interstitial implants may be more advantageous than Iridium-192 seeds due to less patient and personnel radiation exposure, reduced shielding requirements, and significant dosimetric advantages. The impact of this isotope on the rate of local control and cosmetic outcome in patients with early stage breast cancer treated with interstitial implants for their irradiation "boost" remains to be defined. Methods and Materials: We reviewed the treatment outcome of 402 consecutive cases of Stage I and II breast cancer undergoing breast conserving therapy between 1/1/80 and 12/31/87. All patients underwent excisional biopsy and received 45–50 Gy to the entire breast followed by a boost to the tumor bed using either electrons (104 patients), photons (15 patients), or an interstitial implant with either Iridium-192 (197 patients) or iodine-125 (86 patients) to at least 60 Gy. Iodine-125 implants were primarily performed in patients with significant risk factors for local recurrence (71%) or in patients with large breasts (17%). Local tumor control and cosmetic outcome were assessed and contrasted between patients boosted with each modality. Results: With a median follow-up of 59.3 months, 18 (4.5%) patients developed a recurrence of the tumor in the treated breast (4.4% 5-year actuarial rate). No statistically significant differences in the 5-year actuarial rate of local recurrence were noted between patients boosted with either iodine-125 (3.0%), Iridium-192 (3.8%), electrons (5.4%), or photons (0%). Likewise, no significant differences in the percentage of patients obtaining good/excellent cosmetic results were noted between iodine-125 (93%), Iridium-192 (88%), electrons (90%), or photons (82%). Conclusion: We conclude that patients with Stage I and II breast cancer undergoing breast conserving therapy and judged to be candidates for boosts with interstitial implants can be effectively treated with iodine-125 seeds. Use of this isotope results in less patient and personnel irradiation exposure and a better dose distribution than Iridium-192, since dose optimization can be routinely employed. Overall, local control and cosmetic outcome have been excellent and are similar to either Iridium-192, electrons, or photons.
Mikio Namiki - One of the best experts on this subject based on the ideXlab platform.
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Clinical Results of Iridium-192 High Dose Rate Brachytherapy with External Beam Radiotherapy
Japanese Journal of Clinical Oncology, 2010Co-Authors: Takahiro Nohara, Kadono Yoshifumi, Kitagawa Yasuhide, Kazuyoshi Shigehara, Kouji Izumi, Hiroyuki Konaka, Kazutaka Narimoto, Tomoyasu Kumano, Atsushi Mizokami, Mikio NamikiAbstract:Objective: Here, we report the clinical results of Iridium-192 high dose rate brachytherapy at Kanazawa University Hospital. Methods: The study population consisted of 166 patients diagnosed with T1c-T3bN0M0 prostate cancer treated with high dose rate brachytherapy and external beam radiotherapy and followed up for 6 months or longer. Treatment consisted of external beam radiotherapy to the prostate at 44 Gy/22 fractions and high dose rate brachytherapy at 18 Gy/3 fractions. Results: Median follow-up interval was 31.5 months (range 6.2-88.7). The overall 5-year biological recurrence-free survival rate was 93.0%. The 5-year biological recurrence-free survival rates for the patients in low-, intermediate- and high-risk groups according to the D'Amico risk classification criteria were 96.1%, 89.0% and 91.6%, respectively. When limited to the group that did not receive adjuvant hormonal therapy, the 5-year biological recurrence-free survival rates for the patients in low-, intermediate- and high-risk groups were 96.0%, 96.3% and 82.9%, respectively. Grade 3 or greater adverse effects were rare. Urethral stricture was observed in only 1.0% of the patients. Eighty percent of patients retained erectile function after high dose rate brachytherapy and reported satisfaction with sexual function. Conclusions: High dose rate brachytherapy is considered a good form of treatment for localized prostate cancer, although longer follow-up is necessary.
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four year clinical statistics of Iridium 192 high dose rate brachytherapy
International Journal of Urology, 2006Co-Authors: Kazuyoshi Shigehara, Atsushi Mizokami, Kazuto Komatsu, Kiyoshi Koshida, Mikio NamikiAbstract:Background: We evaluated the efficacy and complications of high dose rate (HDR) brachytherapy using Iridium-192 (192Ir) combined with external beam radiotherapy (EBRT) in patients with prostate cancer. Methods: Ninety-seven patients underwent 192Ir HDR brachytherapy combined with EBRT at our institution between February 1999 and December 2003. Of these, 84 patients were analysed in the present study. 192Ir was delivered three times over a period of 2 days, 6 Gy per time, for a total dose of 18 Gy. Interstitial application was followed by EBRT at a dose of 44 Gy. Progression was defined as three consecutive prostate-specific antigen (PSA) rises after a nadir according to the American Society for Therapeutic Radiology and Oncology criteria. The results were classified into those for all patients and for patients who did not undergo adjuvant hormone therapy. Results: The 4-year overall survival of all patients, the nonadjuvant hormone therapy group (NAHT) and the adjuvant hormone therapy group (AHT) was 87.2%, 100%, and 70.1%, respectively. The PSA progression-free survival rate of all patients, NAHT, and AHT was 82.6%, 92.0%, and 66.6%, respectively. Of all patients, the 4-year PSA progression-free survival rates of PSA < 20 and PSA ≥ 20 groups were 100%, and 46.8%, respectively. According to the T stage classification, PSA progression-free survival rates of T1c, T2, T3, and T4 were 100%, 82.8%, 100%, and 12.1%, respectively. Prostate-specific antigen progression-free survival rates of groups with Gleason scores (GS) < 7 and GS ≥ 7 were 92.8% and 60.1%, respectively. Of NAHT, PSA progression-free survival of PSA < 20 was 100% vs 46.8% for PSA ≥ 20, that of T1c was 100% vs 75% for T2, and that of GS < 7 was 100% vs 75% for GS ≥ 7. No significant intraoperative or postoperative complications requiring urgent treatment occurred except cerebellum infarction. Conclusions: 192Ir HDR brachytherapy combined with EBRT was as effective as radical prostatectomy and had few associated complications.
Gregory K Edmundson - One of the best experts on this subject based on the ideXlab platform.
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improved local control and survival for surgically staged patients with locally advanced prostate cancer treated with up front low dose rate Iridium 192 prostate implantation and external beam irradiation
International Journal of Radiation Oncology Biology Physics, 1994Co-Authors: Jannifer S Stromberg, Gregory K Edmundson, Alvaro Martinez, Mark F Schray, Ralph C Benson, Graciela R Garton, Ananias C Diokno, Jose Lopez Gonzalez, Horst Zincke, D BrabbinsAbstract:Purpose: In an effort to improve upon the historically poor local control and survival rates for locally advanced prostate carcinoma, a prospective multidisciplinary clinical trial was initiated using low dose rate Iridium-192 prostate implantation and external beam irradiation. Methods and Materials: Between January 1983 and September 1989, 57 patients with newly diagnosed bulky prostatic carcinoma (5 Stage B2, 52 Stage C) were treated at the Mayo Clinic (34 patients) and William Beaumont Hospital (23 patients) with (a) 5 Gy delivered preoperatively in one fraction, (b) pelvic lymphadenectomy with interstitial implantation of the prostate using Iridium-192 seeds via a perineal template to 30–35 Gy, and (c) 30.6 Gy external irradiation to prostate only in 17 fractions. Results: After lymphadenectomy, 3057 (53%) patients had pathologically confirmed positive lymph nodes or “D1” disease. Thirty-four patients (60%) had Gleason scores ≥ 7. Mean age at diagnosis was 63.3 years. Median overall follow-up was 72 months. The 5-year actuarial survival rate was 85% and disease-free survival was 63%. The 5-year survival for patients with negative nodes was 93% and with positive nodes was 79%. The corresponding survival for patients with Gleason scores ≤ 6 was 96% and ≥ 7 was 78%. Multivariate analysis demonstrated that of all covariates considered, only Gleason score had prognostic significance for disease-free survival (p < 0.05) and no covariates were statistically significant for overall survival. Thirty-nine of the 57 patients had a prostatic rebiopsy performed at 18 months. Pathologically confirmed local control was ultimately achieved in 3139 (79.5%). There was no difference in survival in patients with positive rebiopsies vs. those with negative results. The 5-year actuarial rate of clinical local control was 94%. Three patients clinically failed locally and 21 demonstrated distant progression. The median time to progression was 34 months. Nineteen percent received some form of hormonal manipulation at the time of their treatment course and an additional 42% were treated with hormones during their follow-up period, primarily after distant failure. The grade 4 rectal ulceration rate decreased to 4.5% with modification of the brachytherapy technique. Three patients experienced grade 4 urinary incontinence and three patients experienced grades 3 or 4 chronic perineal pain. Conclusion: These results indicate that bulky prostate carcinoma can be successfully controlled locally by this novel and aggressive approach with moderate toxicity and improved survival.
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the use of iodine 125 seeds as a substitute for Iridium 192 seeds in temporary interstitial breast implants
International Journal of Radiation Oncology Biology Physics, 1992Co-Authors: Frank A Vicini, Julia White, G Gustafson, Richard C Matter, Daniel H Clarke, Gregory K Edmundson, Alvaro MartinezAbstract:Abstract Purpose: We have previously reported that the use of iodine-125 seeds in temporary plastic tube interstitial implants may be more advantageous than Iridium-192 seeds due to less patient and personnel radiation exposure, reduced shielding requirements, and significant dosimetric advantages. The impact of this isotope on the rate of local control and cosmetic outcome in patients with early stage breast cancer treated with interstitial implants for their irradiation "boost" remains to be defined. Methods and Materials: We reviewed the treatment outcome of 402 consecutive cases of Stage I and II breast cancer undergoing breast conserving therapy between 1/1/80 and 12/31/87. All patients underwent excisional biopsy and received 45–50 Gy to the entire breast followed by a boost to the tumor bed using either electrons (104 patients), photons (15 patients), or an interstitial implant with either Iridium-192 (197 patients) or iodine-125 (86 patients) to at least 60 Gy. Iodine-125 implants were primarily performed in patients with significant risk factors for local recurrence (71%) or in patients with large breasts (17%). Local tumor control and cosmetic outcome were assessed and contrasted between patients boosted with each modality. Results: With a median follow-up of 59.3 months, 18 (4.5%) patients developed a recurrence of the tumor in the treated breast (4.4% 5-year actuarial rate). No statistically significant differences in the 5-year actuarial rate of local recurrence were noted between patients boosted with either iodine-125 (3.0%), Iridium-192 (3.8%), electrons (5.4%), or photons (0%). Likewise, no significant differences in the percentage of patients obtaining good/excellent cosmetic results were noted between iodine-125 (93%), Iridium-192 (88%), electrons (90%), or photons (82%). Conclusion: We conclude that patients with Stage I and II breast cancer undergoing breast conserving therapy and judged to be candidates for boosts with interstitial implants can be effectively treated with iodine-125 seeds. Use of this isotope results in less patient and personnel irradiation exposure and a better dose distribution than Iridium-192, since dose optimization can be routinely employed. Overall, local control and cosmetic outcome have been excellent and are similar to either Iridium-192, electrons, or photons.
K A Dinshaw - One of the best experts on this subject based on the ideXlab platform.
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transperineal low dose rate Iridium 192 interstitial brachytherapy in cervical carcinoma stage iib
Strahlentherapie Und Onkologie, 2001Co-Authors: Ashwini Budrukkar, Shyam Kishore Shrivastava, Rakesh Jalali, Jai Prakash Agarwal, Deepak Dattatraya Deshpande, R M Nehru, K A DinshawAbstract:To assess local control, survival and complications in patients with cervical carcinoma Stage IIB treated radically with transperineal Iridium-192 low-dose rate interstitial brachytherapy following external beam radiotherapy. Patients and Methods: 65 women (age 25–70 years, mean 47 years) with cervical carcinoma Stage IIB were initially treated with external beam radiotherapy on a telecobalt or 6 MV linear accelerator to a dose of 50 Gy delivered in 5–6 weeks. After 2–3 weeks of completing external radiation, patients received interstitial brachytherapy with Iridium-192 (acivity 0.5–1 mCi/cm) using a Syed-Neblett perineal template. The median dose delivered to the implant volume was 24 Gy (range 20–32 Gy) delivered at an average dose rate of 0.70 Gy/h (range 0.40–1.20 Gy/h). A point defined at 1.5 cm lateral to the central uterine tandem at the level of os was taken as a representative for assessing the dose to the cervix. Mean doses delivered by interstitial brachytherapy to point A, cervix, point B and rectum were 38 Gy, 34 Gy, 16 Gy and 16, Gy, respectively. Results: At a median follow-up of 53 months, the actuarial disease free survival and overall survival for 65 patients at both 5 and 10 years was 64% and 44%, respectively. Response to radiotherapy was a strong predictor of local control with 82% of patients continuing to have pelvic control after initial complete response. Overall, nine (14%) patients had persistent disease, ten (15%) developed a central recurrence after initial control and three patients developed distant metastasis on follow-up. No patient had any immediate treatment-related complication. Late toxicity included grade I–II rectal reactions in five patients and grade IV bladder complication (vesico-vaginal fistula) in two patients. 5 years after treatment, one patient developed intestinal obstruction, which was relieved after conservative management. Two patients developed vaginal stenosis. The 5- and 10-year disease free survival was 48% in patients aged less than 45 years as compared to 80% in patients of more than 45 years (p = 0.009). Dose to the cervical point was a prognostic indicator with 5- and 10-year disease free survival of 47% in patients who received 35 Gy (p = 0.03). There was no difference in local control and survival in patients with minimal and moderate parametrial involvement. Bulky disease (> 4 cm) at presentation and a longer gap between external radiation and brachytherapy showed a trend towards inferior local control. Conclusions: Interstitial brachytherapy after external beam irradiation in patients with cervical carcinoma Stage IIB results in acceptable local control, survival and complication rates. Increased dose to the cervical disease results in improved local control and survival and should therefore be considered while optimizing brachytherapy treatment plans. Comparison of the results with those of standard intracavitary therapy remains to be proven in a randomized trial.
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influence of dose rate and dose per fraction on clinical outcome of breast cancer treated by external beam irradiation plus Iridium 192 implants analysis of 289 cases
International Journal of Radiation Oncology Biology Physics, 1993Co-Authors: S M Deore, K A Dinshaw, Rajiv Sarin, S K ShrivastavaAbstract:Abstract Purpose : To study the influence of Iridium 192 implant dose-rate and dose per fraction of external irradiation on clinical outcome, the results in 289 patients with early breast cancer were analyzed retrospectively. Methods and Materials : From 1980 to 1990, 118 T, and 171 T2 lesions of breast were treated definitively by radiotherapy, following conservative surgery. External irradiation dose of 45 Gy was delivered either with 2.5 Gy or 1.8 Gy per fraction to the entire target volume, plus boost to the primary tumor. Boost dose of 15 to 30 Gy was given to the primary tumor either with Iridium-192 implants or electrons. The implant dose-rate varied between 20 cGy/hr to 160 cGy/hr. Result : The minimum follow-up was of 12 months and maximum of 11 years (median: 56 months). Out of 273 tumors boosted with implants, the 270 patients were divided into five groups according to dose-rate as, groups 1 (20–29 cGy/hr, n = 17), group 2 (30–49 cGy/hr, n = 144), group 3 (50–69 cGy/hr, n = 69), group 4 (70–99 cGy/hr, n = 27) and group 5 (100–160 cGy/hr, n = 13). The local failure rate was significantly increased in the group of patients treated with implant dose-rate 100 cGy/hr (p Conclusion : The present analysis indicate that the implant dose-rate should be maintained between 30–70 cGy/hr to maximize local control and reduce the late normal tissue injury. Also the increase in dose per fraction of external irradiation white not influencing local control rate was crucial for incidence of late complications and cosmetic outcome.
Don R Goffinet - One of the best experts on this subject based on the ideXlab platform.
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Iridium 192 interstitial implant and external beam radiation therapy in the management of squamous cell carcinomas of the tonsil and soft palate
International Journal of Radiation Oncology Biology Physics, 1994Co-Authors: Robert A Behar, Peter J Martin, Willard E Fee, Don R GoffinetAbstract:Abstract Purpose : To evaluate the results, techniques, indications and complications of interstitial brachytherapy in the management of squamous cell carcinomas of the tonsil and soft palate, we reviewed the Stanford University Medical School experience with this modality. Methods and Materials : Between May 1975 and January 1990, 37 patients with squamous cell carcinomas of the Tonsillo-Palatine region were treated with a combination of external beam irradiation and a removable Iridium-192 interstitial implant. The mean age of these patients was 56. Twenty-two were males and 15 were females. The stage distribution included four patients with Stage I, 5 with Stage II, 10 with Stage III, and 18 with Stage IV cancers. Thirty-two percent ( 12 37 ) of these patients had T3 or T4 lesions. Forty-nine percent ( 18 37 ) had stage N2 or N3 cervical lymphadenopathy. All 37 patients received initial external beam irradiation to the primary, bilateral necks, and supraclavicular region (mean dose: 5400 cGy, range 4000–6600). Eighteen patients (49%) also received neck dissections. All 37 patients received an interstitial Irridium-192 implant using a combination intraoral swage and external looping technique. The mean dose was 2700 cGy (range 2000–4000 cGy) to an average volume of 24 cc (range 5–81). Results : Local control was obtained in 95% ( 35 37 ) of the patients. Eighty-seven percent ( 32 37 ) of the patients have remained disease-free in the neck. Nine patients have developed second primary lesions, and one developed pulmonary metastasis. Fifteen patients have died (6 succumbed to their cancers, 6 to second primaries, 2 to inter-current disease, 1 from an unknown cause). The actuarial freedom from relapse is 75%, and overall survival is 64% at 5 years, with a mean follow up of 43 months (range 5–110). Complications were limited to one case of osteo-radionecrosis of the mandible and one tonsillar ulcer. Functional and esthetic integrity was preserved in most of these patients. Conclusion : Iridium-192 interstitial implant boost combined with external beam radiation therapy is a safe and effective therapy in the management of locally advanced carcinomas of the tonsil and soft palate.
