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1.
Brachytherapy ; 19(6): 762-766, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32952055

RESUMO

PURPOSE: Safe delivery of brachytherapy and establishing a safety culture are critical in high-quality brachytherapy. The American Brachytherapy Society (ABS) Quality and Safety Committee surveyed members regarding brachytherapy services offered, safety practices during treatment, quality assurance procedures, and needs to develop safety and training materials. METHODS AND MATERIALS: A 22-item survey was sent to ABS membership in early 2019 to physicians, physicists, therapists, nurses, and administrators. Participation was voluntary. Responses were summarized with descriptive statistics and relative frequency distributions. RESULTS: There were 103 unique responses. Approximately one in three was attending physicians and one in three attending physicists. Most were in practice >10 years. A total of 94% and 50% performed gynecologic and prostate brachytherapy, respectively. Ninety-one percent performed two-identification patient verification before treatment. Eighty-six percent performed a time-out. Ninety-five percent had an incident reporting or learning system, but only 71% regularly reviewed incidents. Half reviewed safety practices within the last year. Twenty percent reported they were somewhat or not satisfied with department safety culture, but 92% of respondents were interested in improving safety culture. Most reported time, communication, and staffing as barriers to improving safety. Most respondents desired safety-oriented webinars, self-assessment modules, learning modules, or checklists endorsed by the ABS to improve safety practice. CONCLUSIONS: Most but not all practices use standards and quality assurance procedures in line with society recommendations. There is a need to heighten safety culture at many departments and to shift resources (e.g., time or staffing) to improve safety practice. There is a desire for society guidance to improve brachytherapy safety practices. This is the first survey to assess safety practice patterns among a national sample of radiation oncologists with expertise in brachytherapy.

2.
J Am Acad Dermatol ; 2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32827607

RESUMO

BACKGROUND: Radiation therapy (RT) is a treatment option for selected skin cancers. The histologic effects of RT on normal skin or skin cancers are not well-characterized. Dermoscopy, high frequency ultrasonography (HFUS), and reflectance confocal microscopy (RCM) are non-invasive imaging modalities that may help characterize RT response. OBJECTIVES: To describe changes in the tumor and surrounding skin of basal cell carcinoma (BCC) patients treated with RT. METHODS: The study was conducted between 2014-2018. Patients with biopsy-proven BCCs were treated with 42 Gy in 6 fractions using a commercially available brachytherapy device. Dermoscopy, HFUS, RCM were performed before treatment, 6 weeks, 3 months and 12 months after RT. RESULTS: 137 imaging assessments (RCM + dermoscopy + HFUS) were performed in 12 patients. Presence of BCC-specific features were present in 81.8%, 91% and 17% of patients imaged with dermoscopy, RCM and HFUS at baseline, prior to treatment. After treatment, resolution of these features was noted in 33.4%, 91.7%, and 100% of patients imaged with the respective modalities. No recurrences were seen after 31.7 months mean follow-up. LIMITATIONS: Small sample size and no histopathological correlation. CONCLUSION: Dermoscopy and HFUS were not as reliable as RCM at characterizing BCCs RT response.

3.
Brachytherapy ; 19(4): 415-426, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32409128

RESUMO

PURPOSE: Keratinocyte carcinoma (KC, previously nonmelanoma skin cancer) represents the most common cancer worldwide. While surgical treatment is commonly utilized, various radiation therapy techniques are available including external beam and brachytherapy. As such, the American Brachytherapy Society has created an updated consensus statement regarding the use of brachytherapy in the treatment of KCs. METHODS: Physicians and physicists with expertise in skin cancer and brachytherapy created a consensus statement for appropriate patient selection, data, dosimetry, and utilization of skin brachytherapy and techniques based on a literature search and clinical experience. RESULTS: Guidelines for patient selection, evaluation, and dose/fractionation schedules to optimize outcomes for patients with KC undergoing brachytherapy are presented. Studies of electronic brachytherapy are emerging, although limited long-term data or comparative data are available. Radionuclide-based brachytherapy represents an appropriate option for patients with small KCs with multiple techniques available. CONCLUSIONS: Skin brachytherapy represents a standard of care option for appropriately selected patients with KC. Radionuclide-based brachytherapy represents a well-established technique; however, the current recommendation is that electronic brachytherapy be used for KC on prospective clinical trial or registry because of a paucity of mature data.

4.
Brachytherapy ; 18(3): 277-284, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30803923

RESUMO

BACKGROUND: Intraoperative radiotherapy (IORT) is an effective strategy for the delivery of high doses of radiotherapy to a residual tumor or resection cavity with relative sparing of nearby healthy tissues. This strategy is an important component of the multimodality management of pediatric soft tissue sarcomas, particularly in cases where patients have received prior courses of external beam radiotherapy. PURPOSE: Tumor beds with significant topographic irregularity remain a therapeutic challenge because existing IORT technologies are typically most reliable with flat surfaces. To address this limitation, we have developed a novel strategy to create custom, prefabricated high-dose-rate (HDR)-IORT applicators designed to match the shape of an anticipated surgical cavity. METHODS AND MATERIALS: Silastic applicators are constructed using three-dimensional (3D) printing and are derived from volumetric segmentation of preoperative imaging. RESULTS: HDR preplanning with the applicators improves dosimetric accuracy and minimizes incremental operative time. In this report, we describe the fabrication process for the 3D-printed applicators and detail our experience utilizing this strategy in two pediatric patients who underwent HDR-IORT as part of complex base of skull sarcoma resections. CONCLUSIONS: Early experience suggests that usage of the custom applicators is feasible, versatile for a variety of clinical situations, and enables the uniform delivery of high superficial doses of radiotherapy to irregularly shaped surgical cavities.


Assuntos
Braquiterapia/instrumentação , Desenho de Equipamento , Neoplasias/terapia , Braquiterapia/métodos , Criança , Feminino , Humanos , Período Intraoperatório , Masculino , Neoplasia Residual , Impressão Tridimensional , Planejamento da Radioterapia Assistida por Computador , Radioterapia Adjuvante
5.
Brachytherapy ; 18(3): 292-298, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30497939

RESUMO

PURPOSE: Brachytherapy is utilized in the treatment of many different malignancies; although traditionally performed with low-dose-rate or high-dose-rate techniques, more recently, electronic brachytherapy (EB) has emerged as a potential alternative. At this time, there are no evidence-based guidelines to assist clinicians in patient selection for EB and concerns exits regarding differences in dosimetry as compared to traditional brachytherapy techniques. As such, the American Brachytherapy Society appointed a group of physicians and physicists to create a consensus statement regarding the use of EB. METHODS AND MATERIALS: Physicians and physicists with expertise in brachytherapy created a site-directed consensus statement for appropriate patient selection and utilization of EB based on a literature search and clinical experience. RESULTS: EB has been utilized to deliver accelerated partial breast irradiation with, thus far acceptable local control and toxicity rates including a randomized trial that used EB to deliver intraoperative radiotherapy; however, prospective data with large patient numbers and long-term follow up are needed. Increasing numbers of patients have been treated with EB for nonmelanomatous skin cancers; although, preliminary data are promising, there is a lack of data comparing EB to traditional radiotherapy techniques as well as a lack of long-term follow up. For treatment of the vaginal cuff with EB, small retrospective studies have been reported without long-term follow up. CONCLUSIONS: In light of a randomized trial in breast showing higher rates of recurrence and the lack of prospective data with mature follow up with other sites, as well as concerns regarding dosimetry, it is not recommended that EB be utilized for accelerated partial breast irradiation, nonmelanomatous skin cancers, or vaginal cuff brachytherapy outside prospective clinical trials at this time.


Assuntos
Braquiterapia/métodos , Neoplasias da Mama/radioterapia , Neoplasias dos Genitais Femininos/radioterapia , Seleção de Pacientes , Neoplasias Cutâneas/radioterapia , Braquiterapia/efeitos adversos , Consenso , Eletrônica , Feminino , Humanos , Dosagem Radioterapêutica , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Brachytherapy ; 17(3): 621-627, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29496425

RESUMO

PURPOSE: Management of locally recurrent or persistent esophageal cancer (EC) after standard chemoradiation is challenging. This study updates our experience of treating medically inoperable EC patients with endoluminal high-dose-rate brachytherapy (EHDRBT) including the patients treated with a novel multiballoon channel centering esophageal applicator. METHODS AND MATERIALS: Thirty-three consecutive patients with early-stage primary (n = 7), posttreatment persistent (n = 7), and recurrent (n = 19) EC treated with EHDRBT at our institution were included. Median dose and treatment lengths were 14 Gy (range 10-17.5 Gy) and 6 cm (3.5-9.0 cm), respectively. Endoscopy and biopsy were performed 3 months after EHDRBT and then every 3-6 months thereafter. RESULTS: Median followup was 17.4 months (range 5.0-88.3). Grade 1 and 2 toxicities were observed in 13 (44.8%) and 11 (37.9%) patients, respectively. Grade 3 toxicity (tracheoesophageal fistula) was observed in 1 patient who had previously received two courses of external beam radiotherapy as well as a stent insertion. Median overall survival (OS) for entire cohort was 20.9 months, and 1-year OS was 78%. Complete response was achieved in 58.6% of patients with median time to failure and 1-year disease-free survival of 10.3 months (range 5.4-28.2) and 27%, respectively. CONCLUSIONS: For medically inoperable patients with early-stage primary or local posttreatment residual or recurrent EC, EHDRBT is a well-tolerated treatment option with minimal Grade ≥3 toxicity. Brachytherapy in our hands continues to be a safe treatment option. Although 58.6% of patients achieved a complete response and the OS of this cohort is relatively good, long-term local control and cure remains a challenge.


Assuntos
Braquiterapia/métodos , Neoplasias Esofágicas/radioterapia , Recidiva Local de Neoplasia/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Braquiterapia/efeitos adversos , Neoplasias Esofágicas/mortalidade , Esôfago/patologia , Esôfago/efeitos da radiação , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Lesões por Radiação/epidemiologia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Taxa de Sobrevida , Resultado do Tratamento
7.
Brachytherapy ; 17(2): 251-258, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29241706

RESUMO

PURPOSE: Rates of rectal toxicity after low-dose-rate (LDR) brachytherapy for prostate cancer are dependent on rectal dose, which is associated with rectal distance from prostate and implanted seeds. Placement of a hydrogel spacer between the prostate and rectum has proven to reduce the volume of the rectum exposed to higher radiation dose levels in the setting of external beam radiotherapy. We present our findings with placing a rectal hydrogel spacer in patients following LDR brachytherapy, and we further assess the impact of this placement on dosimetry and acute rectal toxicity. METHODS AND MATERIALS: Between January 2016 and April 2017, 74 patients had placement of a hydrogel spacer, immediately following a Pd-103 seed-implant procedure. Brachytherapy was delivered as follows: as a monotherapy to 26 (35%) patients; as part of planned combination therapy with external beam radiotherapy to 40 (54%) patients; or as a salvage monotherapy to eight (11%) patients. Postoperative MRI was used to assess separation achieved with rectal spacer. Acute toxicity was assessed retrospectively using Radiation Oncology Therapy Group radiation toxicity grading system. Rectal dosimetry was compared with a consecutive cohort of 136 patients treated with seed implantation at our institution without a spacer, using a 2-tailed paired Student's t test (p < 0.05 for statistical significance). RESULTS: On average, 11.2-mm (SD 3.3) separation was achieved between the prostate and the rectum. The resultant mean rectal volume receiving 100% of prescribed dose (V100%), dose to 1 cc of rectum (D1cc), and dose to 2 cc of rectum (D2cc) were 0 (SD 0.05 cc), 25.3% (SD 12.7), and 20.5% (SD 9.9), respectively. All rectal dosimetric parameters improved significantly for the cohort with spacer placement as compared with the nonspacer cohort. Mean prostate volume, prostate V100 and dose to 90% of gland (D90) were 29.3 cc (SD 12.4), 94.0% (SD 3.81), and 112.4% (SD 12.0), respectively. Urethral D20, D5cc, and D1cc were 122.0% (SD 17.27), 133.8% (SD 22.8), and 144.0% (SD 25.4), respectively. After completing all treatments, at the time of first the followup, 7 patients reported acute rectal toxicity-6 experiencing Grade 1 rectal discomfort and 1 (with preexisting hemorrhoids) experiencing Grade 1 bleeding. CONCLUSIONS: Injection of rectal spacer is feasible in the post-LDR brachytherapy setting and reduces dose to the rectum with minimal toxicity. Prostate and urethral dosimetries do not appear to be affected by the placement of a spacer. Further studies with long-term followup are warranted to assess the impact on reduction of late rectal toxicity.


Assuntos
Braquiterapia/métodos , Hidrogéis/administração & dosagem , Paládio/uso terapêutico , Próstata/patologia , Neoplasias da Próstata/radioterapia , Lesões por Radiação/prevenção & controle , Radioisótopos/uso terapêutico , Reto/efeitos da radiação , Idoso , Braquiterapia/efeitos adversos , Estudos de Coortes , Humanos , Imagem por Ressonância Magnética , Masculino , Tamanho do Órgão , Órgãos em Risco/efeitos da radiação , Paládio/efeitos adversos , Neoplasias da Próstata/diagnóstico por imagem , Doses de Radiação , Lesões por Radiação/etiologia , Radioisótopos/efeitos adversos , Dosagem Radioterapêutica , Doenças Retais , Estudos Retrospectivos , Terapia de Salvação , Uretra/efeitos da radiação
8.
Brachytherapy ; 16(6): 1257-1264, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28827006

RESUMO

PURPOSE: To present the clinical commissioning of a novel 103Pd directional brachytherapy device (CivaSheet) for intraoperative radiation therapy. METHODS AND MATERIALS: Clinical commissioning for the CivaSheet consisted of establishing: (1) source strength calibration capabilities, (2) experimental verification of TG-43 dosimetry parameters, (3) treatment planning system validation, and (4) departmental practice for dose specification and source ordering. Experimental verification was performed in water with radiochromic film calibrated with a 37 kVp X-ray beam. Percentage difference ([measurements - calculation]/calculation) and distance to agreement (difference between film-to-source distance and distance that minimized the percentage difference) were calculated. Nomogram values (in U/100 Gy) for all configurations (up to 20 × 20 sources) were calculated for source ordering. Clinical commissioning was used on patients enrolled in an ongoing Institutional Review Board-approved protocol. RESULTS: A source calibration procedure was established, and the treatment planning system was commissioned within standard clinical uncertainties. Percentage dose differences (distances to agreement) between measured and calculated doses were 8.6% (-0.12 mm), 0.6% (-0.01 mm), -6.4% (0.22 mm), and -10.0% (0.44 mm) at depths of 2.3, 5.1, 8.0, and 11.1 mm, respectively. All differences were within the experimental uncertainties. Nomogram values depended on sheet size and spatial extent. A value of 2.4U/100 Gy per CivaDot was found to satisfy most cases, ranging from 2.3 to 3.3U/100 Gy. Nomogram results depended on elongation of the treatment area with a higher variation observed for smaller treatment areas. Postimplantation dose evaluation was feasible. CONCLUSIONS: Commissioning and clinical deployment of CivaSheet was feasible using BrachyVision for postoperative dose evaluation. Experimental verification confirmed that the available TG-43 dosimetry parameters are accurate for clinical use.


Assuntos
Braquiterapia/instrumentação , Cuidados Intraoperatórios , Paládio , Próteses e Implantes , Braquiterapia/métodos , Calibragem , Dosimetria Fotográfica , Humanos , Radiometria/instrumentação , Dosagem Radioterapêutica
9.
Brachytherapy ; 16(4): 715-727, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28396178

RESUMO

Magnetic resonance imaging (MRI) is increasingly being used in radiation therapy, and integration of MRI into brachytherapy in particular is becoming more common. We present here a systematic review of the basic physics and technical aspects of incorporating MRI into prostate brachytherapy. Terminology and MRI system components are reviewed along with typical work flows in prostate high-dose-rate and low-dose-rate brachytherapy. In general, the brachytherapy workflow consists of five key components: diagnosis, implantation, treatment planning (scan + plan), implant verification, and delivery. MRI integration is discussed for diagnosis; treatment planning; and MRI-guided brachytherapy implants, in which MRI is used to guide the physical insertion of the brachytherapy applicator or needles. Considerations and challenges for establishing an MRI brachytherapy program are also discussed.

10.
Brachytherapy ; 16(1): 181-185, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27528589

RESUMO

PURPOSE: To report on the single-catheter high-dose-rate brachytherapy treatment of a 21-month-old girl child with an embryonal, botryoid-type, rhabdomyosarcoma limited to the external auditory canal (EAC). METHODS AND MATERIALS: A 2.4-mm diameter catheter was inserted into the right EAC and placed against the tympanic membrane. A computed tomography simulation scan was acquired. A brachytherapy treatment plan, in which 21 Gy in seven fractions was prescribed to a 1-mm depth along the distal 2 cm of the catheter, was generated. Treatments were delivered under anesthesia without complication. A dosimetric comparison between this plan and an intensity-modulated radiation therapy (IMRT) plan was then conducted. A clinical target volume (CTV), which encompassed a 1-mm margin along the distal 2 cm of the catheter, was delineated for both plans. Given positioning uncertainty under image guidance, a planning target volume (PTV = CTV + 3-mm margin) was defined for the IMRT plan. The IMRT plan was optimized for maximal CTV coverage but subsequently normalized to the same CTV volume receiving 100% of the prescription dose (V100) of the brachytherapy plan. RESULTS: The IMRT plan was normalized to the brachytherapy CTV V100 of 82.0%. The PTV V100 of this plan was 34.1%. The PTV exhibited dosimetric undercoverage within the middle ear and toward the external ear. Mean cochlea doses for the IMRT and brachytherapy plans were 26.7% and 10.5% of prescription, respectively. CONCLUSIONS: For rhabdomyosarcomas limited to the EAC, a standard brachytherapy catheter can deliver a highly conformal radiation plan that can spare the nearby cochlea from excess radiation.


Assuntos
Braquiterapia/métodos , Meato Acústico Externo , Neoplasias da Orelha/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Rabdomiossarcoma Embrionário/radioterapia , Cóclea/diagnóstico por imagem , Neoplasias da Orelha/diagnóstico por imagem , Feminino , Humanos , Lactente , Órgãos em Risco/diagnóstico por imagem , Radiometria , Dosagem Radioterapêutica , Radioterapia Conformacional/métodos , Rabdomiossarcoma Embrionário/diagnóstico por imagem , Tomografia Computadorizada por Raios X
11.
Radiother Oncol ; 121(1): 109-112, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27756494

RESUMO

BACKGROUND AND PURPOSE: To evaluate the incidence and predictors of hip toxicity postradiotherapy for localized prostate cancer. METHODS AND MATERIALS: 4067 prostate cancer patients were treated with external beam radiotherapy (EBRT; n=2569; 63%) or brachytherapy with or without supplemental EBRT (n=1508; 27%). 43% (n=1738) were treated with neo-adjuvant and concurrent ADT and 57% (n=2329) with radiotherapy alone. Hip toxicity was defined as moderate or severe pain upon ambulation with or without the need for hip-revision surgery. Median follow-up was 7years (range, 3-21years). RESULTS: One hundred twenty-one (2.7%) patients developed moderate-to-severe hip pain after radiotherapy affecting ambulation. Of these, 73 (60%) required hip replacement secondary to persistent hip pain. Among patients with baseline degenerative joint disease (DJD) changes on scans, 10-year incidence of hip-related toxicity was 11% versus 3% for those without such changes (P<.001). The only variables on multivariate analysis associated with hip-related toxicity post-radiotherapy were baseline DJD on imaging (P<.0001) and prolonged ADT for salvage therapy (P<.0001). CONCLUSIONS: Prostate EBRT or brachytherapy is associated with low incidence of long-term hip-related toxicity. The only variables identified associated with hip toxicity posttherapy was the presence of baseline DJD and prolonged salvage ADT posttreatment for patients developing recurrence.


Assuntos
Articulação do Quadril/efeitos da radiação , Artropatias/etiologia , Neoplasias da Próstata/radioterapia , Lesões por Radiação/etiologia , Idoso , Braquiterapia/efeitos adversos , Braquiterapia/métodos , Terapia Combinada , Humanos , Masculino , Pessoa de Meia-Idade , Terapia de Salvação
12.
Brachytherapy ; 15(5): 650-60, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27263059

RESUMO

PURPOSE: Skin surface dosimetric discrepancies between measured and treatment planning system predicted values were traced to source position sag inside the applicator and to source transit time. We quantified their dosimetric impact and propose corrections for clinical use. METHODS AND MATERIALS: We measured the dose profiles from the Varian Leipzig-style high-dose-rate (HDR) skin applicator, using EBT3 film, photon diode, and optically stimulated luminescence dosimeter for three different GammaMedplus HDR afterloaders. The measured dose profiles at several depths were compared with BrachyVision Acuros calculated profiles. To assess the impact of the source sag, two different applicator orientations were considered. The dose contribution during source transit was assessed by comparing diode measurements using an HDR timer and an electrometer timer. RESULTS: Depth doses measured using the three dosimeters were in good agreement, but were consistently higher than the Acuros dose calculations. Measurements with the applicator face up were significantly (exceeding 10%) lower than those in the face down position, due to source sag inside the applicator. Based on the inverse square law, the effective source sag was evaluated to be about 0.5 mm from the planned position. The additional dose during source transit was evaluated to be about 2.8% for 30 seconds of treatment with a 40700 U (10 Ci) source. CONCLUSION: With a very short source-to-surface distance, the small source sag inside the applicator has a significant dosimetric impact. This effect is unaccounted for in the vendor's treatment planning template and should be considered before the clinical use of the applicator. Further investigation of other applicators with large source lumen diameter may be warranted.


Assuntos
Braquiterapia/métodos , Planejamento da Radioterapia Assistida por Computador , Neoplasias Cutâneas/radioterapia , Braquiterapia/instrumentação , Humanos , Radiometria , Dosagem Radioterapêutica
13.
Brachytherapy ; 15(4): 420-425, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27180125

RESUMO

PURPOSE: Prostate low-dose-rate (LDR) brachytherapy involves implantation of radioactive seeds permanently into the prostate gland. During receptive anal intercourse, the penis of the partner may come in close proximity to the implanted prostate gland. We estimate the potential intrarectal dose rates and suggest guidance on radiation precautions. METHODS AND MATERIALS: One hundred two patients were included in the study. After implantation, with patients under anesthesia in the dorsal lithotomy position, a new set of ultrasound (US) images and a CT scan were obtained. The images were fused, radioactive seeds and US probe locations were determined on the CT, and prostate, bladder, and rectal contours were drawn on the US. Dose rates (cGy/h) were calculated for the portion of the US probe spanning the prostate for several dose-volume histogram parameters. RESULTS: Twenty patients were treated with (125)I and 82 patients with (103)Pd. Average dose rates at Day 0 to the portion of the US probe spanning the prostate were 2.1 ± 1.3 cGy/h and 2.5 ± 0.8 cGy/h for patients treated with (125)I and (103)Pd, respectively. After 60 days, average calculated probe dose drops to 1.0 ± 0.6 cGy/h and 0.2 ± 0.1 cGy/h for (125)I and (103)Pd, respectively. CONCLUSIONS: During the immediate weeks after prostate seed implant, the estimated intrarectal dose rates are higher in (103)Pd compared to (125)I. As (103)Pd decays faster than (125)I, 2 months after the implant, radiation exposure from (103)Pd becomes lower than (125)I. Receptive anal intercourse time should be kept as low as possible during 2 and 6 months after low-dose-rate brachytherapy of the prostate with (103)Pd and (125)I, respectively.


Assuntos
Braquiterapia , Homossexualidade Masculina , Radioisótopos do Iodo/uso terapêutico , Paládio/uso terapêutico , Neoplasias da Próstata/radioterapia , Doses de Radiação , Segurança , Comportamento Sexual , Humanos , Masculino , Órgãos em Risco/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Radioisótopos/uso terapêutico , Radiometria , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Estudos Retrospectivos , Fatores de Tempo , Tomografia Computadorizada por Raios X , Ultrassonografia , Bexiga Urinária/diagnóstico por imagem
14.
Brachytherapy ; 15(3): 266-273, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27009848

RESUMO

PURPOSE: To report the long-term control and toxicity outcomes of patients with clinically localized prostate cancer, who underwent low-dose-rate prostate brachytherapy with magnetic resonance spectroscopic image (MRSI)-directed dose escalation to intraprostatic regions. METHODS AND MATERIALS: Forty-seven consecutive patients between May 2000 and December 2003 were analyzed retrospectively. Each patient underwent a preprocedural MRSI, and MRS-positive voxels suspicious for malignancy were identified. Intraoperative planning was used to determine the optimal seed distribution to deliver a standard prescription dose to the entire prostate, while escalating the dose to MRS-positive voxels to 150% of prescription. Each patient underwent transperineal implantation of radioactive seeds followed by same-day CT for postimplant dosimetry. RESULTS: The median prostate D90 (minimum dose received by 90% of the prostate) was 125.7% (interquartile range [IQR], 110.3-136.5%) of prescription. The median value for the MRS-positive mean dose was 229.9% (IQR, 200.0-251.9%). Median urethra D30 and rectal D30 values were 142.2% (137.5-168.2%) and 56.1% (40.1-63.4%), respectively. Median followup was 86.4 months (IQR, 49.8-117.6). The 10-year actuarial prostate-specific antigen relapse-free survival was 98% (95% confidence interval, 93-100%). Five patients (11%) experienced late Grade 3 urinary toxicity (e.g., urethral stricture), which improved after operative intervention. Four of these patients had dose-escalated voxels less than 1.0 cm from the urethra. CONCLUSIONS: Low-dose-rate brachytherapy with MRSI-directed dose escalation to suspicious intraprostatic regions exhibits excellent long-term biochemical control. Patients with dose-escalated voxels close to the urethra were at higher risk of late urinary stricture.


Assuntos
Braquiterapia/métodos , Espectroscopia de Ressonância Magnética , Neoplasias da Próstata/radioterapia , Idoso , Braquiterapia/efeitos adversos , Intervalo Livre de Doença , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Lesões por Radiação/etiologia , Dosagem Radioterapêutica , Reto/efeitos da radiação , Estudos Retrospectivos , Fatores de Tempo , Uretra/efeitos da radiação , Estreitamento Uretral/etiologia
15.
Brachytherapy ; 15(2): 208-15, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26825857

RESUMO

PURPOSE: Local recurrence is a significant problem after surgical resection of thoracic tumors. As intraoperative radiotherapy (IORT) can deliver radiation directly to the threatened margin, we have used this therapy in an attempt to reduce local recurrence, using high-dose-rate (HDR) as well as low-dose-rate (LDR) techniques. METHODS AND MATERIALS: We performed a retrospective review of patients undergoing LDR ((125)I) mesh placement or HDR ((192)Ir) afterloading therapy during lung tumor resection between 2001 and 2013 at our institution. Competing risks methods were used to estimate the cumulative incidence of local failure. We also assessed possible predictive factors of local failure. RESULTS: Fifty-nine procedures (41 LDR and 18 HDR) were performed on 58 patients. Median follow-up was 55.1 months. Cumulative incidence of local failure at 1, 2, and 3 years was 28.5%, 34.2%, and 34.2%, respectively. Median overall survival was 39.9 months. There was no significant difference in local failure according to margin status, HDR vs. LDR, use of adjuvant external beam radiotherapy, or metastatic vs. primary tumor. Two patients (3.4%) experienced Grade 3+ toxicities likely related to brachytherapy. Additionally, 7 patients experienced Grade 3+ postsurgical complications unlikely related to brachytherapy. CONCLUSIONS: IORT is associated with good local control after resection of thoracic tumors otherwise at very high risk for local recurrence. There is a low incidence of severe toxicity attributable to brachytherapy. HDR-IORT appears to have equivalent outcomes to LDR-IORT. HDR or LDR-IORT can, therefore, be considered in situations where the oncologic completeness of thoracic tumor resection is in doubt.


Assuntos
Braquiterapia , Neoplasias Pulmonares/radioterapia , Recidiva Local de Neoplasia/prevenção & controle , Adulto , Idoso , Braquiterapia/efeitos adversos , Humanos , Cuidados Intraoperatórios , Neoplasias Pulmonares/cirurgia , Pessoa de Meia-Idade , Neoplasia Residual , Dosagem Radioterapêutica , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
16.
Technol Cancer Res Treat ; 14(3): 298-304, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25230715

RESUMO

PURPOSE: To evaluate visibility, artifacts, and distortions of various commercial markers in magnetic resonance imaging (MRI), computer tomography (CT), and ultrasound imaging used for radiotherapy planning and treatment guidance. METHODS: We compare 2 solid gold markers, 4 gold coils, and 1 polymer marker from 3 vendors. Imaging modalities used were 3-T and 1.5-T GE MRIs, Siemens Sequoia 512 Ultrasound, Phillips Big Bore CT, Varian Trilogy linear accelerator (cone-beam CT [CBCT], on-board imager kilovoltage [OBI-kV], electronic portal imaging device megavoltage [EPID-MV]), and Medtronic O-ARM CBCT. Markers were imaged in a 30 × 30 × 10 cm(3) custom bolus phantom. In one experiment, Surgilube was used around the markers to reduce air gaps. Images were saved in Digital Imaging and Communications in Medicine (DICOM) format and analyzed using an in-house software. Profiles across the markers were used for objective comparison of the markers' signals. The visibility and artifacts/distortions produced by each marker were assessed qualitatively and quantitatively. RESULTS: All markers are visible in CT, CBCT, OBI-kV, and ultrasound. Gold markers below 0.75 mm in diameter are not visible in EPID-MV images. The larger the markers, the more CT and CBCT image artifacts there are, yet the degree of the artifact depends on scan parameters and the scanner itself. Visibility of gold coils of 0.75 mm diameter or larger is comparable across all imaging modalities studied. The polymer marker causes minimal artifacts in CT and CBCT but has poor visibility in EPID-MV. Gold coils of 0.5 mm exhibit poor visibility in MRI and EPID-MV due to their small size. Gold markers are more visible in 3-T T1 gradient-recalled echo than in 1.5-T T1 fast spin-echo, depending on the scan sequence. In this study, all markers are clearly visible on ultrasound. CONCLUSION: All gold markers are visible in CT, CBCT, kV, and ultrasound; however, only the large diameter markers are visible in MV. When MR and EPID-MV imagers are used, the selection of fiducial markers is not straightforward. For hybrid kV/MV image-guided radiotherapy imaging, larger diameter markers are suggested. If using kV imaging alone, smaller sized markers may be used in smaller sized patients in order to reduce artifacts. Only larger diameter gold markers are visible across all imaging modalities.


Assuntos
Ouro/química , Polímeros/química , Algoritmos , Artefatos , Tomografia Computadorizada de Feixe Cônico/métodos , Marcadores Fiduciais , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imagem por Ressonância Magnética/métodos , Aceleradores de Partículas , Imagens de Fantasmas , Radioterapia Guiada por Imagem/métodos , Software , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos
17.
Brachytherapy ; 14(2): 202-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25483021

RESUMO

PURPOSE: Sterilization of surgical margins for lesions involving the dura is complicated by the tolerance of the spinal cord and/or cauda equina, especially in the setting of prior radiation therapy (RT); use of intraoperative brachytherapy may allow local delivery of therapeutic dose without damaging sensitive structures. METHODS AND MATERIALS: Patients with malignant lesions involving the dura received intraoperative brachytherapy with a (32)P plaque after maximal resection of the tumor. Local recurrence (LR) was analyzed using competing risks analysis; overall survival was analyzed using Kaplan-Meier statistics. RESULTS: Between September 2009 and April 2013, 68 patients with 69 lesions in the spine were treated with the (32)P plaque. Median followup was 10 months. Most patients (n=59, 85.5%) had previously been treated with at least one course of prior RT to the treated site. About 38 (55%) lesions received postoperative RT (median dose, 30 Gy; range, 18-30 Gy). The LR and overall survival at 12 months were 25.5% (95% confidence interval [CI]=15.5-37%) and 59.5% (95% CI=46-73%), respectively. For patients who received postoperative RT, LR at 12 months was 18.5% (95% CI=7.5-33%) compared with 34% (95% CI=18-51%) for those who were treated with the plaque alone (p=0.08 and 0.04 on univariate and multivariable analysis, respectively). There were no acute or long-term complications from treatment observed in this cohort. CONCLUSIONS: The (32)P intraoperative brachytherapy plaque is a useful adjunct to surgical intervention for primary recurrent and metastatic lesions of the spine involving the dura, and is not associated with additional toxicity.


Assuntos
Braquiterapia/métodos , Dura-Máter , Vértebras Lombares , Recidiva Local de Neoplasia/epidemiologia , Radioisótopos de Fósforo/uso terapêutico , Neoplasias da Medula Espinal/radioterapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Incidência , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , New York , Estudos Retrospectivos , Neoplasias da Medula Espinal/diagnóstico , Neoplasias da Medula Espinal/cirurgia , Taxa de Sobrevida/tendências , Adulto Jovem
18.
Brachytherapy ; 14(2): 179-84, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25500364

RESUMO

PURPOSE: To investigate the association between statin use and prostate cancer outcomes in intermediate- and high-risk patients treated with brachytherapy for prostate cancer. METHODS AND MATERIALS: Between 1998 and 2010, 754 men with National Comprehensive Cancer Network intermediate- (n = 627) and high-risk (n = 127) prostate cancer were treated with prostate brachytherapy at our institution. Patients received either low-dose-rate or high-dose-rate brachytherapy as monotherapy or in combination with supplemental external beam radiotherapy. Two hundred eighty-five patients (37.8%) also received androgen-deprivation therapy. Two hundred seventy-three men (36.2%) were identified as taking statin medication before initiating radiation therapy. Prostate-specific antigen relapse-free survival (PSA-RFS), distant metastasis-free survival (DMFS), and overall survival were compared using log-rank tests. Associations of patient and treatment characteristics with outcomes were analyzed with univariate and multivariate regression. The median followup was 48 months. RESULTS: The 8-year PSA-RFS for intermediate-risk, high-risk, and all patients was 92.2%, 64.1%, and 87.7%, respectively. The 8-year DMFS was 97.1%, 82.9%, and 94.9%, respectively. The 8-year overall survival for the entire cohort was 86.6%. There were no significant differences between statin users and nonusers when stratified by risk group, nor when analyzed as a full cohort. On multivariate analysis, Gleason score 4 + 3 = 7 and >7 were significantly associated with worse PSA-RFS (p ≤ 0.003 and <0.001, respectively). Gleason score > 7 (p = 0.008) and the use of neoadjuvant androgen-deprivation therapy (p = 0.03) was associated with worse DMFS. Statin use did not significantly impact PSA-RFS or DMFS. CONCLUSIONS: Pretreatment statin use is not associated with improved outcomes in intermediate- and high-risk patients undergoing prostate brachytherapy-based regimens for prostate cancer.


Assuntos
Braquiterapia/métodos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Neoplasias da Próstata/radioterapia , Idoso , Seguimentos , Humanos , Masculino , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/tratamento farmacológico , Estudos Retrospectivos , Resultado do Tratamento
19.
JAMA Ophthalmol ; 133(3): 283-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25502420

RESUMO

IMPORTANCE: Adjunct treatments for conjunctival malignancies are needed when standard therapy provides limited benefits or fails. OBJECTIVE: To describe the results of patients with diffuse conjunctival neoplasms treated with radioactive phosphorus 32 (32P)-impregnated flexible film. DESIGN, SETTING, AND PARTICIPANTS: This retrospective case series between January 1, 2010, and January 1, 2013, was conducted at Memorial Sloan-Kettering Cancer Center, a tertiary referral center. The study was conducted on 7 eyes of 6 patients treated for diffuse conjunctival squamous cell carcinoma, sebaceous carcinoma, or lymphoma that had recurrent or residual disease after primary treatment. INTERVENTIONS: Patients underwent mapping biopsies and detailed conjunctival drawings to delineate the pathologic extent of the disease. The brachytherapy film used for treatment was the RIC Conformal Source Model 100 (RIC-100, RI Consultants). The RIC-100 is a flexible, thin (approximately 0.5-mm) film made of a polymer chemically bound to 32P. The radioactive 32P film was placed intraoperatively, allowed to stay in place until the prescription dose was reached, and then removed. The median dose at the prescription point (1 mm from the surface of the film) was 15 Gy (range, 5-17 Gy). MAIN OUTCOMES AND MEASURES: Patients were tested for best-corrected visual acuity, recurrence-free survival, and adverse events scored by using the Adult Comorbidity Evaluation-27 scale. RESULTS: Between 2010 and 2013, 7 eyes of 6 patients were treated. The median age of patients was 70 years. All patients had a recurrent or persistent neoplasm. Four patients with squamous cell carcinoma, 1 with sebaceous carcinoma, and 1 with metachronous bilateral lymphomas were treated. The median treatment time was 19 minutes (range, 10-52 minutes). The median follow-up was 24.9 months (range, 3.1-38.2 months). Recurrence-free survival 24 months after brachytherapy was 75% (95% CI, 19-89.1). Two moderate adverse events and 1 severe adverse event occurred. Visual acuity was stable or improved in 5 of the 7 eyes (ie, better than 20/70 in the 5 patients who retained their treated eye). CONCLUSIONS AND RELEVANCE: Our results show the use of an intraoperative high-dose rate of 32P brachytherapy in selected cases of recalcitrant diffuse conjunctival neoplasms. This technique offers a novel adjunct in the treatment of these cancers. Further follow-up and study are warranted.


Assuntos
Adenocarcinoma Sebáceo/radioterapia , Braquiterapia/métodos , Carcinoma de Células Escamosas/radioterapia , Neoplasias da Túnica Conjuntiva/radioterapia , Linfoma de Células T/radioterapia , Radioisótopos de Fósforo/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Humanos , Cuidados Intraoperatórios , Masculino , Pessoa de Meia-Idade , Radioisótopos de Fósforo/efeitos adversos , Dosagem Radioterapêutica , Radioterapia Adjuvante , Estudos Retrospectivos , Acuidade Visual/fisiologia
20.
Int J Radiat Oncol Biol Phys ; 90(2): 312-9, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25304791

RESUMO

PURPOSE: To identify an anatomic structure predictive for acute (AUT) and late (LUT) urinary toxicity in patients with prostate cancer treated with low-dose-rate brachytherapy (LDR) with or without external beam radiation therapy (EBRT). METHODS AND MATERIALS: From July 2002 to January 2013, 927 patients with prostate cancer (median age, 66 years) underwent LDR brachytherapy with Iodine 125 (n=753) or Palladium 103 (n=174) as definitive treatment (n=478) and as a boost (n=449) followed by supplemental EBRT (median dose, 50.4 Gy). Structures contoured on the computed tomographic (CT) scan on day 0 after implantation included prostate, urethra, bladder, and the bladder neck, defined as 5 mm around the urethra between the catheter balloon and the prostatic urethra. AUT and LUT were assessed with the Common Terminology Criteria for Adverse Events, version4. Clinical and dosimetric factors associated with AUT and LUT were analyzed with Cox regression and receiver operating characteristic analysis to calculate area under the receiver operator curve (ROC) (AUC). RESULTS: Grade ≥2 AUT and grade ≥2 LUT occurred in 520 patients (56%) and 154 patients (20%), respectively. No grade 4 toxicities were observed. Bladder neck D2cc retained a significant association with AUT (hazard ratio [HR], 1.03; 95% confidence interval [CI], 1.03-1.04; P<.0001) and LUT (HR, 1.01; 95% CI, 1.00-1.03; P=.014) on multivariable analysis. In a comparison of bladder neck with the standard dosimetric variables by use of ROC analysis (prostate V100 >90%, D90 >100%, V150 >60%, urethra D20 >130%), bladder neck D2cc >50% was shown to have the strongest prognostic power for AUT (AUC, 0.697; P<.0001) and LUT (AUC, 0.620; P<.001). CONCLUSIONS: Bladder neck D2cc >50% was the strongest predictor for grade ≥2 AUT and LUT in patients treated with LDR brachytherapy. These data support inclusion of bladder neck constraints into brachytherapy planning to decrease urinary toxicity.


Assuntos
Braquiterapia/efeitos adversos , Neoplasias da Próstata/radioterapia , Bexiga Urinária/efeitos da radiação , Idoso , Análise de Variância , Área Sob a Curva , Braquiterapia/métodos , Humanos , Radioisótopos do Iodo/uso terapêutico , Masculino , Pessoa de Meia-Idade , Paládio/uso terapêutico , Curva ROC , Dosagem Radioterapêutica , Estudos Retrospectivos , Transtornos Urinários/etiologia
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