RESUMO
PURPOSE: A phase II trial of accelerated fractionation radiation with concurrent cisplatin and paclitaxel chemotherapy was performed to investigate the role of the paclitaxel, when substituted for fluorouracil (5-FU), in the chemoradiotherapy of esophageal cancer. PATIENTS AND METHODS: Patients with an esophageal ultrasound stage of T(3) or N(1) or M(1) (nodal) esophageal cancer were treated with two courses of a cisplatin infusion (20 mg/m(2)/d for 4 days) and paclitaxel (175 mg/m(2) over 24 hours) concurrent with a split course of accelerated fractionation radiation (1.5 Gy bid to a total dose of 45 Gy). Surgical resection was performed 4 to 6 weeks later followed by a single identical postoperative course of chemoradiotherapy (24 Gy) in patients with significant residual tumor at surgery. Toxicity and results of this treatment were retrospectively compared with our previous 5-FU and cisplatin chemoradiotherapy experience. RESULTS: Between September 1995 and July 1997, 40 patients were entered onto this study. Although dysphagia proved worse in our 5-FU-treated patients, profound leukopenia and a need for unplanned hospitalization were significantly more common in the paclitaxel group. Thirty-seven patients (93%) proved resectable for cure. The 3-year projected overall survival is 30%, locoregional control is 81%, and distant metastatic disease control is 44%. When compared with a similarly staged cohort of 5-FU-treated patients, there was no advantage for any survival function studied. CONCLUSION: This paclitaxel-based treatment regimen for locoregionally advanced esophageal cancer produced increased toxicity with no improvement in results when compared with our previous 5-FU experience. Paclitaxel-based treatments must be carefully and prospectively studied before their incorporation into the standard management of esophageal cancer.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/uso terapêutico , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/radioterapia , Fluoruracila/uso terapêutico , Paclitaxel/uso terapêutico , Radiossensibilizantes/uso terapêutico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Distribuição de Qui-Quadrado , Cisplatino/efeitos adversos , Terapia Combinada , Progressão da Doença , Fracionamento da Dose de Radiação , Neoplasias Esofágicas/mortalidade , Feminino , Fluoruracila/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Paclitaxel/efeitos adversos , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida , Resultado do TratamentoRESUMO
Radiotherapy (RT) plays a major role in the palliation of cancer symptoms. Cancer-related bone pain, bronchial obstruction, superior vena cava syndrome, spinal cord compression, and central neurologic dysfunction due to brain metastases are all treated effectively and safely by RT. Although numerous techniques and radiation dose fractionation schemes are used in practice, substantial palliation often may be accomplished by just two to 10 appropriately targeted treatments. Thus, palliative RT regimens need not be highly protracted to be effective. Several new techniques, including strontium 89 radiopharmaceutical therapy, high-dose-rate endobronchial brachytherapy, and stereotactic radiosurgery, are now being evaluated in clinical trials to determine their efficacy in the relief of various oncologic symptoms. Palliative RT continues to be a mainstay of treatment in the management of cancer patients with advanced disease.
Assuntos
Neoplasias Ósseas/secundário , Neoplasias Encefálicas/secundário , Neoplasias Hepáticas/secundário , Neoplasias/radioterapia , Cuidados Paliativos , Neoplasias Torácicas/secundário , Neoplasias Ósseas/radioterapia , Neoplasias Encefálicas/radioterapia , Humanos , Neoplasias Hepáticas/radioterapia , Compressão da Medula Espinal/radioterapia , Neoplasias Torácicas/radioterapiaRESUMO
Radiotherapy is often used for the palliative treatment of advanced cancer. Although each cancer is unique in its histology and natural history, there are several scenarios that repeatedly challenge physicians. Specifically, skeletal metastases, spinal cord compression, brain metastasis, bronchial obstruction, and vena cava obstruction are regularly encountered. This review will discuss the diagnosis and treatment of these common important situations.
Assuntos
Neoplasias/radioterapia , Cuidados Paliativos , Neoplasias Ósseas/radioterapia , Neoplasias Ósseas/secundário , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Humanos , Pneumopatias Obstrutivas/etiologia , Pneumopatias Obstrutivas/radioterapia , Neoplasias/complicações , Compressão da Medula Espinal/etiologia , Compressão da Medula Espinal/radioterapia , Síndrome da Veia Cava Superior/etiologia , Síndrome da Veia Cava Superior/radioterapiaRESUMO
PURPOSE: To compare the dosimetry of the traditional two step procedure (volume study + treatment planning several weeks later) with that of an OR-based single procedure in which these two steps follow one another immediately. Computer generated treatment plans were used in both procedures. METHODS AND MATERIALS: Several dosimetric parameters relating to target coverage were obtained from dose volume histograms of CT-based evaluation plans developed either 1 or 3 days following seed implantation. A total of 113 patients with early stage (T1C, T2A) prostate cancer were used for this retrospective study. RESULTS: The fraction of target (prostate) covered by the prescription dose (144 Gy), 90% of the prescription dose (115 Gy), and the dose encompassing 90% of the target in the evaluation plan were all statistically significantly improved for OR-based plans compared to pre-planned cases. CONCLUSION: In our hands, there is a small but significant improvement in dose coverage of the prostate when the ultrasound volume study and treatment planning are combined into a single procedure.
Assuntos
Braquiterapia/métodos , Neoplasias da Próstata/radioterapia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Humanos , Radioisótopos do Iodo/uso terapêutico , Masculino , Seleção de Pacientes , Neoplasias da Próstata/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , UltrassonografiaRESUMO
PURPOSE: The preplanned technique used for permanent prostate brachytherapy has limitations that may be overcome by intraoperative planning. The goal of the American Brachytherapy Society (ABS) project was to assess the current intraoperative planning process and explore the potential for improvement in intraoperative treatment planning (ITP). METHODS AND MATERIALS: Members of the ABS with expertise in ITP performed a literature review, reviewed their clinical experience with ITP, and explored the potential for improving the technique. RESULTS: The ABS proposes the following terminology in regard to prostate planning process: *Preplanning--Creation of a plan a few days or weeks before the implant procedure. *Intraoperative planning--Treatment planning in the operating room (OR): the patient and transrectal ultrasound probe are not moved between the volume study and the seed insertion procedure. * Intraoperative preplanning--Creation of a plan in the OR just before the implant procedure, with immediate execution of the plan. *Interactive planning--Stepwise refinement of the treatment plan using computerized dose calculations derived from image-based needle position feedback. *Dynamic dose calculation--Constant updating of dose distribution calculations using continuous deposited seed position feedback. Both intraoperative preplanning and interactive planning are currently feasible and commercially available and may help to overcome many of the limitations of the preplanning technique. Dosimetric feedback based on imaged needle positions can be used to modify the ITP. However, the dynamic changes in prostate size and shape and in seed position that occur during the implant are not yet quantifiable with current technology, and ITP does not obviate the need for postimplant dosimetric analysis. The major current limitation of ITP is the inability to localize the seeds in relation to the prostate. Dynamic dose calculation can become a reality once these issues are solved. Future advances can be expected in methods of enhancing seed identification, in imaging techniques, and in the development of better source delivery systems. Additionally, ITP should be correlated with outcome studies, using dosimetric, toxicity, and efficacy endpoints. CONCLUSION: ITP addresses many of the limitations of current permanent prostate brachytherapy and has some advantages over the preplanned technique. Further technologic advancement will be needed to achieve dynamic real-time calculation of dose distribution from implanted sources, with constant updating to allow modification of subsequent seed placement and consistent, ideal dose distribution within the target volume.
Assuntos
Braquiterapia , Neoplasias da Próstata/radioterapia , Planejamento da Radioterapia Assistida por Computador , Humanos , Imageamento por Ressonância Magnética , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Dosagem Radioterapêutica , Tomografia Computadorizada por Raios X , UltrassonografiaRESUMO
PURPOSE: Restenosis after percutaneous transluminal coronary angioplasty (PTCA) remains a limitation of this technique. Arterial wall cell proliferation is a component of restenosis preventable with intravascular brachytherapy. This study attempts to locate the sites of cellular proliferation after PTCA so as to aid the optimization of this therapy. METHODS AND MATERIALS: Autopsy records from January 1, 1985 through December 31, 1995 were reviewed, and 27 patients who received PTCA prior to death were identified who also had evidence of PTCA on histologic examination of the arterial sections. The sections were subjected to immunohistochemical staining for proliferating cell nuclear antigen (PCNA) to detect the proliferating cells in the arterial sections, followed by image analysis to determine the proliferative index (PI) of all regions and layers of the section. RESULTS: The PI did not differ significantly according to vessel region (plaque, plaque shoulder, or portion of vessel wall with lowest plaque burden), vessel layer (intima, media, adventitia), or evidence of prior PTCA. There was a trend toward a higher PI in young lesions. CONCLUSION: Cell proliferation in the vascular wall after PTCA was found throughout the treated arterial section's axial plane, not only in the periluminal region.
Assuntos
Angioplastia Coronária com Balão , Doença das Coronárias/patologia , Antígeno Nuclear de Célula em Proliferação/análise , Biomarcadores/análise , Braquiterapia , Divisão Celular , Núcleo Celular/química , Doença das Coronárias/etiologia , Doença das Coronárias/radioterapia , Humanos , Recidiva , Grau de Desobstrução VascularRESUMO
BACKGROUND: This study assessed toxicity, tumor response, disease control, and survival after short-course induction chemoradiotherapy and surgical resection in patients with stage III non-small-cell lung carcinoma. METHODS: Forty-five patients with stage III non-small-cell lung carcinoma received 12-day induction therapy of a 96-hour continuous infusion of cisplatin (20 mg/m2 per day), 24-hour infusion of paclitaxel (175 mg/m2), and concurrent accelerated fractionation radiation therapy (1.5 Gy twice daily) to a dose of 30 Gy. Surgical resection was scheduled for 4 weeks later. Postoperatively, a second identical course of chemotherapy and concurrent radiation therapy (30 to 33 Gy) was given. RESULTS: Induction toxicity resulted in hospitalization of 18 (40%) patients for neutropenic fever. No induction deaths occurred. Of 40 (89%) patients who underwent thoracotomy, resection for cure was possible in 32 (71%) patients. Pathologic response was noted in 21 (47%) patients, and 14 (31%) were downstaged to mediastinal node negative (stage 0, I, or II). At a median follow-up of 19 months, 24 patients were alive, 10 with recurrent disease. Of 21 deaths, 16 were from recurrent disease, three were from treatment, and two were unrelated. Recurrent disease was distant in 21 patients, distant and locoregional in 2, and locoregional in 3. The Kaplan-Meier projected 24-month survival is 49%. Projected 24-month survival is 61% for stage IIIA, 17% for stage IIIB (p = 0.035); 84% for pathologic responders, 22% for nonresponders (p<0.001); 83% for downstaged patients (stage 0, I, or II), 33% for those not downstaged (p = 0.005); and 63% for resectable patients, 14% for unresectable patients (p = 0.007). CONCLUSIONS: We conclude that short-course neoadjuvant therapy with paclitaxel (1) has manageable toxicity and a low treatment mortality, (2) results in good tumor response and downstaging, (3) provides excellent locoregional control with most recurrences being distant, and (4) has improved the median survival compared with historical controls. Survival was better in stage IIIA patients, resectable patients, pathologic responders, and patients downstaged to mediastinal node negative disease (stage 0, I, or II).
Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/terapia , Terapia Neoadjuvante/métodos , Paclitaxel/administração & dosagem , Antineoplásicos Fitogênicos/efeitos adversos , Antineoplásicos Fitogênicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Cisplatino/uso terapêutico , Fracionamento da Dose de Radiação , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Paclitaxel/efeitos adversos , Paclitaxel/uso terapêutico , Cuidados Pré-Operatórios , Análise de Sobrevida , Fatores de TempoRESUMO
Target motion due to breathing is one of the major obstacles in dose escalation of radiation therapy to some tumors in the thoracoabdominal region. The development of beam gating or target motion tracking techniques provides a possibility to reduce normal tissue volume in a treatment field. Tumor motion monitoring in those techniques plays a crucial role, but has not yet been adequately explored. This paper reports our preliminary investigation on breath introduced tumor motion. Tumor locations and motion properties were determined from digitized fluoroscopic videos acquired during patient simulation. Image distortion due to irregularities in the imaging chain, such as the pincushion distortion, was corrected with a polynomial unwarping method. Temporal Fourier transformation of the fluoroscopic video was introduced to convert the motion information over time to a static view of a motion field, in which regions with different motion ranges can be directly measured. Patient breathing patterns vary from patient to patient and so does the kinematic behavior of individual tumors. In order to evaluate the feasibility for tracking internal target motion with nonionizing-radiation techniques, motion patterns between internal targets and external radio opaque markers placed on patient's chest during fluoroscopic video acquisition were compared. For some patients, significant motion phase discrepancies between an internal target and an external marker have been observed. Quantitative measurements are reported. These results will be useful in the design of a motion tracking or gated radiotherapy system.
Assuntos
Fluoroscopia , Neoplasias Pulmonares/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Análise de Fourier , Humanos , Movimento , Imagens de Fantasmas , Respiração , Gravação de VideoteipeRESUMO
PURPOSE: The objective was to determine the dosimetry of a potential endovascular brachytherapy source consisting of a coiled tungsten wire mounted on the distal end of a drive wire and neutron-activated to contain the parent-daughter nuclides tungsten-188 (188W) and rhenium-188 (188Re). METHODS: A coiled tungsten wire 40 mm in length was neutron-activated by double-neutron capture for 78 hours at 1.9 x 10(15) h/cm2/s to contain 925 MBq (25 mCi) of 188W/188Re in equilibrium. The dose-fall off from this source was determined using three independent methods: (a) Thermoluminescence dosimetry with small LiF-100 rods, (b) Gafchromic film dosimetry, and (c) Bang gel dosimetry. In addition, a Monte Carlo simulation was performed to compute the beta-dose. RESULTS: Each of the three measurement methods recorded similar values for the dose fall-off within the distances useful for endovascular brachytherapy. The Monte Carlo calculations closely approximated the measured results in the treatment range between 1 and 3 mm and may thus be useful for evaluating changing geometries in the development of catheters and source setups. A 2 min restenosis treatment delivering 20 Gy at a radius of 2 mm would require a source of 1384.8 MBq/cm (37.4 mCi/cm). CONCLUSIONS: The dose distribution from a 188W/188Re source is similar to that of a 90Y-source. An added advantage of the 188W/188Re source is that it can be used for at least two months and still provides fast treatment times because of the parent isotope's half-life of 69 days. The additional gamma emission from the source is too small to impose a serious radiological hazard. The high atomic number and density of the source material allows direct fluoroscopic imaging without additional markers.
Assuntos
Braquiterapia/métodos , Endotélio Vascular/efeitos da radiação , Radioisótopos/uso terapêutico , Radiometria/métodos , Rênio/uso terapêutico , Dosimetria Termoluminescente/métodos , Tungstênio/uso terapêutico , Partículas beta , Braquiterapia/instrumentação , Elétrons , Dosimetria Fotográfica/instrumentação , Dosimetria Fotográfica/métodos , Fluoretos/química , Géis , Compostos de Lítio/química , Método de Monte Carlo , Polímeros , Dosimetria Termoluminescente/instrumentaçãoRESUMO
The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment. This review focuses on locally advanced prostate cancer and the evidence for treatment outcomes, both toxicity and efficacy, across the three major treatment modalities of external beam radiotherapy, brachytherapy and surgery. Only data that could pass contemporary quality metrics were used to form this report. This body of literature suffers from an absence of trials prospectively comparing therapies for efficacy and a lack of long-term prospective comparisons of toxicity. Upon review of these data, the authors concluded that there are several acceptable methods for the treatment of locally advanced prostate cancer that is highly dependent of the patient's clinical (both prostate cancer-specific and comorbidity-specific) parameters at diagnosis.
Assuntos
Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia , Antineoplásicos/uso terapêutico , Humanos , Masculino , Prostatectomia , Neoplasias da Próstata/tratamento farmacológico , Radioterapia/métodosRESUMO
OBJECTIVES: To compare perioperative costs associated with radical retropubic prostatectomy (RRP) to transperineal brachytherapy (BXRT) with iodine-125 (125I) seeds in the treatment of localized prostate cancer. METHODS: Actual costs per case for the perioperative period were compiled prospectively for 583 consecutive patients undergoing RRP or BXRT between January 1, 1997 and October 30, 1998 using a hospital-wide cost accounting system. The total cost per case included both technical and professional components. The technical costs included those incurred for anesthesiology, laboratory medicine, medicine, pharmacy, nursing, radiology, 125I seeds, and BXRT technicians. Professional costs included fees from anesthesiology, laboratory, medicine, urology, radiation oncology, and physics. Cases were divided into three groups for analysis: group 1, RRP (n = 404); group 2, BXRT with planning ultrasound performed in the office setting before implantation (n = 107); and group 3, BXRT with planning ultrasound performed in the operating room at the time of implantation (n = 72). Results are reported as relative cost ratios, with RRP assigned a relative cost of 1.0. RESULTS: The total relative perioperative cost for BXRT exceeded that for RRP by 85% to 105%. Technical cost, exclusive of 125I seeds, was substantially lower for BXRT (relative cost 0.36 to 0.42) but was more than offset by the cost of the seeds when comparing total cost with RRP. Performance of the planning ultrasound in the operating room (group 3) increased the total cost by 20%. The categorical technical costs for both BXRT groups were significantly lower for anesthesiology, laboratory medicine, medicine, pharmacy, and nursing but were significantly higher for radiology. The total professional costs were similar for all groups. CONCLUSIONS: Perioperative costs of BXRT with 125I seeds are substantially higher than RRP in the treatment of localized prostate cancer, primarily because of the cost of the seeds.