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1.
Med Dosim ; 26(2): 205-13, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11444523

RESUMO

At Emory Clinic intensity-modulated radiation therapy (IMRT) was started by using dynamic multileaf collimators (dMLC) as electronic tissue compensators in August 1998. Our IMRT program evolved with the inclusion of a commercially available inverse treatment planning system in September 1999. While the introduction of electronic tissue compensators into clinical use did not affect the customary radiation oncology practice, inverse treatment planning does alter our basic routines. Basic concepts of radiation therapy port designs for inverse treatment planning are different from conventional or 3D conformal treatments. With inverse treatment planning, clinicians are required to outline a gross tumor volume (GTV), a clinical target volume (CTV), critical normal structures, and to design a planning target volume (PTV). Clinicians do not designate the volume to be shielded. Because each IMRT radiation portal is composed of many beamlets with varying intensities, methods and practice used to verify delivered dose from IMRT portals are also different from conventional treatment portals. Often, the validity of measured data is in doubt. Therefore, checking treatment planning computer output with measurements are confusing and fruitless, at times. Commissioning an IMRT program and routine patient dose verification of IMRT require films and ionization chamber measurements in phantom. Additional specialized physics instrumentation is not required other than those available in a typical radiation oncology facility. At this time, we consider that routine quality assurance prior to patient treatments is necessary.


Assuntos
Radioterapia Conformacional/métodos , Humanos , Doses de Radiação , Software
2.
Int J Radiat Oncol Biol Phys ; 45(2): 451-5, 1999 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10487570

RESUMO

PURPOSE: Although 8-10 Gy of external radiation therapy for +HIV associated parotid hypertrophy has achieved high response rates, the responses were transient with only 1/12 of patients retaining cosmetic control at median follow-up procedures of 9.5 months. Retreatment for failures after 8-10 Gy has also been unsatisfactory. Having shown that 24 Gy of external radiation therapy for benign parotid hypertrophy produced more durable cosmetic control than 8-10 Gy, we now report on longer follow-up periods on a group of patients receiving 24 Gy. MATERIALS AND METHODS: Twenty +HIV patients with clinical and radiographic evidence of lymphoepithelial lesions of the parotid were treated with 24 Gy of external radiation therapy using daily 1.5 Gy fractions; parallel opposed technique and 6 MV photons were used in 19 patients, and unilateral electron treatment was performed for one patient. RESULTS: With a mean follow-up period of 24 months, the cosmetic control appears durable. We have had no late failures past 24 months. Two patients have complained of modest xerostomia. There was no correlation with size of the cyst and eventual cosmetic result. CONCLUSIONS: Twenty-four Gy produces durable parotid control for HIV associated lymphoepithelial lesions of the parotid glands in +HIV patients. Failures after 2 years are uncommon and the side effects have been tolerable.


Assuntos
Infecções por HIV/complicações , Glândula Parótida/patologia , Feminino , Seguimentos , Humanos , Hipertrofia/radioterapia , Imageamento por Ressonância Magnética , Masculino , Dosagem Radioterapêutica , Falha de Tratamento , Xerostomia/etiologia
3.
Int J Radiat Oncol Biol Phys ; 43(2): 423-30, 1999 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-10030271

RESUMO

PURPOSE/OBJECTIVE: To investigate the effect of the enforced expression of p29Bcl-xL or its loop deletional mutant, p18Bcl-xLdelta, on irradiation-induced apoptosis and cell-cycle distribution of HL-60 cells. MATERIALS & METHODS: We compared the irradiation-induced molecular cascade of apoptosis in control human AML HL-60/neo versus Bcl-xL overexpressing (approximately 8-fold) (HL-60/Bcl-xL) and HL-60/Bcl-XLdelta cells that express the loop domain deletional mutant construct (delta26-83 AA) of Bcl-xL. The three cell lines were irradiated with 6MV photons to varying doses up to 20 Gy. Following this, cytosolic cyt c levels, caspase-3 activity, and the Bcl-2 family of proteins were evaluated utilizing Western blot analysis (whole cell lysate or cytosolic S-100 fraction). Apoptosis was assessed by internucleosomal DNA fragmentation, Annexin-V staining and FACS analysis, as well as by morphologic criteria. The cell-cycle effects of radiation were analyzed by flow cytometry. RESULTS: Eight hours following irradiation (12 Gy) of HL-60/neo cells, a marked increase (approximately 8-fold) in the cytosolic accumulation of cyt c in the S-100 fraction was observed. This was associated with the cleavage of caspase-3, as well as the generation of its poly (ADP-ribose) polymerase (PARP) and DFF (DNA fragmentation factor)-45 cleavage activity. Twenty-four to forty-eight hours after irradiation, internucleosomal DNA fragmentation and positive Annexin-V staining (32.3+/-3.3%) was detected in HL-60/neo cells. In contrast, in both HL-60/Bcl-xL and HL-60/Bcl-xLdelta cells, a significantly lower percentage of apoptotic cells (p<0.05) were detected and internucleosomal DNA fragmentation was not induced. Following irradiation, Western analysis neither demonstrated any significant alteration in Bcl-2, p29Bcl-xL, p18Bcl-xLdelta, or Bax; nor induced CD95 (Fas receptor) or Fas ligand expression in any cell type. However, in all cell types, irradiation produced approximately a 2-fold increase in the percentage of cells in the G2/M phase of the cell cycle. CONCLUSION: These results demonstrate that an intact loop domain is not necessary for the full antiapoptotic function of Bcl-xL against irradiation-induced cytosolic accumulation of cyt c, caspase activation, and apoptosis of HL-60 cells. Additionally, the cell-cycle effects of ionizing radiation in HL-60 cells are not affected by enforced expression of Bcl-xL or Bcl-xLdelta.


Assuntos
Apoptose/fisiologia , Caspases/metabolismo , Grupo dos Citocromos c/metabolismo , Citosol/enzimologia , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Proteínas Proto-Oncogênicas/metabolismo , Caspase 3 , Fase G2 , Células HL-60/efeitos da radiação , Sequências Hélice-Alça-Hélice , Humanos , Mitose , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteína X Associada a bcl-2 , Proteína bcl-X
4.
Radiology ; 201(1): 271-3, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8816557

RESUMO

PURPOSE: To demonstrate the variable location of biliary tree components and to assess two treatment planning rules of thumb used for locating porta hepatic nodes for radiation therapy. MATERIALS AND METHODS: The distance of the common hepatic duct bifurcation and duodenal papilla from adjacent vertebral bodies was measured on 34 cholangiograms, and their relationships to particular vertebral body levels were recorded. Adequacy of treatment volume to encompass porta hepatic lymph nodes was evaluated in 30 of these cholangiograms by constructing radiation portals according to the two rules of thumb. RESULTS: Location of the common hepatic duct bifurcation and duodenal papilla varied widely. The treatment portal encompassed 13% (four of 30) of cases when the first rule of thumb was used and 80% (24 of 30) of cases when the second rule of thumb was used. CONCLUSION: The wide variability of location of extrahepatic biliary tree structures suggests the need for individualized treatment planning so that sensitive and dose-limiting healthy tissues can be optimally excluded from radiation treatment portals. Computed tomography and other imaging modalities enable precise location of biliary tree components for radiation treatment planning.


Assuntos
Ampola Hepatopancreática/anatomia & histologia , Ducto Hepático Comum/anatomia & histologia , Ampola Hepatopancreática/diagnóstico por imagem , Colangiocarcinoma/diagnóstico por imagem , Colangiografia , Neoplasias do Sistema Digestório/radioterapia , Ducto Hepático Comum/diagnóstico por imagem , Humanos , Fígado/anatomia & histologia , Fígado/diagnóstico por imagem , Vértebras Lombares/anatomia & histologia , Vértebras Lombares/diagnóstico por imagem , Planejamento da Radioterapia Assistida por Computador , Vértebras Torácicas/anatomia & histologia , Vértebras Torácicas/diagnóstico por imagem
5.
Med Phys ; 23(10): 1809-14, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8946378

RESUMO

A method was devised to simulate patients with breast cancer in the actual treatment position utilizing a diagnostic CT spiral scanner, 3-D Image Workstation for virtual simulation, and a laser coordinate system to transfer planning parameters to the patient's skin. It was desired to produce non-divergent tangential beams through the lung as well as a matched line for tangential and supraclavicular fields. The patients were immobilized in an Alpha CradleTM cast. Radio-opaque markers were placed on the superior, inferior, medial, and lateral margins of the field so as to afford appropriate initial field set-up approximations. The patient was scanned. The data set was then transferred to the workstation where an isocenter was chosen. The patient was marked. Virtual simulation was then performed. This method employed a half beam technique for the posterior edge of the tangential fields. Table rotation and blocking of the superior margin of the tangential fields were used to produce a vertical edge to match a supraclavicular field. Using a beam's eye view the lateral tangent was matched to the medial exit. A digitally reconstructed radiograph was created to define the tangent fields and place the supraclavicular block. Our initial experience with 50 patients verifies that this is a reproducible and accurate technique. Time required for immobilization and tangential field simulation is approximately 30 minutes. Data is available for 3-D treatment planning or 2-D treatment planning on a reconstructed transverse slice angled to match the collimator angle through the patient. Using a CT simulator for simulation of breast cancer affords accuracy of at least equal magnitude to conventional simulators as determined by beam films and ease of set-up. This technique also affords greater ease in changing treatment parameters without having to resimulate the patient.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X , Simulação por Computador , Feminino , Humanos , Imagens de Fantasmas , Planejamento da Radioterapia Assistida por Computador/instrumentação , Radioterapia Assistida por Computador/instrumentação , Reprodutibilidade dos Testes
7.
Radiology ; 196(1): 275-80, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7784581

RESUMO

PURPOSE: To evaluate retrospectively the role of radiation therapy for extrahepatic bile duct (EHBD) carcinoma. MATERIALS AND METHODS: Twenty-seven patients with local-regional EHBD carcinomas were treated with definitive radiation therapy. Radiation therapy was delivered by means of external beam radiation therapy (EBRT) alone or combined with transcatheter iridium-192 brachytherapy. The median total dose was 54 Gy (range, 30-144 Gy). Survival rates were calculated and compared by using the log-rank test. Possible prognostic factors affecting survival were evaluated by means of univariate analysis. RESULTS: The median survival of all patients was 13 months, with 1- and 2-year actuarial survival rates of 52% and 10%, respectively. Univariate analysis revealed that men, patients with tumors limited to the bile duct, and patients receiving EBRT doses of at least 45 Gy had significantly better outcomes. Local-regional recurrence was the main cause of treatment failure (82%). Two patients developed gastric outlet obstruction. CONCLUSION: Patients with locally advanced EHBD carcinomas have a low survival rate. Certain factors, however, appear to have prognostic significance.


Assuntos
Adenocarcinoma/radioterapia , Neoplasias dos Ductos Biliares/radioterapia , Ductos Biliares Extra-Hepáticos , Adenocarcinoma/mortalidade , Adulto , Idoso , Neoplasias dos Ductos Biliares/mortalidade , Braquiterapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Prognóstico , Dosagem Radioterapêutica , Estudos Retrospectivos , Taxa de Sobrevida
8.
J Natl Med Assoc ; 87(7): 500-4, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7636896

RESUMO

The compliance with a program of breast-conservation treatment for early-stage breast cancer and the results of that treatment among women treated between January 1983 and January 1992 was investigated in a large inner-city public hospital serving a primarily black population. Medical records and charts were reviewed for 25 consecutive patients with stage I and II breast cancer seen in consultation in the radiation oncology department. Of those 25 patients, 20 underwent lumpectomy and radiation therapy. Survival, disease-free survival, and local recurrence-free survival were computed using the Kaplan-Meier method. Compliance was evaluated based on time to complete the prescribed course of radiotherapy after a lumpectomy. Five-year local recurrence-free survival for stage I and II patients was 95% (confidence interval [CI]: 71% to 99%). Five-year overall survival for stage II patients was 71% (CI: 31% to 92%), and disease-free survival was 74% (CI: 36% to 91%). This study demonstrates that a program of breast-conservation treatment for early-stage breast cancer can be implemented with good results, excellent treatment compliance, and 100% follow-up in a population of medically indigent women.


Assuntos
Neoplasias da Mama/cirurgia , Indigência Médica , Adulto , Idoso , Idoso de 80 Anos ou mais , População Negra , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Quimioterapia Adjuvante , Terapia Combinada , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Mastectomia Segmentar , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Cooperação do Paciente , Estudos Retrospectivos , Taxa de Sobrevida , Saúde da População Urbana
9.
Int J Radiat Oncol Biol Phys ; 32(3): 599-604, 1995 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-7790244

RESUMO

PURPOSE: To compare the efficacy of fast-neutron radiotherapy with that of conventionally fractionated photon therapy in the management of patients with locally advanced squamous cell carcinoma of the head and neck. METHODS AND MATERIALS: Patients with Stage III or IV disease were randomized to receive either 20.4 Gy/12 fractions/4 weeks of neutrons or 70 Gy/35 fractions/7 weeks of photons (control). Between April 1986 and March 1991, 178 patients were entered, 169 of whom were eligible for analysis. The treatment arms were balanced for age, stage, and performance status, but not for primary site of origin. RESULTS: Complete response occurred in 70 and 52% with neutrons and photons, respectively (p = 0.006). Local regional failure at 3 years for all patients was 63% for neutrons and 68% for photons. Actuarial overall survival curves were virtually identical in both study arms, falling to 27% at 3 years. Acute toxicity was similar in the two arms, but late grade 3-5 toxicity was 40% with neutrons compared to 18% with photons (p = 0.008). CONCLUSION: Although the initial response rate was higher with neutrons, permanent local control and survival were not improved, and the incidence of late normal tissue toxicity was increased. As a result, fast-neutron therapy for advanced squamous cell carcinoma of the head and neck can only be recommended for patients in whom the logistic benefit of treatment in 12 sessions over 4 weeks outweighs the increased risk of late toxicity.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Nêutrons Rápidos/uso terapêutico , Neoplasias de Cabeça e Pescoço/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Análise de Sobrevida
10.
Head Neck ; 17(1): 31-5, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7533750

RESUMO

BACKGROUND: Multicystic benign lymphoepithelial lesions of the parotid gland (BLL) seen in patients with human immunodeficiency virus (HIV) can produce considerable cosmetic deformity as well as physical discomfort. We previously reported our preliminary results with low-dose radiotherapy in this disease, and all 8 patients were satisfied with the initial improvement in their appearance. We now report the long-term follow-up of those patients and additional patients. METHODS: Twelve HIV-positive patients with BLL were treated with 8-10 Gy of external radiation using 2-Gy daily fractions. Objective responses and subjective duration of patient-defined cosmetic control were recorded. RESULTS: All 12 patients (100%) had at least a 50% decrease in the size of their parotid masses. Five of 12 (42%) had a complete response and 7 (58%) had a partial response. Persisting complete response was achieved in only 1 patient, however, with relapse in the other 11 patients. Cosmetic palliation, as judged by the patients, was achieved for a median of 9.5 months. Eight patients were subsequently retreated with doses of 6-16 Gy (median and mode: 10 Gy). None (0%) of the 8 patients retreated achieved local control. CONCLUSIONS: Very low-dose radiation (8-10 Gy) provides reliable but temporary cosmetic palliation for BLL. Retreatment was unsatisfactory, and we are now investigating higher initial doses of radiation to prolong palliation and eliminate recurrences.


Assuntos
Soropositividade para HIV , Doenças Parotídeas/radioterapia , Complexo Relacionado com a AIDS/radioterapia , Adulto , Idoso , Cistos/patologia , Epitélio/patologia , Estética , Feminino , Seguimentos , Humanos , Hiperplasia , Tecido Linfoide/patologia , Masculino , Cuidados Paliativos , Dosagem Radioterapêutica , Indução de Remissão
11.
Int J Radiat Oncol Biol Phys ; 28(1): 47-54, 1994 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-8270459

RESUMO

PURPOSE: To evaluate the effectiveness of fast neutron radiation therapy in treatment of locally advanced carcinomas of the prostate. METHODS AND MATERIALS: From April 1986 to October 1990, 178 patients were entered on a prospective, multi-institutional randomized study of the NCI-sponsored Neutron Therapy Collaborative Working Group. This trial compared external beam photon irradiation (7000-7020 cGy) with external beam neutron irradiation (2040 ncGy) for patients with high-grade T2 or T3-4, N0-1, M0 adenocarcinomas of the prostate. Eighty-nine patients were randomized to each treatment. Six patients were subsequently judged to be ineligible, leaving 85 photon and 87 neutron randomized patients eligible for analysis. RESULTS: With a follow-up time ranging from 40 to 86 months (68 months median follow-up) the 5-year actuarial clinical local-regional failure rate for patients treated with neutrons was 11%, vs. 32% for photons (p < 0.01). Incorporating the results of routine posttreatment prostate biopsies, the resulting "histological" local-regional tumor failure rates were 13% for neutrons vs. 32% for photons (p = 0.01). To date, actuarial survival and cause-specific survival rates are statistically indistinguishable for the two patient cohorts, with 32% of the neutron-treated patient deaths and 41% of the photon-treated patient deaths caused by prostate cancer (p = n.s.). Prostate specific antigen (PSA) values were elevated in 17% of neutron-treated patients and 45% of photon-treated patients at 5 years (p < 0.001). Severe late complications of treatment were higher for the neutron-treated patients (11% vs. 3%), and were inversely correlated with the degree of neutron beam shaping available at the participating institutions. Neutron treatment delivery utilizing a fully rotational gantry and multileaf collimator did not result in an increase in severe late effects when compared to photon treatment. CONCLUSION: High energy fast neutron radiotherapy is safe and effective when adequate beam delivery systems and collimation are available, and it is significantly superior to external beam photon radiotherapy in the local-regional treatment of large prostate tumors.


Assuntos
Adenocarcinoma/radioterapia , Nêutrons Rápidos , Neoplasias da Próstata/radioterapia , Radioterapia de Alta Energia , Adenocarcinoma/epidemiologia , Adenocarcinoma/patologia , Nêutrons Rápidos/efeitos adversos , Seguimentos , Humanos , Masculino , Recidiva Local de Neoplasia/epidemiologia , Fótons , Estudos Prospectivos , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/patologia , Radioterapia de Alta Energia/efeitos adversos , Taxa de Sobrevida
12.
Int J Radiat Oncol Biol Phys ; 27(3): 499-505, 1993 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-8226141

RESUMO

PURPOSE: To determine, with a prospective, multicenter randomized study, whether fast neutron radiation therapy improves the outcome for patients with non-small cell lung cancer, as compared to conventional photon radiotherapy. METHODS AND MATERIALS: From September 1986 to March 1991, a total of 200 patients with inoperable regional non-small cell lung cancer were randomized to 20.4 Gy in 12 fractions with neutrons versus 66 Gy in 33 fractions with photons. Inoperable patients with Radiation Therapy Oncology Group Stages I, II, III, or IV(M0) disease, Karnofsky Performance Score > or = 70, and who had received no previous therapy for their non-small cell lung cancer were eligible for the study. Of the 200 patients randomized, a total of 193 patients, 99 on the neutron arm and 94 on the photon arm, were eligible for analysis. The two treatment groups were balanced with regards to prognostic factors. At the time of this analysis, the median at-risk follow-up was 33 months, with a minimum follow-up of 16 months. RESULTS: No difference in overall survival was observed; however, there was a statistically significant improvement in survival for patients with squamous cell histology (p = 0.02), and a trend toward improved survival for those with favorable prognostic factors (i.e., patients who were not T4, N3, and had no pleural effusion or weight loss > 5% from baseline) (p = 0.15), favoring the neutron-treated group. With the exception of skin and subcutaneous changes, acute and late toxicity was similar in both arms. CONCLUSION: In selected patients with inoperable regional non-small cell lung cancer (e.g., squamous cell histology, favorable prognostic factors), fast neutron irradiation provides a therapeutic benefit over conventional photon radiotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma de Células Escamosas/radioterapia , Nêutrons Rápidos/uso terapêutico , Neoplasias Pulmonares/radioterapia , Fótons/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma de Células Escamosas/mortalidade , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taxa de Sobrevida
13.
Int J Radiat Oncol Biol Phys ; 27(2): 235-40, 1993 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-8407397

RESUMO

PURPOSE: To compare the efficacy of fast neutron radiotherapy versus conventional photon and/or electron radiotherapy for unresectable, malignant salivary gland tumors a randomized clinical trial comparing was sponsored by the Radiation Therapy Oncology Group in the United States and the Medical Research Council in Great Britain. METHODS AND MATERIALS: Eligibility criteria included either inoperable primary or recurrent major or minor salivary gland tumors. Patients were stratified by surgical status (primary vs. recurrent), tumor size (less than or greater than 5 cm), and histology (squamous or malignant mixed versus other). After a total of 32 patients were entered onto this study, it appeared that the group receiving fast neutron radiotherapy had a significantly improved local/regional control rate and also a borderline improvement in survival and the study was stopped earlier than planned for ethical reasons. Twenty-five patients were study-eligible and analyzable. RESULTS: Ten-year follow-up data for this study is presented. On an actuarial basis, there continues to be a statistically-significant p = 0.009) but there is no improvement in overall survival (15% vs. 25%, p = n.s.). Patterns of failure are analyzed and it is shown that distant metastases account for the majority of failures on the neutron arm and local/regional failures account for the majority of failures on the photon arm. Long-term, treatment-related morbidity is analyzed and while the incidence of morbidity graded "severe" was greater on the neutron arm, there was no significant difference in "life-threatening" complications. This work is placed in the context of other series of malignant salivary gland tumors treated with definitive radiotherapy. CONCLUSIONS: Fast neutron radiotherapy appears to be the treatment-of-choice for patients with inoperable primary of recurrent malignant salivary gland tumors.


Assuntos
Nêutrons Rápidos/uso terapêutico , Fótons/uso terapêutico , Neoplasias das Glândulas Salivares/radioterapia , Adulto , Idoso , Seguimentos , Humanos , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Neoplasias das Glândulas Salivares/mortalidade , Fatores de Tempo
14.
Am J Clin Oncol ; 16(2): 164-7, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8452112

RESUMO

Between June 1977 and April 1983 the Radiation Therapy Oncology Group (RTOG) sponsored a Phase III randomized trial investigating the use of fast neutron radiotherapy for patients with locally advanced (Stages C and D1) adenocarcinoma of the prostate gland. Patients were randomized to receive either conventional photon radiation or fast neutron radiation used in a mixed-beam (neutron/photon) treatment schedule. A total of 91 analyzable patients were entered into the study, and the two patient groups were balanced with respect to the major prognostic variables. Actuarial curves are presented for local/regional control and "overall" survival. Ten-year results for clinically assessed local control are 70% for the mixed-beam group versus 58% for the photon group (p = 0.03) and for survival are 46% for the mixed-beam group versus 29% for the photon group (p = 0.04). This study suggests that a regional method of treatment can influence both local tumor control and survival in patients with locally advanced adenocarcinoma of the prostate gland.


Assuntos
Adenocarcinoma/radioterapia , Adenocarcinoma/secundário , Neoplasias da Próstata/radioterapia , Nêutrons Rápidos , Humanos , Masculino , Radioterapia/métodos , Análise de Sobrevida
15.
Cancer ; 71(4): 1362-7, 1993 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-8435812

RESUMO

BACKGROUND: Although there have been occasional reports of improved response with greater doses of irradiation for unresected brain metastases, dose escalation has not been systematically studied in a cohort of patients with solitary brain metastasis. The current study examines this group of patients to evaluate dose escalation using accelerated hyperfractionated radiation therapy (XRT) with regard to survival, patterns of failure, and toxicity. METHOD: Radiation Therapy Oncology Group (RTOG) 85-28, a Phase I/II randomized trial of accelerated hyperfractionated XRT for patients with unresected supratentorial brain metastases, enrolled 153 patients with solitary brain metastasis. Whole brain dose was 32 Gray (Gy) administered in 1.6 Gy fractions twice a day with an interfraction interval of 4-8 hours. Boost dose was escalated to total doses of 48.0, 54.4, 64.0, and 70.4 Gy. RESULTS: Acute and late toxicities were acceptable. The median survival time and 1-year survival rates were 4.9 months and 20% at 48 Gy; 5.4 months and 33% at 54.4 Gy; 7.2 months and 28% at 64 Gy; and 8.2 months and 37% at 70.4 Gy, respectively. Comparison of the upper three dose treatment arms to the 48 Gy treatment arm revealed a superior survival time with doses of 54.4 Gy and greater (P = 0.05). Improvement in neurologic function appeared to increase with dose escalation, with 25% of patients experiencing improvement at doses of 48 Gy, 38% at 54.4 Gy, 50% at 64 Gy, and 63% at 70.4 Gy (P = not significant). CONCLUSION: A radiation dose response for survival time appears to exist with the use of accelerated hyperfractionated XRT for patients with unresected solitary brain metastasis.


Assuntos
Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Dosagem Radioterapêutica , Adenocarcinoma/patologia , Adenocarcinoma/radioterapia , Adenocarcinoma/secundário , Adulto , Idoso , Encéfalo/efeitos da radiação , Carcinoma/patologia , Carcinoma/radioterapia , Carcinoma/secundário , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/secundário , Estudos de Coortes , Relação Dose-Resposta à Radiação , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Taxa de Sobrevida , Falha de Tratamento
16.
Int J Radiat Oncol Biol Phys ; 22(3): 569-71, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1531215

RESUMO

In a Phase II study of etanidazole (SR 2508), the dose of 17 x 2 g/m2 (total drug dose: 34 g/m2) was tested in 33 patients and the toxicity was deemed acceptable. A Phase III trial is now in progress comparing conventional radiotherapy with conventional radiotherapy plus etandizole (2 g/m2 i.v. 30 to 60 min before radiotherapy each Monday, Wednesday, and Friday to 34 g/m2 in 17 doses) in patients with unresectable head and neck carcinomas. A recent analysis showed only 14.7% grade 1 and 3.9% Grade 2 peripheral neuropathy. In the initial study design, 133 evaluable patients per treatment arm could achieve an 80% level of power of detecting a 15% difference in local-regional control rates between the radiotherapy arm (25% local-regional control at 2 years) and the radiotherapy plus etanidazole arm (assuming a 40% rate). Allowing for 20 ineligible cases in each arm, a total number of 306 was required. An interim analysis showed that 27% of the patients assigned to radiotherapy plus etanidazole are receiving less than 14 doses of the drug. It is assumed that less than 14 drug doses will not produce any therapeutic gain, therefore, a true 40% local-regional control rate in the radiotherapy plus etanidazole arm will be observed as a 36% rate when analyzed by assigned treatment. Using this information, the study was modified to have an 80% level of power in detecting a difference between a 25% local-regional control rate in the radiotherapy group and a 36% rate in the radiotherapy plus etanidazole group. Allowing for a 10% patient ineligibility rate, 518 patients are required. With 12 patients entered per month, it is estimated that patient accrual to this study will continue through October 1991.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/radioterapia , Nitroimidazóis/uso terapêutico , Radiossensibilizantes/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Terapia Combinada , Etanidazol , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Nitroimidazóis/efeitos adversos , Nitroimidazóis/farmacocinética , Radiossensibilizantes/efeitos adversos , Radiossensibilizantes/farmacocinética , Projetos de Pesquisa
17.
Int J Radiat Oncol Biol Phys ; 21(3): 549-56, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1869453

RESUMO

A retrospective analysis of the effect of local control on the development of distant metastases was performed in 2648 patients with carcinoma of the head and neck selected from the RTOG database. The 5-year time-adjusted incidence of distant metastases was 21% for patients who were in local-regional control at 6 months after the start of treatment, compared to 38% for local-regional failure patients (p less than 0.001). The incidence of distant metastases detected between the interval of 6 months to 2.5 years after treatment was significantly increased in patients with tumors of the oral cavity, oropharynx, supraglottic larynx, and glottis who developed local-regional failure within this time period, compared to those who remained locally controlled (19% distant metastases for local-regional failure vs 7% for local-regional control (p less than 0.001)). In contrast, there as no difference in the incidence of distant metastases in patients with carcinoma of the nasopharynx or hypopharynx regardless of the local-regional disease status. A Cox proportional hazards regression analysis demonstrated that local-regional control was the most significant variable affecting the development of distant metastases, followed by tumor site, N-stage, and T-stage. For all tumor sites, except for the hypopharynx and nasopharynx, improvements in local-regional control are likely to improve survival. Tumors of the hypopharynx and nasopharynx have a higher probability of micro-metastatic dissemination at the time of initial diagnosis, and until effective methods to treat disseminated disease are developed, the effect of local control on survival will not be readily discerned.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/radioterapia , Metástase Neoplásica/patologia , Recidiva Local de Neoplasia/patologia , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/epidemiologia , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Recidiva Local de Neoplasia/epidemiologia , Modelos de Riscos Proporcionais , Estudos Retrospectivos
18.
Int J Radiat Oncol Biol Phys ; 20(1): 13-20, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1993621

RESUMO

For all randomized trials since 1978, the Radiation Therapy Oncology Group has required the study chairman for radiation therapy to review the treatment given to each patient. The chairman scores the compliance of the treatment borders, total dose, fraction, and total elapsed time relative to the protocol prescription at the primary site, regional nodes, and any critical structure. The individual parameters are then considered together to derive an "overall" treatment score. For two RTOG head and neck studies in patients with moderately and very advanced carcinomas, the "overall" treatment was classified as unacceptable if the treatment at primary was scored unacceptable with respect to dose, fractionation, and field borders. However, prolonged elapsed treatment was not included. Analysis of these studies with 426 evaluable patients was performed to assess the relationship of unacceptable "overall" treatment compliance with outcome. Patients with prolonged treatment elapsed days (14 days beyond the protocol prescription) exhibited significantly poorer loco-regional control (13% vs. 27% at 3 years with p = .007) and absolute survival (13% vs. 26% at 3 years with p = .01). As a result, the criteria for unacceptable "overall" treatment were revised to include prolonged elapsed treatment days. Further multivariate analyses showed the revised criteria identified patients with significantly poorer loco-regional control and absolute survival even after adjusting for other prognostic factors.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Ensaios Clínicos como Assunto/normas , Neoplasias de Cabeça e Pescoço/radioterapia , Carcinoma de Células Escamosas/tratamento farmacológico , Protocolos Clínicos , Terapia Combinada , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Misonidazol/uso terapêutico , Avaliação de Processos e Resultados em Cuidados de Saúde/normas , Radiossensibilizantes/uso terapêutico
19.
Int J Radiat Oncol Biol Phys ; 20(1): 21-8, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1993628

RESUMO

This is a report of a 10-year median follow-up of a randomized, prospective study investigating the optimal sequencing of radiation therapy (RT) in relation to surgery for operable advanced head and neck cancer. In May 1973, the Radiation Therapy Oncology Group (RTOG) began a Phase III study of preoperative radiation therapy (50.0 Gy) versus postoperative radiation therapy (60.0 Gy) for supraglottic larynx and hypopharynx primaries. Of 277 evaluable patients, duration of follow-up is 9-15 years, with 7.6% patients lost to follow-up before 7 years. Loco-regional control was significantly better for 141 postoperative radiation therapy patients than for 136 preoperative radiation therapy patients (p = 0.04), but absolute survival was not affected (p = 0.15). When the analysis was restricted to supraglottic larynx primaries (60 postoperative radiation therapy patients versus 58 preoperative radiation therapy patients), the difference for loco-regional control was highly significant (p = .007), but not for survival (p = 0.18). In considering only supraglottic larynx, 78% of loco-regional failures occurred in the first 2 years. Thirty-one percent (18/58) of preoperative patients failed locally within 2 years versus 18% (11/60) of postoperative patients. After 2 years, distant metastases and second primaries became the predominant failure pattern, especially in postoperative radiation therapy patients. This shift in the late failure pattern along with the increased number of unrelated deaths negated any advantage in absolute survival for postoperative radiation therapy patients. The rates of severe surgical and radiation therapy complications were similar between the two arms. Because of an increased incidence of late distant metastases and secondary primaries, additional therapeutic intervention is required beyond surgery and postoperative irradiation to impact significantly upon survival.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/radioterapia , Adulto , Idoso , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/cirurgia , Terapia Combinada , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/epidemiologia , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Cuidados Pré-Operatórios , Estudos Prospectivos
20.
Radiother Oncol ; 19(4): 307-16, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2126633

RESUMO

Five hundred and fifty patients were entered into a set of dose-searching studies designed to determine normal tissue tolerance to high energy (42-66 MeV reactions) fast neutrons delivered in 12 equal fractions over 4 weeks. Participating institutions included: The Fermilab (66 MeV p+----Be), The University of Washington (50 MeVp+----Be), U.C.L.A. (45 MeVH-----Be), M.D. Anderson Hospital (42 MeVH-----Be), and The Cleveland Clinic (42 MeVp+----Be). Patients were stratified by treatment facility and then randomized to receive 16, 18 or 20 Gy for tumors located in the upper abdomen or pelvis, and 18, 20 or 22 Gy for tumors located in the head and neck, thorax or extremities. Following completion of the randomized protocols, additional patients were studied at the 20.4 Gy level in the head and neck, thorax and pelvis. Normal tissue effect scoring was accomplished using the RTOG-EORTC acute and late normal tissue effect scales. Acute Grade 3 + toxicity rates in the head and neck were 19% for 20/20.4 Gy and 20% for 22 Gy. Time adjusted late toxicity rates in the head and neck at 12 months were 15% for 20/20.4 Gy and 0% for 22 Gy. The 18 Gy treatment arm of the head and neck protocol was dropped early in the study after only two patients were accrued. For cases treated in the thorax, acute Grade 3 + toxicity rates were 6% for 18 Gy, 15% for 20/20.4 Gy and 7% for 22 Gy. Late toxicity rates at 12 months were 0% for 18 Gy, 11% for 20/20.4 Gy and 18% for 22 Gy. Acute Grade 3+ toxicity rates in the upper abdomen were 0% for 16 Gy, 8% for 18 Gy and 12% for 20 Gy. There were no Grade 3 + late toxicities in the upper abdomen. In the pelvis, acute Grade 3 + toxicity rates were 0% for 16 Gy, 3% for 18 Gy and 3% for 20/20.4 Gy. Late Grade 3 + toxicities at 24 months were 20% for 16 Gy, 5% for 18 Gy and 24% for 20/20.4 Gy. In extremities, acute Grade 3 + toxicity rates were 7% for 20 Gy and 21% for 22 Gy while at 12 months, late Grade 3 + toxicity rates were 14 and 35%, respectively. The 18 Gy treatment arm of the extremities protocol was dropped early in the study after only two patients were accrued. Factors associated with normal tissue effects in addition to treatment dose are discussed.


Assuntos
Neoplasias Abdominais/radioterapia , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias Pélvicas/radioterapia , Dosagem Radioterapêutica , Radioterapia de Alta Energia , Neoplasias Torácicas/radioterapia , Relação Dose-Resposta à Radiação , Extremidades/efeitos da radiação , Nêutrons Rápidos/uso terapêutico , Seguimentos , Humanos , Enteropatias/etiologia , Pneumonia/etiologia , Lesões por Radiação/etiologia , Tolerância a Radiação , Radioterapia de Alta Energia/efeitos adversos , Distribuição Aleatória , Dermatopatias/etiologia , Doenças da Bexiga Urinária/etiologia
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