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2.
Radiother Oncol ; 104(2): 263-6, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22857860

RESUMO

PURPOSE: To provide practice guidelines for delineating clinical target volume (CTV) for radiotherapy planning of non melanoma (NMSC) skin cancers. METHODS AND MATERIALS: A prospective, single arm, study. Preoperatively, a radiation oncologist outlined the boundary of a gross lesion, and drew 5-mm incremental marks in four directions from the delineated border. Under local anesthesia, the lesion was excised, and resection margins were assessed microscopically by frozen section. Once resection margins were clear, the microscopic tumor extent was calculated using the presurgical incremental markings as references. A potential relationship between the distance of microscopic tumor extension and other variables was analyzed. RESULTS: A total of 159 lesions in 150 consecutive patients, selected for surgical excision with frozen section assisted assessment of resection margins, were accrued. The distance of microscopic tumor extension beyond a gross lesion varied from 1mm to 15 mm, with a mean of 5.3mm. The microscopic tumor extent was positively correlated with the size of gross lesion, histology and number of surgical attempts required to obtain a clear margin. To provide a 95% or greater chance of covering microscopic disease we make the following recommendations for CTV margins; 10mm for BCC less than 2 cm, 13 mm for BCC greater than 2 cm, 11 mm for SCC less than 2 cm, and 14 mm for SCC greater than 2 cm. CONCLUSIONS: Tumors greater than 2 cm and SCC histology required larger margins to adequately cover the microscopic extent of disease. This information is crucial in radiation planning of NMSC. Clinicians should be cautioned, as these guidelines may not offer optimum treatment for patients with extremely large or small lesions.


Assuntos
Carcinoma Basocelular/radioterapia , Carcinoma de Células Escamosas/radioterapia , Guias de Prática Clínica como Assunto , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Carcinoma Basocelular/patologia , Carcinoma Basocelular/cirurgia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Estudos de Coortes , Feminino , Seguimentos , Secções Congeladas , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Células Neoplásicas Circulantes/patologia , Células Neoplásicas Circulantes/efeitos da radiação , Estudos Prospectivos , Medição de Risco , Neoplasias Cutâneas/cirurgia , Resultado do Tratamento , Carga Tumoral/efeitos da radiação
3.
Int J Radiat Oncol Biol Phys ; 65(1): 52-8, 2006 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-16457966

RESUMO

PURPOSE: Recent reports demonstrate a dramatically increased rate of secondary leukemia for breast cancer patients receiving adjuvant high-dose anthracycline and radiotherapy, and that radiation is an independent factor for the development of leukemia. This study aimed to evaluate the radiation body exposure during breast radiotherapy and to characterize the factors associated with an increased exposure. PATIENTS AND METHODS: In a prospective cohort of 120 women, radiation measurements were taken from four sites on the body at the time of adjuvant breast radiotherapy. Multiple regression analysis was performed to analyze patient and treatment factors associated with the amount of scattered radiation. RESULTS: For standard 50 Gy breast radiotherapy, the minimal dose received by abdominal organs is on average 0.45 Gy, ranging from 0.06 to 1.55 Gy. The use of physical wedges as a compensation technique was the most significant factor associated with increased scattered dose (p < 0.001), resulting in approximately three times more exposure compared with breast intensity-modulated radiation therapy (IMRT) and dynamic wedge. CONCLUSIONS: The amount of radiation that is scattered to a patient's body is consistent with exposure reported to be associated with excess of leukemia. In accordance with the As Low As Reasonably Achievable (ALARA) principle, we recommend using breast IMRT or virtual wedging for the radiotherapy of breast cancer receiving high-dose anthracycline chemotherapy.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/radioterapia , Leucemia Induzida por Radiação/etiologia , Radioterapia Adjuvante/efeitos adversos , Radioterapia de Intensidade Modulada , Espalhamento de Radiação , Estatura , Peso Corporal , Feminino , Humanos , Estudos Prospectivos , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Análise de Regressão
4.
Nat Clin Pract Oncol ; 2(4): 211-7, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16264936

RESUMO

Intensity-modulated radiation therapy (IMRT) is a novel form of radiotherapy, which has the potential to reduce the amount of radiation unintentionally delivered to normal tissues while maintaining a high radiation dose to the tumor in comparison with standard radiation techniques. In adults, this technology has been implemented in a number of tumor sites, but in children it has been little used. This article will review the current studies in which IMRT has been used in children. It will also discuss possible future applications for IMRT, and anticipated problems with its use.


Assuntos
Neoplasias/radioterapia , Radioterapia Conformacional , Criança , Humanos
5.
Med Dosim ; 30(3): 149-54, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16112466

RESUMO

Breast intensity-modulated radiation therapy (IMRT) improves dose distribution homogeneity within the whole breast. Previous publications report the use of inverse or forward dose optimization algorithms. Because the inverse technique is not widely available in commercial treatment planning systems, it is important to compare the 2 algorithms. The goal of this work is to compare them on a prospective cohort of 30 patients. Dose distributions were evaluated on differential dose-volume histograms using the volumes receiving more than 105% (V(105)) and 110% (V(110)) of the prescribed dose, and on the maximum dose (D(max)) or hot spot and the sagittal dose gradient (SDG) being the gradient between the dose on inframammary crease and the dose prescribed. The data were analyzed using Wilcoxon signed rank test. The inverse planning significantly improves the V(105) (mean value 9.7% vs. 14.5%, p=0.002), and the V(110) (mean value 1.4% vs. 3.2%, p=0.006). However, the SDG is not statistically significantly different for either algorithm. Looking at the potential impact on skin acute reaction, although there is a significant reduction of V(110) using an inverse algorithm, it is unlikely this 1.6% volume reduction will present a significant clinical advantage over a forward algorithm. Both algorithms are equivalent in removing the hot spots on the inframammary fold, where acute skin reactions occur more frequently using a conventional wedge technique. Based on these results, we recommend that both forward and inverse algorithms should be considered for breast IMRT planning.


Assuntos
Neoplasias da Mama/radioterapia , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada/métodos , Algoritmos , Mama/efeitos da radiação , Feminino , Humanos , Dosagem Radioterapêutica
6.
Int J Radiat Oncol Biol Phys ; 62(4): 1096-9, 2005 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15990014

RESUMO

PURPOSE: To quantify the microscopic tumor extension beyond clinically delineated gross tumor boundary in nonmelanoma skin cancers. METHODS AND MATERIALS: A prospective, single arm, study. Preoperatively, a radiation oncologist outlined the boundary of a gross lesion, and drew 5-mm incremental marks in four directions from the delineated border. Under local anesthesia, the lesion was excised, and resection margins were assessed microscopically by frozen section. Once resection margins were clear, the microscopic tumor extent was calculated using the presurgical incremental markings as references. A potential relationship between the distance of microscopic tumor extension and other variables was analyzed. RESULTS: A total of 71 lesions in 64 consecutive patients, selected for surgical excision with frozen-section-assisted assessment of resection margins, were accrued. The distance of microscopic tumor extension beyond a gross lesion varied from 1 mm to 15 mm, with a mean of 5.2 mm. A margin of 10 mm was required to provide a 95% chance of obtaining clear resection margins. The microscopic tumor extent was positively correlated with the size of gross lesion, but not with other variables. CONCLUSIONS: The distance of microscopic tumor extension beyond a gross nonmelanoma skin cancer was variable, with a mean of 5.2 mm. Such information is critical for the proper radiation planning of skin cancer therapy.


Assuntos
Carcinoma Basocelular/patologia , Carcinoma de Células Escamosas/patologia , Neoplasias Cutâneas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Carcinoma Basocelular/cirurgia , Carcinoma de Células Escamosas/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Cutâneas/cirurgia
7.
Int J Radiat Oncol Biol Phys ; 62(3): 719-24, 2005 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15936551

RESUMO

PURPOSE: To examine the effect of 2-year androgen suppression (AS) on the pattern and extent of hemoglobin (Hb) change. METHODS AND MATERIALS: The basis of this report was a Phase II study evaluating a combined treatment of salvage radiotherapy plus 2-year AS for a rising prostate-specific antigen level after surgery. Patients had laboratory tests performed, including Hb and serum testosterone, and answered a quality-of-life questionnaire (European Organization for Research and Treatment of Cancer Quality-of-life Questionnaire 30 item) at regular intervals during the AS and post-AS period. The pattern and extent of the change in Hb was analyzed in relation to the testosterone level. The clinical significance of the Hb change was evaluated with a correlation analysis between Hb and the three specific domains of the questionnaire (Global Health Status, Physical Functioning, and Fatigue). RESULTS: Of a total of 74 accrued patients, 69 were identified as eligible for this report. The median patient age was 70 years. The median follow-up was 38.6 months. The mean Hb was 150.7 g/L at baseline and declined with radiotherapy by 5.9 g/L. The maximal Hb drop during AS was 16.0 g/L (p <0.0001), occurring at 16 months after the initiation of AS. Hb recovery in the post-AS period was slow. The decline and recovery of the mean Hb and hematocrit followed that of testosterone. The three quality-of-life domains did not show any significant correlation with the change in Hb. CONCLUSION: Two-year AS resulted in a statistically significant drop in the mean Hb, but had no clinically apparent adverse effect. The pattern of Hb change was similar to that of testosterone change.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Busserrelina/uso terapêutico , Hemoglobinas/metabolismo , Neoplasias da Próstata/sangue , Neoplasias da Próstata/terapia , Terapia de Salvação , Idoso , Fadiga , Nível de Saúde , Hematócrito , Humanos , Masculino , Prostatectomia , Qualidade de Vida , Testosterona/sangue
8.
Nutr Cancer ; 51(1): 32-6, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15749627

RESUMO

When local treatments for prostate cancer have failed, and prostate-specific antigen (PSA) rises in the absence of symptoms, there is little consensus as to the best management strategy. Calcitriol has been shown to prolong the doubling time of PSA in this context, but near-toxic doses are required. We investigated the effect of the nutrient vitamin D (cholecalciferol), a biochemical precursor of calcitriol, on PSA levels and the rate of rise of PSA in these patients. Fifteen patients were given 2,000 IU (50 microg) of cholecalciferol daily and monitored prospectively every 2-3 mo. In 9 patients, PSA levels decreased or remained unchanged after the commencement of cholecalciferol. This was sustained for as long as 21 mo. Also, there was a statistically significant decrease in the rate of PSA rise after administration of cholecalciferol (P = 0.005) compared with that before cholecalciferol. The median PSA doubling time increased from 14.3 mo prior to commencing cholecalciferol to 25 mo after commencing cholecalciferol. Fourteen of 15 patients had a prolongation of PSA doubling time after commencing cholecalciferol. There were no side effects reported by any patient. Further study is needed to confirm this finding and to explore the potential therapeutic benefit of nutrient vitamin D in prostate cancer.


Assuntos
Colecalciferol/uso terapêutico , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/tratamento farmacológico , Antígeno Prostático Específico/biossíntese , Neoplasias da Próstata/sangue , Neoplasias da Próstata/tratamento farmacológico , Administração Oral , Idoso , Calcitriol/metabolismo , Agonistas dos Canais de Cálcio/metabolismo , Colecalciferol/efeitos adversos , Colecalciferol/fisiologia , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Projetos Piloto , Estudos Prospectivos , Antígeno Prostático Específico/sangue , Prostatectomia , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia , Resultado do Tratamento
9.
Can J Urol ; 12(1): 2547-52, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15777493

RESUMO

PURPOSE: To examine the change of hemoglobin in relation to testosterone level in non-metastatic prostate cancer patients receiving 2-year androgen suppression. METHODS AND MATERIALS: A cohort of 72 patients, as participants of a phase II study, were treated with adjuvant radiotherapy plus 2-year androgen suppression after surgery to reduce the risk of relapse. Patients had laboratory tests including hemoglobin (Hb) and testosterone, and a quality of life questionnaire at regular intervals during the androgen suppression and post-androgen suppression period. The pattern of the change in Hb was evaluated in relation to testosterone level. The clinical significance of Hb change was assessed with a correlation analysis between Hb and the three domains of the questionnaire (global health status, physical functioning, and fatigue). RESULTS: Median age was 64.2 years. Median follow-up was 37 months. Mean Hb at the baseline was 148.4 g/L. It declined slightly with radiotherapy by 2.2 g/L. Maximal Hb decline during androgen suppression was 10.5 g/L (p < 0.0001), occurring at 24 months after the initiation of androgen suppression. In most patients, Hb decline was < 20 g/L. In the post-androgen suppression period, the recovery of Hb was slow and followed that of testosterone. The three quality of life domains did not show any significant correlation with the change in Hb. CONCLUSION: The decline and recovery of Hb was closely related to that of testosterone. Two-year androgen suppression resulted in a statistically significant decline of Hb, which had, however, no clinically apparent adverse effect on the three quality of life domains.


Assuntos
Anemia/etiologia , Antineoplásicos Hormonais/uso terapêutico , Hemoglobinas/metabolismo , Neoplasias da Próstata/sangue , Neoplasias da Próstata/terapia , Idoso , Antagonistas de Androgênios/uso terapêutico , Busserrelina/uso terapêutico , Ensaios Clínicos Fase II como Assunto , Humanos , Imidazolidinas/uso terapêutico , Masculino , Pessoa de Meia-Idade , Radioterapia Adjuvante , Perfil de Impacto da Doença , Testosterona/sangue
10.
Int J Radiat Oncol Biol Phys ; 61(3): 736-40, 2005 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-15708251

RESUMO

PURPOSE: To examine the long-term outcome and patterns of relapse in clinical Stage I testicular seminoma managed with surveillance alone after radical inguinal orchiectomy. METHODS AND MATERIALS: This was a prospective, single-arm study. Patients with Stage I testicular seminoma were treated with surveillance alone in accordance with regular, predefined, schedules and investigations. RESULTS: The study accrued a total of 88 patients between 1985 and 1996. The median age at diagnosis was 34 years. The median tumor size was 3.5 cm. The median follow-up as of June 2003 was 12.1 years. Only 3 patients were lost to follow-up. Of the 88 patients, 71 remained free of relapse and 17 did not. The actuarial relapse-free rate was 83%, 80%, and 80% at 5, 10, and 15 years, respectively. Most relapses (15 of 17) were below the diaphragm. Of the 17 patients with relapse, 14 were treated with radiotherapy and 3 with combination chemotherapy. Only 1 had a second relapse and was further salvaged by chemotherapy. All 17 relapsed patients remained free of recurrence after salvage treatment. None died of seminoma. The statistically significant predictive factor for relapse on the Cox proportional hazards model was the presence of rete testis invasion (hazard ratio 3.5, p = 0.03). CONCLUSION: Surveillance with the reservation of radiotherapy or chemotherapy for salvage of relapse is a safe alternative to upfront postoperative adjuvant therapy for Stage I testicular seminoma.


Assuntos
Seminoma/cirurgia , Neoplasias Testiculares/cirurgia , Adulto , Idoso , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Orquiectomia , Modelos de Riscos Proporcionais , Estudos Prospectivos , Recidiva , Terapia de Salvação , Seminoma/tratamento farmacológico , Seminoma/secundário , Neoplasias Testiculares/tratamento farmacológico , Neoplasias Testiculares/patologia , Resultado do Tratamento
11.
Can J Urol ; 11(5): 2390-2, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15576004

RESUMO

Breast and prostate cancer occurring concurrently is a rare occurrence. However, the recent literature has reported that there is an increased incidence of male breast cancer in prostate cancer patients. The authors describe the case of a man who presented with breast cancer, which was preceded by prostate cancer. There are some common features in terms of the etiology, diagnosis and treatment of these two tumors which are discussed.


Assuntos
Neoplasias da Mama Masculina/patologia , Neoplasias Primárias Múltiplas/patologia , Neoplasias da Próstata/patologia , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino
12.
J Oral Maxillofac Surg ; 62(9 Suppl 2): 120-2, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15332189

RESUMO

PURPOSE: This is a report of a technique of cranial bone harvesting suitable for the outpatient setting. MATERIALS AND METHODS: Bone scrapers are used for the harvesting of cranial bone shavings with the patient under intravenous sedation or general anesthesia. RESULTS: Graft volumes larger than that usually obtainable from intraoral sites and the tibia have been harvested utilizing this technique. In a series of 8 first patients, the largest volume of bone obtained was 14 cc with no complications related to the donor sites. These cases include the following types of pre-implant reconstructive procedures: large unilateral sinus grafting, bilateral sinus grafting/guided-bone regeneration of an entire alveolar ridge, inlay grafting of the alveolus, inlay grafting in association with distraction osteogenesis, subnasal grafting, alveolar cleft grafting, closure of large oroantral defects combined with sinus grafting, and grafting of an grossly atrophic mandible with simultaneous placement of dental implants via the submental approach. CONCLUSION: This is a safe bone harvesting technique providing an alternative source of autogenous bone graft.


Assuntos
Procedimentos Cirúrgicos Ambulatórios/métodos , Transplante Ósseo , Coleta de Tecidos e Órgãos/métodos , Aumento do Rebordo Alveolar , Anestesia Intravenosa , Atrofia , Sedação Consciente , Implantes Dentários , Regeneração Tecidual Guiada Periodontal , Humanos , Mandíbula/cirurgia , Maxila/cirurgia , Seio Maxilar/cirurgia , Fístula Bucoantral/cirurgia , Osteogênese por Distração , Crânio , Transplante Autólogo
13.
Australas Radiol ; 48(2): 181-7, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15230752

RESUMO

With the emergence of new imaging and implant techniques, prostate brachytherapy has become increasingly popular over the last decade. Brachytherapy promises to deliver twice the biologically effective dose as conventional external beam treatments without increasing the dose to tissues surrounding the prostate. However, there are few or no published Australian series of its efficacy in the clinic. We present the experience of one of the first centres in Australia to offer this service to its patients: a series from Sir Charles Gairdner Hospital in Western Australia. We present data on the efficacy of brachytherapy in maintaining prostate specific antigen levels, as well as the rate of urinary, rectal and sexual complications. Our results compare favourably with other brachytherapy and external beam treatment series. We believe that with the increasing trend towards dose escalation and novel therapies, standardized measurements of success and failure need to be better defined, and that randomized trials comparing modalities are needed to improve the management of prostate cancer.


Assuntos
Braquiterapia/métodos , Radioisótopos do Iodo/uso terapêutico , Neoplasias da Próstata/radioterapia , Idoso , Braquiterapia/efeitos adversos , Humanos , Masculino , Antígeno Prostático Específico/sangue , Resultado do Tratamento , Austrália Ocidental
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