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1.
Med Dosim ; 30(1): 20-4, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15749007

RESUMO

Computed tomgoraphy-magnetic resonance imaging (CT-MRI) registrations are routinely used for target-volume delineation of brain tumors. We clinically use 2 software packages based on manual operation and 1 automated package with 2 different algorithms: chamfer matching using bony structures, and mutual information using intensity patterns. In all registration algorithms, a minimum of 3 pairs of identical anatomical and preferably noncoplanar landmarks is used on each of the 2 image sets. In manual registration, the program registers these points and links the image sets using a 3-dimensional (3D) transformation. In automated registration, the 3 landmarks are used as an initial starting point and further processing is done to complete the registration. Using our registration packages, registration of CT and MRI was performed on 10 patients. We scored the results of each registration set based on the amount of time spent, the accuracy reported by the software, and a final evaluation. We evaluated each software program by measuring the residual error between "matched" points on the right and left globes and the posterior fossa for fused image slices. In general, manual registration showed higher misalignment between corresponding points compared to automated registration using intensity matching. This error had no directional dependence and was, most of the time, larger for a larger structure in both registration techniques. Automated algorithm based on intensity matching also gave the best results in terms of registration accuracy, irrespective of whether or not the initial landmarks were chosen carefully, when compared to that done using bone matching algorithm. Intensity-matching algorithm required the least amount of user-time and provided better accuracy.


Assuntos
Neoplasias Encefálicas/patologia , Imageamento por Ressonância Magnética , Planejamento da Radioterapia Assistida por Computador , Tomografia Computadorizada por Raios X , Algoritmos , Neoplasias Encefálicas/radioterapia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Software
2.
Int J Radiat Oncol Biol Phys ; 58(1): 233-40, 2004 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-14697443

RESUMO

PURPOSE: To determine the 15-year outcomes for women with early stage breast cancer after breast conservation therapy. METHODS AND MATERIALS: Between 1977 and 1990, 937 women with Stage I and II breast carcinoma (55% T1N0, 16% T2N0, 18% T1N1, and 11% T2N1) underwent lumpectomy, axillary lymphadenectomy, and definitive irradiation. The median patient age was 52 years. Of the 937 patients, 375 (40%) received adjuvant chemotherapy and/or hormonal therapy, including 249 (92%) of the 270 women with pathologically positive nodes. The median follow-up was 10.1 years. RESULTS: For the overall group, the 15-year overall survival rate was 71%, and the rate of freedom from distant metastases was 76%. The 15-year local failure rate was 19%. The 15-year contralateral breast cancer rate was 12%. The most common first events were distant failure (13%), local failure (10%), contralateral breast cancer (7%), and second malignant neoplasms (6%). The local failure rate at 10 years for favorable subsets of tumors characterized by mammographic detection, resection with negative margins, treatment with chemotherapy, and treatment with hormones was 8%, 10%, 10%, and 7%, respectively. Local failures were most commonly observed within (true recurrence), or just outside (marginal miss), the primary tumor bed (66%, 85 of 128). The rate of true recurrence or marginal miss at 5, 10, and 15 years was 5%, 10%, and 12%, respectively. CONCLUSION: These high rates of survival and local control confirm that breast conservation therapy yields favorable results in women with early breast cancer into the second decade after treatment.


Assuntos
Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/patologia , Terapia Combinada , Feminino , Humanos , Mastectomia Segmentar , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Taxa de Sobrevida
3.
Hematol Oncol Clin North Am ; 16(4): 995-1014, viii, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12418059

RESUMO

The integration of radiotherapy to the adjuvant treatment of rectal cancer was prompted by the predominance of locoregional failures after curative surgery. This characteristic in the pattern of failure is one of the main reasons adjuvant radiotherapy plays a greater role in rectal cancer than in colon cancer. It has been demonstrated that local failure rates after surgery alone for rectal cancer are strongly dependent on the degree of bowel wall invasion, lymph node involvement, and margins of resection. These same locoregional factors are also predictive of distant metastasis and survival. In addition, local failure is associated with devastating symptoms that severely affect the quality of life of patients. For these reasons, locoregional control remains a major issue in the treatment of rectal cancer. This article summarizes the evidence that has established chemoradiotherapy as part of the standard of care for rectal cancer and the techniques used for its delivery.


Assuntos
Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/radioterapia , Terapia Combinada , Humanos , Recidiva Local de Neoplasia , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios , Neoplasias Retais/cirurgia
4.
Cancer ; 103(12): 2447-54, 2005 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15887223

RESUMO

BACKGROUND: The objective of the current study was to determine the long-term results of breast-conservation treatment in women with early-stage, invasive lobular carcinoma of the breast. METHODS: Between 1977 and 1995, 1093 women with Stage I and II invasive ductal carcinoma of the breast and 55 women with invasive lobular carcinoma of the breast underwent lumpectomy, axillary lymph node dissection, and radiation treatment. Overall, 49% of the women received adjuvant systemic therapy (chemotherapy and/or hormones). RESULTS: The median age was 52 years for patients in the invasive ductal group and 54 years for patients in the invasive lobular group. The median follow-up was 8.7 years and 10.2 years for patients in the invasive ductal and invasive lobular groups, respectively. A comparison of patients who had invasive lobular carcinoma with patients who had invasive ductal carcinoma showed no difference in the 10-year actuarial rates of overall survival (85% vs. 79%, respectively; P = 0.73), cause-specific survival (93% vs. 84%, respectively; P = 0.85), or freedom from distant metastases (81% vs. 80%, respectively; P = 0.76). The 10-year rates of local failure were 18% for patients with invasive lobular carcinoma and 12% for patients with invasive ductal carcinoma (P = 0.24), and the 10-year rates of contralateral breast carcinoma development for the 2 groups were 12% and 8%, respectively (P = 0.40). CONCLUSIONS: Breast-conservation treatment yielded similar long-term results for women with early-stage, invasive lobular carcinoma and women with the more prevalent invasive ductal carcinoma.


Assuntos
Neoplasias da Mama/terapia , Carcinoma Ductal de Mama/terapia , Carcinoma Lobular/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/patologia , Quimioterapia Adjuvante , Terapia Combinada , Feminino , Humanos , Excisão de Linfonodo , Mastectomia Segmentar , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Radioterapia Adjuvante , Taxa de Sobrevida , Fatores de Tempo
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