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1.
The goal of radiotherapy is to eradicate a tumor without causing severe damage to healthy tissues. Various published experiences have lead to the conclusion that an overall precision of +/- 5% on the absorbed doses, at any point in the patient, is required to meet this goal. Clear definitions of the method for specifying the absorbed dose and dose homogeneity throughout the target volume are essential, to facilitate communication, to improve the knowledge of dose-effect relations and to establish the necessary criteria for the optimization of treatment plans. Determination of the optimal energy is one of the most controversial problems in treatment plan optimization. It is clearly related to the criteria selected. A brief review of some criteria is proposed according to the tumor site. Computers may provide three-dimensional dose calculations for treatment conditions for which manual calculations are not feasible. Because the random errors are very small, computer calculations are often considered as exact although large risks of error are associated with each step of the calculation. The reduction of the overall uncertainty to the stated level of +/- 5% requires a constant effort from both radiotherapists and physicists at each step of treatment planning from basic definitions to dose distribution calculations.  相似文献   

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Twenty-nine patients with multiple myeloma, 16 untreated and 13 relapsing after treatment with melphalan and/or cyclophosphamide, were treated with Peptichemio (PTC), vincristine (VCR) and prednisone (PRD). The treatment was well tolerated and produced rapid resolution of bone pain and improved performance status in symptomatic patients. Rapid and marked monoclonal component reduction (greater than 50 per cent) was noted in 50% of previously untreated and 31% of previously treated patients. The median survival of previously untreated patients was 27 months, 19 months for stage III patients. Four patients resistant to common alkylating agents responded to PTC-VCR-PRD treatment and achieved long remissions (from 18 to 38 months). The therapeutic results suggest that the present combination regimen may be indicated for induction treatment of multiple myeloma patients in an advanced stage of the disease, and for treatment of myeloma patients refractory or resistant to melphalan and/or cyclophosphamide.  相似文献   

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Pheochromocytomas are rare, catecholamine-secreting tumors arising most frequently in the chromaffin cells of the adrenal glands. Recent studies have suggested that genetic mutations are more frequent than previously appreciated in patients with these lesions. Advances continue to be made not only in the genetic evaluation of these patients but also in the biochemical confirmation and tumor localization. Surgery remains the definitive treatment, and advances in laparoscopic techniques as well as cortical-sparing procedures have reduced the morbidity associated with tumor resection.  相似文献   

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This study examines differences between cancer centers (CC) and noncancer centers (NCC) in terms of management procedures and outcomes for three pediatric solid tumors: Wilms' tumor (N = 147), rhabdomyosarcoma (N = 87), and medulloblastoma (N = 76). Data were derived for the period 1970-1979 from the population-based Greater Delaware Valley Pediatric Tumor Registry maintained at the Children's Cancer Research Center, which routinely collects data on all childhood neoplasms that occur in a 31-county region. Management measures reviewed included the degree to which important pretreatment evaluations were performed, types of therapy used, and extent of follow-up examinations conducted. Outcome variables were three-year disease-free survival and frequency of deaths related to complications of therapy. Differences in three-year disease-free survival between CC and NCC were noted for medulloblastoma (52% v 24%) and rhabdomyosarcoma (48% v 10%), but not for Wilms' tumor (79% v 68%). Among medulloblastoma patients, differences were detected in the frequency of pretreatment evaluations and in the therapy used. The principal management contrast found in rhabdomyosarcoma was that multiagent chemotherapy was used less often in NCC. Wilms' tumor patients were evaluated and treated similarly in the community versus the CC, except for some contrasts in the surgical approach and the frequency of follow-up for the detection of late complications.  相似文献   

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PURPOSE: To report current technology implementation, radiation therapy physics and treatment planning practices, and results of treatment planning exercises among 261 institutions belonging to the Children's Oncology Group (COG). METHODS AND MATERIALS: The Radiation Therapy Committee of the newly formed COG mandated that each institution demonstrate basic physics and treatment planning abilities by satisfactorily completing a questionnaire and four treatment planning exercises designed by the Quality Assurance Review Center. The planning cases are (1) a maxillary sinus target volume (for two-dimensional planning), (2) a Hodgkin's disease mantle field (for irregular-field and off-axis dose calculations), (3) a central axis blocked case, and (4) a craniospinal irradiation case. The questionnaire and treatment plans were submitted (as of 1/30/02) by 243 institutions and completed satisfactorily by 233. Data from this questionnaire and analyses of the treatment plans with monitor unit calculations are presented. RESULTS: Of the 243 clinics responding, 54% use multileaf collimators routinely, 94% use asymmetric jaws routinely, and 13% use dynamic wedges. Nearly all institutions calibrate their linear accelerators following American Association of Physicists in Medicine protocols, currently 16% with TG-51 and 81% with TG-21 protocol. Treatment planning systems are relied on very heavily for all calculations, including monitor units. Techniques and results of each of the treatment planning exercises are presented. CONCLUSIONS: Together, these data provide a unique compilation of current (2001) radiation therapy practices in institutions treating pediatric patients. Overall, the COG facilities have the equipment and the personnel to perform high-quality radiation therapy. With ongoing quality assurance review, radiation therapy compliance with COG protocols should be high.  相似文献   

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Scully C  Bagan JV 《Oral oncology》2008,44(3):211-215
This paper provides a synopsis of the main papers on imaging, treatment and treatment outcomes in patients with oral and oropharyngeal squamous cell carcinoma (OSCC) and head and neck SCC (HNSCC) published in 2007 in Oral Oncology - an international interdisciplinary journal which publishes high quality original research, clinical trials and review articles, and all other scientific articles relating to the aetiopathogenesis, epidemiology, prevention, clinical features, diagnosis, treatment and management of patients with neoplasms in the head and neck, and orofacial disease in patients with malignant disease.  相似文献   

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Answer questions and earn CME/CNE A measles outbreak originating in California during 2014 and 2015 called attention to the potential for infectious disease outbreaks related to underimmunized populations in the United States and the potential risk to pediatric patients with cancer attending school when such outbreaks occur. Compliance with vaccine recommendations is important for the prevention of hepatitis B‐related and human papillomavirus‐related cancers and for protecting immunocompromised patients with cancer, and these points are often overlooked, resulting in the continued occurrence of vaccine‐preventable neoplastic and infectious diseases and complications. This article provides an overview of the importance of vaccines in the context of cancer and encourages clinician, health system, and public policy efforts to promote adherence to immunization recommendations in the United States. CA Cancer J Clin 2017;67:398–410. © 2017 American Cancer Society.  相似文献   

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Answer questions and earn CME/CNE Hot flashes are prevalent and severe symptoms that can interfere with mood, sleep, and quality of life for women and men with cancer. The purpose of this article is to review existing literature on the risk factors, pathophysiology, and treatment of hot flashes in individuals with cancer. Electronic searches were conducted to identify relevant English‐language literature published through June 15, 2012. Results indicated that risk factors for hot flashes in cancer include patient‐related factors (eg, age, race/ethnicity, educational level, smoking history, cardiovascular risk including body mass index, and genetics) and disease‐related factors (eg, cancer diagnosis and dose/type of treatment). In addition, although the pathophysiology of hot flashes has remained elusive, these symptoms are likely attributable to disruptions in thermoregulation and neurochemicals. Therapies that have been offered or tested fall into 4 broad categories: pharmacological, nutraceutical, surgical, and complementary/behavioral strategies. The evidence base for this broad range of therapies varies, with some treatments not yet having been fully tested or showing equivocal results. The evidence base surrounding all therapies is evaluated to enhance hot flash treatment decision‐making by clinicians and patients. CA Cancer J Clin 2013. © 2013 American Cancer Society.  相似文献   

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Answer questions and earn CME/CNE People with mental illness die decades earlier in the United States compared with the general population. Most of this disparity is related to preventable and treatable chronic conditions, with many studies finding cancer as the second leading cause of death. Individual lifestyle factors, such as smoking or limited adherence to treatment, are often cited as highly significant issues in shaping risk among persons with mental illness. However, many contextual or systems‐level factors exacerbate these individual factors and may fundamentally drive health disparities among people with mental illness. The authors conducted an integrative review to summarize the empirical literature on cancer prevention, screening, and treatment for people with mental illness. Although multiple interventions are being developed and tested to address tobacco dependence and obesity in these populations, the evidence for effectiveness is quite limited, and essentially all prevention interventions focus at the individual level. This review identified only one published article describing evidence‐based interventions to promote cancer screening and improve cancer treatment in people with mental illness. On the basis of a literature review and the experience and expertise of the authors, each section in this article concludes with suggestions at the individual, interpersonal, organizational, community, and policy levels that may improve cancer prevention, screening, and treatment in people with mental illness. CA Cancer J Clin 2016;66:133–151. © 2015 American Cancer Society.  相似文献   

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Interleukin-8 (CXCL8) was originally described as a chemokine whose main function is the attraction of a polymorphonuclear inflammatory leukocyte infiltrate acting on CXCR1/2. Recently, it has been found that tumors very frequently coopt the production of this chemokine, which in this malignant context exerts different pro-tumoral functions. Reportedly, these include angiogenesis, survival signaling for cancer stem cells and attraction of myeloid cells endowed with the ability to immunosuppress and locally provide growth factors. Given the fact that in cancer patients IL-8 is mainly produced by tumor cells themselves, its serum concentration has been shown to correlate with tumor burden. Thus, IL-8 serum concentrations have been shown to be useful as a pharmacodynamic biomarker to early detect response to immunotherapy. Finally, because of the roles that IL-8 plays in favoring tumor progression, several therapeutic strategies are being developed to interfere with its functions. Such interventions hold promise, especially for therapeutic combinations in the field of cancer immunotherapy.  相似文献   

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Aims

Patients with locally advanced gastrointestinal stromal tumours (GISTs) have a high risk of tumour perforation, incomplete tumour resections and often require multivisceral resections. Long-term disease-free and overall survival is usually impaired in this group of patients. Induction therapy with imatinib followed by surgery seems to be beneficial in terms of improved surgical results and long-term outcome. We report on a large cohort of locally advanced GIST patients who have been treated in four centres in the Netherlands specialized in the treatment of sarcomas.

Methods

Between August 2001 and June 2011, 57 patients underwent surgery for locally advanced GISTs after imatinib treatment. Data of all patients were retrospectively collected. Endpoints were progression-free and overall survival.

Results

The patients underwent surgery after a median of 8 (range 1–55) months of imatinib treatment. Median tumour size before treatment was 12.2 (range 5.2–30) cm and reduced to 6.2 (range 1–20) cm before surgery. No tumour perforation occurred and a surgical complete (R0) resection was achieved in 48 (84%) patients. Five-year PFS and OS were 77% and 88%. Eight patients had recurrent/metastatic disease.

Conclusions

Imatinib in locally advanced GIST is feasible and enables a high complete resection rate without tumour rupture. The combination of imatinib and surgery in patients with locally advanced GIST seems to improve PFS and OS.  相似文献   

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