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1.
Int J Radiat Biol ; : 1-9, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38889539

RESUMO

INTRODUCTION: Medulloblastoma is a central nerves tumor that often occurs in pediatrics. The main radiotherapy technique for this tumor type is craniospinal irradiation (CSI), through which the whole brain and spinal cord are exposed to radiation. Due to the immaturity of healthy organs in pediatrics, radiogenic side effects such as second cancer are more severe. Accordingly, the current study aimed to evaluate the risk of secondary cancer development in healthy organs following CSI. MATERIALS AND METHODS: Seven organs at risk (OARs) including skin, eye lens, thyroid, lung, liver, stomach, bladder, colon, and gonads were considered and the dose received by each OAR during CSI was measured inside an anthropomorphic RANDO phantom by TLDs. Then, the mean obtained dose for each organ was used to estimate the probability of secondary malignancy development according to the recommended cancer risk coefficients for specific organs. RESULTS: The results demonstrated that the stomach and colon are at high risk of secondary malignancy occurrence, while the skin has the lowest probability of secondary cancer development. The total received dose after the treatment course by all considered organs was lower than the corresponding tolerable dose levels. CONCLUSIONS: From the results, it can be concluded that some OARs during CSI are highly at risk of secondary cancer development. This issue may be of concern due to organ immaturity in pediatrics which can intensify the radiogenic effects of radiation exposure. Accordingly, strict shielding the OARs during craniospinal radiotherapy and/or sparing them from the radiation field through modern techniques such as hadron therapy is highly recommended.

2.
Med Biol Eng Comput ; 61(2): 435-444, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36460872

RESUMO

A buildup bolus is used during the post-mastectomy radiotherapy (PMRT) to overcome under-dosage issues in the chest wall. The current study is aimed at evaluating the performance of a bolus in dose enhancement through both film dosimetry and treatment planning approaches. Twenty patients were enrolled in current research. The received dose by the skin at the lateral and medial regions of the chest wall in the presence and absence bolus was evaluated. Film dosimetry results showed that the presence of the bolus can averagely increase the skin dose by about 80% (P value < 0.001) and 92% (P value < 0.001) in lateral and medial regions, respectively. No significant difference was observed between the measured and treatment planning system (TPS)-calculated dose values in the presence of bolus. The presence of the bolus can considerably increase the absorbed dose by superficial chest wall regions. The TPS shows a favorable performance in superficial dose calculations in the presence of the buildup bolus. Hosseini et al.: demonstration of implemented research in the current study.


Assuntos
Neoplasias da Mama , Dosimetria Fotográfica , Humanos , Feminino , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Mastectomia , Planejamento da Radioterapia Assistida por Computador , Pele , Dosagem Radioterapêutica
3.
Front Endocrinol (Lausanne) ; 13: 798975, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35299966

RESUMO

Aim: To determine the efficacy and safety of inactivated SARS-CoV-2 vaccine (BBIBP-CorV) in patients with breast cancer. Methods: In this multi- institutional cohort study, a total of 160 breast cancer patients (mean age of 50.01 ± 11.5 years old) were assessed for the SARS-CoV-2 Anti-Spike IgG and SARS-CoV2 Anti RBD IgG by ELISA after two doses of 0.5 mL inactivated, COVID-19 vaccine (BBIBP-CorV). All patients were followed up for three months for clinical COVID-19 infection based on either PCR results or imaging findings. Common Terminology Criteria for Adverse Events were used to assess the side effects. Results: The presence of SARS-CoV-2 anti-spike IgG, SARS-CoV2 anti-RBD IgG, or either of these antibodies was 85.7%, 87.4%, and 93.3%. The prevalence of COVID-19 infection after vaccination was 0.7%, 0% and 0% for the first, second and third months of the follow-up period. The most common local and systemic side-effects were injection site pain and fever which were presented in 22.3% and 24.3% of patients, respectively. Discussion: The inactivated SARS-CoV-2 vaccine (BBIBP-CorV) is a tolerable and effective method to prevent COVID-19.


Assuntos
Neoplasias da Mama , COVID-19 , Adulto , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , RNA Viral , SARS-CoV-2 , Trastuzumab
4.
Cancer Invest ; 40(1): 26-34, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34634986

RESUMO

OBJECTIVE: To evaluate the safety and immunogenicity of the inactivated SARS-CoV-2 vaccine in cancer patients. MATERIAL AND METHOD: 364 cancer patients who received two doses of vaccine were enrolled. The presence of SARS-CoV-2 anti-Spike protein IgG and neutralizing antibody 2 months following vaccination were measured by ELIZA. RESULTS: Injection site pain and fever were the most common local and systemic side effects. The overall seroconversion rate was 86.9% that was lower in older age, those with hematological malignancies and chemotherapy receivers. CONCLUSION: The result of study confirmed the safety and short-term efficacy of inactivated vaccine in patients with malignancies.


Assuntos
Vacinas contra COVID-19/imunologia , Imunogenicidade da Vacina/imunologia , Neoplasias/tratamento farmacológico , Vacinas de Produtos Inativados/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
Cancer Invest ; 40(2): 115-123, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34699294

RESUMO

Patients with cancer are at significantly greater risk of COVID-19 and its complications than the general population. Since IgG antibodies remain detectable well after infection with the SARS-CoV-2 virus, seroprevalence can be used to estimate the proportion of the cancer population previously infected and potentially immune to SARS-CoV-2. The current study is a multi-center, prospective observational study to assess the seroprevalence of SARS-CoV-2 IgG antibody in a cancer population referred for vaccination between April and June 2021. Of a total of 270 adult patients with cancer accrued, 16% reported a history of COVID-19 more than four weeks previously confirmed by PCR. At the same time, serologic positivity for SARSCoV2 IgG was found in 29% of patients prior to vaccination including nearly 20% of patients without a history of confirmed COVID-19. Seropositivity was significantly greater in females consistent with higher rates in patients with breast cancer and gynecologic cancers. A seroconversion rate of 79.5% was observed in cancer patients with a history of PCR confirmed COVID-19, less than observed in the general population. In multivariable analysis, gender and prior history of COVID-19 were both independently associated with seropositivity prior to vaccination. Follow-up is continuing of this cohort of patients with cancer following vaccination to assess antibody and clinical outcomes.


Assuntos
COVID-19/epidemiologia , Imunoglobulina G/sangue , Neoplasias/imunologia , SARS-CoV-2/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , COVID-19/sangue , COVID-19/imunologia , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Estudos Prospectivos , Estudos Soroepidemiológicos , Caracteres Sexuais , Adulto Jovem
6.
Front Oncol ; 11: 779491, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34900732

RESUMO

BACKGROUND: In newly diagnosed glioblastoma, radiation with concurrent and adjuvant (six cycles) temozolomide (TMZ) is the established standard of postsurgical care. However, the benefit of extending adjuvant TMZ therapy beyond six cycles has remained unknown. METHODS: We searched PubMed, Web of Science, Scopus, and Embase up to October 1, 2021. The search keywords were "glioblastoma," "adjuvant chemotherapy," and their synonyms. The data of randomized clinical trials were extracted and included in this meta-analysis if they had reported patients' median overall survival (OS) or median progression-free survival (PFS). The standard and extended chemotherapy regimens were considered as adjuvant TMZ up to six cycles and beyond six cycles (up to a total of 12 cycles), respectively. The median OS and median PFS were pooled and compared. RESULTS: Four studies consisting of 882 patients (461 patients for the standard chemotherapy group and 421 patients for the extended chemotherapy group) were included in this meta-analysis. The extended TMZ regimen was associated with a nonsignificant improvement in PFS [12.0 months (95% CI 9.0 to 15.0) vs. 10.0 months (95% CI 7.0 to 12.0), P = 0.27] without corresponding improvement in OS [23.0 months (95% CI 19.0 to 27.0) and 24.0 months (95% CI 20.0 to 28.0), P = 0.73]. CONCLUSIONS: In newly diagnosed glioblastoma, continuing adjuvant TMZ beyond six cycles did not shown an increase neither in PFS nor OS.

7.
Clin Case Rep ; 9(10): e04904, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34631087

RESUMO

In children and adolescents presenting with skull base sarcoma, treatment strategies will face challenging decisions due to the unique chemoresistant pathologies, limitations imposed by the not-yet fully mature anatomical structures, and the small surgical site.

8.
Radiol Phys Technol ; 14(3): 226-237, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34043155

RESUMO

This study aimed to evaluate variations in dose distribution within the target volume and dose received by the organs at risk (OARs) for different tangential field arrangements during three-dimensional (3D) conformal treatment planning for left-sided breast cancer. Computed tomography (CT) images of 25 breast cancer patients were included, and three different mono-isocentric half-block (MIHB) treatment plans-parallel central axis technique (PCAXT), posterior border parallel technique (PBPT), and parallel quadrant technique (PQUDT)-were considered for each patient. The dosimetric and geometric parameters related to each followed plan were then extracted for the planning target volume (PTV) and the OARs, and compared. The results showed no significant differences among the extracted dosimetric and geometric parameters of the OARs for the different plans, while the Dmax, V95%, homogeneity index (HI), and conformity index (CI) values related to the PTV were significantly different (P < 0.05). The lowest Dmax and V95% values inside the PTV were related to the PCAXT plan. The best HI was achieved with the PBPT plan, whereas the best CI was observed for the PCAXT plan. The best correlation between the geometric and dosimetric parameters of the OARs was between V5Gy-central lung distance for the ipsilateral lung and the V5Gy-maximum heart distance for the heart in all plans. These results demonstrate that variations in the tangential field arrangement at the posterior border for optimal coverage of the PTV may not considerably affect the dose received by the OARs.


Assuntos
Neoplasias da Mama , Radioterapia de Intensidade Modulada , Neoplasias Unilaterais da Mama , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/radioterapia , Feminino , Humanos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Neoplasias Unilaterais da Mama/diagnóstico por imagem , Neoplasias Unilaterais da Mama/radioterapia
9.
Dose Response ; 18(3): 1559325820962600, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33088245

RESUMO

BACKGROUND AND PURPOSE: To assess the feasibility of a treatment planning system in localizing, contouring, and targeting lung lesions along with an evaluation of volume indices of lung involvement in patients with COVID-19 pneumonia. METHODS: We evaluated 10 patients with PCR-confirmed COVID-19 pneumonia. The CT images were imported into the ISOgray® treatment planning system to anatomically define and contour the volumes of the pulmonary lesions, the lungs, and other nearby organs. RESULTS: The ratio of lung lesion volume to lung volume in this study was 0.11 ± 0.13 (11.13%). The highest mean biosynthesis ratio of lung lesions was 0.36. The ratio of lesion volume in the left lung of patients with the highest volume of involvement, was 0.44, and the ratio of lesion volume in the right lung of these patients was 0.27 (approximately 1.5 times more in the left lung than the right lung). On average, CTDIvol and DLP for all patients studied in our study were 11.22 ± 2.47 mGy and 354.20 ± 65.11 mGy.cm. CONCLUSION: We reported the feasibility of using a treatment planning system in localizing COVID-19 pulmonary lesions and its validity in the volumetric assessment of infected lung regions.

10.
J Family Med Prim Care ; 8(10): 3263-3267, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31742153

RESUMO

BACKGROUND AND OBJECTIVES: Effective relationship and collaboration between doctors and nurses is considered the main factor in achieving positive medical results, which is the most important goal of the healthcare system. This study aims to compare attitude of doctors and nurses toward factors associated with doctor-nurse collaboration, including shared education and teamwork, caring as opposed to curing, physician's dominance, and nurses' autonomy. METHODS: In this cross sectional, descriptive-comparative study, the Jefferson Scale of Attitudes toward Physician-Nurse Collaboration was used to assess doctor-nurse collaboration in four domains, including shared education and teamwork, caring as opposed to curing, physician's dominance, and nurses' autonomy. To this end, descriptive (mean, standard deviation) and inferential statistics including independent t test, Chi-square, and variance analysis were used. RESULTS: According to the results obtained, compared to doctors, nurses showed a more positive attitude toward shared education and teamwork, caring as opposed to curing, and physicians' dominance, but there was no significant difference between the two groups in nurses' autonomy. CONCLUSION: With regard to doctor-nurse collaboration, it is essential that doctors and nurses be acculturated in the course of their academic education. Moreover, policies to change pattern of professional relationships from hierarchical to complementary can be effective in enhancing professional autonomy of nurses and reducing impaired professional interactions.

11.
J Family Med Prim Care ; 8(7): 2173-2178, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31463226

RESUMO

The occurrence of chronic proctitis as a side effect among radiotherapy patients is about 5%. Radiation proctitis and consequent development of chronic proctitis are not associated to each other. However, a lot of samples of proctitis that are limited easily could be treated by typical remedial techniques. Improvements in radiotherapy techniques that make possible the delivery of superior doses of radiation could easily reduce both chronic and acute proctitis. The step-by-step remedial procedure for treatment of this disorder starts with conservative remedial management and includes iron substitution as a second-line therapy. For patients who did not receive initial therapies, sucralfate injection, topical corticosteroids, and antidiarrhea therapy were provided as a means of aggressive care. In cases of continuous rectal bleeding, remedial laser techniques and formaldehyde administration should be attempted before surgical therapy. When surgical therapy is required, a descending or transverse colostomy must be carried out. Advanced methods such as intraperitoneal injections of formalin or novel methods of cold therapy and radiofrequency ablation (RFA) provide a wider remedial field. Exceptionally, unanticipated conclusion of neosquamous wound healing via RFA may have additional preponderances in stopping symptoms and may require better assessment through accurate randomized examination. Since aggressive treatments like coloanal anastomosis and colorectal surgery are correlated with remarkable mortality and morbidity, they must be considered as the final course of remedial treatment.

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