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1.
Cancer Radiother ; 28(3): 258-264, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38866652

RESUMO

PURPOSE: Commercial vendors have created artificial intelligence (AI) tools for use in all aspects of life and medicine, including radiation oncology. AI innovations will likely disrupt workflows in the field of radiation oncology. However, limited data exist on using AI-based chatbots about the quality of radiation oncology information. This study aims to assess the accuracy of ChatGPT, an AI-based chatbot, in answering patients' questions during their first visit to the radiation oncology outpatient department and test knowledge of ChatGPT in radiation oncology. MATERIAL AND METHODS: Expert opinion was formulated using a set of ten standard questions of patients encountered in outpatient department practice. A blinded expert opinion was taken for the ten questions on common queries of patients in outpatient department visits, and the same questions were evaluated on ChatGPT version 3.5 (ChatGPT 3.5). The answers by expert and ChatGPT were independently evaluated for accuracy by three scientific reviewers. Additionally, a comparison was made for the extent of similarity of answers between ChatGPT and experts by a response scoring for each answer. Word count and Flesch-Kincaid readability score and grade were done for the responses obtained from expert and ChatGPT. A comparison of the answers of ChatGPT and expert was done with a Likert scale. As a second component of the study, we tested the technical knowledge of ChatGPT. Ten multiple choice questions were framed with increasing order of difficulty - basic, intermediate and advanced, and the responses were evaluated on ChatGPT. Statistical testing was done using SPSS version 27. RESULTS: After expert review, the accuracy of expert opinion was 100%, and ChatGPT's was 80% (8/10) for regular questions encountered in outpatient department visits. A noticeable difference was observed in word count and readability of answers from expert opinion or ChatGPT. Of the ten multiple-choice questions for assessment of radiation oncology database, ChatGPT had an accuracy rate of 90% (9 out of 10). One answer to a basic-level question was incorrect, whereas all answers to intermediate and difficult-level questions were correct. CONCLUSION: ChatGPT provides reasonably accurate information about routine questions encountered in the first outpatient department visit of the patient and also demonstrated a sound knowledge of the subject. The result of our study can inform the future development of educational tools in radiation oncology and may have implications in other medical fields. This is the first study that provides essential insight into the potentially positive capabilities of two components of ChatGPT: firstly, ChatGPT's response to common queries of patients at OPD visits, and secondly, the assessment of the radiation oncology knowledge base of ChatGPT.


Assuntos
Inteligência Artificial , Radioterapia (Especialidade) , Humanos , Bases de Dados Factuais , Prova Pericial , Inquéritos e Questionários , Neoplasias/radioterapia
2.
3 Biotech ; 13(6): 207, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37229276

RESUMO

Yellow mosaic disease, a most important destructive disease of mungbean production caused by Mungbean yellow mosaic India virus (MYMIV) under North Indian conditions. However, management of this deadly disease is still becoming the biggest challenge due to breaking of resistance under changing climatic conditions. Hence, a field experiment was conducted at IARI, New Delhi, India during Kharif 2021 and Spring-Summer 2022 to understand the sowing date influence on incidence of MYMIV in mungbean resistant (Pusa 1371) and susceptible (Pusa 9531) cultivars. The results revealed the higher disease incidence percentage (PDI) in the first sowing (15-20th July) of Kharif and third sowing (5-10th April) of Spring-Summer season. The mean PDI ranged from 25-41% to 11.80-13.54% for resistant followed by 23.13-49.84% and 14.40-21.45% in susceptible cultivar during Kharif and Spring-Summer season respectively. The detection of MYMIV through DAC-ELISA at 405 nm showed the absorbance values of 0.40-0.60 in susceptible and < 0.45 in resistant cultivar during the Kharif and 0.40-0.45 in Spring-Summer season. The PCR analysis with MYMIV and MYMV specific primers indicated the presence of only MYMIV and absence of MYMV in the present studied mungbean cultivars. The PCR analysis with DNA-B specific primers resulted in the amplification of 850 bp from both susceptible and resistant cultivars during the first sowing of Kharif whereas amplification was observed only in susceptible cultivar with second and third sowings of Kharif and all the three sowings of Spring-Summer season. The experiment results revealed that the most suitable date of sowing for mungbean will be before 30th March during Spring-Summer and after third week of July (30th July to 10th August) during the Kharif season under Delhi conditions. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03621-z.

3.
Front Genet ; 13: 957360, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36092914

RESUMO

Cucumber is a model plant for studying parthenocarpy with abundant slicing- and pickling-type germplasm. This study was undertaken to understand the role of the important cytokines (CKs), auxin (AUX) and gibberellin (GA) biosynthesis and degradation genes for the induction of parthenocarpy in slicing and pickling germplasm. Two genotypes of gynoecious parthenocarpic cucumber, PPC-6 and DG-8, along with an MABC-derived gynoecious non-parthenocarpic line, IMPU-1, were evaluated in this study. The slicing and pickling cucumber genotypes PPC-6 and DG-8 were strongly parthenocarpic in nature and set fruit normally without pollination. Endogenous auxin and gibberellin were significantly higher in parthenocarpic than non-parthenocarpic genotypes, whereas the concentration of cytokinins varied among the genotypes at different developmental stages. However, the exogenous application of Zeatin and IAA + Zeatin was effective in inducing parthenocarpic fruit in IMPU-1. Expression analysis with important CK, AUX, and GA biosynthesis-related genes was conducted in IMPU-1, PPC-6, and DG-8. The expression of the CK synthase, IPT, IPT3, PaO, LOG1, LOG2, CYP735A1, and CYP735A2 was up-regulated in the parthenocarpic genotypes. Among the transcription factor response regulators (RRs), positive regulation of CSRR8/9b, CSRR8/9d, CSRR8/9e, and CSRR16/17 and negative feedback of the CK signalling genes, such as CsRR3/4a, CsRR3/4b, CsRR8/9a, and CsRR8/9c, were recorded in the parthenocarpic lines. Homeostasis between cytokinin biosynthesis and degradation genes such as CK oxidases (CKXs) and CK dehydrogenase resulted in a non-significant difference in the endogenous CK concentration in the parthenocarpic and non-parthenocarpic genotypes. In addition, up-regulation of the key auxin-inducing proteins and GA biosynthesis genes indicated their crucial role in the parthenocarpic fruit set of cucumber. This study establishes the critical role of the CKs, AUX, and GA regulatory networks and their cross-talk in determining parthenocarpy in slicing and pickling cucumber genotypes.

4.
Front Plant Sci ; 13: 884476, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35991462

RESUMO

Cucumber is an extremely perishable vegetable; however, under room conditions, the fruits become unfit for consumption 2-3 days after harvesting. One natural variant, DC-48 with an extended shelf-life was identified, fruits of which can be stored up to 10-15 days under room temperature. The genes involved in this economically important trait are regulated by non-coding RNAs. The study aims to identify the long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) by taking two contrasting genotypes, DC-48 and DC-83, at two different fruit developmental stages. The upper epidermis of the fruits was collected at 5 days and 10 days after pollination (DAP) for high throughput RNA sequencing. The differential expression analysis was performed to identify differentially expressed (DE) lncRNAs and circRNAs along with the network analysis of lncRNA, miRNA, circRNA, and mRNA interactions. A total of 97 DElncRNAs were identified where 18 were common under both the developmental stages (8 down regulated and 10 upregulated). Based on the back-spliced reads, 238 circRNAs were found to be distributed uniformly throughout the cucumber genomes with the highest numbers (71) in chromosome 4. The majority of the circRNAs (49%) were exonic in origin followed by inter-genic (47%) and intronic (4%) origin. The genes related to fruit firmness, namely, polygalacturonase, expansin, pectate lyase, and xyloglucan glycosyltransferase were present in the target sites and co-localized networks indicating the role of the lncRNA and circRNAs in their regulation. Genes related to fruit ripening, namely, trehalose-6-phosphate synthase, squamosa promoter binding protein, WRKY domain transcription factors, MADS box proteins, abscisic stress ripening inhibitors, and different classes of heat shock proteins (HSPs) were also found to be regulated by the identified lncRNA and circRNAs. Besides, ethylene biosynthesis and chlorophyll metabolisms were also found to be regulated by DElncRNAs and circRNAs. A total of 17 transcripts were also successfully validated through RT PCR data. These results would help the breeders to identify the complex molecular network and regulatory role of the lncRNAs and circRNAs in determining the shelf-life of cucumbers.

5.
Clin. transl. oncol. (Print) ; 24(6): 997-1013, junio 2022.
Artigo em Inglês | IBECS | ID: ibc-203802

RESUMO

Non-proteincoding transcripts bearing 200 base pairs known as long non-coding RNAs (lncRNAs) play a role in a variety of molecular mechanisms, including cell differentiation, apoptosis and metastasis. Previous studies have suggested that frequently dysregulated lncRNAs play a crucial role in various aspects of cancer metastasis. Metastasis is the main leading cause of death in cancer. The role of lncRNAs in different stages of metastasis is the subject of this review. Based on in vitro and in vivo investigations on metastasis, we categorized lncRNAs into distinct stages of metastasis including angiogenesis, invasion, intravasation, survival in circulation, and extravasation. The involvement of lncRNAs in angiogenesis and invasion has been extensively studied. Here, we comprehensively discuss the role and functions of these lncRNAs with a particular focus on the molecular mechanisms.


Assuntos
Humanos , Apoptose , Neoplasias/genética , Neovascularização Patológica , RNA , Metástase Neoplásica , RNA Longo não Codificante , Transdução de Sinais
6.
Clin Oncol (R Coll Radiol) ; 34(10): e437-e445, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35469742

RESUMO

AIM: To evaluate the temporal growth pattern of female radiation/clinical oncologists (FRCOs) and, if applicable, predict the gender neutrality in different countries of South Asia. MATERIALS AND METHODS: South Asia is composed of Afghanistan, Bhutan, Maldives, Bangladesh, India, Nepal, Pakistan and Sri Lanka. The growth pattern of FRCOs in the latter five countries having radiation oncology facilities was evaluated from respective national registration data. Based on the average annual differential growth rate, together with the already existing female and male radiation/clinical oncologists (MRCOs), the cumulative numbers of FRCOs and MRCOs were forecasted for the next 10 years. The data regarding FRCOs in a leadership position were also calculated from different sources. RESULTS: The total number of radiation/clinical oncologists in the region was 4074, of which 91.8% were in India, because of its vast population. The overall number of FRCOs and MRCOs stood at 1370 and 2704, with a 1:2 female:male ratio. The average incremental annual growth of FRCOs in India was the highest (12.7 persons/year) and Nepal was the lowest (0.4 persons/year), with no data from Pakistan. If the current growth rate is sustained, Indian gender neutrality will be achieved by 2027-2030. In other countries, gender neutrality is unlikely to be achieved in the near future. With regards to leadership positions, 56-77 radiation oncology departments in India, one each in Bangladesh and Sri Lanka are headed by FRCOs, whereas Nepal and Pakistan have none. CONCLUSIONS: With the current growth rate of FRCOs and MRCOs, India will achieve gender parity within a decade; however, the rest of the countries will not achieve this in the near future. Analysis of radiation/clinical oncologists' registration data with their respective national bodies revealed an encouraging growth in the number of FRCOs as against their male counterparts in the last 5 years, compared with previous decades, especially in Bangladesh, Sri Lanka and India. Sri Lanka show high gender neutrality and adopted a multi-tasking and holistic approach of clinical oncology practices as also seen in Scandinavian countries. Such practice may be helpful to improve gender equality in radiation/clinical oncology practice for the other countries in the South Asian region.


Assuntos
Liderança , Oncologistas , Bangladesh , Feminino , Humanos , Índia , Masculino , Sri Lanka
7.
Clin Transl Oncol ; 24(6): 997-1013, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35119654

RESUMO

Non-proteincoding transcripts bearing 200 base pairs known as long non-coding RNAs (lncRNAs) play a role in a variety of molecular mechanisms, including cell differentiation, apoptosis and metastasis. Previous studies have suggested that frequently dysregulated lncRNAs play a crucial role in various aspects of cancer metastasis. Metastasis is the main leading cause of death in cancer. The role of lncRNAs in different stages of metastasis is the subject of this review. Based on in vitro and in vivo investigations on metastasis, we categorized lncRNAs into distinct stages of metastasis including angiogenesis, invasion, intravasation, survival in circulation, and extravasation. The involvement of lncRNAs in angiogenesis and invasion has been extensively studied. Here, we comprehensively discuss the role and functions of these lncRNAs with a particular focus on the molecular mechanisms.


Assuntos
Neoplasias , RNA Longo não Codificante , Apoptose , Humanos , Neoplasias/genética , Neovascularização Patológica , RNA Longo não Codificante/genética
8.
Genomics ; 114(2): 110273, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35092817

RESUMO

Cucumber fruits are perishable in nature and become unfit for market within 2-3 days of harvesting. A natural variant, DC-48 with exceptionally high shelf life was developed and used to dissect the genetic architecture and molecular mechanism for extended shelf life through RNA-seq for first time. A total of 1364 DEGs were identified and cell wall degradation, chlorophyll and ethylene metabolism related genes played key role. Polygalacturunase (PG), Expansin (EXP) and xyloglucan were down regulated determining fruit firmness and retention of fresh green colour was mainly attributed to the low expression level of the chlorophyll catalytic enzymes (CCEs). Gene regulatory networks revealed the hub genes and cross-talk associated with wide variety of the biological processes. Large number of SSRs (21524), SNPs (545173) and InDels (126252) identified will be instrumental in cucumber improvement. A web genomic resource, CsExSLDb developed will provide a platform for future investigation on cucumber post-harvest biology.


Assuntos
Cucumis sativus , Biologia , Clorofila/metabolismo , Cucumis sativus/genética , Frutas/genética , Frutas/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genótipo
10.
Clin. transl. oncol. (Print) ; 23(8): 1497-1510, ago. 2021.
Artigo em Inglês | IBECS | ID: ibc-222148

RESUMO

Discoidin domain receptors, DDR1 and DDR2 are members of the receptor tyrosine kinase (RTK) family that serves as a non-integrin collagen receptor and were initially identified as critical regulators of embryonic development and cellular homeostasis. In recent years, numerous studies have focused on the role of these receptors in disease development, in particular, cancer where they have been reported to augment ECM remodeling, invasion, drug resistance to facilitate tumor progression and metastasis. Interestingly, accumulating evidence also suggests that DDRs promote apoptosis and suppress tumor progression in various human cancers due to which their functions in cancer remain ill-defined and presents a case of an interesting therapeutic target. The present review has discussed the role of DDRs in tumorigenesis and the metastasis (AU)


Assuntos
Humanos , Receptor com Domínio Discoidina 1/fisiologia , Receptor com Domínio Discoidina 2/fisiologia , Neoplasias/etiologia , Neoplasias/metabolismo , Receptor com Domínio Discoidina 1/genética , Receptor com Domínio Discoidina 2/genética , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos , Matriz Extracelular , Invasividade Neoplásica , Metástase Neoplásica , Colágeno/metabolismo , Apoptose
12.
Sci Rep ; 11(1): 4109, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33603131

RESUMO

Bitter gourd (Momordica charantia L.) is an economically important vegetable crop grown in tropical parts of the world. In this study, a high-density linkage map of M. charantia was constructed through genotyping-by-sequencing (GBS) technology using F2:3 mapping population generated from the cross DBGy-201 × Pusa Do Mausami. About 2013 high-quality SNPs were assigned on a total of 20 linkage groups (LGs) spanning over 2329.2 CM with an average genetic distance of 1.16 CM. QTL analysis was performed for six major yield-contributing traits such as fruit length, fruit diameter, fruit weight, fruit flesh thickness, number of fruits per plant and yield per plant. These six quantitative traits were mapped with 19 QTLs (9 QTLs with LOD > 3) using composite interval mapping (CIM). Among 19 QTLs, 12 QTLs derived from 'Pusa Do Mausami' revealed a negative additive effect when its allele increased trait score whereas 7 QTLs derived from 'DBGy-201' revealed a positive additive effect when its allele trait score increased. The phenotypic variation (R2%) elucidated by these QTLs ranged from 0.09% (fruit flesh thickness) on LG 14 to 32.65% (fruit diameter) on LG 16 and a total of six major QTLs detected. Most QTLs detected in the present study were located relatively very close, maybe due to the high correlation among the traits. This information will serve as a significant basis for marker-assisted selection and molecular breeding in bitter gourd crop improvement.


Assuntos
Frutas/genética , Momordica charantia/genética , Locos de Características Quantitativas/genética , Alelos , Mapeamento Cromossômico/métodos , Ligação Genética/genética , Testes Genéticos/métodos , Fenótipo , Polimorfismo de Nucleotídeo Único/genética
13.
Clin Transl Oncol ; 23(8): 1497-1510, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33634432

RESUMO

Discoidin domain receptors, DDR1 and DDR2 are members of the receptor tyrosine kinase (RTK) family that serves as a non-integrin collagen receptor and were initially identified as critical regulators of embryonic development and cellular homeostasis. In recent years, numerous studies have focused on the role of these receptors in disease development, in particular, cancer where they have been reported to augment ECM remodeling, invasion, drug resistance to facilitate tumor progression and metastasis. Interestingly, accumulating evidence also suggests that DDRs promote apoptosis and suppress tumor progression in various human cancers due to which their functions in cancer remain ill-defined and presents a case of an interesting therapeutic target. The present review has discussed the role of DDRs in tumorigenesis and the metastasis.


Assuntos
Receptor com Domínio Discoidina 1/fisiologia , Receptor com Domínio Discoidina 2/fisiologia , Neoplasias/etiologia , Apoptose , Colágeno/metabolismo , Receptor com Domínio Discoidina 1/química , Receptor com Domínio Discoidina 1/genética , Receptor com Domínio Discoidina 2/química , Receptor com Domínio Discoidina 2/genética , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos , Matriz Extracelular , Humanos , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias/metabolismo , Mutação Puntual , Transdução de Sinais
14.
Cancer Radiother ; 25(4): 373-379, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33589330

RESUMO

Stereotactic body radiotherapy (SBRT) is a high precision technique that is commonly used for malignant lesions in lung, liver, pancreas and spine. Recent reports suggest promise in use of SBRT as a tool in atrial and ventricular cardiac arrhythmias. The present systematic review deals with the use of SBRT technology for this novel indication. A PubMed search was done for articles published between 1990 and 2020. All original articles, case reports, case series of treated patients were included in the analyses. Out of the 55 articles in PubMed search, our search found 1 phase I/II clinical case series, 3 clinical case reports, 3 animal studies and 4 dosimetric studies related to cardiac SBRT for arrythmias. All studies used a uniform cardiac dose of 25Gy. The available preclinical, dosimetric and clinical studies have suggested that SBRT for cardiac arrhythmias could become a potential alternative in suitable patients. Cardiac and radiation oncology community await further data and experience in this modality, including safety and outcomes.


Assuntos
Arritmias Cardíacas/radioterapia , Radiocirurgia/métodos , Animais , Fibrilação Atrial/radioterapia , Cães , Humanos , Dosagem Radioterapêutica , Suínos , Taquicardia Ventricular/radioterapia
15.
ACS Appl Mater Interfaces ; 11(14): 13514-13522, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30892012

RESUMO

We developed a new technique to fabricate single nanowire devices with reliable graphene/nanowire contacts using a position-controlled microtransfer and an embedded nanowire structure in a planar junction configuration. A thorough study of electrical properties and fabrication challenges of single p-GaAs nanowire/graphene devices was carried out in two different device configurations: (1) a graphene bottom-contact device where the nanowire-graphene contact junction is formed by transferring a nanowire on top of graphene and (2) a graphene top-contact device where the nanowire-graphene contact junction is formed by transferring graphene on top of an embedded nanowire. For the graphene top-contact devices, graphene-nanowire-metal devices, where graphene is used as one electrode and metal is the other electrode to a nanowire, and graphene-nanowire-graphene devices, where both electrodes to a nanowire are graphene, were investigated and compared with conventional metal/p-GaAs nanowire devices. Conventional metal/p-GaAs nanowire contact devices were further investigated in embedded and nonembedded nanowire device configurations. A significantly improved current in the embedded device configuration is explained with a "parallel resistors model" where the high-resistance parts with the metal-semiconductor Schottky contact and the low-resistance parts with noncontacted facets of the hexagonal nanowires are taken into consideration. Consistently, the nonembedded nanowire structure is found to be depleted much easier than the embedded nanowires from which an estimation for a fully depleted condition has also been established.

16.
Cancer Radiother ; 23(2): 138-146, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30797691

RESUMO

PURPOSE: This study aimed to evaluate characteristics of dose fall-off pattern for linear accelerator based frameless stereotactic radiotherapy and radiosurgery using two different techniques, three-dimensional conformal radiotherapy and volumetric modulated arc therapy. MATERIALS AND METHODS: The data from thirty patients who underwent frameless stereotactic radiotherapy/radiosurgery were considered for this analysis. These included 11 patients treated using three-dimensional conformal radiation and 19 patients treated with volumetric modulated arc therapy. Dose fall-offs in six predetermined directions from the edge of planning target volume and in direction of organs at risk were evaluated. These included determining dose fall-off (distance range) of 100%-80%, 100%-50%, 100%-20% from the treatment planning system. The first derivative (percentage of dose fall-off per millimetre) and second derivative (percentage of dose per square millimetre) of the dose fall-off was calculated. RESULTS: The dose fall-off is sharpest in the organ at risk direction if the organ at risk is hugging the planning target volume. However, for organs at risk separated from the planning target volume sharpest dose fall-off could be in either planning target volume superior or inferior direction. Three-dimensional conformal radiotherapy plans had a mean±SD of 14±2 beams (range: 11-17). Volumetric modulated arc therapy planning comprised of arc angles with sum±SD of 953±172.5° (range: 610°-1170°). Mean±SD for the single sharpest dose fall-off for all patients receiving three-dimensional conformal radiotherapy was 11.3±4.7%·mm-1, 7.8±4.8%·mm-1 and 7.1±5.6%·mm-1 for 100%-80%, 100%-50% and 100%-20% fall-off ranges respectively. For volumetric modulated arc therapy, the mean±SD of the single sharpest fall-off was 10.4±4.6%·mm-1, 7.8±3.0%·mm-1 and 7.3±5.0%·mm-1 for 100%-80%, 100%-50% and 100%-20% range. All organs at risk doses received doses within limits prescribed by AAPM-TG report 21. Mean dose to monitor units (MU) modulation factor MF=totalMUdeliveredprescriptiondoseincGy for three-dimensional conformal radiotherapy and volumetric modulated arc therapy were 1.97±1.0 MU·cGy-1 and 2.5±0.75 MU·cGy-1 respectively. CONCLUSION: Our study presents the dose fall-off patterns in context of frameless stereotactic radiation therapy. We have presented the dose fall-off data in the framework of three-dimensional conformal radiotherapy and volumetric modulated arc therapy in brain lesions.


Assuntos
Órgãos em Risco , Radiocirurgia , Dosagem Radioterapêutica , Radioterapia Conformacional , Radioterapia de Intensidade Modulada , Adolescente , Adulto , Idoso , Neoplasias Encefálicas/radioterapia , Criança , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Planejamento da Radioterapia Assistida por Computador , Tomografia Computadorizada por Raios X , Adulto Jovem
18.
South Asian J Cancer ; 7(2): 118-122, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29721477

RESUMO

Breast cancer is a common cause of brain metastases, with metastases occurring in at least 10-16% of patients. Longer survival of patients with metastatic breast cancer and the use of better imaging techniques are associated with an increased incidence of brain metastases. Current therapies include surgery, whole-brain radiation therapy, stereotactic radiosurgery, chemotherapy and targeted therapies. However, the timing and appropriate use of these therapies is controversial and careful patient selection by using available prognostic tools is extremely important. Expert oncologist discussed on the mode of treatment to extend the OS and improve the quality of life ofHER2-positivebreast cancer patients with Solitary brain metastases. This expert group used data from published literature, practical experience and opinion of a large group of academic oncologists to arrive at this practical consensus recommendations for the benefit of community oncologists.

19.
Cancer Radiother ; 22(1): 62-72, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29195796

RESUMO

A technique using volumetric-modulated arc therapy (VMAT) fields for craniospinal irradiation with low dose gradients at the field junction was tested for its sensitivity to positional inaccuracy. It was compared against the conventional three-dimensional (3D) conformal radiotherapy in terms of dose uniformity at the junction. Treatment plans generated for ten patients who received craniospinal irradiation (35Gy in 21 fractions) by VMAT technique at our centre were included in this study. For these patients, 3D conformal radiotherapy plans were also generated in addition to the VMAT treatment plans. Intentional shifting of the cranial field in the superior and then in the inferior directions was done, creating a gap or overlap between the fields. Consequent changes in dose distributions in these two plans to positional inaccuracies were studied. The 3D conformal radiotherapy plans showed large dose variations at the junction due to positional shifts as compared to the VMAT plans. With a 5mm superior shift of the cranial field isocentre creating a gap between the cranial and spinal fields, the magnitudes of under-dosing were 13.9±3.6Gy and 4.8±2.0Gy for 3D conformal radiotherapy and VMAT respectively. When the cranial field was moved by 5mm inferiorly creating an overlap between the fields, overdose to the effects of 10.3±4.0Gy and 4.9±1.3Gy were observed for the 3D conformal radiotherapy plans and VMAT plans respectively. The VMAT technique is insensitive to longitudinal setup errors (1-3mm) in patients because of the existence of low dose gradients at the junction between fields. This is unlike the 3D conformal radiotherapy plans which have steep dose gradients at the field edges and thus are highly sensitive to setup errors. Such an advantage for VMAT circumvents the need for dose feathering often practiced with the 3D conformal radiotherapy technique and makes the technique simpler to follow.


Assuntos
Radiação Cranioespinal/métodos , Radioterapia de Intensidade Modulada/métodos , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Tomografia Computadorizada Multidetectores , Órgãos em Risco , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia Conformacional
20.
Indian J Cancer ; 54(1): 262-266, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29199702

RESUMO

BACKGROUND: Majority of patients of lung cancer present with locally advanced or metastatic disease, where systemic therapy is the treatment of choice. Many of these patients have local symptoms due to thoracic disease, wherein radiotherapy is proven to be an effective modality for alleviation of symptoms. However, the optimal dose of radiotherapy for adequate palliation remains debatable. The purpose of this retrospective study was to assess the efficacy of two different schedules of thoracic radiotherapy (TRT) with respect to symptom palliation. MATERIALS AND METHODS: A total of 100 consecutively treated patients with stages III-IV lung cancer treated with two different fractionation regimens of palliative TRT, either protracted course 20 Gy/5# over 1 week or short course of 17 Gy/2# over 8 days were assessed for symptom relief and survival. Impact of patient, tumor and treatment-related factors on response and overall survival (OS) was done by univariate analysis using log-rank test. RESULTS: Median age of the entire cohort was 60 years, majority being males, smokers with low Eastern Cooperative Oncology Group performance status (performance score ≥2). Predominant symptoms were chest pain (68) followed by cough (21) and dyspnea (15). Palliative TRT was offered as either protracted course 20 Gy/5# over 1 week or short course of 17 Gy/2# over 8 days in 21 and 79 patients respectively. Median duration of symptom relief was 2 months, no differences in OS at 1 year with either regimen. CONCLUSIONS: TRT is an effective means of palliation having similar symptom relief and outcomes with weekly (17 Gy/2# over 8 days) or protracted radiotherapy regimens (20 Gy/5#over 1 week). Short TRT schedules are convenient and economical for patients as well as resource sparing for high volume centers.


Assuntos
Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/radioterapia , Cuidados Paliativos , Adulto , Idoso , Idoso de 80 Anos ou mais , Fracionamento da Dose de Radiação , Feminino , Humanos , Índia/epidemiologia , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Dosagem Radioterapêutica
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