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1.
Med Dosim ; 47(2): 161-165, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35241348

RESUMO

The purpose of this work was to study the radiobiological effect of using Acuros XB (AXB) vs Analytic Anisotropic Algorithm (AAA) on hepatocellular carcinoma (HCC) stereotactic body radiation therapy (SBRT). Seventy SBRT volumetric modulated arc therapy (VMAT) plans for HCC were calculated using AAA and AXB respectively with the same treatment parameters. Published tumor control probability (TCP) and normal tissue complication probability (NTCP) models were used to quantify the effect of dosimetric difference between AAA and AXB on TCP, NTCP and uncomplicated tumor control probability (UTCP). There was an average decrease of 2.5% in 6-month TCP. Normal liver has the largest average decrease in NTCP which was 59.7%. Bowels followed with 26.6% average decrease in NTCP. Duodenum, stomach and esophagus had 10.2%, 5.1%, and 4.3% average decrease in NTCP. There was an average decrease of 1.8% and up to 7.2% in 6-month UTCP. There was an overall decrease in TCP, NTCP, and UTCP for HCC SBRT plans calculated using AXB compared to AAA which could be clinically significant.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Radiocirurgia , Algoritmos , Carcinoma Hepatocelular/radioterapia , Humanos , Neoplasias Hepáticas/radioterapia , Planejamento da Radioterapia Assistida por Computador
2.
J Cancer Res Clin Oncol ; 148(7): 1749-1759, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34363123

RESUMO

PURPOSE: Performance of 3D-T1W-TSE has been proven superior to 3D-MP-GRE at 3 T on brain metastases (BM) contrast-enhanced (CE) MRI. However, its performance at 1.5 T is largely unknown and sparsely reported. This study aims to assess image quality, lesion detectability and conspicuity of 1.5 T 3D-T1W-TSE on planning MRI of frameless BM radiotherapy. METHODS: 94 BM patients to be treated by frameless brain radiotherapy were scanned using 3D-T1W-TSE with immobilization on multi-vendor 1.5 T MRI-simulators. BMs were jointly diagnosed by 4 reviewers. Enhanced lesion conspicuity was quantitatively assessed by calculating contrast ratio (CR) and contrast-to-noise ratio (CNR). Signal-to-noise ratio (SNR) reduction of white matter due to the use of flexible coil was assessed. Lesion detectability and conspicuity were compared between 1.5 T planning MRI and 3 T diagnostic MRI by an oncologist and a radiologist in 10 patients. RESULTS: 497 BMs were jointly diagnosed. The CR and CNR were 75.2 ± 39.9% and 14.2 ± 8.1, respectively. SNR reduced considerably from 31.7 ± 8.3 to 21.9 ± 5.4 with the longer distance to coils. 3 T diagnostic MRI and 1.5 T planning MRI yielded exactly the same detection of 84 BMs. Qualitatively, lesion conspicuity at 1.5 T was not inferior to that at 3 T. Quantitatively, lower brain SNR and lesion CNR were found at 1.5 T, while lesion CR at 1.5 T was highly comparable to that at 3 T. CONCLUSION: 1.5 T 3D-T1W-TSE planning MRI of frameless BM radiotherapy was comprehensively assessed. Highly comparable BM detectability and conspicuity were achieved by 1.5 T planning MRI compared to 3 T diagnostic MRI. 1.5 T 3D-T1W-TSE should be valuable for frameless brain radiotherapy planning.


Assuntos
Neoplasias Encefálicas , Radioterapia (Especialidade) , Encéfalo , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/radioterapia , Meios de Contraste , Humanos , Imageamento por Ressonância Magnética/métodos
3.
Adv Radiat Oncol ; 6(5): 100739, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34355107

RESUMO

PURPOSE: This work was to establish an uncomplicated tumor control probability (UTCP) model using hepatocellular carcinoma (HCC) stereotactic body radiation therapy (SBRT) clinical data in our institution. The model was then used to analyze the current dose prescription method and to seek the opportunity for improvement. METHODS AND MATERIALS: A tumor control probability (TCP) model was generated based on local clinical data using the maximum likelihood method. A UTCP model was then formed by combining the established TCP model with the normal tissue complication probability model based on the study by Dawson et al. The authors investigated the dependence of maximum achievable UTCP on planning target volume equivalent uniform dose (EUD) at various ratio between planning target volume EUD and normal liver EUD (T/N EUD ratios). A new term uncomplicated tumor control efficiency (UTCE) was also introduced to analyze the outcome. A UTCE value of 1 implied that the theoretical maximum UTCP for the corresponding T/N EUD ratio was achieved. RESULTS: The UTCE of the HCC SBRT patients based on the current dose prescription method was found to be 0.93 ± 0.05. It was found that the UTCE could be increased to 0.99 ± 0.03 by using a new dose prescription scheme, for which the UTCP could be maximized while keeping the normal tissue complication probability value smaller than 5%. CONCLUSIONS: The dose prescription method of the current HCC SBRT in our institution was analyzed using a UTCP model established based on local clinical data. It was shown that there could be a potential to increase the prescription dose of HCC SBRT. A new dose prescription scheme was proposed to achieve better UTCP. Additional clinical trials would be required to validate the proposed dose prescription scheme in the future.

4.
Head Neck ; 43(6): 1711-1720, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33576030

RESUMO

BACKGROUND: The durability of improved xerostomia with intensity-modulated radiotherapy (IMRT) in patients with early stage nasopharyngeal carcinoma (NPC) is uncertain. We conducted a long-term prospective assessment of participants treated with IMRT or two-dimensional radiotherapy (2DRT) in a prior randomized study. METHODS: Parent study participants (IMRT, n = 28; 2DRT, n = 28) who were free of second malignancy or recurrence were eligible. Long-term radiotherapy-related toxicities were graded according to the Radiation Therapy Oncology Group (RTOG) criteria. Long-term patient-reported outcomes were assessed by the six-item xerostomia (XQ) and two European Organisation for Research and Treatment of Cancer (EORTC) questionnaires (QLQ-C30, QLQ-H&N35). Overall survival (OS), locoregional relapse-free survival (LRFS), distant relapse-free survival (DRFS), and the rate of symptomatic late complications (SLCs) were estimated for the entire cohort (n = 56). RESULTS: Totally, 21 (IMRT, n = 10; 2DRT, n = 11) patients gave consent and were assessed for an overall median follow-up of 15.5 years. There was significantly less RTOG ≥grade 2 xerostomia with IMRT versus 2DRT (20% vs. 90%; p = 0.001), but no significant difference in XQ scores. Patients in the IMRT arm reported lower mean scores for the "dry mouth" domain of EORTC QLQ-H&N35 (p = 0.02) and showed trends toward better 15-year OS (81.5% vs. 53.8%, p = 0.06), LRFS (70.6% vs. 53.8%, p = 0.38), and DRFS (81.5% vs. 53.8%, p = 0.07). SLCs were more frequent in the 2DRT arm. CONCLUSIONS: The parotid-sparing effect of IMRT in NPC treatment is durable, with significantly less physician- and patient-scored xerostomia at 15 years. IMRT results in better long-term survival and fewer SLCs.


Assuntos
Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Seguimentos , Humanos , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Recidiva Local de Neoplasia/radioterapia , Estudos Prospectivos , Radioterapia de Intensidade Modulada/efeitos adversos
5.
Int J Radiat Oncol Biol Phys ; 100(3): 630-638, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29413277

RESUMO

PURPOSE: To evaluate, in a phase 2 study, whether induction docetaxel, cisplatin, and fluorouracil (TPF) followed by weekly docetaxel and cetuximab in concurrence with intensity modulated radiation therapy can improve the treatment outcome for patients with advanced locally recurrent nasopharyngeal carcinoma (rNPC). METHODS AND MATERIALS: Thirty-three patients with rNPC (T3-T4, N0-N1, M0) were recruited. Of these, 19 patients (57.6%) had stage rT3 recurrence, and the rest had stage rT4. Eight patients also had rN1 at the time of relapse. Treatment outcomes and safety were evaluated. RESULTS: Among these 33 patients, 1 died after 1 cycle of TPF, 5 patients withdrew from the study during the induction period because of grade ≥3 toxicities; 27 patients completed the whole course of treatment, but 1 died before any assessment could be made. The median follow-up period was 28.5 months. The progression-free survival and overall survival at 3 years for the whole group were 35.7% and 63.8%, respectively. Among the 26 patients who could be assessed after treatment, the complete response rate was 30.8%, and the locoregional control rate at 3 years was 49.2%. Temporal lobe necrosis (TLN) developed in 8 cases. The rates of grade ≥3 hearing loss, soft tissue necrosis, dysphagia, and trismus were 30.8%, 15.4%, 11.5%, and 19.2%, respectively. Overall, 5 patients died owing to acute (1 after cycle 1 TPF and 1 after completion of bio-chemoradiotherapy) or late (2 epistaxis and 1 TLN) treatment-related complications. CONCLUSIONS: The proposed salvage treatment regimen for advanced locally recurrent NPC could achieve a better treatment outcome than seen in previous studies. However, poor tolerability of induction TPF and the high rate of TLN limit its applicability outside clinical trials.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia/métodos , Quimioterapia de Indução/métodos , Carcinoma Nasofaríngeo/terapia , Neoplasias Nasofaríngeas/terapia , Recidiva Local de Neoplasia/terapia , Radioterapia de Intensidade Modulada , Adulto , Idoso , Causas de Morte , Cetuximab/administração & dosagem , Quimiorradioterapia/efeitos adversos , Cisplatino/administração & dosagem , Docetaxel/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Humanos , Quimioterapia de Indução/efeitos adversos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/mortalidade , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Necrose/etiologia , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Intervalo Livre de Progressão , Estudos Prospectivos , Radioterapia de Intensidade Modulada/efeitos adversos , Terapia de Salvação/métodos , Lobo Temporal/patologia , Lobo Temporal/efeitos da radiação , Resultado do Tratamento
6.
Oral Oncol ; 69: 74-79, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28559024

RESUMO

PURPOSE: To determine if the magnetic resonance imaging (MRI) of the head and neck can predict distant metastases (DM) from nasopharyngeal carcinoma (NPC). METHODS AND MATERIALS: MRI examinations of 763 NPC patients were assessed for primary tumour stage (T), nodal stage (N), primary tumour volume (PTV) and total nodal volume (NV). The association between MRI and clinical parameters were examined in DM+ and DM- patients using logistic regression and for distant metastases free survival (DMFS) using cox regression. Optimum thresholds were assessed by receiver-operating characteristics analysis, and positive predictive value (PPV) and odds ratio (OR) calculated. RESULTS: Distant metastases were present in 181/763 NPC patients (23.7%). Higher N stage and NV were the independent predictors of DM (p<0.001 and 0.018 respectively) and poor DMFS (p=0.001 and 0.030 respectively). Addition of NV (threshold≥32.8cm3) to the N stage improved the PPVs and ORs for DM in stage N1 (from 18.9% to 31.8% and 5.613 to 11.133 respectively) and stage N2 (from 40.4% to 60.8% and 16.189 to 36.979 respectively) but not in stage N3 (68.3% to 68.6% and 51.385 to 52.052 respectively). CONCLUSION: MRI N stage and NV were independent predictors of DM and DMFS. The addition of NV in NPC patients with bulky N1 and N2 disease improved the ability of MRI to predict DM.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neoplasias Nasofaríngeas/patologia , Metástase Neoplásica/diagnóstico por imagem , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/diagnóstico por imagem , Prognóstico , Estudos Retrospectivos
7.
Eur Arch Otorhinolaryngol ; 274(2): 1045-1051, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27722898

RESUMO

Our study aimed to identify diffusion-weighted imaging (DWI) parameters obtained from primary nasopharyngeal carcinoma (NPC) at initial presentation, that can predict patients at risk of distant metastases. One hundred and sixty-four patients underwent pretreatment magnetic resonance imaging and DWI. The apparent diffusion coefficient (ADC)mean, ADCskewness, and ADCkurtosis were obtained by histogram analysis. Univariate and multivariate analyses of these ADC parameters together with primary volume (PV), nodal volume (NV), T stage, N stage and presence of locoregional relapse (LRR) were compared between patients with distant metastases (DM+) and patients without distant metastases (DM-) at 5 years using logistic regression. Twenty-eight out of 164 patients (17.1 %) were DM+ (2.5-60 months) and 136/164 patients were DM- (61.2-119.4 months). Compared to DM- patients, the primary tumour of DM+ patients showed significantly lower ADCskewness (ADC values with the greatest frequency were higher) (p = 0.041), and higher PV (p = 0.022), NV (p < 0.01), T stage (p = 0.023), N stage (p < 0.01) and LRR (p < 0.01). On multivariate analysis the ADCskewness was no longer significant (p = 0.120) and only NV and LRR were independent predictors for DM+ (p = 0.023 and 0.021, respectively). DWI showed that compared to DM- patients, DM+ patients had a significantly lower primary tumour ADCskewness, but at initial presentation NV was the only independent predictor of DM.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/secundário , Nasofaringe/diagnóstico por imagem , Estadiamento de Neoplasias/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Metástase Neoplásica , Valor Preditivo dos Testes
8.
Surg Neurol Int ; 7: 92, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27857856

RESUMO

BACKGROUND: Pattern of recurrence of glioblastoma (GBM) seems to have undergone some shifts from distant metastasis as a rarity to a higher proportion, including disease disseminated via cerebrospinal fluid (CSF) pathway. There is still no report on the pattern of recurrence for Chinese population. Here, we evaluated the pattern of recurrence of GBM in Chinese patients along with factors that could affect the distribution of recurrence. METHODS: Medical records of GBM patients with definite recurrence were reviewed. Local recurrence was defined as tumor regrowth within the preoperative abnormal signals on magnetic resonance imaging (MRI) T2 sequence. New recurrence was a new lesion away from the preoperative T2 abnormalities. New recurrence in contact with CSF pathways was registered as new CSF dissemination. Progress-free survival (PFS) and survival after progress were compared using the Kaplan-Meier survival curves. Potential risk factors for new CSF dissemination were assessed using univariate models followed by multivariate analysis. RESULTS: Thirty-six patients were proven to have recurrence; 22 local and 14 new recurrences. Among the 14 patients, 11 had new CSF dissemination. Median PFS for local, new parenchymal recurrence, and new CSF dissemination were 5.5 months, 9.9 months, and 12.1 months, whereas survival after progress were 6.1 months, 5.7 months, and 16.9 months, respectively. The ventricular entry during surgery and the completion of concomitant chemoradiotherapy were risk factors for new CSF dissemination. O6-methylguanine-DNA methyltransferase methylation was associated with the development of CSF dissemination. CONCLUSION: The majority of recurrence remained local (22/36, 61%). However, CSF dissemination was up to 30% (11/36). PFS for patients with CSF dissemination was the longest, and paradoxically survival after progress was the shortest. Ventricular entry should be avoided. Whole craniospinal MRI surveillance should be included for these patients.

9.
Cancer ; 121(16): 2720-9, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25946469

RESUMO

BACKGROUND: Single nucleotide polymorphism (SNP) of the excision repair cross-complementing group 1 (ERCC1) gene has been linked with sensitivity to platinum and radiation. The authors hypothesized that the ERCC1 genotype for the SNPs cytosine-to-thymine substitution at codon 118 (C118T) and cytosine-to-adenine substitution at codon 8092 (C8092A) is prognostic in patients with nasopharyngeal carcinoma (NPC) who receive either radiotherapy (RT) or cisplatin plus RT. METHODS: The authors tested their hypothesis using biomarker screening samples from the Hong Kong NPC Study Group 0502 trial, which was a prospective, multicenter clinical trial that used post-RT plasma Epstein-Bar virus (EBV) DNA (pEBV) levels to screen patients with high-risk NPC for adjuvant chemotherapy. RESULTS: ERCC1 SNPs were analyzed in 576 consecutive patients who were screened by pEBV. In the total biomarker population, there was no significant association of ERCC1 C118T or C8092A genotype with relapse-free survival (RFS) or overall survival (OS). There also was no correlation between ERCC1 genotype and ERCC1 protein or messenger RNA expression in a subset of patients who had available paired biopsies. Post-RT pEBV status was the only independent prognosticator for RFS and OS in multivariate analyses. However, there was a significant interaction between ERCC1 C118T genotype and post-RT pEBV status (RFS, P = .0106; OS, P = .0067). The ERCC1 C118T genotype was significantly associated with both RFS (hazard ratio, 1.67; 95% confidence interval, 1.07-2.61; P = .024) and OS (hazard ratio, 2.31; 95% confidence interval, 1.22-4.40; P = .0106) in the post-RT pEBV-negative population, but not in the pEBV-positive population. CONCLUSIONS: The current results prospectively validate pEBV as the most significant prognostic biomarker in NPC that can be used to select high-risk patients for adjuvant therapy. The ERCC1 C118T genotype may help to identify a favorable subgroup (approximately 7%) of pEBV-negative patients with NPC who have an excellent prognosis and can be spared the toxicities of further therapy.


Assuntos
DNA Viral/sangue , Proteínas de Ligação a DNA/genética , Endonucleases/genética , Herpesvirus Humano 4/isolamento & purificação , Neoplasias Nasofaríngeas/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Carcinoma , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/virologia , Estudos Prospectivos
10.
Hong Kong Med J ; 20(6): 529-36, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25256817

RESUMO

Stereotactic ablative radiotherapy has emerged as a standard treatment for medically inoperable stage I non-small-cell lung cancer and selected cases of lung metastasis. Techniques to freeze or limit tumour movement during treatment and image-guided radiation delivery are integral to a successful stereotactic ablative treatment without overdose of surrounding normal structures. In this article, the practice in a local oncology institution will be used to illustrate the concept of personalised stereotactic ablative radiotherapy.


Assuntos
Neoplasias Pulmonares/cirurgia , Humanos , Neoplasias Pulmonares/patologia , Estadiamento de Neoplasias , Cuidados Paliativos , Radiocirurgia
11.
Oral Oncol ; 50(10): 907-12, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24126221

RESUMO

Radiotherapy has a good track record in the treatment of NPC, yet the late toxicity profile and local failure rate for locally advanced disease remain a concern. Modern RT techniques incorporating IMRT and IGRT have widened our potential in treating NPC more effectively, and shall be regarded as the standard of care. Out of the various dose fractionation regimens in IMRT, 70 Gy in 35 fractions or the mini-SIB proves to be safe in combination with chemotherapy, but any further attempt of dose escalation must be tried out with extreme caution to avoid severe toxicities. CT-MRI image fusion improves the accuracy of GTV delineation, whereas the role of PET-CT has yet to be verified. RTOG definition of the CTV provides a reasonable template for the inclusion of sites at risk of microscopic involvement, and fine tuning has to be made in the future based on careful analysis of the pattern of local failure with long term follow-up. Toxicity reduction via radiation volume or dose reduction is tempting, but once again it has to be tested under scrutiny. Retrospective data have emerged that suggest a benefit of using adaptive IMRT replanning in NPC, however the optimal timing or frequency of replanning is still unclear. Future prospective studies are thus required to evaluate the cost-effectiveness of adaptive RT and streamline the workflow logistics before it can be widely accepted in routine practice.


Assuntos
Neoplasias Nasofaríngeas/radioterapia , Fracionamento da Dose de Radiação , Humanos , Imageamento por Ressonância Magnética , Imagem Multimodal , Neoplasias Nasofaríngeas/patologia , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X
12.
J Clin Neurosci ; 19(9): 1252-4, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22784875

RESUMO

The modified radiosurgery-based arteriovenous malformation (AVM) score (modified AVM score or Pollock-Flickinger AVM score [PFAS]) is a simplified grading system developed to predict outcome after gamma knife radiosurgery for cerebral AVM. The purpose of this study was to test the PFAS in a cohort of patients managed with linear accelerator (LINAC) radiosurgery. We analyzed 70 consecutive patients with cerebral AVM treated with LINAC radiosurgery in Hong Kong. The scores were determined by the following equation: Modified AVM score=(0.1×volume [cm(3)])+(0.02×age [years])+(0.5×location). The location values are as follows: hemispheric/corpus callosum/cerebellar=0; basal ganglia/thalamus/brainstem=1. A total of 74% of patients presented with ruptured AVM before radiosurgery. The overall obliteration rate was 86%. Five (7%) patients developed new permanent neurological deficits from delayed bleeding or radiation-induced complications. Modified AVM score correlated with the percentage of patients with AVM obliteration without new neurological deficits (≤1, 96%; 1.01-1.50, 78%; 1.51-2.00, 90%; >2, 50%; Spearman's rho 0.354, p=0.003). In conclusion, the modified AVM score is a good predictor of patient outcome after LINAC radiosurgery in our cohort. The modified AVM score can be used to guide treatment selection for cerebral AVM and stratify patients for future comparative analyses.


Assuntos
Malformações Arteriovenosas Intracranianas/diagnóstico , Malformações Arteriovenosas Intracranianas/cirurgia , Radiocirurgia/métodos , Idoso , Angiografia Cerebral , Estudos de Coortes , Feminino , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Aceleradores de Partículas , Radiocirurgia/instrumentação , Reprodutibilidade dos Testes , Resultado do Tratamento
13.
Hong Kong Med J ; 18(3): 221-5, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22665686

RESUMO

OBJECTIVES: To investigate the frequency of pseudoprogression of glioblastoma in Chinese patients receiving concomitant chemoradiotherapy and investigate its association with pseudoprogression and tumour molecular marker O(6)-methylguanine-DNA methyltransferase promoter methylation status. DESIGN: Case series with internal comparisons. SETTING: University teaching hospital, Hong Kong. PATIENTS: Patients with glioblastoma treated with concomitant chemoradiotherapy during April 2005 to June 2010 were reviewed. Magnetic resonance imaging brain scans, pre- and post-concomitant chemoradiotherapy and 3-monthly thereafter were reviewed by an independent neuroradiologist according to Macdonald's criteria. Relevant patient information (clinical condition, performance score, development of new neurological deficits, use of steroids, and survival) was retrieved. For each patient, O(6)-methylguanine-DNA methyltransferase methylation status was investigated with genomic DNA from formalin-fixed or paraffin-embedded sections of tumour tissues by methylation-specific polymerase chain reaction. RESULTS: During the study period, 28 primary glioblastoma patients underwent concomitant chemoradiotherapy. The mean age of the patients was 48 (range, 16-71) years. Thirteen patients (13/28, 46%) developed early radiological progression of the tumour after completion of concomitant chemoradiotherapy, of whom five (39%) were subsequently found to have had pseudoprogression. Patients with pseudoprogression showed a trend towards longer survival (22 months in pseudoprogression vs 17 months in all others vs 11 months in those with genuine progression). Among the 27 patients tested for O(6)-methylguanine-DNA methyltransferase promoter status, 12 (44%) were methylated. Two (2/12, 17%) in the methylated group had pseudoprogression, while three (3/15, 20%) in the unmethylated group had pseudoprogression. CONCLUSIONS: Nearly half of all patients (46%) developed early radiological progression (within 3 months of completing concomitant chemoradiotherapy). Moreover, about one in three of such patients had pseudoprogression. Pseudoprogression is an important clinical condition to be aware of to prevent premature termination of an effective treatment.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/terapia , Metilases de Modificação do DNA/genética , Glioblastoma/terapia , Glioma/terapia , O(6)-Metilguanina-DNA Metiltransferase/genética , Adolescente , Adulto , Idoso , Antineoplásicos Alquilantes/efeitos adversos , Povo Asiático , Biomarcadores Tumorais , Neoplasias Encefálicas/genética , Quimiorradioterapia , Metilação de DNA , Progressão da Doença , Glioblastoma/genética , Glioma/genética , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
14.
Head Neck ; 33(8): 1126-31, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21755557

RESUMO

BACKGROUND: The purpose of this study was to identify independent prognostic factors that influenced local relapse-free survival (LRFS) and overall survival (OS) of patients who underwent salvage surgery for residual or recurrent nasopharyngeal carcinoma (NPC). METHODS: Ninety-seven patients who had been treated with radiotherapy or chemoradiotherapy for NPC underwent a nasopharyngectomy for a residual or recurrent local tumor between November 1987 and June 2007. The subsequent minimum follow-up was 2 years. Univariate and multivariate analyses were performed to identify prognostic factors for LRFS and OS. RESULTS: The 5-year LRFS and OS was 46.7% and 51.9%, respectively. On multivariate analysis for LRFS and OS, respectively, recurrent regional disease (hazard ratio [HR], 3.245; p = .008) and (HR, 4.990; p = .001), and positive surgical margins (HR, 5.963; p = .000), and (HR, 4.912; p = .000) were independent prognostic factors. CONCLUSION: In patients undergoing surgical salvage nasopharyngectomy for residual or recurrent NPC, positive surgical margins have an independent negative influence on LRFS and OS.


Assuntos
Neoplasias Nasofaríngeas/terapia , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/cirurgia , Faringectomia/métodos , Terapia de Salvação/métodos , Adulto , Idoso , Análise de Variância , Biópsia por Agulha , Carcinoma , Quimiorradioterapia/métodos , Estudos de Coortes , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Neoplasia Residual , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
15.
Hong Kong Med J ; 17(3): 184-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21636865

RESUMO

OBJECTIVES: (1) To compare the survival of concomitant chemotherapy and radiotherapy with radiotherapy alone in Chinese patients with primary glioblastoma. (2) To determine the methylation status of O(6)Methylguanine DNA methyltransferase in Chinese primary glioblastoma, and to assess the prognostic value of O(6)Methylguanine DNA methyltransferase methylation status in such patients. DESIGN: Retrospective correlative analysis. SETTING: University teaching hospital, Hong Kong. PATIENTS: Patients diagnosed with histologically proven primary glioblastoma in the period of March 2005 to June 2007 were recruited. Genomic DNA was isolated from formalin-fixed and paraffin-embedded sections of glioblastoma tissues. Methylation-specific polymerase chain reaction for O(6)Methylguanine DNA methyltransferase was performed. Patients' information at presentation was collected (age, performance status, steroid use, extent of resection, complications, radiotherapy data, use of chemotherapy). Primary outcome was measured by overall survival while secondary outcome was measured by progression-free survival. Overall and progression-free survivals were estimated by the Kaplan-Meier technique. Outcomes were assessed for groups with and without concomitant chemoradiotherapy and for groups with and without O(6)Methylguanine DNA methyltransferase methylation. RESULTS: A total of 35 glioblastoma patients were recruited; 27 were male and 8 female. Their mean age was 50 years. In all, 17 received concomitant chemoradiotherapy, and 18 received radiotherapy only. Their median overall survival was 12 (range, 7-17) months and the median progression-free survival was 5 (range, 3-6) months. In the radiotherapy alone group, the median progression-free survival and overall survival was 4 (range, 3-5) months and 6 (range, 2-10) months, respectively. In the concomitant radiochemotherapy group, the median progression-free survival and overall survival was 6 (range, 2-10) months and 13 (range, 8-18) months, respectively. Fifteen (43%) of the tumour samples showed methylation of O(6)Methylguanine DNA methyltransferase. There was a trend towards overall longer survival in the group with methylated tumours compared to those with unmethylated tumours; respective values for median survival (ranges) were 17 (13-21) versus 10 (6-14) months (P=0.105). CONCLUSIONS: Our single-centre results indicated that Chinese glioblastoma patients who had received concomitant chemoradiotherapy showed a trend towards longer overall survival compared to those receiving radiotherapy alone. Approximately 43% of our Chinese glioblastoma samples showed methylation of O(6)Methylguanine DNA methyltransferase. O(6)Methylguanine DNA methyltransferase methylation may be a significant prognostic factor in Chinese glioblastoma patients.


Assuntos
Metilação de DNA , Glioblastoma/radioterapia , O(6)-Metilguanina-DNA Metiltransferase/genética , Povo Asiático , Quimioterapia Adjuvante/métodos , Terapia Combinada , Intervalo Livre de Doença , Feminino , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Hong Kong , Hospitais Universitários , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
16.
Head Neck ; 32(7): 913-20, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19885925

RESUMO

BACKGROUND: This study was established to determine the maximum tolerated dose of intra-arterial cisplatin (IAC) concurrent with accelerated fractionation radiotherapy for locally advanced head and neck squamous cell carcinoma (HNSCC). METHODS: We conducted a phase I study. Treatment consisted of 70 Gy/35 fractions/5.8 weeks and 2 weekly IAC infusions during the last 2 weeks. RESULTS: Ten patients were recruited. Two patients had stage III, 1 had stage IVa, and 7 had stage IVb disease. Three patients received IAC at 100 mg/m(2), 3 at 125 mg/m(2), and 4 at 150 mg/m(2). Nine patients received both planned infusions. Dose-limiting toxicity occurred at 150 mg/m(2) as transient grade 4 leukopenia and prolonged grade 3 acute skin reactions. The maximum tolerated dose was 125 mg/m(2). Six patients survived disease-free at 39 to 67 months. CONCLUSIONS: It was feasible to give IAC concurrent with accelerated fractionation radiotherapy for locally advanced HNSCC. The maximum tolerated dose of cisplatin was 125 mg/m(2).


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma de Células Escamosas/terapia , Cisplatino/administração & dosagem , Neoplasias de Cabeça e Pescoço/terapia , Adulto , Idoso , Antineoplásicos/efeitos adversos , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Cisplatino/efeitos adversos , Terapia Combinada , Fracionamento da Dose de Radiação , Relação Dose-Resposta a Droga , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Infusões Intra-Arteriais , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Estadiamento de Neoplasias
17.
Hong Kong Med J ; 15(5): 359-64, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19801693

RESUMO

OBJECTIVE: To review the experience with Onyx embolisation of cerebral arteriovenous malformation. DESIGN: Prospective study. SETTING: A regional neurosurgical centre in Hong Kong. PATIENTS: Data of patients with cerebral arteriovenous malformation who underwent Onyx embolisation over a 14-month period were prospectively collected. RESULTS: Eleven sessions of Onyx embolisation were performed in nine patients with cerebral arteriovenous malformations, seven of which had ruptured. Total occlusion was achieved in three (33%) of the patients, and subtotal occlusion (over 80% occlusion) in three out of four with Spetzler-Martin grade-III/IV malformations. One patient developed mild permanent neurological deficit. CONCLUSION: Onyx embolisation of cerebral arteriovenous malformations is feasible in Hong Kong. Careful patient and target selection are important.


Assuntos
Dimetil Sulfóxido/uso terapêutico , Embolização Terapêutica/métodos , Malformações Arteriovenosas Intracranianas/terapia , Polivinil/uso terapêutico , Adolescente , Adulto , Feminino , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
18.
Otolaryngol Head Neck Surg ; 139(1): 40-6, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18585559

RESUMO

OBJECTIVE: To investigate whether the approach used to the nasopharynx to perform a salvage nasopharyngectomy for recurrent or residual nasopharyngeal carcinoma influences survival. STUDY DESIGN: A retrospective case series. SUBJECTS AND METHODS: Eighty patients underwent a nasopharyngectomy via a transpalatal, maxillary swing, or midfacial degloving approach. Local progression-free, locoregional progression-free, and overall survival rates were calculated for each approach. RESULTS: For the whole group (N = 80), there were no significant differences in the survival rates between the three approaches. For the subgroup of patients with recurrent T1 and T2 tumors (n = 68), the local progression-free and locoregional progression-free survival rates were significantly better when a maxillary swing approach was used than when a midfacial degloving approach was used. CONCLUSION: The maxillary swing approach is associated with significantly better survival rates than the midfacial degloving approach when used to perform a salvage nasopharyngectomy for residual or recurrent T1 and T2 nasopharyngeal carcinoma.


Assuntos
Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/cirurgia , Nasofaringe/cirurgia , Adulto , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Otorrinolaringológicos/métodos , Terapia de Salvação , Taxa de Sobrevida
19.
Arch Otolaryngol Head Neck Surg ; 133(12): 1296-301, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18086975

RESUMO

OBJECTIVE: To explore whether the margin status at surgical salvage nasopharyngectomy for local residual or recurrent nasopharyngeal carcinoma affects patient survival. DESIGN: Retrospective case series review. SETTING: Academic tertiary referral center. PATIENTS: Seventy-nine consecutive patients with operable local residual or recurrent nasopharyngeal carcinoma after failure of primary treatment with radiotherapy with or without chemotherapy underwent surgical salvage nasopharyngectomy with curative intent between November 28, 1987, and November 17, 2003. Sixty-one patients were men and 18 were women. Their mean age was 48 years (age range, 26-70 years). INTERVENTION: Surgical salvage nasopharyngectomy. MAIN OUTCOME MEASURES: The status of the closest margin at surgery was assessed as clear, close, or positive. Survival time was measured from the date of surgery to the date of the last follow-up, to the date of an event occurrence, or to the date of death. The Kaplan-Meier method was used to estimate the probability of local progression-free survival and overall survival at 5 years. Differences in survival rates between surgical margin statuses were assessed using the log-rank test. RESULTS: Five-year overall survival for patients with clear margins was 77%, for patients with close margins was 46% (P = .05), and for patients with positive margins was 23% (P < .001). CONCLUSION: Clear surgical margins at the time of surgical salvage nasopharyngectomy for residual or recurrent nasopharyngeal carcinoma positively affect patient survival.


Assuntos
Neoplasias Nasofaríngeas/mortalidade , Nariz/cirurgia , Faringectomia/métodos , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Seguimentos , Hong Kong/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/cirurgia , Estudos Retrospectivos , Análise de Sobrevida , Taxa de Sobrevida/tendências , Resultado do Tratamento
20.
J Clin Oncol ; 25(31): 4873-9, 2007 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17971582

RESUMO

PURPOSE: This randomized trial compared the rates of delayed xerostomia between two-dimensional radiation therapy (2DRT) and intensity-modulated radiation therapy (IMRT) in the treatment of early-stage nasopharyngeal carcinoma (NPC). PATIENTS AND METHODS: Between November 2001 and December 2003, 60 patients with T1-2bN0-1M0 NPC were randomly assigned to receive either IMRT or 2DRT. Primary end point was incidence of observer-rated severe xerostomia at 1 year after treatment based on Radiotherapy Oncology Group /European Organisation for the Research and Treatment of Cancer late radiation morbidity scoring criteria. Parallel assessment with patient-reported outcome, stimulated parotid flow rate (SPFR), and stimulated whole saliva flow rate (SWSFR) were also made. RESULTS: At 1 year after treatment, patients in IMRT arm had lower incidence of observer-rated severe xerostomia than patients in the 2DRT arm (39.3% v 82.1%; P = .001), parallel with a higher fractional SPFR (0.90 v 0.05; P < .0001), and higher fractional SWSFR (0.41 v 0.20; P = .001). As for patient's subjective feeling, although a trend of improvement in patient-reported outcome was observed after IMRT, recovery was incomplete and there was no significant difference in patient-reported outcome between the two arms. CONCLUSION: IMRT is superior to 2DRT in preserving parotid function and results in less severe delayed xerostomia in the treatment of early-stage NPC. Incomplete improvement in patient's subjective xerostomia with parotid-sparing IMRT reflects the need to enhance protection of other salivary glands.


Assuntos
Neoplasias Nasofaríngeas/radioterapia , Radioterapia de Intensidade Modulada , Glândulas Salivares/efeitos da radiação , Adulto , Idoso , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Radioterapia de Intensidade Modulada/efeitos adversos , Glândulas Salivares/fisiopatologia , Xerostomia/epidemiologia , Xerostomia/etiologia
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