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1.
Ann N Y Acad Sci ; 945: 73-9, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11708497

RESUMO

Nineteen consecutive patients with metastatic or recurrent nasopharyngeal cancer (NPC) receiving combination chemotherapy were monitored for EBV DNA in their serum. EBV DNA (EBER-1) concentration in serum was measured before, during, and after chemotherapy. Thirteen patients had additional multiple prechemotherapy readings. There was a significant lead time from first detection of serum EBER-1 to clinical recurrence in 62% of patients by a mean of 17.4 weeks (range: 8-74.5 weeks; mean = 28.2 weeks if confined to the 8 patients with significant lead time). The median EBER-1 concentration was significantly higher in those with distant metastasis as compared to those with loco-regional recurrence only (17,468 vs. 684 pg/mL serum; p = 0.046, Mann-Whitney U test). Among the 13 patients who responded to chemotherapy, 4 exhibited clinical complete remission (CR) who were only found in the group with EBER-1 DNA drop to background level, while the magnitude of EBER-1 drop did not discriminate partial remission (PR) and stable disease (SD) patients clearly. Subsequent profile of EBER-1 DNA showed concordance with clinical course of either continuous remission or later progression. EBER-1 DNA in serum can become a useful adjunctive surrogate marker to monitor chemotherapeutic response in NPC patients with distant metastasis or advanced local recurrence.


Assuntos
Herpesvirus Humano 4/genética , Neoplasias Nasofaríngeas/tratamento farmacológico , RNA Viral/sangue , Terapia de Salvação , DNA Viral/sangue , Humanos , Monitorização Fisiológica , Neoplasias Nasofaríngeas/sangue , Neoplasias Nasofaríngeas/virologia , Resultado do Tratamento
2.
Chemistry ; 7(22): 4928-36, 2001 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-11763461

RESUMO

We present transient-resonance Raman spectra for the 4-biphenylylnitrenium, diphenylnitrenium, and 2-fluorenylnitrenium ions. These spectra display a number of fundamental vibrational bands whose frequencies exhibit good agreement with those computed using BPW91/cc-PVDZ density functional theory calculations for the singlet ground states of the 4-biphenylylnitrenium, diphenylnitrenium, and 2-fluorenylnitrenium ions. Comparison of these arylnitrenium ions with each other and with previous results for structurally similar biphenyl radical cations indicates that the degree of iminocyclohexadienyl character observed in these arylnitrenium ions depends on the relative orientation of the two phenyl rings, the nature of the nitrenium ion moiety, and the ability of the biphenyl-like group to accommodate positive charge through formation of a more planar-like structure with quinoidal-like character.

3.
Int J Radiat Oncol Biol Phys ; 46(4): 865-72, 2000 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-10705007

RESUMO

PURPOSE: To assess the additional damage of normal tissues attributable to reirradiation and the magnitude of partial recovery following the initial course. METHODS AND MATERIALS: Symptomatic late complication rates (excluding xerostomia) in 3635 patients receiving one course (Group 1) and 487 patients receiving two courses of external radiotherapy (Group 2) for nasopharyngeal carcinoma were retrospectively analyzed and compared. RESULTS: Group 2 had significantly lower actuarial complication-free survival rates than Group 1: 48% versus 81% at 5 years. The post-retreatment incidence was significantly affected by biologically effective dose (BED) (assuming an alpha/beta ratio of 3 Gy) of the first course: hazard ratio (HR) = 1.04 per Gy(3) (p = 0.01), but only marginally by that of the second course: HR = 1.01 per Gy(3) (p = 0.06). If the summated BED was taken as the dose unit, it was estimated that a total BED of 143 Gy(3) would induce a 20% incidence at 5 years, while the corresponding dose projected from Group 1 was 111 Gy(3). The gap effect was insignificant in the overall analyses, but a trend of decreasing risk with increasing interval was observed in patients with gap > or = 2 years: HR = 0.86 per year (p = 0.07). CONCLUSION: The major determinant of post-retreatment complication is the severity of damage during the initial course. The sum of total doses tolerated is higher than that expected with a single-course treatment, suggesting occurrence of partial recovery (particularly in those reirradiated after an interval of 2 years or more).


Assuntos
Neoplasias Nasofaríngeas/radioterapia , Lesões por Radiação/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Criança , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Lesões por Radiação/patologia , Tolerância a Radiação , Dosagem Radioterapêutica , Eficiência Biológica Relativa , Estudos Retrospectivos
4.
Int J Radiat Oncol Biol Phys ; 44(1): 149-56, 1999 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10219808

RESUMO

PURPOSE: To study the peculiar characteristics of relapses with long latency following radical treatment for nasopharyngeal carcinoma. METHODS AND MATERIALS: 847 patients with nasopharyngeal recurrence were retrospectively studied, focusing on the independent effects of latency on different outcome aspects and its relationship with other prognostic factors. RESULTS: The proportion of recurrence with latency <2 years (Group A), 2-<5 years (Group B), and 25 years (Group C) were 52%, 39%, and 9%, respectively. A higher proportion of Group C originated from patients with node-negative early primary, but fewer of them were still confined within the nasopharynx at detection of recurrence. There was no significant difference in the choice of salvage modality, but among those reirradiated, more of Group C were treated with external beams to a higher dose. The difference in local salvage rate was not statistically significant, but the 5-year distant failure-free rates of the 3 groups were 57%, 67%, and 83%, respectively; and the corresponding disease-specific survival (DSS) were 14%, 20%, and 35%. Multivariate analysis confirmed the independent significance of latency in predicting distant failure (hazard ratio = 0.81 per year, p < 0.01) and cancer deaths (hazard ratio = 0.90 per year, p < 0.01). CONCLUSIONS: Nasopharyngeal recurrence with long latency showed different natural behavior: the prognosis was significantly better due to lower risk of distant failure.


Assuntos
Neoplasias Nasofaríngeas/fisiopatologia , Neoplasias Nasofaríngeas/radioterapia , Recidiva Local de Neoplasia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Intervalo Livre de Doença , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Estadiamento de Neoplasias , Prognóstico , Radioterapia/métodos , Estudos Retrospectivos , Fatores de Tempo
5.
Int J Cancer ; 84(2): 179-87, 1999 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-10096252

RESUMO

The independent significance of different tumor factors in 4,514 patients with undifferentiated or non-keratinizing carcinoma of the nasopharynx irradiated at the Queen Elizabeth Hospital during 1976-1985 were analyzed retrospectively. Multivariate analyses showed that the most significant primary factors included cranial nerve palsy, erosion of base of skull and oropharynx. For tumors within the nasopharynx, there was no difference in survival between those with involvement of 1 site vs. more than 1 sites. Patients with cranial nerve palsy had significantly worse prognosis than those with bony erosion alone. Although the nodal characteristics (size, level of extension, fixation, laterality and multiplicity) were inter-related, their independent impact all reached statistical significance. However, the criteria used currently could be simplified: laterality should be revised to unilateral vs. bilateral, level to upper-mid vs. lower neck, and size to < or =6 cm vs. >6 cm. Grouping of N2 together with N3 into Stage IV was inappropriate as the former had significantly better prognosis. Our findings, together with review of the publications, provided clinical data for developing the current UICC staging system for nasopharyngeal carcinoma. Such major revision resulted not only in better distinction of hazards, but also more even distribution of cases between different stages.


Assuntos
Carcinoma/patologia , Neoplasias Nasofaríngeas/patologia , Estadiamento de Neoplasias/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Carcinoma/complicações , Carcinoma/mortalidade , Carcinoma/radioterapia , Criança , Doenças dos Nervos Cranianos/etiologia , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/complicações , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/radioterapia , Invasividade Neoplásica , Paralisia/etiologia , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Tempo
6.
Cancer ; 83(11): 2284-92, 1998 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9840527

RESUMO

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a prevalent malignant tumor among Southern Chinese. Previously, the authors described the prognostic significance of a serum antibody assay to a recombinant Epstein-Barr virus Bam HI-Z replication activator protein (ZEBRA) in NPC patients with long term follow-up. In this study, the authors further reported the use of DNA flow cytometry (DNA-FCM) as an additional technique for determining the prognosis of NPC patients in the same series. METHODS: One hundred and forty-three archival biopsies from 110 NPC patients were deparaffinized and subjected to DNA-FCM analysis. DNA ploidy state and various proliferative indices (PI) of the tumors were correlated with patient survival and frequency of recurrence. RESULTS: Among the biopsies analyzed, 119 were histologically positive NPC and 24 were negative. Fifty-one tumor biopsies that fulfilled the guideline criteria of the DNA Cytometry Consensus Conference were correlated with the clinical manifestations of the patients. Among them, 43 tumors (84%) were DNA diploid and 8 (16%) were aneuploid. Two PI, S-phase fraction (SPF) and proliferation fraction (PF), appear to be potentially useful prognostic indicators. For example, PF in patients who developed locoregional recurrence (15.1%) and distant recurrence (16.4%) after radiation therapy both were significantly higher than PF in patients who were in complete remission (8.2%) (P = 0.0005 and P = 0.004, respectively). Significant differences in SPF between patients with distant recurrence (10.6%) and those in remission (5.7%) also was found (P = 0.005). Using Kaplan-Meier analysis, patients with high PF, high SPF, and aneuploid tumors had significantly poorer 12-year survival rates (35%, 26%, and 28%, respectively) than those patients with low PF, low SPF, and diploid tumors (77%, 67%, and 59%, respectively) (P < 0.0009, P < 0.004, and P < 0.01, respectively). CONCLUSIONS: Determination of tumor PI and DNA ploidy state by DNA-FCM at diagnosis of NPC can be potentially useful in selecting a poor prognostic subgroup of NPC patients. These parameters may enable oncologists to plan for more stringent treatment strategies such as hyperfractionated and accelerated radiation therapy or concomitant chemoradiotherapy for these patients.


Assuntos
DNA de Neoplasias/genética , Neoplasias Nasofaríngeas/genética , Biópsia , Divisão Celular/fisiologia , Citometria de Fluxo , Humanos , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Ploidias , Prognóstico , Fase S , Taxa de Sobrevida
7.
Int J Radiat Oncol Biol Phys ; 40(1): 35-42, 1998 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-9422555

RESUMO

PURPOSE: To study the relative effects of different radiation factors on temporal lobe necrosis (TLN) and predictive accuracy of different biological equivalent models. METHODS AND MATERIALS: Consecutive patients (1008) treated radically with four different fractionation schedules during 1976-1985 for T1 nasopharyngeal carcinoma were retrospectively analyzed. All were irradiated by megavoltage photons using the same technique. Their age ranged from 18-84 years, and 92% of patients had complete follow-up. The fractional dose to inferomedial parts of both temporal lobes ranged from 2.5-4.2 Gy, total dose 45.6-60 Gy, and overall time 38-75 days. RESULTS: Despite a lower total dose of 50.4 Gy, the 621 patients irradiated with 4.2 Gy per fraction had a significantly higher incidence of temporal lobe necrosis than the 320 patients treated to 60 Gy with 2.5 Gy per fraction: the 10-year actuarial incidence being 18.6% vs. 4.6%, p < 0.001. Multivariate survival analysis showed that fractional effect (product of total dose and fractional dose) was the most significant factor: p = 0.0022, hazard ratio (HR) = 1.044 per Gy2. Overall time and age were both insignificant. The alpha/beta ratio calculated from our data was 2.9 Gy (95% CI: -1.8, 7.6 Gy). Biological effective dose (BED(Gy3)), neuret, and brain tolerance unit all showed strongly significant correlation with the necrotic rate (p < 0.001), and gave similar predictions. The hazard of TLN increased by 14% per Gy3, and it was estimated that 64 Gy (at conventional fractionation of 2 Gy daily) would lead to a 5% necrotic rate at 10 years. Not only did the nominal standard dose (NSD) show the lowest value in terms of log likelihood and standardized HR, but its predictions on TLN deviated markedly from clinically observed rates. CONCLUSION: Fractional effect is the most significant factor affecting cerebral necrosis, and overall time has little protective effect. The BED formula, assuming an alpha/beta ratio of 3 Gy, is an appropriate model for predicting late effects on the temporal lobe, and NSD could give seriously misleading predictions.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Fracionamento da Dose de Radiação , Neoplasias Nasofaríngeas/radioterapia , Lesões por Radiação/etiologia , Lobo Temporal/patologia , Lobo Temporal/efeitos da radiação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Encefalopatias/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Necrose , Lesões por Radiação/patologia , Radiobiologia , Fatores de Tempo
8.
Int J Radiat Oncol Biol Phys ; 38(1): 43-52, 1997 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9212003

RESUMO

PURPOSE: To identify factors for maximizing local salvage and minimizing damages by reirradiation for recurrent nasopharyngeal carcinoma. METHODS AND MATERIALS: 654 patients with recurrent nasopharyngeal carcinoma treated by reirradiation during 1976-1992 were retrospectively analyzed. Various fractionation schedules had been used during primary treatment with the total dose ranging from 45.6-70 Gy, fractional dose (at different phases) 1.5-4.2 Gy, and overall time 36-101 days. The gap between the two courses ranged from 0.5-10.6 years. Eighty-two percent of patients were reirradiated with teletherapy, 6% brachytherapy, and 12% with both. For those treated with teletherapy alone, the total dose ranged from 7.5-70 Gy, fractional dose 1.8-5 Gy, and overall time 3-89 days. RESULTS: The 5-year actuarial local salvage and complication-free rates were 23% and 52%, respectively. Multivariate analyses showed that the extensiveness of local recurrence was the most significant factor affecting local salvage, while T-stage of primary tumor also influenced prognosis. Choice of method for reirradiation and fractional effect during both courses affected the risk of late complications. For patients treated by teletherapy alone, the hazard of local failure decreased by 1.7% per Biological Effective Dose (assuming alpha/beta ratio = 10) of the second course, while radiation factors during primary radiotherapy had no significant effect. On the other hand, the risk of late complications was predominantly affected by the primary treatment: the hazard increased by 4.2% per Biological Effective Dose (assuming alpha/beta ratio = 3) of the first course, while the corresponding impact of reirradiation failed to reach statistical significance. Length of the gap between the two courses did not affect the outcome. CONCLUSION: Early detection of local recurrence and adequate total dose by reirradiation are crucial for improving the chance of local salvage. Combination of teletherapy and brachytherapy should be considered whenever feasible and large fractional dose avoided to minimize late complications. Optimization of biological dose during primary treatment is important.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Recidiva Local de Neoplasia/radioterapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Braquiterapia , Césio/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Lesões por Radiação/etiologia , Dosagem Radioterapêutica , Estudos Retrospectivos , Terapia de Salvação , Falha de Tratamento
9.
Hong Kong Med J ; 3(4): 355-361, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11847385

RESUMO

This is a retrospective analysis of 4768 patients with undifferentiated or non-keratinising carcinoma of the nasopharynx who were treated during 1 January 1976 to 31 December 1985. The mean duration of symptoms before diagnosis was 8 months (range, 1-36 months for 95% of patients). A significant association between the duration of symptoms and the presenting stage was observed (P<0.001); 58% and 39% of stage I and stage V patients, respectively, reported as having had symptoms for less than 6 months. Of the later presenters (those having had symptoms for 6 months or longer), 89% were given a full course of radical megavoltage radiotherapy, but 6% were too advanced for any irradiation attempt. Consequently, the 10-year actuarial disease-specific survival was significantly higher among the early presenters: 48% versus 42% (P<0.001). The importance of early detection is emphasised.

10.
Clin Oncol (R Coll Radiol) ; 8(3): 146-54, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8814368

RESUMO

To evaluate the prognostic accuracy of N-staging by Ho's and the UICC/AJCC systems, 5020 patients with undifferentiated or poorly differentiated squamous cell carcinoma of the nasopharynx treated at the Queen Elizabeth Hospital, Hong Kong in the period 1976-1985 were analysed retrospectively. They were initially staged with Ho's system, but detailed records of nodal involvement allowed accurate retrospective restaging with the UICC/ AJCC (1988) system. Staging assessment depended almost entirely on physical examination; only 14% of patients had additional investigations with computed tomography. To evaluate the independent significance of different nodal parameters, T-stage adjusted analyses of the 4730 patients presenting without distant metastases were performed. Both N-staging systems showed a strongly significant overall correlation with distant failures and cancer-specific deaths. A significant trend was also shown for nodal failures in node-positive patients. Ho's system was superior in predicting distant failures, while the UICC/AJCC system was superior for nodal failures. However, even with due adjustment for level, the independent significance of nodal size, laterality and fixity could be demonstrated. After adjustment for UICC/AJCC N-stage, both level and fixity were also significant. Furthermore, when adjusted for all other meaningful parameters, there were no significant differences between ipsilateral and contralateral involvement, upper and mid-level extent, and nodal size < or = 3 cm or > 3- < or = 6 cm. N-staging can be further optimized by a newly proposed system incorporating fixity (movable versus fixed), level (upper-mid versus lower), size (greatest diameter < or = 6 cm versus > 6 cm), and laterality (unilateral versus bilateral) as staging criteria.


Assuntos
Carcinoma de Células Escamosas/patologia , Neoplasias Nasofaríngeas/patologia , Estadiamento de Neoplasias/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/secundário , Criança , Estudos de Avaliação como Assunto , Feminino , Seguimentos , Hong Kong , Humanos , Metástase Linfática/patologia , Metástase Linfática/radioterapia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Neoplasias Nasofaríngeas/radioterapia , Exame Físico , Prognóstico , Modelos de Riscos Proporcionais , Dosagem Radioterapêutica , Análise de Regressão , Estudos Retrospectivos , Taxa de Sobrevida , Tomografia Computadorizada por Raios X , Falha de Tratamento , Resultado do Tratamento
11.
Cancer ; 76(3): 413-22, 1995 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-8625122

RESUMO

BACKGROUND: Lymphoepithelioma-like carcinoma (LELC), best known to occur in the nasopharynx, can arise in a variety of sites, such as the salivary gland, thymus, lung, stomach, and skin. Primary LELC of the lung is very rare, with only limited information in the literature. METHODS: The clinicopathologic features of 11 patients with pulmonary LELC collected from two regional hospitals in Hong Kong are described. RESULTS: The patients, all Chinese, were aged 38 to 73 years (median, 54 years), with equal sex incidence. Two of the 8 patients were smokers. Four presented with coin lesions incidentally discovered on chest X-ray, five with cough and blood-stained sputum, and two with pleural effusion. The tumor formed a discrete (9 patients) or an ill-defined (1 patient) nodule in the lung, or, rarely, showed extensive bilateral pulmonary involvement (1 patient). The major bronchi were not involved except in 1 patient. Three patients had lymph node metastasis at presentation; two of them had bone metastasis, one at presentation and one after 9 months. The tumors had pushing margins, and grew in the form of anastomosing islands and sheets, comprising syncytial-appearing large cells with vesicular nuclei and prominent nucleoli. They were infiltrated by an appreciable number of small lymphocytes and plasma cells. Intratumoral amyloid globules were found in one tumor. In five patients, the tumor showed intraepithelial growth within the small bronchi; this could represent either the in-situ phase of the tumor or pagetoid spread into the bronchial epithelium. The neoplastic cells of all patients harbored Epstein-Barr virus (EBV) as demonstrated by in situ hybridization for EBV-encoded small nuclear RNAs. All eight Asian patients with pulmonary LELC previously reported in the literature similarly have been EBV-positive, whereas the four reported Caucasian patients all have been EBV-negative. CONCLUSION: Lymphoepithelioma-like carcinoma of lung occurring in Asians is an EBV-associated neoplasm; it also appears to occur at a higher frequency in Asians than Caucasians. It usually presents as a solitary subpleural nodule, and there is no strong association with cigarette smoking. Most patients have early stage disease at presentation. From the limited available data, the behavior of LELC of lung is highly variable, ranging from apparent curability by excision (particularly for localized disease) to highly aggressive, extensive disease at presentation.


Assuntos
Carcinoma de Células Escamosas/patologia , Neoplasias Pulmonares/patologia , Adulto , Idoso , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/virologia , Feminino , Herpesvirus Humano 4/isolamento & purificação , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/virologia , Masculino , Pessoa de Meia-Idade , Radiografia
12.
Radiother Oncol ; 36(1): 24-31, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8525022

RESUMO

To study the effect of radiation factors on local control of nasopharyngeal carcinoma, 1008 patients with similarly staged T1N03M0 disease (Ho's classification) were retrospectively analyzed. All patients were treated by megavoltage irradiation alone using the same technique. Four different fractionation schedules had been used sequentially during 1976-1985: with total dose ranging from 45.6 to 60 Gy and fractional dose from 2.5 to 4.2 Gy. The median overall time was 39 days (range = 38-75 days). Both for the whole series and 763 patients with nodal control, total dose was the most important radiation factor. The hazard of local failure decreased by 9% per additional Gy (p < 0.01). Biological equivalents expressed in terms of Biologically Effective Dose or Nominal Standard Dose also showed strong correlation. Fractional dose had no significant impact. The effect of overall treatment time was insignificant for the whole series, but almost reached statistical significance for those with nodal control (p = 0.06). Further study is required for elucidation, as 85% of patients completed treatment within a very narrow range (38-42 days), and the possible hazard is clinically too significant to be ignored.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Radioterapia de Alta Energia , Análise Atuarial , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/secundário , Intervalo Livre de Doença , Feminino , Humanos , Modelos Logísticos , Linfonodos/efeitos da radiação , Metástase Linfática , Masculino , Análise Multivariada , Neoplasias Nasofaríngeas/patologia , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Dosagem Radioterapêutica , Eficiência Biológica Relativa , Estudos Retrospectivos , Fatores de Tempo
14.
Int J Radiat Oncol Biol Phys ; 30(5): 1111-7, 1994 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-7961019

RESUMO

PURPOSE: To study the effect of unperturbed tumor growth on the control of nasopharyngeal carcinoma. METHODS AND MATERIALS: This is a retrospective analysis of 290 patients with T1N0-3M0 disease (Ho's classification) treated by the same technique and dose schedule to the nasopharyngeal region. The median interval from diagnosis to commencement of irradiation was 26 days (range: 8-68 days). Cox proportional hazards analyses were performed to study the independent effect of waiting time on the probability of failure at various sites. Actuarial failure-free survival of patients with delay < 22 days, 22-28 days and > 28 days were also compared to illustrate the clinical observation. RESULTS: Both tests showed that waiting time had no significant impact on local failure: The N-stage stratified hazard ratio was 0.985 per day, and the 10-year local failure-free survival for the three groups was 76%, 80%, and 82%, respectively. A similar result was obtained for nodal control in patients with our scheduled neck irradiation. Although the p value of all tests failed to reach statistical significance, the N-stage stratified hazard ratio for distant failure was 1.020 per day, and the corresponding metastasis-free survival in patients with N2-3 disease was 70%, 65%, and 52%, respectively. For node-negative patients without elective neck irradiation, the hazard ratio was 1.019 per day, with the corresponding regional failure-free rates at 57%, 62%, and 33%, respectively. CONCLUSION: Delay in initiation of treatment to the primary target (within the range observed) did not affect the control rate at irradiated sites, but there was a trend (though statistically insignificant) towards increase in failures at untreated sites that were clinically too serious to be ignored.


Assuntos
Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/radioterapia , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/radioterapia , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Metástase Neoplásica , Estadiamento de Neoplasias , Probabilidade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Tempo , Falha de Tratamento
15.
Cancer ; 74(9): 2414-24, 1994 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-7922994

RESUMO

BACKGROUND: Epstein-Barr virus BZLF-1 replication activator (ZEBRA) is involved in the switch from viral latency to a productive cycle. Previous immunofluorescent study has shown that patients with nasopharyngeal carcinoma (NPC) have elevated immunoglobulin-G (IgG) antibody titres against recombinant ZEBRA protein (ZEBRA/IgG). METHODS: The prognostic role of ZEBRA/IgG was further investigated by enzyme-linked immunosorbent assay (ELISA) in 110 NPC patients under long period of clinical follow-up. RESULTS: Ninety-seven percent (85 of 88) of the patients with NPC had significantly higher ZEBRA/IgG titres (geometrical mean titre, i.e., GMT = 8397) than normal Chinese individuals (GMT = 233 and P < 0.0001). Based on Kaplan-Meier analysis, the actuarial survival in patients with high ZEBRA/IgG titres (25%) after radiotherapy was significantly lower than that of those with low (76%; P = 0.0008) or intermediate titres (62%; P = 0.0036), although the titres taken before treatment did not bear such a relationship. Subdividing the patients into either individual UICC or Ho's stages, those with late-stage disease (UICC Stage 4 and Ho's Stages 3 and 4) and with high ZEBRA/IgG titres also had poorer prognosis than those with disease of the same stages but who had low titres. Poor prognosis in those with high titres could be associated with a high risk of distant metastasis because consistent titre increase was found in the majority of patients who later developed distant metastasis either in the lung or liver. Only a minimal increase was found in patients with recurrence in the cervical lymph nodes. No consistent increase was observed, however, in patients whose disease was in remission or the majority of those with bone metastasis or local recurrence in the nasopharynx. CONCLUSION: The postradiotherapy ZEBRA/IgG titre could be a potentially useful marker for differentiating NPC patients with poor prognosis from those at high risk for the development of distant metastasis to the lung or liver.


Assuntos
Biomarcadores Tumorais/imunologia , Proteínas de Ligação a DNA/imunologia , Infecções por Herpesviridae/imunologia , Herpesvirus Humano 4/imunologia , Imunoglobulina G/imunologia , Neoplasias Nasofaríngeas/virologia , Transativadores/imunologia , Infecções Tumorais por Vírus/imunologia , Proteínas Virais/imunologia , Biomarcadores Tumorais/análise , Proteínas de Ligação a DNA/análise , Ensaio de Imunoadsorção Enzimática , Herpesvirus Humano 4/isolamento & purificação , Humanos , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/secundário , Neoplasias Nasofaríngeas/imunologia , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/radioterapia , Prognóstico , Proteínas Recombinantes/imunologia , Testes Sorológicos , Taxa de Sobrevida , Transativadores/análise , Infecções Tumorais por Vírus/mortalidade , Proteínas Virais/análise
16.
Arch Pathol Lab Med ; 118(10): 994-7, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7944902

RESUMO

The Epstein-Barr virus (EBV)-encoded RNAs in situ localization procedure is a convenient, highly sensitive, and highly specific technique that is applicable to routinely fixed, paraffin-embedded tissue sections; this technique can be used for the study of the association and, hence, the possible causal role of EBV in tumors. This study was performed to elucidate whether EBV plays a role in the pathogenesis of tumors that arise in the salivary glands, since the salivary gland is known to be a reservoir for EBV replication. Cases that were selected included 61 examples of various benign and malignant neoplasms, as well as tumorlike conditions of the major and minor salivary glands. Only the five cases of lymphoepithelial carcinoma (so-called malignant lymphoepithelial lesion) and the single case of metastatic nasopharyngeal undifferentiated carcinoma showed staining with EBV-encoded RNAs, whereas negative findings were found in all of the other cases. In the cases with positive results, all of the neoplastic epithelial cells showed strong nuclear signals, but the lymphoid cells were negative. The consistent association of EBV with lymphoepithelial carcinoma of the salivary gland suggests that the virus probably plays a causal role in this tumor, at least in the Asian population, whereas there is no evidence for a causal role of EBV in other primary tumors of the salivary gland.


Assuntos
Carcinoma de Células Escamosas/virologia , Infecções por Herpesviridae/patologia , Herpesvirus Humano 4/isolamento & purificação , Neoplasias das Glândulas Salivares/patologia , Neoplasias das Glândulas Salivares/virologia , Infecções Tumorais por Vírus/patologia , Adulto , Idoso , Carcinoma de Células Escamosas/patologia , Feminino , Herpesvirus Humano 4/genética , Humanos , Hibridização In Situ , Masculino , Pessoa de Meia-Idade , RNA Viral/análise
17.
Am J Surg Pathol ; 18(9): 938-46, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8067515

RESUMO

Recent studies have suggested a probable etiologic association between Epstein-Barr virus (EBV) and nasal lymphomas, irrespective of geographic location. This study was performed to investigate the strength of association of EBV with non-Hodgkin's lymphomas of the upper aerodigestive tract, based on a large series of cases that have been thoroughly immunophenotyped on frozen tissues. A sensitive in situ hybridization technique was used to detect EBV encoded RNA (EBER) in paraffin sections. Among 30 cases of nasal/nasopharyngeal T-cell lymphoma, 25 (83.3%) were EBER-positive. In the positive cases, most of the neoplastic cells showed strong nuclear signals. Further analysis of this group of tumors showed that all 21 cases (100%) with a CD56+ CD3-phenotype were EBER positive, whereas four of nine cases (44.4%) with a CD56-negative immunophenotype were positive. Only one of 10 cases (10%) of nasal/nasopharyngeal B-cell lymphoma was EBER positive; the positive case was a diffuse mixed-cell lymphoma and could not be distinguished morphologically from the negative cases. Among the 21 cases of lymphoma of the tonsils and back of the tongue (20 B-lineage and one T-lineage), none was EBER positive. In the normal mucosa of the nose/nasopharynx or tonsil (20 cases studied), only very rare EBER-positive small lymphocytes were found in two cases. The almost exclusive detection of EBER in nasal/nasopharyngeal T-cell neoplasms among the lymphomas of the upper aerodigestive tract suggests that EBV probably plays an etiologic role in the pathogenesis of this group of tumors and is not simply a passenger virus, and neither is this merely a site-dependent phenomenon in view of the weak association with nasal/nasopharyngeal B-cell lymphoma.


Assuntos
Herpesvirus Humano 4/isolamento & purificação , Linfoma/microbiologia , Neoplasias Nasofaríngeas/microbiologia , Neoplasias Nasais/microbiologia , RNA Viral/análise , Proteínas Ribossômicas , Neoplasias Tonsilares/microbiologia , Herpesvirus Humano 4/genética , Humanos , Imuno-Histoquímica , Hibridização In Situ , Linfoma/patologia , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasais/patologia , Proteínas de Ligação a RNA/genética , Neoplasias Tonsilares/patologia
18.
Hum Pathol ; 25(8): 758-65, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7520016

RESUMO

We recently reported a group of non-nasal/nasopharyngeal hematolymphoid malignancies expressing the natural killer cell marker CD56, characterized by frequent extranodal localization, angiocentricity, and aggressive clinical course (HUM PATHOL 23:798-804, 1992). Because we have shown a very strong association of Epstein-Barr virus (EBV) with CD56-positive T-cell lymphomas of the nose nasopharynx, we asked whether a similar association also occurs with the non-nasal CD56-positive T-cell lymphomas. In situ localization of EBV encoded RNA (EBER) was performed on paraffin sections of 15 such cases, including the nine previously reported cases and six new cases (three showing prominent hepatosplenic involvement and three showing involvement of one or more extranodal sites, such as the parotid gland, tonsils, gastrointestinal tract, skeletal muscle, and testis). A case was considered positive when the majority of the tumor cells showed nuclear signal. Ten cases showed EBER positivity, and all but one of them were negative for CD3 and other T-cell markers, except CD2. Only one of four cases showing a CD3-positive phenotype was EBER positive. Of the remaining two CD3-negative EBER-negative cases, one showed a histiocytic phenotype and the other was positive for multiple T-cell markers. Among 15 cases of CD56-negative non-nasal peripheral T-cell lymphoma studied for comparison, six were CD3-negative, among which three showed EBER positivity. All nine CD3-positive cases were EBER negative. Five cases (three CD3 positive and two CD3 negative) showed rare isolated (< 1%) EBER-positive tumor cells. We conclude that among non-nasal T-cell lymphomas, EBV is strongly correlated with CD56 positivity (66.7% v 20%), and the positive cases almost always show an immunophenotype identical to that commonly observed in nasal lymphomas (CD2 positive, CD3 negative, and CD56 positive). Thus, EBV may play an etiologic role in these CD56-positive lymphomas. There is also a correlation between EBER positivity and CD3 negativity, irrespective of the CD56 status. The presence of isolated EBER-positive cells in CD56-negative T-cell lymphomas, occurring at a frequency similar to that reported in the European population, probably represents secondary infection of tumor cells.


Assuntos
Antígenos CD/análise , Antígenos de Diferenciação de Linfócitos T/análise , Herpesvirus Humano 4/isolamento & purificação , Linfoma de Células T/microbiologia , Neoplasias Nasofaríngeas/microbiologia , RNA Viral/análise , Adulto , Idoso , Antígeno CD56 , Criança , Feminino , Herpesvirus Humano 4/genética , Humanos , Imunofenotipagem , Hibridização In Situ , Linfoma de Células T/imunologia , Linfoma de Células T/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/imunologia , Neoplasias Nasofaríngeas/patologia
19.
Int J Radiat Oncol Biol Phys ; 26(5): 773-82, 1993 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-8344845

RESUMO

PURPOSE: To study the value of re-irradiation, the overall survival and pattern of failures for patients with nasopharyngeal recurrence. METHODS AND MATERIALS: All the 891 patients with local recurrence following radiotherapy for nasopharyngeal carcinoma during 1976-1981 were retrospectively analyzed. Only 70% of them had local failure alone at the time of detection, and the T-stage distribution (by Ho's system) was 31% rT1, 16% rT2, 51% rT3, and 1% rT?. Seven hundred and six (79%) patients had been re-irradiated with various techniques and doses. Among those who failed, 50 had further irradiation. RESULTS: The overall 5- and 10-year actuarial cancer-specific survival rates were 14% and 9%, respectively. Patients with rT3 disease had the worst prognosis. Successful local salvage was achieved in 32% of those re-irradiated (26% of the whole series). The highest control rate was achieved by those treated with external radiotherapy to 60 Gy (equivalent) or above. Only 8/50 patients responded to the third course of radiotherapy. The cumulative incidence of late post-re-irradiation sequelae was 24%, and the treatment mortality rate 1.8%. Besides local failure, 54% had regional relapse and/or distant metastasis. Thus, only 16% of recurrent patients were totally disease-free at final assessment. CONCLUSION: The overall prognosis for patients with nasopharyngeal recurrence was grave. High dose re-irradiation could achieve successful local salvage in a substantial number of patients with early recurrence, but late complications did occur. Furthermore, high incidence of failure at other sites was observed.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/radioterapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Braquiterapia , Carcinoma de Células Escamosas/epidemiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/epidemiologia , Recidiva Local de Neoplasia/epidemiologia , Estudos Retrospectivos , Análise de Sobrevida , Taxa de Sobrevida
20.
Br J Radiol ; 66(786): 528-36, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8330138

RESUMO

This is a retrospective analysis of the long-term local control in 4128 patients with non-disseminated nasopharyngeal carcinoma treated solely by megavoltage irradiation during the years 1976-1985. The T-stage distribution according to Ho's classification was T1 37%, T2 14% and T3 49%. Different fractionation schedules had been employed at different periods, and the median dose to the primary target was equivalent to 65 Gy by time dose fractionation calculation. In 8% (344) of patients the tumour failed to regress completely after the basic course, but 89% (148/167) of those suitable for salvage with additional irradiation eventually attained complete local remission. The cumulative incidence of local failure was 24% (5% persistence, 19% recurrence). The 10-year actuarial local failure-free survival was 67%. While patients with T2 and T3a tumours achieved local control comparable to T1, those with T3c-d had the poorest control (with highest incidence of persistence and advanced recurrence). T-stage adjusted analyses suggested a significant trend of dose-response: the odds ratios for local failure were 1.16 and 1.86, respectively, when patients given 60-63 Gy and 55-59 Gy were compared with those given 64 Gy or above (p value = 0.0018). Patients treated during 1981-1985 achieved higher local failure-free survival than those treated during 1976-1980 (75% versus 70% at 5 years, p value = 0.0013). The possible attributes are studied, and ways for future optimization of treatment discussed.


Assuntos
Neoplasias Nasofaríngeas/radioterapia , Radioterapia de Alta Energia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Relação Dose-Resposta à Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/mortalidade , Recidiva Local de Neoplasia , Estudos Retrospectivos
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