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1.
Int J Radiat Oncol Biol Phys ; 68(2): 465-71, 2007 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-17418962

RESUMO

PURPOSE: To investigate a potential link between telomere length, chromosomal instability, and the advent of a second cancer (SC) in patients with Hodgkin's lymphoma (HL), who are known to be at risk for SCs. This study was premised on the finding that telomere dysfunction and DNA repair pathways were related to many pathologic conditions. METHODS AND MATERIALS: Three cohorts of patients with HL were studied: 73 who were prospectively followed >5 years after diagnosis (prospective HL cohort), 28 who developed a SC (SC HL cohort), and 18 long-term survivors with no evidence of disease or complication since their initial treatment (NED HL cohort). Telomere length was analyzed by a telomeric restriction fragment assay in peripheral blood lymphocytes. Thirty healthy donors and 70 patients with a newly diagnosed solid tumor were the control population. RESULTS: Compared with controls, patients from the prospective HL cohort, before any treatment, showed age-independent shorter telomeres (mean, 8.3 vs. 11.7 kb in healthy donors; <6 kb in 18% in HL patients), increased spontaneous chromosomal abnormalities, and increased in vitro radiation sensitivity (p < 10(-4) each). After treatment, telomere shortening was associated with cytogenetic profiles characterized by the persistence of complex chromosomal rearrangement and clonal aberrations. Moreover, the two cases of SC in the prospective HL patients had short telomeres and CCR initially. In addition, the SC HL cohort was characterized by markedly short telomeres (6.6 vs. 9.7 kb in the NED HL cohort), the presence of complex chromosome rearrangements, and increased in vitro radiation sensitivity. CONCLUSIONS: An intimate relationship between pre-treatment telomere shortening, chromosomal instability, radiation sensitivity and occurrence of SC was found in HL patients.


Assuntos
Instabilidade Cromossômica/genética , Doença de Hodgkin/genética , Linfócitos , Segunda Neoplasia Primária/etiologia , Telômero/patologia , Adulto , Idoso , Neoplasias da Mama/genética , Carcinoma Basocelular/genética , Estudos de Coortes , Reparo do DNA , Feminino , Seguimentos , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/radioterapia , Humanos , Linfócitos/patologia , Linfócitos/efeitos da radiação , Masculino , Pessoa de Meia-Idade , Segunda Neoplasia Primária/genética , Estudos Prospectivos , Tolerância a Radiação , Neoplasias Cutâneas/genética , Sobreviventes
2.
Int J Radiat Oncol Biol Phys ; 52(5): 1186-95, 2002 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11955729

RESUMO

PURPOSE: Stable chromosomal aberrations (SCAs) have been found in circulating lymphocytes from patients treated for breast carcinoma. Therefore, we tried to define their incidence in such patients, to determine an in vitro dose-effect relationship, and to correlate these data with clinical parameters. METHODS AND MATERIALS: This prospective study included 25 patients who, after surgery, underwent either radiotherapy (RT) alone (n = 15) or RT combined with chemotherapy (n = 10). SCAs were scored using the fluorescent in situ hybridization technique before RT and 4 and 12 months after RT. Dose-effect curves were established by in vitro irradiation of blood samples with 2 and 4 Gy, before and after treatment. RESULTS: In all patients, the rate of SCAs increased significantly after external irradiation. No significant decrease in SCAs was observed during the first year after RT. RT and chemotherapy had no effect on the lymphocyte in vitro dose-effect relationship. No relationship was found in the distribution of patients between the yield of SCAs scored after external irradiation and after in vitro irradiation. SCAs after RT or in vitro irradiation did not correlate with family history of breast carcinoma or acute toxicity of treatment. More significantly, the yield of SCA after external irradiation was strongly related to the irradiation of the internal mammary chain and the supraclavicular lymph node area, suggesting that the volume of irradiated blood vessels was an essential parameter in determining the rate of SCAs. CONCLUSION: A high and stable yield of SCAs persisted at least 1 year after external irradiation. The nature of the volume irradiated containing large blood vessels was the major determinant of the observed biologic dose.


Assuntos
Neoplasias da Mama/radioterapia , Aberrações Cromossômicas , Linfócitos/efeitos da radiação , Adulto , Idoso , Idoso de 80 Anos ou mais , Mama/efeitos da radiação , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Terapia Combinada , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Feminino , Humanos , Hibridização in Situ Fluorescente , Linfonodos/efeitos da radiação , Linfócitos/efeitos dos fármacos , Pessoa de Meia-Idade , Estudos Prospectivos
3.
Eur J Nucl Med Mol Imaging ; 30(10): 1413-7, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12955483

RESUMO

The risk of development of cancer, and more specifically acute leukaemia, after use of phosphorus-32 in patients with polycythaemia vera has been recognised for approximately 40 years. As a consequence of this risk, the indications for, and contraindications to, 32P are unclear in the physician's mind. This paper aims to clarify the problem. The relation between polycythaemia vera and leukaemia is explored and the question of whether chemotherapy represents an alternative to 32P is discussed. From the results obtained to date, two clear conclusions can be drawn: First, whatever the age of the patient, phlebotomy must be used to avoid the menace of vascular complications before the institution of basic treatment, but it cannot be used as the sole form of treatment. Second, 32P treatment retains an important role at least when chemotherapy fails and in elderly patients (>70 years).


Assuntos
Leucemia/epidemiologia , Radioisótopos de Fósforo/uso terapêutico , Policitemia Vera/tratamento farmacológico , Policitemia Vera/epidemiologia , Medição de Risco/métodos , Distribuição por Idade , Idoso , Comorbidade , Feminino , Humanos , Incidência , Masculino , Neoplasias/epidemiologia , Padrões de Prática Médica , Fatores de Risco , Distribuição por Sexo , Taxa de Sobrevida
4.
Pediatr Hematol Oncol ; 20(8): 651-6, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14578036

RESUMO

Hoyeraal-Hreidarsson syndrome (HHS) is a severe infantile variant of X-linked dyskeratosis congenita (DC). The authors report evidence of increased in vitro sensitivity to radiation and alkylating agent in circulating lymphocytes and fibroblasts obtained from a 7-year-old boy with HHS. A major telomere shortening was also found (3 kb) as compared to healthy donors (10 kb). The standard treatments, chemotherapy regimens, and radiation therapy were not possible. The data suggest that conditioning regimens including TBI should not be used when a bone marrow transplantation procedure is planned in these patients.


Assuntos
Anormalidades Múltiplas/genética , Alquilantes/farmacologia , Fibroblastos/efeitos da radiação , Linfócitos/efeitos da radiação , Anormalidades Múltiplas/tratamento farmacológico , Anormalidades Múltiplas/radioterapia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Criança , Cromossomos Humanos X , Fibroblastos/efeitos dos fármacos , Ligação Genética , Humanos , Linfócitos/efeitos dos fármacos , Masculino , Tolerância a Radiação , Síndrome
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