Efeitos da terapia de curto prazo com tamoxifeno no índice mitótico do epitélio do carcinoma de mama
Arquivos
Data
2005
Autores
Ferreira, Rogerio Bizinoto 
Orientadores
Gebrim, Luiz Henrique
Tipo
Dissertação de mestrado
Título da Revista
ISSN da Revista
Título de Volume
Resumo
Introdução: O tamoxifeno é a mais importante droga utilizada na hormonioterapia do carcinoma de mama. Parece atuar como citostático e pouco se sabe a respeito da proliferação celular após curta exposição ao fármaco. Objetivo: Avaliar o efeito da terapia em curto prazo com tamoxifeno na proliferação celular do epitélio do carcinoma de mama, medida pelo índice mitótico. Pacientes e Métodos: Estudo prospectivo, em 20 pacientes com carcinoma invasivo de mama, com receptores positivos de estradiol e/ou de progesterona. Foi realizada, em todas as pacientes, biópsia incisional diagnóstica. Em seguida, nos dois dias que antecederam a cirurgia
(mastectomia ou quadrantectomia), foram administradas 20 mg/dia de tamoxifeno. Colheu-se outro fragmento do tumor. O material foi fixado em formol tamponado a 10% e corado pela hematoxilina-eosina (HE) para contagem do índice mitótico. Para o estudo quantitativo foram utilizadas fotos digitalizadas em microcomputador em HE (400X), em sistema Windows 98, pelo programa Image-lab 2000®. Os resultados foram comparados pelo teste não paramétrico de Wilcoxon. Resultados: Após dois dias de tratamento com tamoxifeno houve redução na proliferação celular de 16 dos 20 tumores. O número médio de mitoses foi 11 no Grupo 1 (pré-tratamento) e 7,15 no Grupo 2 (pós-tratamento). A análise estatística revelou significância (p<0,001).
Conclusão: O tamoxifeno administrado precocemente e por curto período de tempo (2 dias) promoveu diminuição significante no número de mitoses no epitélio de pacientes com carcinoma de mama. A precoce redução do índice mitótico pode ser um marcador de resposta à terapêutica hormonal primária nas pacientes com carcinoma de mama receptor positivo.
Introduction: Tamoxifen is the most important drug in hormone therapy for breast cancer. It seems to have a cytostatic action and very little is known about cell proliferation after short-term exposure to tamoxifen. Objective: assessing the effect of short-term therapy with tamoxifen on cell proliferation in breast cancer, as measured by the mitotic index. Patients and Methods: prospective study including 20 patients with invasive breast carcinoma, and positive receptors for estradiol and/or progesterone. An incisional biopsy for diagnostic purposes was performed in all the patients. Then, on the 2 days that preceded surgery (mastectomy or quadrantectomy), the patients were given 20 mg/day of tamoxifen. Another tumor fragment was then harvested. The material was fixed in buffered formaldehyde at 10% and stained with hematoxylin and eosin (HE) to determine the mitotic index. A quantitative study was done on the basis of digital photographs. The hardware and software used were a HE (400X) computer, running Windows 98, and Image-lab 2000®. The results were then compared using the non-parametric Wilcoxon test.Results After 2 days of treatment with tamoxifen, cell proliferation decreased in 16 of the 20 tumors. The mean for the mitotic index was 11 in group 1 (pre-treatment) and 7.15 in group 2 (posttreatment). Statistical analysis proved to be significant (p<0.001). Conclusion: This early reduction in the mitotic index can serve as a response marker for primary hormonal therapy in patients with receptor-positive breast cancer.
Introduction: Tamoxifen is the most important drug in hormone therapy for breast cancer. It seems to have a cytostatic action and very little is known about cell proliferation after short-term exposure to tamoxifen. Objective: assessing the effect of short-term therapy with tamoxifen on cell proliferation in breast cancer, as measured by the mitotic index. Patients and Methods: prospective study including 20 patients with invasive breast carcinoma, and positive receptors for estradiol and/or progesterone. An incisional biopsy for diagnostic purposes was performed in all the patients. Then, on the 2 days that preceded surgery (mastectomy or quadrantectomy), the patients were given 20 mg/day of tamoxifen. Another tumor fragment was then harvested. The material was fixed in buffered formaldehyde at 10% and stained with hematoxylin and eosin (HE) to determine the mitotic index. A quantitative study was done on the basis of digital photographs. The hardware and software used were a HE (400X) computer, running Windows 98, and Image-lab 2000®. The results were then compared using the non-parametric Wilcoxon test.Results After 2 days of treatment with tamoxifen, cell proliferation decreased in 16 of the 20 tumors. The mean for the mitotic index was 11 in group 1 (pre-treatment) and 7.15 in group 2 (posttreatment). Statistical analysis proved to be significant (p<0.001). Conclusion: This early reduction in the mitotic index can serve as a response marker for primary hormonal therapy in patients with receptor-positive breast cancer.
Descrição
Citação
FERREIRA, Rogerio Bizinoto. Efeitos da terapia de curto prazo com tamoxifeno no índice mitótico do epitélio do carcinoma de mama. 2005. 45 p. Dissertação (Mestrado em Ciências) - Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, 2005.