RESUMO
Squamous cell carcinoma was induced in male 6 to 8-week old NMRI-mice by application of 9,10-dimethyl-1,2-benzanthracene on the skin. 15 weeks later macroscopically visible skin tumors are developed. Then organ distribution and tumor accumulation of 57Co-Bleomycin (spec. activity 1 mCi/3.3 mg) were studied 1 to 48 hours after injection. In squamous cell carcinoma a high uptake of this tumor-seeking agent can be demonstrated (n = 46). After radiotherapy (100 kV; 1.7 mm Al-filter; 18.8 Gy) (n = 26), however, a significantly reduced uptake of 57Co-Bleomycin in tumor tissue is observed. Possible consequences from these animal studies for tumor scintigraphy with this radiopharmaceutical in man are discussed.
Assuntos
Bleomicina/metabolismo , Carcinoma de Células Escamosas/metabolismo , 9,10-Dimetil-1,2-benzantraceno , Animais , Carcinoma de Células Escamosas/induzido quimicamente , Carcinoma de Células Escamosas/radioterapia , Radioisótopos de Cobalto , Masculino , Camundongos , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/radioterapiaRESUMO
Organ distribution and tumor uptake of 57Co-bleomycin (BLM) were examined in NMRI mice without tumor and with chemically (DMBA-) induced squamous cell carcinoma. In these tumors high accumulation of 57Co-BLM was recorded shortly after injection of 57Co-BLM and low uptake 24--48 h after application. Two groups of tumor-bearing mice received unlabeled bleomycin as a cytostatic in two different doses. Uptake of 57Co-bleomycin was reduced. The study suggests that in patients currently or previously under chemotherapy, 57Co-bleomycin tumor scintigraphy may lead to false negative results.