[Tumors caused by methylcholanthrene and lapachol. Follow-up of development with cytology]

This present work was carried out in order to study the effect of Lapachol (LAP) administrated to rats simultaneously with a chemical carcinogen 20-Methylcholanthrene (MCA). Animals were divided in 4 groups: A-Group treated with 80 mg of MCA I(n = 11 rats), B-Group treated with 80 mg of MCA+LAP 100 mg/kg weight/day, (n = 15 rats), C-Group treated with LAP 100 mg/kg weight/day (n = 12 rats), D-Group control-no treatment (n = 13 rats). Cytological studies as well as cytochemical techniques allowed the recognition of benign and malignant conditions at the time of the tumor appearance. Histopathological evaluation posteriorly confirmed the development of tumors in 53% of the animals in group B. Morphologically consistent with poorly differentiated adenocarcinomas of the salivary glands and fibroadenomas of the breast in 18.2% (2/11) of the rats in group A. Besides the presence of one or several supra-hepatic nodules in vecinity of the suspensory ligament corresponding to nodular hyperplasia were observed in 33% (4/12) of group C and in 13.3% (12/15) of group B. No nodules were observed in groups A and D. Tubular dilatation of kidneys were noted in 60% (9/15) and 83.3/ (10/12) of the rats in group E and C respectively. From the original salivary gland tumor a series of transplantables tumors were developed and followed by cytological evaluations. The importance of the cytological and histopathological diagnosis for the pharmacological effects studies of certain drugs like Lapachol that are widely used as antitumoral agents without exact knowledge of the adverse effects is emphasized.