Retrospective review and systematic study of mammary tumors in dogs and characteristics of the extracellular matrix

Abstract

The aim of the present study was to perform a retrospective review, from 1932 to 1999, in order to establish the number of cases of mammary tumors in dogs in the records at the Pathology Department of Faculdade de Medicina Veterinária - USP, as well as the presence of desmoplasia and cartilaginous and bone metaplasia in 578 of these tumors. Among the 537 malignant tumors, 13.05% were simple tubular adenocarcinomas, 3.91% were complex tubular adenocarcinomas, 7.26% simple papillary adenocarcinomas, 4.28% complex papillary adenocarcinomas , 23.27% simple papillary cystadenocarcinomas ,8.37% complex papillary cystadenocarcinomas,16.38% simple solid adenocarcinomas ,6.70% complex solid adenocarcinomas, 2.04% simple spindle cell carcinomas, 1.11% simple spindle cell carcinomas ,2.79% mucinous carcinomas ,8.19% anaplastic carcinomas ,0.93% squamous carcinomas, 1.30% fibrosarcomas,.0.18% chondrosarcoma, 0.18% osteosarcoma and among the 41 benign tumors ,51.21% were adenoma, 12.19% papillary cystadenoma,7.31% papilloma, 4.87% cystic fibroadenoma and 24.39% were fibroadenoma. Both desmoplasia and metaplasia were frequent findings in benign and malignant neoplasms, but they were more frequent among complex tubular adenocarcinomas: 38% presented desmoplasia, 57% cartilaginous metaplasia and 28% bone metaplasia. Among the benign neoplasms, adenoma presented the more frequency: 14 % presented desmoplasia, 29% cartilaginous metaplasia and 24% bone metaplasia. Results of this study emphasize the complexity of the inter-relationship between the macromolecules in the extracellular matrix and tumoral cells.