Tumor types: There has been a long-lasting debate about classification of canine mammary tumors. According to the World Health Organization (WHO), canine mammary tumors are histologically classified into four categories: malignant tumors, benign tumors, unclassified tumors, and mammary hyperplasias/dysplasias.
Gandy dancer is a slang term used for early railroad workers who laid and maintained railroad tracks in the years before the work was done by machines.
Michael Quinion identified the first known (printed) use of the term gandy dancer as 1918, but with so little understanding of the origin of the term it is impossible to know when it came into being.