Mast cells as prognostic indicator in spontaneous canine mammary carcinomas

Tumour micro-environment is essential to nourish the cancer stem cells (CSC) which are said to be the major cause to initiate recurrence/ metastasis. Though there are many players, mast cells are said to play a key role in tumour metastasis. A cohort of twenty canine mammary carcinomas (CMC) was analysed for the presence of intra-tumoral and peri-tumoral mast cells, corelating it with the progression of the disease and exploring the possibility of finding a prognostic indicator. The mast cell density in the recurrent and non-recurrent CMC cases was examined with toluidine-blue staining. It could be appreciated that there is a significant difference between the intra-tumoral mast cell count/density in malignant recurrent and non-recurrent carcinomas. However, such a difference could not be appreciated with the peri-tumoral tissues in both groups. The malignant recurrent carcinomas had less than 10 mast cells/ hpf, on an average from ten different fields, in the intra-tumoral tissues. Survival analysis carried out revealed that the CMC cases with less than 10 mast cells / hpf had a mean survival time of 24 months. This is the first report where the mast cells were studied for prognostic implications in CMC cases of Kerala. The potential role of these cells in the tumour micro-environment needs further investigation and may open avenues that lead to the identification of anti-oncogenic targets.