Has anyone any experience of a mammary tumour in their male dog? I'm running ahead of myself after finding a lump on Xylo's chest. He's 7 1/2, neutered a couple of years ago after siring three litters - enough of a contribution to our small gene pool. The lump was tiny a couple of days ago and has about doubled now, growing too fast to be a fatty lump I think. I'm going to get the vet to do a fine needle aspiration to see what it is but I'd like to have my head around options first.

I always said after having a borzoi bitch that had a full mammary strip that I would never do that to a dog again, and in fact the next girl to have mammary tumours I just left them and she lived longer than the one who had the strip and had a better quality of life. But, is it the same op for a boy? Can they just have the lump removed? Anyone any experience?

Is the lump on or near a nipple? Breast cancer in male dogs is extremely rare & the biopsy will be the first step as there is no outward difference between benign & cancerous tumours.

> Is the lump on or near a nipple?

Yes, that's why I titled it mammary tumour

> biopsy will be the first step

I know this, that's why I'm asking for the FNA, and yes I know it's extremely rare, that's why I'm asking on here for experiences. I like to be as prepared as possible for all scenarios.

I hope its something easy .totally get the all scenarios ive researched so many in the last couple of weeks . Somehow it helps to know what I might be dealing with

There is a line of research the lead to a suggestion that mammary cancer is linked to the female sex hormones, however in case studies of male dogs with mammary cancer, Immunohistochemical analysis did not support this theory.

I would suggested doing a biopsy on his testes for leydig cell adenoma, however as he has already been castrated this is not possible.

Hopefully it will be benign

> Somehow it helps to know what I might be dealing with

Exactly, doesn't alter the outcome, but it is good to be prepared.