Mammary tumours in entire bitches- spay or not?

RE: Mammary tumours in entire bitches- spay or not?

Rob Loxley — Thu, 24 Oct 2019 17:07:30 GMT

I think removal of pyometra risk is a good enough reason to spay. I also advise clients there is some evidence that spaying even in older dogs can reduce down the risk of further mammary tumors (the old dogma about no benefit if dog older than 2 years old is older than me...) and frankly there's not a lot else that might work better to prevent further mammary problems.

RE: Mammary tumours in entire bitches- spay or not?

Thomas Johnson — Thu, 24 Oct 2019 12:55:31 GMT

[quote user="vetbl.locum"]

Thanks for replies

Even ly divided so far but I am inclined to favour the new kit new gloves approach

Also I want to ensure good lump margins and not have to worry about fitting in spay wound

[/quote]

If I were doing the spay after the mammary lump I would definitely change kit and gloves, but if doing the spay first, I don't see the need. Anything going into the abdomen (gloved hand, instruments) or coming out, is going to be in contact with the edges of the skin incision so I'm not sure what difference it would make changing kit and gloves?

RE: Mammary tumours in entire bitches- spay or not?

vetbl.locum — Thu, 24 Oct 2019 12:08:55 GMT

Thanks for replies

Even ly divided so far but I am inclined to favour the new kit new gloves approach

Also I want to ensure good lump margins and not have to worry about fitting in spay wound

Does amount of surgical 'insult' have any effect on lump spread?

Rgds

RE: Mammary tumours in entire bitches- spay or not?

Jill Butterworth — Thu, 24 Oct 2019 11:04:54 GMT

[quote user="vetbl.locum"]

For those doing spay at time of lump removal:

Do you use a separate surgical pack for each procedure ? And or re glove ?

[/quote]

Absolutely! It's possible to seed the mammary tumour into the peritoneal cavity, my preference would always be to do on a different occasion. I used to use a different kit/gloves for closing up any tumour with a reasonable chance of malignancy.

It's interesting/counterintuitive to note that although the research indicates that mammary masses are not hormonally induced in bitches, it is nevertheless rare to see them in spayed bitches (whether or not it was done before the first season, as we were taught).

RE: Mammary tumours in entire bitches- spay or not?

Thomas Johnson — Thu, 24 Oct 2019 10:59:21 GMT

[quote user="vetbl.locum"]

For those doing spay at time of lump removal:

Do you use a separate surgical pack for each procedure ? And or re glove ?

[/quote]

I do the spay first. If the mammary masses aren't lateral to where I would normally make my spay incision then spay as normal, and use the same kit and gloves to do the mammary mass removal. If it's all going to be done through one incision then I'll make the incision for the part of the mammary mass removal that will allow me to do the spay first, making doubly sure I'm happy with the margins I'm taking, do the spay, close the linea alba, and then finish making the skin incision and do the mammary mass removal, again no change of kit and gloves.

RE: Mammary tumours in entire bitches- spay or not?

vetbl.locum — Thu, 24 Oct 2019 09:32:41 GMT

For those doing spay at time of lump removal:

Do you use a separate surgical pack for each procedure ? And or re glove ?

Rgds

RE: Mammary tumours in entire bitches- spay or not?

Julie Innes — Thu, 24 Oct 2019 09:01:43 GMT

Like others, no clue on current thinking, but was taught at uni (in the distant past!) to spay. I'll usually discuss it with owners, stress that it doesn't absolutely prevent recurrence, and tend to really only do it if small masses, not full on mammary strip.

RE: Mammary tumours in entire bitches- spay or not?

Julian Earl — Wed, 23 Oct 2019 20:53:59 GMT

Thanks Thomas. I only did it once, for the obvious reason and I cannot remember if it would have been feasible through a single skin incision. It was in my first couple of years after qualification so a long time ago! But the outcome was bad enough to convince me never to try it again, certainly for a mammary tumour of significant size! I think that I removed small nodules from glands at the same time but cannot recall excising a whole gland or several at the same time as speying after that one occasion. I had tried to learn from what I considered a mistake! Hence me passing on my experience here.

RE: Mammary tumours in entire bitches- spay or not?

Thomas Johnson — Wed, 23 Oct 2019 14:41:34 GMT

[quote user="Julian Earl"]

But having a midline incision and a parallel one to the side for the tumour can seriously impede healing and a slough of skin due to ischaemia can result. I found this out the hard way! So personally I would never[again] do them together. Once was enough! The priority is probably the tumour and Spey on another occasion.

[/quote]

When I've done it I have never needed to have parallel wounds to suture. The margin of the incision for the mammary tumour removal is normally close enough to the midline to see the linea alba, and if not you can dissect under the skin to reveal it.

I will normally discuss spaying at the same time as mammary tumour removal, but make owners aware that it isn't likely to reduce the chance of further tumours. I think prevention of pyometra is a good enough reason to do it though.

RE: Mammary tumours in entire bitches- spay or not?

Julian Earl — Wed, 23 Oct 2019 09:54:01 GMT

RE: Mammary tumours in entire bitches- spay or not?

Iain Richards — Wed, 23 Oct 2019 09:50:44 GMT

Spay. But only to help distinguish future tumours from hyperplasia.

Tamoxifen - works on specific receptors that most dogs don't have

RE: Mammary tumours in entire bitches- spay or not?

KathW — Tue, 22 Oct 2019 22:41:33 GMT

If it’s one or two small masses I will recommend spaying at the same time. As stated by others, in older bitches there are minimal protective effects against the patient developing future mammary masses ( I don’t have the figures to hand). I always warn owners about this. It will stop a future pyometra and it’s one anaesthetic so less cost to the owner overall.

If there are multiple larger masses and the surgery is close to the site of my proposed spay incision or if the patient isn’t stable under GA I will usually not spay at the same time as removing the mammary masses.

RE: Mammary tumours in entire bitches- spay or not?

Michael Woodhouse — Tue, 22 Oct 2019 22:29:10 GMT

There are some papers showing no protective effect and some show a small effect:

https://www.ncbi.nlm.nih.gov/pubmed/23701181

My view would be to recommend spay at same time as it MIGHT help prevent further tumours, is a single anaesthetic and prevents pyo etc.

RE: Mammary tumours in entire bitches- spay or not?

janine redman — Tue, 22 Oct 2019 22:00:50 GMT

There was a paper from one of the referral centres about a medical treatment to reduce recurrence of mammary tumours ? Would be about a year ago?

RE: Mammary tumours in entire bitches- spay or not?

Beats — Tue, 22 Oct 2019 21:59:47 GMT

[quote user="Sarah Keir"]if hormonally related but I believe most are not in dogs, which is why the human breast cancer drugs like tamoxifen are of no use.[/quote]

I was taught at uni (OK so quite a while back... and have never checked up since) that tamoxifen was of no use in dogs re mammary masses as a simple result of basic pharmacology as it behaved as a partial agonist rather than antagonist in bitches (I think).

RE: Mammary tumours in entire bitches- spay or not?

Sarah Keir — Tue, 22 Oct 2019 21:54:18 GMT

Hi Yantha, no such thing as a basic question. The only fool is the one who doesn't ask the question and assumes they know the answers!

Like you, I used to OHV at the time of mammary mass removal but it is too late to stop future masses as we usually see these in bitches 5 years plus. Perhaps a small reduction in risk if hormonally related but I believe most are not in dogs, which is why the human breast cancer drugs like tamoxifen are of no use. However, it is a good a time as any to get the owner to agree to neutering even if a little white lie like reducing chance of future masses is needed!

RE: Mammary tumours in entire bitches- spay or not?

Beats — Tue, 22 Oct 2019 21:46:51 GMT

I generally spay (sometimes just ovaries), but don't always (probably less likely to if major mammary mass resection and more likely to if fairly small nodule(s); if masses have been noted to increase in size with season or has irregular cycling I would spay).

I have no idea what the current thinking is though.