Skin disorder

[CaseyGirl]

Has anyone ever seen a BC develop lumps under the skin that don't appear to be dangerous, but are persistent? My dog now has four that are clustered and have grown pretty quickly. My vet says they aren't malignant, but aren't like anything she's ever seen either. They apparently are consistent with what would happen if the dog reacted sensitively to an injection, but they are in a location where there's never been an injection. I've had other breeds that developed "fatty tumors," but this apparently is different. My previous borders didn't have them. Thanks for any info.

[AK dog doc]

Are the bumps itchy, red or inflamed? Have they lost hair? Do the bumps feel like they're IN the skin, or under it? If they're actually IN the skin (which you can try to differentiate by picking up the skin at the bump and seeing if it feels like it's in the picked-up fold or is in the underlying tissues), it could be all kinds of things... epidermal inclusion cysts, other cysts (cysts are generally benign), deep skin infection (the skin usually looks different than the surrounding skin in this case and may be itchy - but this is also true of some cancers), and of course tumors of the skin (either benign or malignant).

 

If it's UNDER the skin, that rules out the skin cysts, though there are other types of subcutaneous cysts, and there are aaaall kinds of masses, both benign and not. Fatty masses (lipomas) often do appear to pop up like a mushroom overnight, but then they grow slowly if at all.

 

General rules of thumb for the signs of "badness" in lumps and bumps:

1. Pain, itching or irritation

2. Ulcerated, non-healing wounds

3. Loss of hair

4. Change of color of skin

5. Recent rapid growth

 

Naturally, as in pretty much everything medical, there are exceptions, and while we used to think "once a cancer, always a cancer; once a benign lump, always a benign lump", this isn't really true... things have been known to change their minds, though MOSTLY they don't. The most definitive answer is to do a biospy and send the tissue to a pathologist and ask them what it is, but even that doesn't carry a 100% guarantee; there's even a particular cancer that has a benign look on pathology but a malignant behavior on the dog, and is named for that very paradox. My rule of thumb for that is that no matter what the path report says, if it's eating the dog's head, it's going to get treated like cancer. I'll believe the dog's body more than I believe the paperwork.

 

Naturally I can't diagnose it over the internet, but there really are many no-big-deal kinds of lumps. However, even if you biopsy and get a "benign" report back, any new lump should be checked... I've seen dogs with 10 lipomas and one mast cell tumor (a bad actor, mast cell tumors).

 

How old is your dog, BTW? Certain things are more likely at different ages.

 

I realise this probably isn't much help in this specific case, but sometimes having some general info is of use.

[diane allen]

OK, AK doc, here's another 'bump' related question. My BC had one small bump removed from her chest (it was right where her seat belt harness rubbed) - came back benign, just a sebaceous cyst. She has now developed about five of them on different parts of her body - one on her side, one on her haunch, one on the top of her head, etc. They're all about pencil-point size - maybe 1/8 to 1/16" in diameter. None are colored, itchy, etc. though most have appeared in the past six to eight months.

 

I should mention she had one other one which is like a (sorry, you queasy-stomach types....surely there aren't any of you here?!) big zit - it gets a 'head' on it about every four or six months, can be 'squeezed' out with some creamy gooey junk coming out. These other bumps have no head, and don't appear 'squeezable.'

 

They don't bother her, they only bother me when I find them and think its a tick, then realize 'its that same spot.'

 

WHY do they get these?!?

 

Just curious....

 

diane

[AK dog doc]

Hi Diane

This is easier to explain with pictures, but here goes.

 

In embryonic development, when the structures of the skin are developing, there are layers of cells that arrange themselves sort of like layers of a cake. There are structures that are supposed to originate in the deeper layers of the skin and penetrate up to the surface; hair follicles, for instance, originate below the surface of the skin in one of the layers, but the hair shaft travels up through the layers and out the surface of the skin (so that's sort of like a candle stuck into the cake, into the deeper layers). Another structure that's supposed to do the same thing is the sebaceous gland, which produces the oils that lubricate and protect the skin. This is sort of like a modified sweat gland (dogs don't have sweat glands except in their feet).

 

Meanwhile, as you know, we're all constantly shedding skin cells to the surface. This is because the progenitor cells (at the bottom layer of the "cake") are constantly growing new cells, which mature as they move towards the surface, and eventually they reach the top layer where they replace cells that have been shed.

 

Sebaceous cysts and epidermal inclusion cysts form when, during embryonic development, a little island of cells that is SUPPOSED to be arranged neatly in the cake-layer array instead gets trapped under or between the layers. These cells have no idea that they don't have access to the top of the cake, so they happily go along making their sebum or making their skin cells, and since these things can't make it to the surface of the skin, they gradually accumulate in a little wad under the skin. Sometimes, if they're near the surface, they'll make their own exit to the surface (hence the sebaceous cyst that you can squeeze and empty - satisfying, isn't it? ). Other times, if they're not near enough to the surface, they just eventually accumulate enough debris - dead skin cells, sebum, hair, whatever - that they form a bump big enough to feel. The rate at which this happens depends on how many cells you have trapped and what type. It's a little unusual to find hair in a cyst, but we do from time to time. Usually it's just sebum and dead skin cells.

 

Did that make sense? And was that the "why" that you were after?

 

Most of the time these are not that big a deal unless they're getting big or infected, or unless (as in your dog) they are in an area which gets rubbed.

[kaos]

My houndX has skin issues very similar to the ones diane was describing.

 

So far she has had two surgeries to remove two of them... the first was a benign cyst/tumour on her chest that she wouldn't leave alone and just kept worrying.

 

The second was a bump that kept growing/pooping/seeping/growing etc for over a year and then eventually stopped popping and just kept growing, it got to be the size of a baseball on her neck and our vet said it was an extreme autoimmune reaction to popped csyt. It had tendrils reaching out all over her body and it is a huge 5 1/2 inch scar now (which is pretty big on a 45 pound dog)

 

I do wish they had cut out the cyst that was only 1/2 cm away from the surgery site as it has now started the process all over again, and I am scared it will go the same way.

 

Do you think we should pre-emptively have all of her vaious lumps and bumps (currently about 6 on her body right now)removed at once or just leave them and wait and see if they keep growing or if they resolve on their own. I would rather not put her under again, but the one on her bum is growing and seems to be rather hard and sensitive, she definitely gets nervous about our checking it.???????

sara

[AK dog doc]

It's kind of a judgement call whether or not to have all the masses taken off at once. That's a lot of skin incisions, but on the other hand, it would mean a single anesthetic, a single recovery period, and a single hospital visit for all of them, so it might be worth it. If you dog has a strong tendency to have the bumps develop into trouble, it might not be a bad idea to get rid of them; but bear in mind that if she is inclined to grow these, she may keep on growing new ones, even if you take off all of the ones that are there now.

 

I guess if this were my patient, my thinking would run along the lines of: if I have to anesthetise her to go after one that is a problem, I might as well get as many as I can while I'm at it; but unless one of them IS bothering her (or the owner, or its behavior suggests "badness") - or unless I'm anesthetising for another reason, such as a dental - I might hold off for the moment and see how things develop. Some of it depends on the appearance of the masses and their behavior, and also on the size and site where they occur; also, the dog's other general health and age may factor in (in general I'd prefer to do an anesthetic on a young healthy dog than an old ill one.) And I'll mention here that in school Dr. S, my favorite surgical oncologist (a charming Aussie with a GREAT sense of humor) used to tell us: Some of the most dangerous words in veterinary medicine are "let's just watch it" - because sometimes you'll just watch it kill the dog. In this case it seems less likely, since the dog has a tendency to benign bumps (as some dogs do) - but as I said before, you can have 10 no-biggie masses and one really bad one (refer to the "signs of badness" in the earlier post, and if EVER in doubt, ask your vet).

 

Naturally I can't see your dog from here , so I'll suggest that you might bring it up with your vet and see what they think. They should be able to advise you, and if you bring up your concerns about having to repeatedly anesthetise to remove each mass as it starts to trouble her, as opposed to doing them all at once, they should be able to help you come up with a plan. Smaller masses are easier to remove and easier to get clean margins on if they DO happen to be bad actors.

 

Good luck with that, and let me know if I didn't answer your questions.

[CaseyGirl]

Thanks, Dog Doc. I believe these lumps are IN the skin and my vet says the couple she aspirated definitely were benign. However, she seems to want to remove all four at once and have more pathology done on them - though she's says there's no rush to do the surgery. My dog Casey is a 2-year-old female who's healthy in every other way. She hasn't had any hair loss, skin change, etc. In fact, I don't think she notices them except when I obsess with finding out what they are. They did grow rather quickly, but that's the only sign of badness.

[AK dog doc]

That sounds like a good plan. In a young dog, the chance of cancer, while not impossible, is is a lot lower (with a few exceptions, but those exceptions are usually NOT skin masses.) There are some benign types of bumps that can look bad but be really mild-mannered that show up preferentially in young dogs. This would reassure me if I were in your shoes. If there are minimal or no signs of badness you have a little wiggle-room on timing of the surgery.