Lipoma and Sebaceous cysts


Infiltrative lipomas in German Shepherd

Question: Please I could use some input. I have a five year old female GSP. She had hernia surgery a year and a half ago. In about seven months the bulge came back. Our vet had said at the time of her surgery that it was a very fatty mass and it was very difficult to repair. Since the time of her surgery we watch and took x-rays which gave us no reason it would be anything else but the return of the hernia. On 12/06 she under went surgery again because we felt the bulge was getting bigger and we did not want any complications. The treatment confirmed what this new surgeon had said in an examination of Bonnie before the surgery. An infiltrative mass. The mass originated in the inguinal region and extended cranial between the muscle bellies of the body wall to the rib cage. It also extended medial to midline and lateral midway to spine. The mass was resected along with a portion of the body wall. there is residual tumor remaining. He also goes on to say that we feel this is an infiltrative lipoma and will require ancillary radiation therapy to prevent recurrence and treat residual disease. My questions to you is please what would your recommendation be? I can't seen to find to much information of this lipoma and we want to give her the best possible care so we can all enjoy each other for the years to come.

Thank you, Sherry By the way the pathologist report agreed with the diagnosis of the surgeon. Did say prognosis is favorable.

Answer: Sherry-

Infiltrative lipomas can be a difficult problem. In follow-up studies of dogs that have these tumors surgically removed but no other treatment (JAVMA July 15, 1994) the median time until recurrence of the tumors was 239 days. Radiation therapy appears to extend this interval significantly, but this is based on anecdotal reports only. I couldn't find a study that supported this claim. We have had one patient with this condition who we did surgery on three times before the clients finally agreed to radiation therapy, which worked to prevent future recurrences entirely, as far as we could tell. The dog lived at least eight years after the last surgery and radiation therapy.

Good luck with this.

Mike Richards, DVM 1/3/2001


Question: Hello, Dr. Mike,

We have a 12 year old German Shorthair who has numerous lipomas. As they appear, we have them needle biopsied by our vet and all have been benign. Currently, he has a fist-sized (and growing) lipoma on his neck/chest area, just below his collar, and another not quite so large at the juncture of his rear leg and flank. Neither are impeding his mobility at this time, but if they get larger, they might.

He has had large lipomas surgically removed in the past, but given his age and the fact that these 2 are where skin constantly moves when he walks, our vet doesn't want to remove them unless it really becomes a problem.

Our vet says he recently heard of a treatment that involves injecting saline into the lipomas and thus causing them to shrink without surgery, but he can't remember where and hasn't been able to find more info. I've also searched the Web with no luck. I wondered if this was something that you either have heard of or might know where we could find information about.

Thanks for any help. Your web site has been very useful to us in the past, but this is the first question I've had for you.


Answer: Grace-

I hate to disappoint you on your first question, but I can't find any references to treating lipomas with saline.

I can find articles on treating mast cell tumors with deionized water, though. This treatment was reported in the July 1990 issue of the Journal of Veterinary Research and it was used as an adjunct treatment to surgical removal of the tumors. It reported that dogs having both surgery and deionized water injections did better than dogs with surgery alone. I am not sure if this is what your vet is thinking of but it was all I could find. Since this is the only article I can find on this therapy, I am assuming that follow-up studies have not been successful in supporting this treatment but that may not be true.

Mike Richards, DVM 4/15/2000

Sebaceous cysts and Lipomas

Question: Champ is will be 12 in June He is a black Lab and not nuetered. He weighs in at 107 lbs.

He has always had enlarged nipples and sometime they have gotten crusty but no real problems.

About 3 months ago a lump, about the size of a quarter appeared. You could feel all around it and the vet send it was a fatty cyst and not to worry unless it changes.

I checked a week ago today , with no change. On the following Monday 2 days later it had grown to an oval shaped about 3-4inches long and maybe 2-3 inches across and firm.

On Tuesday we took him to a new vet (we have relocated) he did a tab and said it was mostly fat cells and some bacteria cells. He said probably a sebaecious cyst.

He put him on antibiotics, CEPHALEXIN, 3000mg a day. I was also to soak in twice a day with warm water. He said if it did not go down surgery should be done.

He has been on the antibiotics for four full days now with no significant change. There had been some fluid that formed in from of and behind the lump but has since been absorbed , at least most of it has.

Do you feel surgery is necessary at this point, if not how long should I give the lump to go down, if it even will? Is one week of antibiotics enough? I really would like to avoid surgery if possible.

I also give Champ 1000mg of Vit.C and 800 iu of Vit E and 740mg of Shark Cartilage. He has been on this Vit. plan for about 1 year.

He is eating well and playing and acting fine in every other way. We do live on a mini farm and he is always rolling in the dirt and horse manure. (could this have caused the infection)?

Any help you can give me would be greatly appreciated. Thank you also for helping with the E=mail problem. I did use the reply.

I also have a Dob/Shep with a similar lump on her belly (shes 11) but it has been there for 3 yr. also a fatty lump , and you can fell around it. What causes them?

Thank You Linda

Answer: Linda-

I usually do not surgically remove either lipomas (the fatty cell tumor your first vet suspected) or sebaceous cysts. However, under some circumstances we do recommend removal of these lumps.

We remove lipomas when they occur in a place that they cause irritation, such as in an "armpit" or on the sternum right where the pressure point is when a dog is laying down. Sometimes these will make a nipple sensitive and they have to be removed to get the dog to stop bothering the nipple.

I used to remove a lot of sebaceous cysts, trying to avoid letting them rupture. Over the years I noticed that when clients refused to have these removed most of them didn't rupture and some of them resolved without treatment. So now I just wait to see if they are going to rupture and remove them only if that happens, or if they occur in an irritating spot similar to the ones described for the lipomas.

We see an occasional patient who has a persistently irritated or infected nipple and we do sometimes have to remove these to resolve the problem. That doesn't really sound like what is occurring with Champ, though.

The other concern here is whether or not this is really just a lipoma or sebaceous cyst. It isn't really possible to be absolutely certain without removing the lump. I am pretty comfortable if I get a couple of consistent smears from aspiration that are supportive of a diagnosis of either lipoma or sebaceous cysts. The problem here is that you have gotten conflicting reports and that is a little bit worrisome. I think I'd probably want to do another aspiration from the lump to recheck the previous findings in this instance. The description makes a lipoma seem more likely.

If there is still any doubt about the lump's nature after the third fine needle aspirate, sending the smear from aspirate to a pathologist for review would be a good idea.

If it does finally seem important to remove this lump, it is often possible to do this with a sedative and local anesthetic in an older patient. We do this pretty frequently and have been able to remove even fairly large skin lumps without using general anesthetic.

I don't know what causes lipomas to form but Labradors and dobermans both seem to get a lot them, based on our patients.

Mike Richards, DVM 3/12/2000


Q: Hi: I have an 8 year old Black Lab that started getting lumps all over it's body. Most are very close to the skin surface and feel very loose. However, some recently occurring lumps seem to be less loose. The vet took a small biopsy with a syringe about a year ago when they first started occurring and determined that it was all fat tissue. What are these lumps? Should I be worrying about them? Is this something more common in Labs than other breeds?

A: Dogs develop fatty tumors called lipomas. Lipomas are normally diagnosed with aspiration of the lump and this is pretty reliable. Most fatty cell tumors are not malignant but a very small percentage of them are either locally invasive or do have metastatic potential. A very small percentage. Due to this, the standard of care is usually to leave these lumps alone unless they are causing some sort of functional problem -- like growing in the "armpit" region and restricting motion of a leg.

I don't know if Labradors have a particular sensitivity to these tumors but they do get a lot of them. Most dogs with these tumors will have more than one.

Lipomas can be removed but the risk of anesthesia, even though it is small, outweighs the risk of leaving the tumor alone and most vets are reluctant to remove them do to this.

Hope that helps. Mike Richards, DVM

Fatty Tumors - Lipomas

Q: Over the last twenty years, we have had four lovable mutts and one persistent problem: three of them have had substantial numbers of "fatty tumors." Our vet has been unconcerned about these...and over the years we have never really had any reason to worry since the only problem has been one of cosmetics. Our lab, though, now has two that are about the size of tennis balls, and one is under her front leg...and we anticipate we'll probably need to have them removed. We undertook this course of action once in the past (with another dog), and I found it pretty worrisome trying to keep a big active dog restrained for three weeks while all the stitches healed. To make a long story short, that dog ended up pulling all the stitches out...and I was a basket case. So here's my question: Is there any minimally invasive technique for removing/shrinking these tumors? I wouldn't mind the extra cost if a vet-school or other professional could save my dog...and me...a lot of pain and (mental) anguish. Many thanks.

A: I have often wondered if some variation of liposuction would work for these tumors. We have a surgical suction machine and I have even been tempted to try it but I keep waiting for someone to write a study on it first. I also wonder if more specialized suction equipment may be necessary. Anyway, I know of no other technique for removing these tumors other than surgery at this time.

All dogs are different and it is highly likely that this dog will leave the stitches alone. Most dogs do. I sure hope the odds work out for you!

Mike Richards, DVM

Last edited 01/30/05


Michael Richards, D.V.M. co-owns a small animal general veterinary practice in rural tidewater Virginia. Dr. Richards graduated from Iowa State University's College of Veterinary Medicine in 1979, and has been in private practice ever since. Dr. Richards has been the director of the PetCare Forum...