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  Discussion on When to worry? When to not?
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Posted on Thursday, Jun 21, 2001 - 6:17 pm:

Dr. O,

I recently had the vet out to check two skin areas on my horse that appeared suspicious to me. The reason I am posting here is because while the vet was unconcerned, I am wondering if I should seek a second opinion … or am I just being obsessive. (Believe me, I would rather just forget it and not worry! It is just I am having a little trouble getting past the 'visual' only exam, and if a biopsy really was called for.) Any comments would be greatly appreciated.

Background: 11 yr old draft - app cross, pink and black skin, white hair coat with black spots
During spring shed-out I noticed a patch of hairless skin about the size of a quarter, with some raised sections to it, in the area between there the hind leg attaches to the body and the sheath. It was so small and innocuous, I didn't really think much of it. A few weeks ago I noticed a small amount of blood on this spot. I cleaned it up and it hasn't bled since - but its persistence gave me cause to wonder about it. So I came to your site and read up on some skin things, and I read an article in an old Equs about sarcoids and such that had some really excellent photos. That article really stressed the need for a biopsy to know for sure what you are dealing with. After reading I checked my horse again and noticed a small nodule (a little smaller than a pea) in the corner of his eye. It is present in only one eye, so you can by comparison see that there is definitely a bump there. In truth, I would not be able to say how long that had been there (maybe it always has been there?). I decided to get a professional evaluation.

Vet's exam and 'diagnosis':
The vet felt completely unconcerned about the hairless spot on the skin between his leg and sheath. He said he felt sure, based on visual inspection, that it was not a melanoma, SSC or even a sarcoid - it just didn't look like one to him. He conceded though it was the right location for one. He suggested a poorly healed bug bite.
Regarding the black nodule in the corner of my horse's eye, he agreed that it was different than the other eye, but was still unconcerned. He suggested it might be a mole. He showed me the third eyelid and remarked how nice and smooth it looked, indicating it was healthy. He said that little black section on the third eyelid was just part of his normal coloring. Just to be sure (for myself) about what he was saying, I asked him if this was his horse that he loved very much, would he want to do a biopsy or anything - just to be sure. He said no. I accepted his opinion, thanked and paid him.

Those Nasty Worries:
From your own site: " SSC is the most common tumor of the equine eye and surrounding tissue. The mean age of onset is around ten years … The incidence is higher in drafts, Appaloosas, and geldings. " Well, gee, my guy gets the triple whammy on 'higher incidence', and is also 11 years old. Given this, would you be more likely to biopsy a bump or splotch as an attending vet? Or, do you feel that based on your experience, you can safely determine what's NOT a problem by visual inspection alone? I know you can not see my horse, I am more asking for you frame of reference on approaching these types of problems.

Are biopsies difficult to do? When I asked the vet about how they are done and approximate cost he was vague and switched the subject. Perhaps he didn't want to waste time telling me information that he felt was not relevant to what he was seeing. I was wondering particularly about doing a biopsy near the eye - would that require sedation?

Also, regarding your site, it states: " SCC often appears as a tumor or ulcer on the skin. SCC can be differentiated from less serious conditions by its irritated or bleeding appearance. It is commonly found around the eye or in the eye itself, on the prepuce" Do you mean that if SSC appears in the eye, it will often be irritated and bleeding in appearance? Or is that just when it appears on the skin?

Thanks for the help.
Mary

Posted on Saturday, Jun 23, 2001 - 12:00 pm:

Irritated areas on the pink skin of an Apoolosa particulary near mucocutaneous junctions always rate a high level of suspicion. SCC carcinoma almost always appears irritated and bleeds easily. I suppose there could be exceptions but cannot think of one that I have seen. However a pigmented smooth tumor does not sound like SCC. Biopsy around the head would always be easier if the horse is sedated.
DrO

Posted on Monday, Apr 22, 2002 - 5:55 pm:

Dr. O,

I am posting at the end of this thread because I am the same person, with the same horse mentioned in the original post, and I have some follow-up concerns and questions. The horse is now 12; a draft-app cross, pink and black skin, gelding.

Since the original post in June 2001, no diagnostic test have been done on this horse (other than visual inspection). The lesion under his hind leg remained fairly consistent. On occasion, it will seem to ‘erupt’ in the center of the lesion and bleed a very small amount. In a few days, it seems to heal up and the ‘erupted’ skin flakes off like a scab, leaving the original circular lesion of thickened, hairless skin the diameter of about a quarter. The skin at the lesion site is dark gray. The smooth black nodule in the corner of his eye remains completely unchanged.

In March 2002, a patch of nodules appeared on his left shoulder, all of them appearing at once. At first I thought it might be bug bites (although very early in the season) or an allergic reaction. However, the nodules have persisted. They are numerous (25?) in a cluster spanning about 5 inches in diameter. The nodules are small (pea sized), firm, definitely IN the skin rather than under it, normal hair covering. He does seem to enjoy having them scratched, but I don’t know that this is significant since the points of his shoulders have always been a favorite place to have scratched – scratching either shoulder draws strong reaction.

About two weeks ago I had a vet out to take a look again(same vet as a year ago). He now says the lesion under his leg is a sarcoid, but still recommends no further action. Due to a scheduling mix-up, I was not able to be present, and he missed inspecting the nodules on the shoulder.

I have decided to get a ‘second’ opinion from another vet (unfortunately in the same practice). My appointment is this Friday. At this point, I want to insist that a biopsy of the lesion under his leg be taken. I am also thinking a biopsy of one of the nodules on his shoulder should be done. Below is a list of questions. I’m just trying to be ulta-prepared to meet with this second vet. I will also bring along copies of your articles for my reference.

Thanks for any input. I am looking forward to getting this settled once and for all – then at least I can pick a course of action.

The lesion that bleeds and then appears to heel over, in your experience have you seen that with SSC? With sarcoids? Or neither?

Would you feel a biopsy is a reasonable test? Both locations?

Is a needle biopsy or ‘scraping of skin’ preferred?

If it is a sarcoid, in your experience, does the biopsy represent a significant risk of aggravating/activating the growth or aggression of the sarcoid? (like a removal attempt does)

What is a typical turn-around time for receiving biopsy results? Days? Weeks?

Is is reasonable for me to ask for a copy of the lab report?

Should a course of treatment be started before results are known??? I thought I saw something in your articles on this, but I’m not sure how you can do that without the results. How do you know what to treat with?

Regards,
MaryS

Posted on Tuesday, Apr 23, 2002 - 8:38 am:

Taking your questions one at a time:

1) The lesion that bleeds and then appears to heel over, in your experience have you seen that with SSC? With sarcoids? Or neither?
Both can bleed.

2) Would you feel a biopsy is a reasonable test? Both locations?
I really cannot answer this without looking. Yes if the lesion is unknown and it would be reasonable to biopsy both if there is doubt they are the same.

3)Is a needle biopsy or ‘scraping of skin’ preferred?
Needle would be better, but a punch biopsy would be best.

4) If it is a sarcoid, in your experience, does the biopsy represent a significant risk of aggravating/activating the growth or aggression of the sarcoid?
Yes this is possible however if treatment is going to begin in the next week or two I do not think the risk is "significant".

5)What is a typical turn-around time for receiving biopsy results? Days? Weeks?
About a week but this varies tremendously.

6)Is is reasonable for me to ask for a copy of the lab report?
Absolutely

7)Should a course of treatment be started before results are known???
Not if the list of possible differentials for the lesion contain different treatments.
DrO
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