Carcinoma of apocrine glands of anal sac

Re: Carcinoma of apocrine glands of anal sac

Hannah Wynne Richards — Tue, 20 Jan 2015 13:20:21 GMT

Brill

Wynne

Re: Carcinoma of apocrine glands of anal sac

Rob Davis — Tue, 20 Jan 2015 13:06:17 GMT

I though I would post an update on this case for anyone interested: the owners decided against any follow up surgery, preferring to monitor. 12 months down the line and there is no palpable regrowth or signs of metastasis so far. I will try to remember to post longer term updates in due course.

Re: Carcinoma of apocrine glands of anal sac

Mark Holmes — Fri, 10 Jan 2014 21:26:49 GMT

[quote user="Glenn Hodgson"]

[quote user="Mark Holmes"]And don't worry about incontinence post analysis sacculectomy never had one, seen one or heard about a case. Very very unlikely. Nerves to anus dorsal you operate ventral and lateral to anus.

[/quote]

I agree! I hear this talked about alot but have never seen the likes. I am of the opinion that a careful ansl sacculectomy is far less likely to cause a problem than a ruptured anal gland.

[/quote] I would go further, I think the overinflated risk discourages people from removing anal sacs when it is easy and generally low risk. The dog has several abscesses , a variety of fistulas, scarring and granulation tissue develop, they then attempt removal when it is much more difficult and hence much more risky. They are a doddle when addressed early a pig when postponed.

Re: Carcinoma of apocrine glands of anal sac

Glenn Hodgson — Fri, 10 Jan 2014 20:54:55 GMT

[/quote]

I agree! I hear this talked about alot but have never seen the likes. I am of the opinion that a careful ansl sacculectomy is far less likely to cause a problem than a ruptured anal gland.

Re: Carcinoma of apocrine glands of anal sac

Gerry Polton — Fri, 10 Jan 2014 18:13:58 GMT

Hi Tim

I would almost certainly not use any adjuvant therapy in this case after revision surgery. I reserve adjvuant chemotherapy for the large (stage 3b) lymph node metastasis resections. To date there remains an absolute absence of evidence that chemotherapy actually results in a survival benefit. There are papers which report shrinkage of gross tumour (in about 50% of cases). However, the application of chemo after surgery, when the patient is, one assumes, in remission, is entirely based upon a presumption of benefit. I am not saying that therefore there is no benefit. However, carboplatin is exceptionally expensive. I personally believe I achieve far better outcomes for these cases by being on top of their disease for the long term future than I ever used to by giving a course of adjuvant treatment and leaving them to their own devices. Of course, these two options do not need to be mutually exclusive but doing both is even more expensive!!! I try to be as effective with owners' resources as I possibly can, as I am sure everyone else does. There is no right answer...

Gerry

Re: Carcinoma of apocrine glands of anal sac

Gerry Polton — Fri, 10 Jan 2014 18:08:44 GMT

Yes. I do believe that there is a beneficial impact of NSAIDs in a number of canine tumours. The most famous and the most significant is transitional cell carcinoma of the urinary bladder. Other tumour types which are feted to experience a beneficial (anti-neoplastic) effect include colonic adenoma/adenocarcinoma, sinonasal carcinoma and oral squamous cell carcinoma, the latter when the NSAID is given in conjunction with carboplatin. I do not have any record or knowledge of an anti-neoplastic effect of meloxicam or any other NSAID in this tumour context. That does not mean that it is not possible, but I do believe it to be unlikely that a benefit would be seen.

Great initial question and great discussion.

Gerry

Re: Carcinoma of apocrine glands of anal sac

Tim Charlesworth — Fri, 10 Jan 2014 18:06:09 GMT

[quote user="Gerry Polton"]

[/quote]

Mark, I would say that I concur: it is extremely unlikely that severe faecal incontinence would develop after anal sacculectomy... provided we are only talking about removal of an inflamed anal sac and only talking about complete loss of defecatory continence. However, with larger resections, true loss of nerve function can occur and, of greater pertinence to routine anal sacculectomy, incontinence does occur in shades of grey (or brown? sorry!). Even though we might not, owners do consider faecal smearing on a cream carpet definitely counts as incontinence, even if the cause was actually simply post-operative inflammation causing altered sensation and function. The point I am making is that we shoud be careful about how we explain these risks. I do concur with the essence of your point.

Have a good weekend, all.

Gerry

[/quote]

HI Gerry, completely agree - we've seen a range of "incontinence" from the "failure to crimp" through to the "bumprint" and temporary faecal incontinence. Prob all driven by dissection and subsequent healing of the sphincter muscle rather than nerve injury given that all are back to normal a week or 2 down the line. I'm interested by what you said about reoperation - would you still advise postoperative chemotherapy (Carb etc) or would you just go for wide excision in the absence of detectable mets on CT/ultrasound etc? Have had a run of these recently so interested in your approach.

Many thanks,

Tim

Re: Carcinoma of apocrine glands of anal sac

Tim Charlesworth — Fri, 10 Jan 2014 18:00:25 GMT

[/quote]

I agree that the risk of incontinence is very low indeed but the caudal rectal nerves come in from the pudendal and enter the external sphincter "slightly ventral to the middle" (Miller's anatomy) so some care here is warranted..

Re: Carcinoma of apocrine glands of anal sac

Rob Davis — Fri, 10 Jan 2014 17:34:54 GMT

Thanks for that, Gerry. I will have a chat with the owners and see what they want to do.

I agree that this risk is often overstated, but I was a little more concerned with this surgery as the mass was deep to the anal sac and I ended up with quite a deep hole.

[quote user="Mark Holmes"]I have not had any great success with chemo BUT I have had several do remarkably well on metacam --Metacam having some inhibitory effects on certain types of carcinoma.[/quote]

Any thoughts on metacam, Gerry?

Re: Carcinoma of apocrine glands of anal sac

Gerry Polton — Fri, 10 Jan 2014 16:57:55 GMT

[/quote]

Have a good weekend, all.

Gerry

Re: Carcinoma of apocrine glands of anal sac

Gerry Polton — Fri, 10 Jan 2014 16:51:14 GMT

Hi Rob

This was a small mass and prognosis in these cases is very much related to tumour size. So long as there is no current evidence of metastasis to the regional lymph nodes or the lungs, revision surgery is extremely likely to cure this patient. Therefore, I would not be considering post-surgical medical treatment at all. I would consider post-surgical surgical treatment.

The revision surgery does need to conform to basic oncological surgery principles which means that the whole of the previous surgical site must be removed en bloc. There is a risk of a degree of incontinence but it is very important to state that the degree of incontinence we are talking about is that the dog might fail to 'bite off' (excuse the choice of words) a stool after defecation leaving a slightly soiled anus which can be easily remedied with a wet wipe when the dog comes back indoors. This tiny continence issue is likely to persist for a couple of weeks but can last longer.

If abdominal ultrasongraphy reveals a medial iliac lymphadneopathy, or if thoracic radiography reveals pulmonary metastasis, I would act differently. Write to us again if that is the case. However, I would emphasise that I consider either of those eventualities very unlikely indeed.

I do indeed love all things anal

Gerry

Re: Carcinoma of apocrine glands of anal sac

Mark Holmes — Fri, 10 Jan 2014 16:45:16 GMT

And don't worry about incontinence post analysis sacculectomy never had one, seen one or heard about a case. Very very unlikely. Nerves to anus dorsal you operate ventral and lateral to anus.

Re: Carcinoma of apocrine glands of anal sac

Mark Holmes — Fri, 10 Jan 2014 16:41:30 GMT

I have not had any great success with chemo BUT I have had several do remarkably well on metacam --Metacam having some inhibitory effects on certain types of carcinoma.