Sampling Inguinal Lymph Nodes

Re: Sampling Inguinal Lymph Nodes

Braden Collins — Mon, 21 Oct 2013 10:27:29 GMT

This from Winthrow and McEwans:

Lymphatic drainage of normal mammary glands is very complex, with documented drainage occurring to multiple ipsilateral lymph nodes and even to contralateral lymph nodes. the amount of variation in lymphatic drainage increases in the neoplastic mammary glands. thus exclusive anatomic sampling of nearby lymph nodes is not sufficient for accurate lymph node staging and may miss the presence of locoregional disease.

Re: Sampling Inguinal Lymph Nodes

Braden Collins — Mon, 21 Oct 2013 10:21:58 GMT

Would the one star person like to present an alternative opinion?

Re: Sampling Inguinal Lymph Nodes

Braden Collins — Mon, 21 Oct 2013 06:27:09 GMT

[quote user="John Flynn"]

[quote user="Anthony Dennison"]survey radiographs and sampling the draining LNs[/quote]

Is this likely to change the treatment or prognosis for this patient?

[/quote]

Definitely worth discussing adjunctive chemo with the owners before you go chasing metastatic spread. If chemo is not an option there's not much point in finding out if it has spread or not at this point.

Re: Sampling Inguinal Lymph Nodes

Thomas Johnson — Sat, 19 Oct 2013 09:55:08 GMT

[quote user="John Flynn"]

The dog has of late been used as a research subject for medical lymphatic study - this resulting picture is a helpful summary of cutaneous drainage that might be expected:

http://meeting.aaps1921.org/abstracts/2012/images/g173_1.jpg

More can be read at: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3722290/pdf/pone.0069222.pdf

[/quote]

Why only one star for this post? I thought it was fascinating, 5 stars from me.

Re: Sampling Inguinal Lymph Nodes

David Mills — Fri, 18 Oct 2013 14:53:31 GMT

[quote user="John Flynn"]

[quote user="Anthony Dennison"]survey radiographs and sampling the draining LNs[/quote]

Is this likely to change the treatment or prognosis for this patient?

[/quote]

Hmmmm exactly my thoughts. I'd be leaving this dog alone unless its going to make a significant difference to management with results.

Re: Sampling Inguinal Lymph Nodes

Matt Hilary — Fri, 18 Oct 2013 11:40:38 GMT

Significant chance of a false negative result with FNA of draining lymph nodes, surely (missing neoplastic cells entirely). Cell preservation often poor as well. You'd get much more chance of a reliable result with surgical removal though appreciate it's more invasive.

Re: Sampling Inguinal Lymph Nodes

John Flynn — Fri, 18 Oct 2013 11:34:22 GMT

The dog has of late been used as a research subject for medical lymphatic study - this resulting picture is a helpful summary of cutaneous drainage that might be expected:

http://meeting.aaps1921.org/abstracts/2012/images/g173_1.jpg

More can be read at: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3722290/pdf/pone.0069222.pdf

Re: Sampling Inguinal Lymph Nodes

John Flynn — Fri, 18 Oct 2013 11:24:44 GMT

[quote user="Anthony Dennison"]survey radiographs and sampling the draining LNs[/quote]

Is this likely to change the treatment or prognosis for this patient?

Re: Sampling Inguinal Lymph Nodes

Sylvia Wilson — Fri, 18 Oct 2013 11:10:24 GMT

In humans, they inject a dye into the appropriate area a couple of hours before surgery, incise over the expected location of the LN and sample/excise the one(s) coloured with the dye. (Well, that's what they did with my mammary tumour, anyway). Can't see any reason why that wouldn't work in animals, although I stand to be corrected. Your local radiology/oncology department may be able to help.

Re: Sampling Inguinal Lymph Nodes

Robin Grimmer — Thu, 17 Oct 2013 16:14:57 GMT

You'll have to knock it out to get decent chest films, so maybe just excise the lymph node and send for histo?

Re: Sampling Inguinal Lymph Nodes

Andrew Kent — Thu, 17 Oct 2013 15:37:27 GMT

The inguinal lymph nodes sit in the fat just caudal to the mammary chain, the best way to assess them is to remove them at the time of surgery for histo. Failing that if they are not palpably enlarged they will be difficult to find and sample, you could try looking with ultrasound to see if they are visible. Is there anything to feel in that region?

the other nodes to consider are the auxiliary lymph nodes which lie cranial to the mammary chain and drain the cranial gland or even the popliteals which I believe drain the caudal gland in some dogs. The problem is that neoplasia can alter the lymphatic drainage so it is difficult to be sure where the mass was draining to.

if you can't feel them and they are not obvious on ultrasound I think it will be difficult to take samples.

Andy

Re: Sampling Inguinal Lymph Nodes

James Laidlaw — Thu, 17 Oct 2013 15:36:49 GMT

Ultrasound guidance would be easiest - get an anatomy text for location and scan/aspirate.