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Featuring Demian Dressler, DVM and Sue Ettinger, DVM, Dip. ACVIM (Oncology), authors of The Dog Cancer Survival Guide

Dog Cancer Surgery: They Didn’t Get It All Out

Updated: December 20th, 2019

Sound familiar? Did this happen to anyone out there?

Removal of all the cancer cells from the body during surgery is pretty important.  How can we tell?

The most important thing to do is get that biopsy report.  Some don’t want the extra cost.  “Just get it out” is a line I have heard from time to time. However, the report from the path lab can be absolutely critical.

Why does it matter?  Well, there are a couple of reasons.  First, the pathologist can evaluate the borders of the tissue I, or your vet/oncologist, submit after removal.  This is called comprehensive margin evaluation.

This evaluation tells us if there are cancer cells still left in the dog or not, around the surgery site anyway.  If there are cancer cells at the border of what gets turned in to the lab, there are probably some left in the dog.

So, if you get the path report back and there are cancer cells at the edge of the submitted specimen, it would be wise to go back in and remove more tissue. Yes, I am talking about a second surgery.

Some cancer types spread out around where the lump actually is resting.  So the dog will have cancer cells around the tumor that you can’t see with the naked eye. Some examples are osteosarcoma, some mast cell tumors, squamous cell carcinoma, fibrosarcoma, hemangiopericytoma (nerve sheath tumor), some mammary cancers (inflammatory carcinomas especially), hemangiosarcoma, malignant melanoma, and more.

In these cases, sometimes a wide excision (removing more than what “looks like” the cancer at the time of surgery is the way to go.  A fine needle aspirate or small biopsy before surgery can actually save cost in the end, by ascertaining whether a wide excision is needed before surgical removal.

Best to all,

Dr Dressler


Leave a Comment

  1. Tomi Manikas on September 17, 2013 at 5:39 am

    Dear Dr. Dressler – My beloved 14 year old rescue Yorkie/Maltese had surgery last month to remove an aggressive melanoma from her groin just above her vulva. Because of the location, the surgeon was not able to remove it all, was only able to get thin margins. She had a similar surgery 3 years ago which was successful. She also had 2 mastectomies at the same time. One week after suture removal, she had a recurrance of pancreatitis, which she had after another surgery 2 years. ago. Also, not only did the tumor reappear, with additional new lumps but now her vulva is extremely swollen and gets bigger day by day. The vet did an FNA and the results were aggressive melanoma also on her vulva. He told me there was nothing more to do, except love her and hug her and at some point she will not be able to eliminate and that would be the time to euthanize her. I do not think I can try Apocaps because of her pancreatitis, which is under control with small frequent feedings of HIlls Prescription I/D Low-Fat dog food.

    My vet knows I have no money left to consult with an oncologist, and I wouldn’t even want to put her through chemo or radiation anyway. So, do I just sit and do nothing?

  2. Deborah Nolen on January 8, 2011 at 12:10 pm

    Dear Dr. Dressler, I have been reading your books, advise and help sites for 4 months while taking care of my 13 yr Female Collie Mix. I found a lump in Aug and promptly had it removed, it was found to be Chondrosarcoma close to her middle right side rib. No involvement of rib or lung. Margins were not completely clear and I was told the nature of this cancer is to reoccur in probably the same location. She recovered quickly from surgery, already for a year having only organic meats & vegs, I began a complete support of supplements & vitamins. She is alert, happy & still playing like a young girl, BUT the new tumor has steadily grown and is now about the size of a softball. She seems to have no pain at this time, but I have tramadol & tapoxolin if necessary. I am trying so hard to boost her immune system enough to fight the cancer cells, but I am wondering just how else I might help her. I feel it is perhaps too late for a 2nd surgery? I have even hesitated to have another digital x-ray because of the radiation. Is there anything you might offer me & my girl. Thank you for all you have done to educate animal lovers. Sincerely, Deborah

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