Mast Cell Tumors in 11.5 year old Yorkshire Terrier

My 11.5 year old Yorkshire Terrier had 3 mast cell tumors (all Grade 2) removed in late April. One of the mast cell tumors was on her front right ankle therefore it could not be completely excised and radiation is being recommended for that area. The other two tumors were removed with clean margins. The report reads for the ankle specimen that "individual and clusters of 2-3 mast cells extend to the deep section margin...." meaning dirty margins. The stats for the ankle specimen follow:

KIT Pattern = 1
Ki-67 = 3
PCNA = 70%
AgNORs/cell = 1.1
AgNORxKi-67 = 3.3
C-KIT mutation PCR = negative

Also, the report noted neither vascular nor lymphatic invasion was observed in any specimen and the overall proliferation markers in all three specimens do NOT support poor prognosis. Her bone marrow was also tested for cancer and those results are negative.

My questions are:
1. Should we wait and see what happens (instead of treating with radiation) given her history of multiple mast cell tumors, age, etc.?
2. If we do wait and a mast cell returns to that area is radiation still a good option to destroy the cancer activity there?
3. Are there holistic treatment options for her instead of radiation and if so, what are they?
4. If we choose radiation treatment, what are the pros/cons to this treatment especially with consideration to her age? ( Please note that I expect her to be sick a lot during the days of treatment as she has to be given anesthesia each day of radiation and she doesn't take particularly well to that.)
5. Are the possible negative side effects of radiation worth it given her age of 11.5 years?
6. What is her prognosis or potential life expectancy if we wait and see versus proceeding with radiation treatment?
7. Is there any correlation to the number of mast cell tumors and the cancer returning?

Out of her three tumor removals, her ankle took the longest time to heal and has only recently done so.  With it now healed,  we feel we should come to a decision of whether to wait and see or proceed with radiation treatment. I'd appreciate any feedback to help us with this difficult decision. Thank you!


Best regards,
Leslynn

[lindapalm]

Scroll down to Animal health General on the right side of this page, and Click on it, then click on Ask a Vet, perhaps he could give you some good advice.  Good Luck,