Hemangiosarcoma Question

[Tracy1974]

In August 2009 we lost our akita shepherd mix (9 years old) to Hemangiosarcoma.  The tumor started in the spleen, spleen was removed.  She survived 18 months post surgery with treatment and had great quality of life.

Yesterday our spitz mix, who is also 9 years old, was also diagnosed with Hemangiosarcoma.  We are not sure where the primary tumor is at this point, however he has tumors widespread throughout the lungs.  

I understand the disease very well and know the prognosis is not good.

My question is this...I know that there is really never a "why" as there are too many variables and not enough research but the odds of this happening twice within months of eachother to dogs the same age in the same household but completely different breeds has to be relatively rare.  I am curious as to any opinion that can be offered on environmental links to the disease.  They have both lived a very healthy lifestyle and have both eaten the same food for their entire lives.  I know that I could search the internet and find problems with just about any brand of food but it seems to me that this isn't coincidental.

Any thoughts?

[Arnold L Goldman, D.V.M.]

In echoing Dr. Humphries reply, I'd add that all forms of cancer have in common their origin in a mistake in cellular division. Genetic and individual characteristics (not necessarily external environmental in nature) influence the likelihood of such mistakes.
With so much cellular division going on in every tissue and organism, its a wonder there is not even more cancer than there is. Hemangiosarcoma is very common and often originates in the right atrium with metastasis to the spleen, lungs and elsewhere, in other words anywhere. I agree that this is likely an unfortunate coincidence. Internet "experts" aside, food would be an improbable factor in this type of cancer. I'm sorry.

[Jim Humphries, B.S., D.V.M.]

I would say this is one of those very unfortunate extremely rare coincidences.  Hemagios are pretty common among tumor types in dogs and you seems to have more than your share.  

I would not spend time pursing an environmental or nutritional cause.  If you found anything you suspected in the literature, it would all be supposition as you would need actual medical / cellular / chemical evidence to prove your case.  You will not be able to get that.  

Cancer strikes one in 4 pets and the odds are even higher in pets over 10 yrs.  I am very sorry and I wish we had more answers both in pets and in human cancer.