What is Your Diagnosis and Treatment? Acute onset of a vaginal mass in a pit bull.

Betty, a 2 year old in tact female pit bull.

"Betty" is a 2 year old in tact female pit bull with an acute onset of a vaginal mass. The owners just noticed the problem today and presented her to the emergency service. She had a small amount of pinkish vaginal discharge for a few days before her owners discovered the mass. They do not remember when she was in heat last. She had no other history of any medical problems.

The dog was bright and alert and her physical examination was unremarkable except for the vaginal mass. 

Vaginal mass on Betsy

What additional diagnostic tests would you do?

What is your diagnosis and how would you treat this problem?

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