Incidental finding of gross lesions on spleen during spay

My 16 month old goldendoodle was spayed today and the vet reported gross lesions on her spleen. It was also firm. Picture attached.   She’s recommended an ultrasound after recovery and 2nd opinion from an Internest to diagnose & recommend treatment options (likely observe or splenectomy). Prior medical history is unremarkable. No other symptoms or concerns outside of potential ear infection. Not much history before we adopted her at 5.5months. She had been with a family who had to rehome due to their son being too aggressive and not understanding she couldn’t “be free” (aka - open front door to busy street). I get the sense she may have had some solo adventures but no injuries were reported. I also don’t know what “too rough” means, but am curious if there could have been blunt force trauma even if accidental. She is a bit skiddish with strangers but nothing compared to a prior rescue. She came from a rural “breeder” but no contact info was provided by the former family. Most likely an accidental litter or backyard breeder. I plan to follow my vet’s recommendation for ultrasound and go from there, but any insights would be appreciated. She’s been an amazing addition to our family & I want to ensure we address this quickly & properly to give her the best chance at a long, healthy life. Thank you for reading and providing insight!

Hello there.  In my experience, it is very difficult for a first-opinion ultrasonographer to tell the difference between cancer of the spleen and nodules arising there for any other reason, for example inflammation.  It sounds as though your vet couldnt identify the lesions when they  observed them directly, so I wonder why looking at them using an ultrasound machine would be useful now?   It may be worth asking your vet whether it would be preferable to carry out a biopsy to distinguish between the two, in order that the lesions are diagnosed correctly.   They could also ask for second opinion ( expert ) guidance on this, for instance by showing those pictures / the clinical notes to their friendly lab pathologist.

Of course there may be factors involved in this case that I don't understand, but it is worth asking the question.