Neoplasene is a holistic chemotherapy which is exclusively provided by Buck Mountain. Here is there website link: Buck Mountain
As I have no experience with Neoplasene I called the company today and spoke with Dr Fox. He says that Neoplasene has absolutely no history of causing any liver problems whatsoever. He says that since Neoplasene preferentially seeks out neoplastic (cancerous) cells, he thinks that the Neoplasene may have 'found' some cancer within the liver and is attacking it.
He asked on the dose and weight of your cat. Since I didn't have it - he states that he assumes that for a 10lb cat, you are on the 300 versus the 75mg. If at the 300, this is a strong but good dose for the situation. As long as your cat is feeling well and the liver enzymes are not dramatically elevated, then (from what we can tell without knowing more about your cat's medical records) this dose is likely helpful.
I hope this helps.
I would continue to follow the ultrasound changes and any blood abnormalities. Also if the diabetes test (blood and urine sugar levels) are negative, then they are negative. Your cat cannot get liver changes associated with diabetes before the tests would become positive as with other diseases.
Please let us know you everything goes. Best of luck