查了下: (1)脾腫大可能與其它病相關,不一定是脾本身的問題. (2) 脾生癌的話, 有可能不擴散

(3) 脾可以被完全切除而貓仍然正常生活. 

In most instances, the causes of an enlarged spleen in cats are due to a secondary condition and not from the spleen itself. These triggers can commonly include immune disorders, bacterial infections, tumors of the spleen, inflammatory bowel disease, and injuries to the abdomen.

參考鏈接:  https://www.aspcapetinsurance.com/resources/feline-spleen/#:~:text=In%20most%20instances%2C%20the%20causes,and%20injuries%20to%20the%20abdomen.?