FIP can do this but the wet

FIP can do this but the wet form is usually a young cat disease (dry form older cat) whereas this case is an older cat. Bad necrosing pancreatitis can do this as well and what I used to think was straightforward carcinomatosis/lymphomatosis in older cats or FIP wet form in younger cats turned out to be bad necrosing pancreatitis in another recent case on repeated fna and histopath. So we know that things that do this are usually multicentric badness but its important to get samples. FIP would come up granulomatous inflammation on fna wheras in this case of the  month carcinoma cells were abundant. But as I said in another recent case I had that liook just like this pancreatitis was present on every of the  numberus precise samples I took on FNA and confirmed on post mortem as “just” incredibly extensive necrosing pancreatits in a geriatric diabetic cat that had similar effusion and nodules throughout the omentum. The appearances are similar but the histopath/cytology is often different. So I would say the end result is straightforward, because things that do this aren’t good, but the processes are different.