Can I upgrade from PSE 10 to PSE 2018?

Yes, please feel free to download the setup and install PSE 2018 on your system from the below link:

Download Photoshop Elements | 2018, 15, and 14

You can use it for free for 30 days and if you like, you can buy it. You dont have to uninstall or remove the existing version from your MAC unless you need to free some space for installation of 2018.

Regards,

Vipin

Perhaps also consider "an upgrade" to Affinity Photo, which is written with the Mac platform in mind, and is both more powerful and less expensive compared to Elements. It runs really well on a Mac, and is more of a Photoshop competitor.

julioa27292847  wrote I have PSE 10 for Mac and I want upgrade to PSE 2018 for Mac too... Can I do it?Photoshop Elements  !

There is no "Upgrade." Any reference to upgrade is a marketing maneuver. Each version of the program is independent and can reside on the same computer. You can test a free 30-day trial of PSE2018 to see if it works on your machine. If you like it, you may purchase the license subsequently.