Is Mini-ITX the smallest formfactor for this build?

[Ike582]

What is the smallest form factor for this config that I can assemble?
- Latest generation Intel core i5 cpu + MB with Intel HDGraphics onboard + cooler
- 16gb ram
- 250gb SSD
- 4 external USB slots in the back + 2 in front
- Blu-Ray reader

I prefer to build myself and Ultra-Compact seems to be sold prebuild only.

My Mini-ITX is not nearly full with a Nvidia GTX card on top.
So I guess smaller must be possible.
It's for mom and pop and their huge genealogy files and small living space.

 

[Suztera]

The mini-STX is smaller now.