@diverjer

No question is ever stupid IMHO. Only stupid people think that they know everything and do not ask questions ; ).

Prostate gland has myriad tiny ducts inside the gland that collect excretions before it is moved out of the gland and into much bigger ducts. When cancer cells invade those tiny ducts it is called IDC.

And one more thing - cribriform and IDC are completely different things and they do not always come together , actually have nothing to do with each other.

Regarding cribriform - those are also formations, they are not cells per se. Cancerous cells change the morphology and look part "empty" and make small circles that are "sieve like" - those are so called "cribrifom glands" or "sieve like glands" . Those circles can be measured under the microscope and the bigger the "circle" the worse it is since more mutations happen which in return cause that unusually big formation.

So - bottom line, one can have small cribriform, (not a big deal), big cribriform (big deal) and IDC alone or in combo with cribriform (big deal).