Kangaroos general manager of football Brady Rawlings said scans had discovered a small tumour on Monday and it was fully removed on Tuesday afternoon.

He said the club was supporting the 30-year old and his family as he recovers from the surgery.

"This has all happened very quickly but our focus is on Ben and his family right now as they deal with this news and allow him to recover fully," Rawlings said.

"From the diagnosis earlier in the week up until this point, we've moved quickly to ensure Ben is in the right hands medically and that he and his family have the right support around them.

"We ask that everyone respects Ben and his family's privacy as this is a private health matter.

"Due to the sensitive nature of this news, we ask that the same level of respect and privacy be afforded to Ben's wider family, friends, teammates, coaches and staff."

Cunnington has been one of North Melbourne's best players this season, especially in recent weeks as the Kangaroos scored wins over West Coast and Carlton.

The midfielder, who grew up in Peterborough, had 27 disposals and nine clearances in the 39-point victory over the Blues last weekend.

Cunnington is averaging 26.8 disposals and 7.6 clearances a match this season. He has played 15 out of a possible 19 games in 2021.

He has earned the reputation as one of the AFL's toughest on-ballers across his 227 games since making his debut in 2010.

The Kangaroos will play Geelong this weekend.

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