Tumour grade — no malignancy discovered (7)

I believe the answer is:

adenoma

'tumour' is the definition.
(adenoma is a kind of tumour)

'grade no malignancy discovered' is the wordplay.
'discovered' says the answer is hidden in the clue (remove the letters covering the answer in the clue).
'ADENOMA' is hidden in the letters of 'grade no malignancy'.

(Another definition for adenoma that I've seen is " Benign tumour".)

I've seen this clue in The Hindu.

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