Cuts on chest need treatment (7)
I believe the answer is:
notches
'cuts' is the definition.
(I know this)
'on chest need treatment' is the wordplay.
'need treatment' is an anagram indicator (I've seen 'needs treatment' mean this (letters must be processed or treated)).
'on'+'chest'='onchest'
'onchest' is an anagram of 'NOTCHES'.
(Other definitions for notches that I've seen before include "Small v-shaped cuts" , "Small indentations found on chest" , "Makes small indentation in" , "V-Shaped cuts or indentations" , "Nicks" .)