Such correlation can be used to diagnose {HEAD ~ a tumor} or monitor the progression of {TAIL ~ a previously diagnosed tumor} 
Such correlation can be used to diagnose { HEAD ~ a tumor } or monitor the progression of { TAIL ~ a previously diagnosed tumor }
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL