#1	MeSH descriptor: [Colorectal Neoplasms] explode all trees
#2	(colorectal near/3 (neoplas* or cancer* or tumour* or tumor* or carcinoma*)):ti,ab,kw (Word variations have been searched)
#3	(colon* near/3 (neoplas* or cancer* or tumour* or tumor* or carcinoma*)):ti,ab,kw (Word variations have been searched)
#4	(bowel near/3 (neoplas* or cancer* or tumour* or tumor* or carcinoma*)):ti,ab,kw (Word variations have been searched)
#5	(rectal near/3 (neoplas* or cancer* or tumour* or tumor* or carcinoma*)):ti,ab,kw (Word variations have been searched)
#6	(rectum near/3 (neoplas* or cancer* or tumour* or tumor* or carcinoma*)):ti,ab,kw (Word variations have been searched)
#7	#1 or #2 or #3 or #4 or #5 or #6
#8	MeSH descriptor: [Carcinoembryonic Antigen] explode all trees
#9	cea:ti,ab,kw (Word variations have been searched)
#10	(carcinoembryonic near/3 antigen*):ti,ab,kw (Word variations have been searched)
#11	(carcinoembryonic near/3 antibod*):ti,ab,kw (Word variations have been searched)
#12	(carcino‐embryonic near/3 antigen*):ti,ab,kw (Word variations have been searched)
#13	(carcino‐embryonic near/3 antibod*):ti,ab,kw (Word variations have been searched)
#14	#8 or #9 or #10 or #11 or #12 or #13
#15	#7 and #14