Prognostic value of changes in serum carcinoembryonic antigen levels for preoperative chemoradiotherapy response in locally advanced rectal cancer

Table 1 Predictive factor for response of preoperative chemoradiation therapy for rectal cancer in the literature

Ref.	Study design	pCR (%)	Related factor with response of preoperative CRT	Independent factor for pCR
Restivo et al[7], 2013	Prospective (n = 260)	16.5%		CEA < 5 ng/mL and distance from anal verge > 5 cm
Huh et al[8], 2013	Retrospective (n = 391)	14.6%	Noncircumferential tumors, nonmacroscopic ulceration, WELL differentiation, Early T, N stage, low level of pretreatment CEA	Tumor circumferentiality, macroscopic ulceration, pretreatment CEA < 5 ng/mL
Wallin et al[9], 2013	Retrospective (n = 469)	20.0%		Pretreatment CEA ≤ 5 ng/mL
Kleiman et al[10], 2015	Prospective (n = 141)	13.5%		Low post CRT CEA level, normalization of CEA from initial elevated; CEA level
Hu et al[11], 2018	Prospective (n = 146)	15.0%	CEA exponential decrease group between pretreatment and during-CRT: Higher rates of downstaging and pCR	CEA clearance pattern
Yamamoto et al[12], 2019	Prospective (n = 111)		Combination of lymphocyte to monocyte ratio (LMR) and ypN; status: poor prognosis	Low pretreatment LMR ypN(+)

pCR: Pathologic complete response; CEA: Carcinoembryonic antigen; CRT: Chemoradiation treatment.