Definitive radiotherapy or chemoradiotherapy for distal rectal cancer with early stage of cT1-2N0

Figures & data

Table 1 Patient demographics, baseline tumor characteristics

Variable	Number	Percent
Age, years
≥56	114	49.4%
<56	117	50.6%
Gender
Male	129	55.8%
Female	102	44.2%
Hb g/L
≥129	112	48.5%
<129	119	51.5%
CEA ug/mL
Normal	113	48.9%
Elevated	118	51.1%
c T stage
T1	67	29.0%
T2	164	71.0%
Tumor grade
G1	19	8.2%
G2	172	74.5%
G3	40	17.3%
Prescription dose
≥60	107	46.3%
<60	124	53.7%
Concurrent chemotherapy
Folfox6	27	11.7%
Xelox	82	35.5%
Xeloda	11	4.8%
None	111	48.0%

Abbreviations: Hb, hemoglobin; CEA, carcinoembryonic antigen; G1, well differentiated; G2, moderately differentiated; G3, poorly differentiated.

Table 2 Short-term efficacy

Group	cCR	Non-cCR
Whole group (n=231)	135 (58.4%)	96 (41.6%)
T1 subgroup (n=67)	51 (76.1%)	16 (23.9%)
T2 subgroup (n=164)	84 (51.2%)	80 (48.8%)

Abbreviation: cCR, clinical complete response.

Table 3 Univariate and multivariate analyses of cCR for the whole group

Variables	Univariate analysis		Multivariate analysis
HR (95% CI)	p-Value	HR (95% CI)	p-Value
T stage (T2 vs T1)	2.305 (1.259–4.220)	0.007	3.036 (1.576–5.850)	0.001
Concurrent chemotherapy (yes vs no)	1.859 (1.094–3.157)	0.022	2.434 (1.204–4.921)	0.013
Radiation dose (<60 vs ≥60)	0.564 (0.332–0.957)	0.034	0.473 (0.232–0.963)	0.039
Age (<56 vs >56)	1.514 (0.894–2.563)	0.123	1.539 (0.881–2.687)	0.130
Gender (male vs female)	1.171 (0.692–1.982)	0.556	1.163 (0.643–2.103)	0.618
Hb level, g/L (<129 vs ≥129)	0.750 (0.437–1.288)	0.297	0.573 (0.320–1.023)	0.060

Abbreviations: CI, confidence interval; HR, hazard ratio; CR, complete response; Hb, hemoglobin.

Table 4 Long-term survival

Group	cCR group		Non-cCR group		P-value
3 years	5 years	3 years	5 years
OS	94.01%	90.85%	93.75%	80.00%	0.007^#
PFS	92.59%	90.52%	86.43%	73.57%	0.002^#
LR	3.00%	3.00%	8.40%	13.60%	0.006^#

Note: ^#calculated by the Kaplan–Meier method.

Abbreviations: OS, overall survival; PFS, progression-free survival; LR, local recurrence.

Table 5 Univariate and multivariate analysis of PFS for the whole group

Variables	Univariate analysis		Multivariate analysis
HR (95% CI)	p-Value	HR (95% CI)	p-Value
T stage (T2 vs T1)	2.836 (1.411–5.699)	0.003	2.671 (1.330–5.363)	0.006
CEA, µg/mL (≥5.00 vs <5.0)	2.343 (1.199–4.576)	0.013	3.685 (1.868–7.271)	<0.001
Concurrent chemotherapy (yes vs no)	0.432 (0.212–0.882)	0.021	0.463 (0.250–0.857)	0.014
Radiation dose (<60 vs ≥60)	1.701 (0.846–3.419)	0.136	–
Age (<56 vs >56)	0.577 (0.291–1.146)	0.116	–
Gender (male vs female)	0.902 (0.462–1.762)	0.762	–
Hb level, g/L (<129 vs ≥129)	1.363 (0.668–2.784)	0.395	–

Abbreviations: CEA, carcinoembryonic antigen; Hb, hemoglobin; PFS, progression-free survival; CI, confidence interval; HR, hazard ratio.

Figure 1 Overall survival (OS) for the whole group.

Figure 2 Progression-free survival (PFS) for the whole group.

Figure 3 The comparison of overall survival (OS) between clinical complete response (cCR) and non-cCR patients. Patients with cCR acquired better OS than those with non cCR (p=0.007).

Figure 4 The comparison of progression-free survival (PFS) between clinical complete response (cCR) and non-cCR patients. Patients with cCR acquired better progression-free survival (PFS) than those with non cCR (p=0.002).

Table 6 Univariate and multivariate analysis of LRFS for the whole group

Variables	Univariate analysis		Multivariate analysis
HR (95% CI)	p-Value	HR (95% CI)	p-Value
T stage (T2 vs T1)	1.553 (0.686–3.516)	0.291	–
CEA, ug/mL (≥5.00 vs <5.0)	2.839 (1.295–6.221)	0.009	5.861 (1.723–19.943)	0.005
Concurrent chemotherapy (yes vs no)	0.367 (0.153–0.879)	0.025	0.267 (0.098–0.730)	0.010
Radiation dose (<60 vs ≥60)	2.215 (1.155–4.218)	0.035	2.838 (1.098–7.338)	0.031
Age (<56 vs >56)	0.923 (0.421–2.023)	0.841	–
Gender (male vs female)	1.057 (0.478–2.329)	0.891	–
Hb level, g/L (<129 vs ≥129)	1.542 (0.657–3.770)	0.309	–

Abbreviations: CEA, carcinoembryonic antigen; Hb, hemoglobin; LRFS, local recurrence-free survival; CI, confidence interval; HR, hazard ratio.

Table 7 Univariate and multivariate analysis of DMFS the whole group

Variables	Univariate analysis		Multivariate analysis
HR (95% CI)	p-Value	HR (95% CI)	p-Value
T stage (T2 vs T1)	4.274 (1.378–13.253)	0.002	2.431 (1.876–5.335)	0.018
CEA, µg/mL (≥5.00 vs <5.0)	2.204 (1.466–3.964)	0.037	2.286 (1.076–4.858)	0.032
Concurrent chemotherapy (yes vs no)	0.579 (0.210–1.593)	0.290	–
Radiation dose (<60 vs ≥60)	1.947 (0.676–5.606)	0.217	–
Age (<56 vs >56)	0.320 (0.103–0.993)	0.049	–
Gender (male vs female)	1.064 (0.396–2.857)	0.902	–
Hb level, g/L (<129 vs ≥129)	1.376 (0.478–3.962)	0.554	–

Abbreviations: CEA, carcinoembryonic antigen; Hb, hemoglobin; DMFS, distant metastasis-free survival; CI, confidence interval; HR, hazard ratio.

Table 8 Treatment toxicity

Toxicity type	Grade
Acute toxicity	1~2	3	4	5	≥3
Abdominal pain	84 (36.4%)	6 (2.6%)	0	0	6 (2.6%)
Nausea	59 (25.5%)	9 (3.9%)	0	0	9 (3.9%)
Vomiting	51 (22.1%)	8 (3.5%)	0	0	8 (3.5%)
Diarrhea	92 (39.8%)	33 (14.3%)	7 (3.0%)	0	40 (17.3%)
Radiodermatitis	122 (52.8%)	12 (5.2%)	0	0	12 (5.2%)
Neurotoxity	25 (10.8%)	7 (3.0%)	0	0	7 (3.0%)
Hand–foot syndrome	45 (19.5%)	4 (1.7%)	NA	NA	4 (1.7%)
Hemoglobin	42 (18.2%)	3 (1.3%)	0	0	3 (1.3%)
Neutrophils	108 (46.8%)	13 (5.6%)	0	0	13 (5.6%)
Platelets	32 (13.9%)	5 (2.2%)	0	0	5 (2.2%)
Late toxicity
Anal stenosis	49 (21.2%)	6 (2.5%)	0	0	6 (2.5%)
Anal ulcer	42 (18.2%)	3 (1.3%)	2 (0.8%)	0	5 (2.2%)
Anal/rectal bleeding	46 (19.9%)	6 (2.5%)	0	0	6 (2.5%)

Abbreviations: CEA, carcinoembryonic antigen; Hb, hemoglobin; DMFS, distant metastasis-free survival; CI, confidence interval; HR, hazard ratio; NA, not applicable.