Clinical Features Analysis and Survival Nomogram of Primary Small Intestinal Diffuse Large B-Cell Lymphoma

Figures & data

Table 1 Clinical Features of All Primary Small Intestinal Diffuse Large B-Cell Lymphoma

Characteristics	Training Set	Internal Validation Set	External Validation Set	P value
N	817	327	24	–
Year of diagnosis, n (%)				<0.001
2004–2009	419 (51.3)	156 (47.7)	0 (0.0)
2010–2016	398 (48.7)	171 (52.3)	7 (29.2)
2017–2021	0 (0.0)	0 (0.0)	17 (70.8)
Age (years)	64.5±16.3	65.9±16.4	60.3±14.1	0.165
≥60	528 (64.6)	216 (66.1)	13 (54.2)
<60	289 (35.4)	111 (33.9)	11 (45.8)
Sex, male, n (%)	509 (62.3)	204 (62.4)	14 (58.3)	0.923
Race, n (%)				<0.001
White	675 (82.6)	283 (86.5)	0 (0.0)
Black	42 (5.1)	17 (5.2)	0 (0.0)
Others	100 (12.2)	27 (8.3)	24 (100.0)
Insurance, n (%)				0.220
Yes	570 (69.8)	245 (74.9)	17 (70.8)
No/unknown	247 (30.2)	82 (25.1)	7 (29.2)
Marital status at diagnosis, n (%)				<0.001
Married	462 (56.5)	178 (54.4)	23 (95.8)
Unmarried	355 (43.5)	149 (45.6)	1 (4.2)
Ann Arbor stage, n (%)				<0.001
Stage I/II	603 (73.8)	239 (73.1)	8 (33.3)
Stage III/IV	214 (26.2)	88 (26.9)	16 (66.7)
Surgery for primary site, n (%)				0.916
Yes	541 (66.2)	218 (66.7)	15 (62.5)
No/unknown	276 (33.8)	109 (33.3)	9 (37.5)
Radiotherapy, n (%)				0.034
Yes	46 (5.6)	14 (4.3)	4 (16.7)
No/unknown	771 (94.4)	313 (95.7)	20 (83.3)
Chemotherapy, n (%)				0.159
Yes	534 (65.4)	228 (69.7)	19 (79.2)
No/unknown	283 (34.6)	99 (30.3)	5 (20.8)
Survival months median (IQR)	28.0 (4.0, 83.0)	26.0 (4.0, 67.0)	39.5 (13.8, 51.8)	0.182
All-cause mortality, n (%)	386 (47.2)	145 (44.3)	7 (29.2)	0.165

Table 2 Univariate and Multivariate Analyses of Factors Associated with OS in Training Set

	Univariate Analysis		Multivariate Analysis
	HR (95% CI)	P	HR (95% CI)	P
Age (years)
≥60	2.54 (1.99–3.24)	<0.001	2.24 (1.76–2.87)	<0.001
<60	Ref.	–	Ref.	–
Sex, male	0.99 (0.81–1.22)	0.934
Race
White	1.13 (0.82–1.56)	0.463
Black	1.28 (0.77–2.15)	0.345
Others	Ref.	–
Insurance
Yes	1.06 (0.86–1.32)	0.577
No/unknown	Ref.	–
Marital status at diagnosis
Married	0.70 (0.57–0.80)	<0.001	0.70 (0.58–0.86)	0.001
Unmarried	Ref.	–	Ref.	–
Ann Arbor stage
Stage I/II	Ref.	–	Ref.	–
Stage III/IV	2.07 (1.68–2.54)	<0.001	2.50 (2.01–3.10)	<0.001
Surgery for primary site
Yes	0.72 (0.58–0.89)	0.003	0.71 (0.57–0.88)	0.002
No/unknown	Ref.	–	Ref.	–
Chemotherapy
Yes	0.39 (0.32–0.48)	<0.001	0.36 (0.29–0.45)	<0.001
No/unknown	Ref.	–	Ref.	–
Radiotherapy
Yes	0.85 (0.54–1.35)	0.483
No/unknown	Ref.	–

Figure 1 A survival nomogram for predicting 1-year, 3-year and 5-year survival rates of primary small intestinal diffuse large B-cell lymphoma patients.

Figure 2 Decision curves analysis (DCA) for the survival nomogram to predict OS. (A) The DCA of nomogram for OS in training cohort; (B) the DCA of nomogram for OS in internal validation cohort; (C) the DCA of the survival nomogram for OS in external validation cohort.

Figure 3 The predictive performances of the survival nomogram for predicting 1-year, 3-year and 5-year OS in PsI-DLBCL. ROC curves displayed that this survival nomogram discriminated well in training set (A), internal validation set (B) and external validation set (C).

Figure 4 The calibration curves for predicting OS in PsI-DLBCL patients. (A–C) Calibration plots of 1-year, 3-year and 5-year mortality in training cohort; (D–F) calibration plots of 1-year, 3-year and 5-year mortality in internal validation cohort; (G–I) calibration plots of 1-year, 3-year and 5-year mortality in external validation cohort. Nomogram-predicted probabilities of OS were plotted on the x-axis, actual observed outcomes were plotted on the y-axis.

Figure 5 Kaplan–Meier curves of the high-risk and low-risk group of PsI-DLBCL patients stratified by the survival nomogram predicted probabilities in training set (A). internal validation set (B) and external validation set (C).