Impact on Medical Cost, Cumulative Survival, and Cost-Effectiveness of Adding Rituximab to First-Line Chemotherapy for Follicular Lymphoma in Elderly Patients: An Observational Cohort Study Based on SEER-Medicare

Table 1

Patient characteristics.

			First-line therapy
	Overall (N = 1,117)		Rituximab plus chemotherapy		Chemotherapy alone		𝑃 value
			(𝑛=750)		(𝑛=367)
	𝑛	% (SD)	𝑛	% (SD)	𝑛	% (SD)
Age at diagnosis (years)
66–70	327	29.3	223	29.7	104	28.3	0.94
71–75	293	26.2	197	26.3	96	26.2
76–80	285	25.5	191	25.5	94	25.6
>80	212	19.0	139	18.5	73	19.9
Gender
Male	517	46.3	355	47.3	162	44.1	0.32
Female	600	53.7	395	52.7	205	55.9
Race/ethnicity
White	1000	89.5	675	90.0	325	88.6	0.46
Nonwhite	117	10.5	75	10.0	42	11.4
Year of diagnosis
1999–2002	540	48.0	231	30.8	309	84.2	<0.0001
2003–2005	577	51.7	519	69.2	58	15.8
Stage at FL diagnosis
I	236	21.1	160	21.3	76	20.7	0.42
II	189	16.9	119	15.9	70	19.1
III	271	24.3	188	25.1	83	22.6
IV	350	31.3	240	32.0	110	30.0
Unknown	71	6.4	43	5.7	28	7.6
Histology (grade)
1	188	16.8	112	14.9	76	20.7	0.02
2	274	24.5	175	23.3	99	27.0
3	345	30.9	248	33.1	97	26.4
Not specified	310	27.8	215	28.7	95	25.9
Extranodal involvement
No	573	51.3	382	50.9	191	52.0
Yes	473	42.3	325	43.3	148	40.3	0.37
Unknown	71	6.4	43	5.7	28	7.6
Presence of “B” symptoms
No	477	42.7	348	46.4	129	35.2	<0.001
Yes	185	16.6	129	17.2	56	15.3
Unknown/Missing	455	40.8	273	36.4	182	49.6
Anemia
No	1073	96.1	719	95.8	354	96.5	0.63
Yes	44	3.9	31	4.1	13	3.5
NCI comorbidity index
0	796	71.3	546	72.8	250	68.1	0.34
1	234	20.9	146	19.5	88	24.0
≥2	87	7.8	58	7.7	29	7.9
Performance status indicators
0	955	85.5	648	86.4	307	86.7	0.22
≥1	162	14.5	102	13.6	60	32.9
Percent in census tract with some college
<25%	364	32.6	244	32.5	120	32.7	0.96
≥25%	753	67.4	506	67.5	247	67.3
Percent in census tract living in poverty
<5%	365	32.7	261	34.8	104	28.3	0.02
5–7%	151	13.5	103	13.7	48	13.1
8–12%	257	23.0	153	20.4	104	28.3
>12% or missing	344	30.8	233	31.1	111	30.3
Type of geographic area
Large metropolitan	585	52.4	396	52.8	189	51.5	0.59
Metropolitan	323	28.9	218	29.1	105	28.6
Urban	80	7.2	56	7.5	24	6.5
Less urban/rural	129	11.6	80	10.7	49	13.4