Table 2. Cumulative risk of recurrence by patient and disease characteristics at 3 years' follow-up among patients with laryngeal squamous cell carcinoma.

	n	3-year risk	95% Confidence interval
Overall	326	20.5	18.6	22.5
Sex
Male	283	20.5	18.4	22.6
Female	42	20.8	15.5	26.5
Smoking
Ever	295	21.1	19.0	23.3
Never	22	24.3	16.2	33.4
Unknown	9	12.0	6.2	20.0
Alcohol
Ever	57	26.3	20.7	32.2
Unknown	77	17.1	13.8	20.7
Age (years)
0–59	114	25.2	21.3	29.3
60–69	121	22.7	19.2	26.3
70+	91	15.1	12.3	18.1
Subsite
Glottic	208	18.7	16.5	21.1
Supraglottic	107	25.1	21.0	29.3
Subglottic	11	21.7	11.6	33.8
T-status
T1	72	11.0	8.8	13.6
T2	104	27.3	22.9	31.9
T3	81	35.8	29.6	42.1
T4	69	21.1	16.9	25.7
N-status
N0	260	19.7	17.6	21.9
N1	23	23.4	15.6	32.1
N2+	43	25.5	19.2	32.3
Stage
Early stage	161	16.7	14.4	19.1
Advanced stage	165	26.6	23.2	30.1
Stage I-IV
I	69	10.9	8.6	13.4
II	92	28.2	23.4	33.1
III	73	33.6	27.4	39.9
IV	92	22.6	18.7	26.8
Treatment modality
Radiotherapy	238	23.8	21.2	26.5
Transoral lasermicrosurgery	31	9.6	6.7	13.1
Total laryngectomy	39	21.9	16.2	28.3
Chemo-radiotherapy	18	36.6	23.4	49.9
Period of treatment
1983–1989	103	25.6	21.5	30.0
1990–1996	75	19.9	16.0	24.1
1997–2003	80	19.9	16.2	23.9
2004–2010	68	16.8	13.3	20.7