Factors associated with acute and late dysphagia in the DAHANCA 6 & 7 randomized trial with accelerated radiotherapy for head and neck cancer

Figures & data

Table I. Patient and treatment characteristics.

	Number of patients (%)
Protocol
DAHANCA 6	684 (47%)
DAHANCA 7	777 (53%)
Fractions per week
5 fx per week	716 (49%)
6 fx per week	745 (51%)
Median (range) age (years)	62 (20–88)
Sex
Male	1216 (83%)
Female	245 (17%)
Primary site
Glotttic	691 (47%)
Supraglottic	210 (14%)
Pharynx	428 (30%)
Cavum oris	131 (9%)
T-classification
T1–2	999 (68%)
T3–4	462 (32%)
Nodal classification
Node negative	427 (30%)
Node positive	1034 (70%)
Tumor stage
I	424 (29%)
II	362 (25%)
III	304 (21%)
IV	371 (25%)
Performance status
0	828 (76%)
1–2	256 (24%)
Baseline dysphagia
Grade 0–1	696 (85%)
Grade 2–4	120 (15%)

Figure 1. Prevalence of severe dysphagia over time.

Table II. Univariate analysis of risk factors.

Variable	Severe acute dysphagia		Severe late dysphagia
	Number of patients	P-value	Number of patients	P-value
Age
< 62 years	330 (45%)		119 (20%)
≥ 62 years	283 (39%)	0.048	75 (12%)	0.001
Sex
Female	146 (59%)		46 (24%)
Male	467 (38%)	< 0.0001	148 (15%)	0.001
Site
glottic laryngeal cancer	116 (17%)		19 (3%)
non-glottic cancer	497 (64%)	< 0.0001	175 (30%)	< 0.0001
T-classification
T1–T2	332 (33%)		85 (10%)
T3–T4	281 (61%)	< 0.0001	109 (34%)	< 0.0001
N-classification
N0	324 (31%)		97 (11%)
N1–3	289 (67%)	< 0.0001	97 (33%)	< 0.0001
Clinical stage
St 0–2	199 (25%)		46 (6%)
St 3–4	413 (61%)	< 0.0001	148 (31%)	< 0.0001
Baseline dysphagia (DAHANCA)
grade 0–1	254 (36%)		94 (16%)
grade 2–4	91 (76%)	< 0.0001	39 (50%)	< 0.0001
Fraction per week
5 fx per week	278 (38%)		100 (16%)
6 fx per week	335 (46%)	0.001	94 (16%)	ns

Absolute number of patients with severe dysphagia (proportions in brackets).

Table III. Multivariate analysis of risk factors for severe acute and late dysphagia. Odds ratios (OR), 95% confidence intervals (95% CI) and p-values.

Variable	Acute dysphagia			Late dysphagia
	OR	95% CI	P-value	OR	95% CI	P-value
Age
< 62 years	1.00			1.00
≥ 62 years	1.45	1.02–2.05	0.037	1.05	0.68–1.64	ns
Gender
Female	1.00			1.00
Male	1.37	0.89–2.11	ns	1.02	0.61–1.73	ns
Site
glottic laryngeal cancer	1.00			1.00
non-glottic cancer	6.46	4.22–9.40	< 0.0001	6.97	3.59–13.50	< 0.0001
T-classification
T0–T2	1.00			1.00
T3–T4	1.54	1.06–2.24	0.025	2.01	1.28–3.16	0.002
N-classification
N0	1.00			1.00
N1–3	1.99	1.33–2.97	0.001	1.62	1.02–2.59	0.043
Baseline dysphagia (DAHANCA)
grade 0–1	1.00			1.00
grade 2–4	2.1	1.26–3.49	0.004	2.29	1.32–3.98	0.003
Fraction per week
5 fx per week	1.00			1.00
6 fx per week	1.82	1.30–2.56	0.001	0.77	0.50–1.18	ns

Table IV. Multivariate analysis of risk factors for severe acute and late dysphagia using backward selection. Odds ratios (OR), 95% confidence intervals (95% CI) and p-values.

Variable	Acute dysphagia			Late dysphagia
	OR	95% CI	P-value	OR	95% CI	P-value
Age
< 62 years	1.00
≥ 62 years	1.45	1.02–2.05	0.037
Site
glottic laryngeal cancer	1.00			1.00
non-glottic cancer	6.83	4.49–10.39	< 0.0001	6.92	3.63–13.20	< 0.0001
T-classification
T0–T2	1.00			1.00
T3–T4	1.56	1.07–2.26	0.021	2.05	1.30–3.21	0.002
N-classification
N0	1.00			1.00
N1–3	1.93	1.29–2.87	0.001	1.64	1.03–2.60	0.036
Baseline dysphagia (DAHANCA)
grade 0–1	1.00			1.00
grade 2–4	2.12	1.27–3.52	0.004	2.22	1.28–3.84	0.004
Fraction per week
5 fx per week	1.00
6 fx per week	1.82	1.30–2.56	0.001