Table 3 Prognostic factors for locoregional failure in patients treated with primary surgery

Age (< 58 yrs vs. ≥ 58 yrs)

1.04 (0.54–1.99)

Tobacco use (≤ 10 PY vs. > 10 PY)

0.68 (0.34–1.34)

T stage (T1-2 vs. T3-4)

2.23 (1.07–4.62)

Pathological N stage (N0-1 vs. N2)

2.26 (1.14–4.46)

2.74 (1.17–6.41)

Contralateral LN metastasis (No vs. Yes)

2.84 (1.25–6.50)

3.24 (1.21–8.65)

Extranodal extension (No vs. Yes)

1.61 (0.82–3.14)

Lymphovascular invasion (No vs. Yes)

1.61 (0.82–3.16)

Perineural invasion (No vs. Yes)

1.06 (0.32–3.45)

Surgical margin status (Negative vs. Abutting + Positive)

1.98 (1.02–3.85)

2.36 (1.15–4.86)

Adjuvant radiotherapy (No vs. Yes)

0.38 (0.19–0.73)

0.18 (0.08–0.40)

Concurrent chemoradiotherapy (No vs. Yes)

1.77 (0.52–6.04)

Induction chemotherapy (No vs. Yes)

1.34 (0.68–2.64)