Figure3 Multivariate regression analysis of factors influencing
overall survival.
Cause of death
Fifty-one patients died as of the last follow-up date. The main causes
of death included systemic distant metastasis (18 cases, 35.3%),
including lung metastasis (9 cases), liver metastasis (5 cases), bone
metastasis (3 cases) and brain metastasis (1 case); second primary
cancer (11 cases, 21.6%), including middle and lower oesophageal
cancers (7 cases), central lung cancer (3 cases) and gastric cancer (1
case) and nontumour causes of death (9 cases, 17.6%), including
respiratory failure (3 cases) and cardiogenic death (2 cases), severe
pneumonia (1 case), asphyxia caused by sputum thrombus (1 case) and
unknown causes (2 cases). Local metastases of cervical lymph nodes were
found in 7 cases (13.7%). Local tumour recurrence was found in 6 cases
(11.8%).