Patients with head and neck squamous cell carcinoma (HNSCC) are at an elevated risk of developing second primary malignancies (SPM). Our objectives were to estimate the excess risk of oesophageal and gastric SPMs in patients with malignancies of the pharynx or larynx and, additionally, to examine possible risk factors of developing SPMs.
Data on all patients treated for HNSCC with curative intent in the Region of Southern Denmark in the period between 1 January 2000 and 31 December 2010 were reviewed. A total of 1,172 patients were identified. The combined data from the DAHANCA database, the Danish National Pathology Registry and the patient charts were analysed.
A total of 27 patients developed an SPM in the oesophagus or stomach corresponding to a standardised incidence ratio of 9.5 (95% confidence interval (CI): 6.5-13.9). Supraglottic (odds ratio (OR) = 6.9; p