Salivary adenoid cystic carcinoma in Denmark 1990–2005: Outcome and independent prognostic factors including the benefit of radiotherapy. Results of the Danish Head and Neck Cancer Group (DAHANCA)

•A national Danish study presenting 201 patients with adenoid cystic carcinoma.•10-year disease specific survival was 75%.•36% experienced recurrence during follow-up (median 7.5 years).•The treatment of choice is surgery with free margins.•Adjuvant radiotherapy should be considered in selected patients.

SummaryAimTo describe outcome and prognostic factors, including the effect of radiotherapy, in a consecutive national series of salivary gland adenoid cystic carcinomas.MethodsFrom the national Danish salivary gland carcinoma database in the structure of DAHANCA, 201 patients diagnosed with adenoid cystic carcinoma, and treated with a curative intent, were identified in the period between 1990 and 2005. Variables necessary for statistical analyses were extracted from the database.ResultsThe 10-year crude survival and disease specific survival rates were 58% and 75%, respectively. The 10-year locoregional control rate was 70%, and 36% of patients experienced a recurrence during follow-up (median 7.5 years); 18% developed distant metastases (most commonly to the lungs). In multivariate analysis, stage and margin status were both important factors with regards to survival and locoregional control. Radiotherapy did not improve survival, but it did improve the locoregional control rate.ConclusionsThe treatment of choice is surgery with as wide margins as possible including elective, selective neck dissection. Adjuvant radiotherapy should be considered in patients with incomplete tumor resection, high disease stages, and tumors with a solid growth pattern.