Late Recurrences Beyond Five Years in Salivary Adenoid Cystic Carcinoma: Implications for Long‐Term Surveillance

Objective Salivary adenoid cystic carcinoma (ACC) is a rare head and neck malignancy with limited surveillance guidelines. ACC disease patterns are quite variable and unpredictable. Herein, we present an institutional retrospective review of salivary adenoid cystic carcinoma and discuss patterns and predictors of recurrence. Study Design Retrospective cohort study. Setting Single Quaternary Care Referral Center. Methods We analyzed 102 adult patients with salivary gland adenoid cystic carcinoma between 1988 and 2019. Patient and tumor‐related characteristics are summarized, and recurrence, survival, and metastatic site data are described. Results Multivariable analysis showed that greater than 30% solid pathology was independently predictive of recurrence (HR 5.32, CI 2.23‐12.66). Advanced stage disease (stages III and IV) was also predictive of recurrence (HR 3.77, CI 1.57‐9.03). Nearly one‐third of all patients experienced distant recurrence. Among patients experiencing distant recurrence, 29% were diagnosed with distant recurrence more than 5 years post‐treatment. Conclusion These data support long‐term surveillance and clinical follow‐up for patients with ACC.