Adenoid cystic carcinoma: A retrospective clinical review

Adenoid cystic carcinoma (ACC) are uncommon tumors, representing about 10% to 15% of head and neck tumors. We compare the survival and control rates a t our institution with those reported in the literature, and examine putati ve predictors of outcome. All patients registered with the tumor registry a s having had ACC were identified. Demographic and survival variables were r etrieved from the database. Additionally, a chart review of all patients wa s done to obtain specific information. Minor gland tumors were staged using the American Joint Committee on Cancer's criteria for squamous cell carcin omas in identical sites. Histopathologic variables retrieved included grade of the tumor, margins, and perineural invasion. Treatment modalities, fiel d sizes, and radiation doses were recorded in applicable cases. An effort t o retrieve archival tumor specimens for immunohistochemical analysis was un dertaken. A total of 69 patients were treated for ACC from 1955 to 1999. On e patient, who presented with fatal brain metastasis, was excluded from fur ther analysis. Of the remaining 68 patients, 30 were men and 38 were women. The average age at diagnosis was 52 years, and mean follow-up was 13.2 yea rs. Mean survival was 7.7 years. Overall survival (OS) rates at 5, 10, and 15 years were 72%, 44%, and 34%, and cause-specific survival was 83%, 71%, and 55%, respectively. Recurrence-free survival rates were 65%, 52%, and 30 % at 5, 10, and 15 years, with a total of 29 of 68 (43%) eventually sufferi ng a recurrence. Overall survival was adversely affected by advancing T and AJCC stage. Higher tumor grades were also associated with decreased OS, al though the numbers compared were small. Primaries of the nasosinal region f ared poorly when compared with other locations. Total recurrence-free survi val, local and distant recurrence rates were distinctly better in primaries of the oral cavity/oropharynx when compared with those in other locations. Reduced distant recurrence-free survival was' significantly associated wit h increasing stage. No other variables were predictive for recurrence. Addi tionally, we found that nasosinal tumors were more likely to display higher stage at presentation, and were more often associated with perineural inva sion. Also of interest was the association of perineural invasion with marg in status, with 15 of 20 patients with positive margins displaying perineur al invasion, while only 5 of 17 with negative margins showed nerve invasion (P = 0.02). On immunohistochemistry, 2 cases of the 29 (7%) tumor specimen s found displayed HER-2/neu positivity. No correlation between clinical beh avior and positive staining could be demonstrated. Our data concur with pre vious reports on ACC in terms of survival and recurrence statistics. Stage and site of primary were important determinants of outcome. Grade may still sen e a role in decision making. We could not demonstrate any differences attributable to primary modality of therapy, perhaps due to the nonrandomiz ation of patients into the various treatment tracks and the inclusion of pa lliative cases. Similarly, perineural invasion, radiation dose and field si ze, and HER-Z/neu positivity did not prove to be important factors in our e xperience. (C) 2001 Wiley-Liss, Inc.