OBJECTIVETo study the clinical characters, the outcomes of treatments and the factors affecting long-term treatment results of adenoid cystic carcinoma (ACC) of the maxillary sinus.

METHODSThe clinical data of 80 patients with ACC of the maxillary sinus treated initially were analyzed retrospectively. Survival rate, local recurrence and distant metastasis were analyzed using Kaplan-Meier method. Prognosis factors were analyzed by Log-rank test and Cox regression.

RESULTSThe 5-, 10- and 15-year cumulative overall survival rates were 65.2%, 37.1%, 26.3% respectively and 5-, 10-, and 15-year disease-free survival rates 50.7%, 30.7% and 24.5% respectively. The 5-, 10- and 15-year cumulative local control rates were 68.5%, 47.3% and 47.3% respectively and the cumulative distant metastasis rate were 32.8%, 48.8% and 48.8% respectively. Prognostic factors affecting survival included T stage, pathologic grade and the modes of treatment (P < 0.05). Patients with combined therapy composed of surgery and radiation had a better local control, compared with surgery or radiation alone (χ(2) = 18.33, P < 0.01), and surgery combined with postoperative radiation was prior to preoperative radiation combined with surgery (χ(2) = 6.64, P < 0.05). Patients treated with surgery combined with preoperative radiation, either with doses of ≥ 60 Gy or with negative margins, had a better local control, compared with doses < 60 Gy and with positive margins (χ(2) = 5.06, P < 0.05). The most of patients (62.8%) died of local recurrence.

CONCLUSIONSThe most of failure was due to recurrence. Combined therapy composed of surgery and radiation improves the local control and survival in patients with ACC of the maxillary sinus, compared with surgery or radiation alone. Surgery combined with postoperative radiation provides the best overall survival and local control and should be the first choice of treatments.