Lung metastasis resection of adenoid cystic carcinoma of salivary glands.

BACKGROUND: Adenoid cystic carcinoma is a rare tumour originating from the exocrine mucous glands, known for its high propensity for distant metastases. The value of lung metastasis resection from adenoid cystic carcinoma of salivary glands origin is evaluated.
METHODS: A retrospective study was conducted on patients undergoing surgery for primary adenoid cystic carcinoma of the salivary glands between 1982 and 2006. Patients were excluded who had primary tumour macroscopic incomplete resection or were lost at follow-up. From a database of 50 eligible patients, 27 were identified as having presented a tumour recurrence during follow-up; in 20 it was first diagnosed in the form of distant metastases, and in 7 in the form of loco-regional recurrence. Nine patients who presented isolated lung recurrence underwent complete lung metastasectomy. Demographic data, pathologic characteristics and operative and postoperative record were reviewed, as well as updated survival.
RESULTS: Twenty-six men and 24 women with a median age of 57 years (range 33-79) underwent radical surgery for adenoid cystic carcinoma during the study period. In 20 patients, at a median free interval time of 3 years (range 1-12), a distant metastasis relapse was observed. Nine patients with a median free interval time of 5 years (range 1-12) underwent lung metastasectomy: five had single metastasis resection, one multiple mono-pulmonary and three multiple and bilateral. In six of these patients a new disease recurrence was noted: four patients underwent further lung metastasectomy, but in all of them progression of the disease was observed. Mean survival of the population as a whole resulted as being 16 years (SE=1.4) with an actuarial survival of 77% at 5 years, 66% at 10 years and 56% at 15 years. Mean survival of patients having presented with distant metastases resulted as being 11 years (SE=2.2). Mean survival after appearance of distant metastases resulted as being 72 months (SE=15.8) in the 9 patients treated by metastasectomy, and 62 months (SE=15.1) in the 11 who did not have metastasis resection.
CONCLUSIONS: Patients with adenoid cystic carcinoma could be frequently encountered with disease recurrence confined to the lung. The impact of complete lung metastasis resection on the course of the disease, however, is yet to be determined.