Adenoid cystic carcinoma in head and neck

Objective: To analyze adenoid cystic carcinoma (ACC) in head and neck region with respect to age, sex, site of origin, histological type, role of Fine Needle Aspiration Cytology (FNAC) in diagnosis, metastasis, various treatment modalities and their effectiveness in local control of disease. Design: A descriptive study. Place and Duration of Study: Department of Otolaryngology and Head and Neck Surgery, Pakistan Institute of Medical Sciences, Islamabad from January, 1988 to December 1998. Patients and Methods: Case histories of 26 patients with histologically proven ACC in the head and neck region were selected from the departmental record. Clinical data included age and sex of patient, tumor location, presenting symptoms FNAC reports, predominant histological pattern of tumor, tumor stage, treatment modality, tumor recurrences and metastasis and final clinical status. Results: Among 26 cases, there were 16 males and 10 females. The mean age was 52 years (Range 30-75 years). In 57.7% patients, tumor was located in minor salivary glands whereas in 42.3% , major salivary glands were the site of origin. Plate was the commonest site of origin. FNAC reports showed ACC in 76.9% patients. In 80.8% patients, histopathological reports clearly mentioned the predominant histological type of ACC. Histological pattern was 66.6% cribriform, 23.8% tubular and 9.5% were of solid pattern, Regional lymph node metastasis was found in only 7.6%. Distant metastasis developed in 11.5%, whereas 69.2% patients were treated by surgery followed by postoperative radiotherapy, only 11.1% develop recurrence at the primary site. Radiotherapy was given to only one patient (3.8%), who was alive with disease at the time of last follow up. Conclusion: The peak age incidence of ACC in head and neck region was in 5th decade with slight male preponderance. Tumor was more common in minor salivary glands and palate was the commonest site of origin. FNAC was helpful in diagnosis of ACC in majority of cases. Cribriform subtype was the commonest histological pattern. ACC had very low regional lymph node metastasis. Lung was the commonest site of distant metastasis. surgical excision followed by radiotherapy was the best treatment modality for achieving local control on disease. (author)