Primary squamous cell carcinoma of the parotid gland

To investigate the clinical behavior and treatment outcome of patients with primary squamous cell carcinoma (SCC) of the parotid gland.

Twelve cases of primary SCC originating in the parotid gland were retrospectively reviewed. The majority of patients had a locally advanced disease. Eight cases underwent a combination of radical surgery and postoperative radiotherapy, whereas the remaining four cases were treated with radiotherapy alone. Patterns of treatment failure, survival rate, and prognostic factors for these patients were investigated.

The predominant pattern of failure was local failure, either alone or in combination with other failures. Two patients who were treated with radiation alone had persistent disease after completion of treatment, whereas 4 of 8 patients who received combined modality treatment and 2 of 4 patients who were treated with radiation alone subsequently developed local recurrences in the primary site or surgical bed. The local failure rate and regional failure rate were 58% and 25%, respectively. Most locoregional recurrences developed within 1 year after initial treatment. Only 2 patients had distant metastasis. The prognosis appeared to be relatively poor for those patients, compared with those with SCC in other head and neck sites. The overall 5-year actuarial survival rate and the disease-free survival rate were 31% and 33%, respectively. Although advanced stage, facial nerve palsy, and regional lymph node metastasis all portended an unfavorable prognosis, only patient age and treatment modality were found to be statistically significant poor prognostic factors.

Primary SCC of the parotid gland is an uncommon tumor with a highly malignant potential. Our results indicate that a combination of radical surgery and postoperative radiotherapy is the treatment of choice for achieving better locoregional control rates and improved cure rates in the treatment of these patients.