Carcinoma ex pleomorphic adenoma of the parotid gland. Study and implications for diagnostics and therapy.

BACKGROUND: Carcinoma ex pleomorphic adenoma (CXPA) is a rare parotid malignancy and until today no standardized concept exists for its therapy apart from recommendations for parotid carcinoma in general. Prognosis is thought to be poorer than for other parotid malignancies. We sought to describe a general diagnostic and therapy strategy and assess factors predicting the outcome.

METHODS: We retrospectively analysed the courses of 22 patients with a CXPA of the parotid gland treated at a tertiary medical care centre for otorhinolaryngology. We examined parameters of medical history, diagnostics, surgical and adjunctive therapy and analysed overall and disease-specific survival.

RESULTS: About half of the patients had evidence of a parotid mass of up to 1 year only while maximum of the others was 48 years. Nine patients were primarily operated without suspicion for malignancy. Both 5-year disease-specific and overall survival were 60%. Recurrence-free survival rate after 5 years was 85%. Any patients with a stage I or II disease had an uneventful follow-up. To date, no patient with a stage IV disease has survived longer than 5 years.

CONCLUSION: Surgical therapy (total or radical parotidectomy) is the method of choice for CXPA of the parotid gland. Stage I tumors have a very good and stage IV tumors a bad prognosis.