Cancer of the parotid gland; long-term follow-up. A single centre experience on recurrence and survival.

BACKGROUND: The aim of the study was to investigate the results of treatment of malignant parotid gland tumours at a single centre during a 56 year period, focusing on tumour control and survival. PATIENTS AND METHODS: At Uppsala University Hospital, Sweden, 144 patients (73 male and 71 female) with parotid cancer were treated between 1948 and 2004. The mean and median ages were 62 and 65 years, respectively (range 16-89 years). Surgery was the primary treatment in 113 (78%) patients followed by radiotherapy in 81. Postoperative radiotherapy in doses of 64-66 Gy, where the intention was curative and delivered with either split course or not, was administered to a majority of patients after 1970. The split-course mode was practised between 1970 and 1989. The median follow-up time was 8.3 years for patients still alive. There were 57 (40%) relapses, of which 40 were local recurrences with 26 inside the treatment volume.
RESULTS: The overall 5-year survival was 53%. The majority of tumour-related deaths appeared in the first 3-5 years after diagnosis. Age, co-morbidity, the presence of lymph node metastases, adenoid cystic carcinoma and extent of disease were important for outcome; gender, however, was not. We found no difference in the survival between patients following split course therapy versus continuous fractionation. No difference could be seen in the survival of patients treated in the 1970s versus the 1990s.
CONCLUSIONS: Age, nodal engagement, a higher T-stage, adenoid cystic carcinoma histopathology, facial palsy and intercurrent disease worsen the outcome of patients, whereas gender does not. Treatment principles at our hospital have been surgery followed by radiotherapy since the early 1970s even though a split course technique was practised during a part of this period. Survival has not improved markedly. Thus, there is scope for improvement for this group of patients.