International Journal of Radiation Oncology*Biology*Physics
Clinical investigation: Head and neckMalignant parotid tumors: Presentation, clinical/pathologic prognostic factors, and treatment outcomes
Introduction
Malignant parotid tumors are an uncommon head-and-neck malignancy. The incidence of malignant salivary gland tumors in the United States is 1.2/100,000 population (1), with parotid malignancies accounting for 50–70% of these tumors 2, 3. Thus, prospective management trials for this group have not been performed. Therefore, retrospective review of patient data is required to determine the optimal treatment for these patients. The benefits from radiotherapy (RT), the most important prognostic factors, and the optimal surgery for these patients continues to be debated.
Section snippets
Methods and materials
We reviewed the charts of all patients (n = 181) diagnosed with epithelial malignant parotid tumors between 1960 and 2000 at Kansas University Medical Center (KUMC) and between 1970 and 2000 at the State University of New York Upstate Medical University (SUNY Upstate). Eighteen patients were excluded from our retrospective study. Of these, 14 were missing vital information, 3 had not received treatment, and 1 was missing RT details. Thus, 163 patients were available for analysis. To ensure
Results
As shown in Table 1, the mean patient age at diagnosis was 59.4 years (standard deviation 18); 52% of the patient population was male. The patients from KUMC comprised 56% (n = 92) of the study population, and 44% (n = 71) were diagnosed and treated at SUNY Upstate.
Nearly all patients presented with a mass (Table 1), as well as several other clinical signs and symptoms, including pain and facial weakness. Of the 163 patients, 68 (42%) had Stage I at presentation, 20 (12%) had Stage II, 3 (2%)
Discussion
Several retrospective series have detailed their treatment results and prognostic factors in patients with malignant parotid tumors, but no randomized or prospective trials have been performed. Limitations in the literature included insufficient numbers in all but a few studies using multivariate analysis to identify prognostic factors. Many studies had no staging system listed or reported on a large percentage of patients without staging and did not state whether the tumor was clinically or
Conclusion
Malignant parotid tumors have been managed during the past few decades with differing surgical and RT protocols and techniques. A number of important patient, pathologic, and treatment characteristics influence survival and local failure. Higher stage using the AJCC 5th edition criteria and increasing age are predictors of poorer local failure-free survival, cause-specific survival, and overall survival. Adjuvant RT is of value in improving locoregional control in some patients and improved
References (15)
- et al.
Malignant salivary gland tumors
Int J Radiat Oncol Biol Phys
(1986) - et al.
Prognostic variables in malignant epithelial tumors of the parotid
Int J Radiat Oncol Biol Phys
(1992) - et al.
Postoperative RT for malignant tumors of the parotid gland
Int J Radiat Oncol Biol Phys
(1997) Modified neck dissectionA study of 967 cases from 1970 to 1980
Am J Surg
(1985)- et al.
Cancer of the parotid gland
Am J Surg
(1975) - Cancer.gov (database online). National Cancer Institute; Cancer Incidence by Primary Site, US Cancer Statistics, 2000...
- et al.
Salivary gland carcinomas—Prognostic factors
Acta Oncol
(1998)