Salivary Clear Cell Carcinoma Clinicopathologic Characteristics and Outcomes: A Population-Based Analysis

Abstract

Background: Salivary clear cell carcinoma is an uncommon, low-grade malignancy for which limited data describing predictive clinicopathologic factors and treatment outcomes exist because of rarity. Methods: The authors queried the Surveillance, Epidemiology, and End Results database from 1982 to 2014. Multivariate Cox and Kaplan-Meier analyses were performed to determine disease-specific survival (DSS) and predictive clinicopathologic factors. Results: One hundred ninety-eight patients with salivary clear cell carcinoma were included. Overall incidence was 0.011 per 100 000 individuals, with no significant annual percentage change across years (−0.93%, P = .632). Five-, 10-, and 20-year DSS rates were 81.3% (n = 117), 69.6% (n = 94), and 55.3% (n = 68), respectively. Men (hazard ratio, 4.74; P = .0087) and patients with regional (hazard ratio, 5.59; P = .018) or distant (hazard ratio, 8.9; P = .01) metastases carried a worse prognosis. Five-year DSS was greater in patients with localized disease (96.36%, P < .0001) than those with regional or distant metastases. Treatment with surgery alone had better 10-year DSS (86.3%) compared with treatment with combination radiation and surgery (57.6%) or radiation monotherapy (18.75%, P < .0001). Conclusions: Salivary clear cell carcinoma carries an overall good prognosis. Patients with localized disease and those treated with surgery alone have more favorable prognoses. Male patients and those with regional or distant metastatic disease at time of presentation carry a worse prognosis. Level of Evidence: N/A