Growth rates over time of unoperated parotid benign tumors

The treatment of parotid benign tumor is in principle surgery, but observation may be necessary in some cases. The purpose of this study was to investigate the growth rates over time of unoperated parotid benign tumors.

We retrospectively reviewed the medical records of 63 patients with unoperated parotid benign tumors diagnosed at our institution between January 2010 and December 2022.

Forty-nine of the 63 patients had a Warthin tumor and 13 patients had a pleomorphic adenoma. On average, the unoperated parotid benign tumors grew 0.02 cm in length and 0.4 cm³ in volume per year. Compared to pleomorphic adenomas, Warthin tumors were more predominant in male patients and in those with a smoking history and a longer duration of smoking history; patients with Warthin tumors were also followed up longer (p < 0.05). However, the length and volume growth rates of unoperated Warthin tumors and pleomorphic adenomas did not significantly differ.

Surgery is the standard treatment for parotid benign tumors. However, small benign parotid tumors identified during preoperative examination can be observed through close follow-up, taking into account the patient's medical and general condition.