Intraoperative Capsular Exposure in Benign Superficial Lobe Parotid Tumors: Histopathological Findings and Long-Term Outcomes

Capsular exposure is frequently encountered during surgery for benign superficial lobe parotid tumors, especially at the superficial-deep lobe interface, where the tumor may closely abut the facial nerve. However, whether this finding reflects occult neoplastic involvement of adjacent deep lobe tissue remains unclear. This prospective cohort study evaluated the histopathological status of deep lobe tissue sampled from areas of intraoperative capsular exposure or corresponding deep lobe projections in patients undergoing partial superficial parotidectomy. To our knowledge, this is the first prospective study to obtain tissue-level evidence directly at sites of intraoperative capsular exposure rather than inferring risk from recurrence rates. Seventy-seven patients with benign superficial lobe parotid tumors were included. Capsular exposure was observed in 48 patients, whereas 29 had no intraoperative capsular exposure. Warthin tumor and pleomorphic adenoma were the predominant histological subtypes, accounting for 51.9% and 40.3% of cases, respectively. Tumors with capsular exposure were significantly larger than those without exposure. No neoplastic involvement was identified in any sampled deep lobe specimen. Among pleomorphic adenoma cases, no capsular discontinuities or satellite nodules were observed. During a mean follow-up of 7.8 years, no symptomatic recurrence was documented. These findings provide histopathological evidence that focal capsular exposure is not necessarily associated with occult deep lobe involvement. In selected benign superficial lobe parotid tumors, capsular exposure alone may therefore not justify extending the resection when capsular integrity is preserved, and tumor spillage is avoided.