Occult Malignancy in Adult Tonsillectomy for Benign Indication

Objective: National pathology guidelines recommend full pathologic analysis for all adult tonsillectomy specimens. We evaluated the available data on occult malignancy in adult tonsillectomy for benign indication, and created a screening system to reduce the risk of missed malignancies if routine histopathologic examination were to be discontinued. Study design: Retrospective chart review and systematic review of the literature. Setting: Tertiary care academic hospital and multi-hospital private healthcare system. Subjects and methods: A systematic literature review identified case series of adult tonsillectomy. Retrospective chart review at our institutions from 2000 to 2016 produced an additional case series. The pooled rate of occult malignancy was determined, and re-analyzed using criteria based on preoperative risk factors designed to identify patients requiring full pathologic analysis. The predicted effects of prospective application of the proposed criteria were calculated. Pooled occult malignancy prevalence was estimated. Results: Literature review and our own case series yielded 12,094 total cases. Occult malignancy prevalence in the combined data was 0.033%, representing four occult malignancies. Three out of the four would have been selected for full pathology preoperatively with use of the proposed criteria. Statistical analysis indicates that the predicted frequency of occult malignancy incidence in cases negative for the criteria is 0.01%, or 1/10,000. Conclusion: Application of the proposed criteria to adults undergoing tonsillectomy for benign indication identifies a subset of patients with an estimated incidence of occult malignancy similar to that reported for pediatric tonsillectomy, and potentially may permit safe elimination of pathologic analysis of their tonsil specimens. Level of Evidence: Pooled analysis of case series from the literature and a single institution, level 4.