Multi-institutional validation of a modified scheme for subcategorizing salivary gland neoplasm of uncertain malignant potential (SUMP).

BACKGROUND: The salivary gland neoplasm of uncertain malignant potential (SUMP) category in the Milan System is diagnostically challenging. This study aims to validate a modified scheme for subcategorizing SUMP in a large multi-institutional cohort. METHODS: Retrospective review of salivary gland fine-needle aspirations (FNAs) from 10 institutions were classified based on the Milan System. Cases diagnosed as SUMP with available cytology slides and surgical follow-up were retrieved for review and subcategorized based on a modified scheme as follows: basaloid SUMP (B1: absent/scant nonfibrillary matrix; B2: presence of nonfibrillary/mixed-type matrix), oncocytic/oncocytoid SUMP (O1: with mucinous background; O2: without mucinous background), and SUMP not otherwise specified (NOS). RESULTS: A total of 742 (7.5%) cases from 9938 consecutive salivary gland FNAs were classified as SUMP. Among them, 525 (70.8%) had surgical follow-up and 329 (62.7%) were available for review. The overall risk of malignancy (ROM) of SUMP was 40.4%. There were 156 cases (47.4%) subcategorized as basaloid SUMP with a ROM of 36.5%, 101 (30.7%) as oncocytic/oncocytoid SUMP with a ROM of 52.5%, and 72 (21.9%) as SUMP NOS with a ROM of 31.9%. The ROM of oncocytic/oncocytoid SUMP was significantly higher than basaloid SUMP (P = .0142) and SUMP NOS (P = .0084). No significant differences in ROM were noted between B1 and B2 (36.7% vs 36.4%, P = 1.0000) and O1 and O2 (65.2% vs 48.7%, P = .2349). CONCLUSIONS: The ROM of oncocytic/oncocytoid SUMP was 52.5% and significantly higher than that of basaloid SUMP (36.5%, P = .0142) and SUMP NOS (31.9%, P = .0084), whereas no significant differences in ROM were noted for cases with different types of extracellular matrix or background material.

An Atypical Bilateral Presentation of Fibrous Dysplasia (FD) in the Mandible: Clinical, imaging and therapeutic characterization.

INTRODUCTION AND IMPORTANCE: Fibrous Dysplasia (FD) is a benign fibro-osseous lesion, characterized by replacement with fibrous connective tissue instead of normal bone. The best treatment option for the condition has not yet been established, although several therapeutic approaches have been reported. The present case report describes the clinical, imaging and therapeutic aspects of an atypical bilateral presentation of FD in the mandible. CASE PRESENTATION: A 26-year-old afro-descendent woman, who had previously undergone surgery to remove FD in the right hemimandible, complained of asymptomatic swelling in the left hemimandible. Imaging analysis showed an ipsilateral extensive multilocular mandibular lesion, with thinning of the cortical bone. After diagnosis of FD, complete surgical removal was performed, associated with immediate local reconstruction with xenograft and covering membrane, with primary wound closure. CLINICAL DISCUSSION: Bilateral presentation of FD is uncommon, and its diagnosis by means of clinical data, imaging and histopathological analysis, is relevant in order to establish the correct therapy. CONCLUSION: Complete surgical removal associated with immediate local bone reconstruction, has shown satisfactory clinical results, when adequate follow-up is performed.