Neoplasm

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. Cancer

Section: Discussionmentioning

confidence: 99%

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

Hang

Lee

Nga

et al. 2022

“…Some have illustrated a simple scheme by separating these into 2 groups as basaloid neoplasm and salivary gland neoplasm with predominant oncocytic cells, whereas others have developed a more sophisticated approach that takes into consideration cell type (basaloid or oncocytoid), variation of nuclear size (pleomorphic or monomorphic), stroma (fibrillary, hyaline, or mixed), background materials (cystic, mucinous, or other), and cytoplasmic features (granular/vacuolated) . The MSRSGC has recommended 3 subcategories for SUMP: namely, cellular basaloid neoplasm, cellular oncocytic/oncocytoid neoplasm, and cellular neoplasm with clear‐cell features . In the current study, we subtyped SUMP cases based on 3 different cell types to comprise most of the diagnostic scenarios for indeterminate salivary gland FNA cases according to our own experience.…”

Section: Discussionmentioning

confidence: 99%

Subtyping salivary gland neoplasm of uncertain malignant potential based on cell type demonstrates differential risk of malignancy

Hang

Alruwaii

Zeng

et al. 2018

BACKGROUND The newly unveiled Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) has proposed salivary gland neoplasm of uncertain malignant potential (SUMP) as an indeterminate category. The category is reserved for fine‐needle aspiration (FNA) cases that are diagnostic of a salivary gland neoplasm but cannot be further designated as a specific tumor type. The objective of the current study was to evaluate the clinical utility of subtyping SUMP cases based on different cell types. METHODS A retrospective search of cytology databases at 2 institutions for salivary gland FNAs from 2006 through 2017 was conducted. The cytologic diagnosis of each case was reclassified according to the MSRSGC. Histologic follow‐up was retrieved for correlation. Cases reclassified as SUMP that had a follow‐up pathologic diagnosis were subject to cytology review and subtyping into oncocytic/squamoid, basaloid, or myoepithelial subtypes based on cytomorphology. The risk of malignancy (ROM) for each subtype was analyzed. RESULTS There were 92 SUMP cases, which comprised 5.9% of 1560 consecutive salivary gland FNAs within the 12‐year study period. Histologic follow‐up was available for 59 patients. After cytology review, there were 18 cases (30.5%) of oncocytic/squamoid subtype, 25 (42.4%) of basaloid subtype, and 16 (27.1%) of myoepithelial subtype. Pathologic correlation revealed an ROM of 61.1% (11 of 18 cases) for the oncocytic/squamoid subtype, 40.0% (10 of 25 cases) for the basaloid subtype, and 18.8% (3 of 16 cases) for the myoepithelial subtype. The differences in ROM among the 3 subtypes were statistically significant (P = .0476). CONCLUSIONS Subtyping SUMP cases into categories based on cell type demonstrated differential ROMs for better clinical stratification. Future prospective studies are mandatory to confirm this finding.

“…SUMP is defined as a neoplasm without a definitive diagnosis of a specific entity and should be used for cases in which malignancy cannot be entirely excluded. Cases in this subtype include cellular benign neoplasms, neoplasms with monomorphic lesional cells, basaloid neoplasms, oncocytic/oncocytoid neoplasms, neoplasms with clear cell features, neoplasms with atypical features, and possibly challenging low‐grade carcinoma …”

Section: Introductionmentioning

confidence: 99%

Risk of malignancy associated with cytomorphology subtypes in the salivary gland neoplasm of uncertain malignant potential (SUMP) category in the Milan System: A bi‐institutional study

Chowsilpa

Lose

et al. 2019

Self Cite

BACKGROUND: Salivary gland neoplasm of uncertain malignant potential (SUMP) is a diagnostic category in the Milan System for Reporting Salivary Gland Cytopathology. The objective of this study was to assess the risk of neoplasm (RON) and the risk of malignancy (ROM) in SUMP cases by evaluating them based on their prominent cytomorphology. METHODS:The pathology databases were searched for cases of fine-needle aspiration-diagnosed SUMP at The Johns Hopkins Hospital and Northwestern University from 2013 to 2018. Only cytopathology cases diagnosed as SUMP that had available surgical follow-up were included. RESULTS: Sixty-five patients with SUMP were identified, including 31 men and 34 women who ranged in age from 15 to 87 years (mean age, 55.2 years). Sixty-five cases had histologic follow-up, including 13 (20%) with basaloid features, 13 (20%) with oncocytic features, and 39 (60%) with unspecified features. No cases with clear cell features were found. Overall, the RON in the SUMP category was 95.4% (62 of 65 cases), and the ROM was 33.8% (22 of 65 cases). The RON in SUMPs with basaloid, oncocytic, and unspecified subtypes was 92.3%, 100%, and 94.9%, respectively, whereas the ROM was 38.5%, 7.7%, and 41%, respectively. The most common benign neoplasm was pleomorphic adenoma (23.1%), whereas mucoepidermoid carcinoma (9.2%) was the most common malignant neoplasm. CONCLUSIONS: This study shows that the ROM differs significantly based on cytomorphology subtypes, whereas the overall ROM is approximately the same as the target rate in the Milan System for Reporting Salivary Gland Cytopathology. Moreover, the RON remains high in the SUMP category among different cytomorphology subtypes.Adequate sampling, immunohistochemical staining, and familiarity with metaplastic and reactive changes may improve the diagnosis.