How important are the cytomorphologic subtypes of the salivary gland neoplasm of uncertain malignant potential (SUMP) category in the Milan system for reporting salivary gland cytology? An institutional experience 2018-2024.

INTRODUCTION: Salivary gland neoplasm of uncertain malignant potential (SUMP) is an important diagnostic category of the Milan System for reporting salivary gland cytology (MSRSGC). Further subcategorization by cytomorphologic subtypes has been recommended to risk-stratify cases. In this study, our institutional experience with the risk of neoplasm (RON) and risk of malignancy (ROM) based on cytomorphologic subcategorization of SUMP is reported. We also report the prevalence of malignancy (POM) at our institution. METHODS: The pathology database was queried for cases of fine-needle aspiration (FNA) diagnosed as SUMP along with follow-up at our institution from 2018-February 2024. This study was approved by an institutional review board. RESULTS: Of 1159 cases of salivary gland FNA specimens reported as per MSRSGC at our institution, 14.8% (171/1159 cases) were diagnosed as SUMP, with these reports verified by at least 16 cytopathologists. Surgical follow-up was available for 139/171 (81.3%) of these cases, for which the original cytomorphologic subgroups were as follows: 65 (46.8%) basaloid, 48 (34.5%) oncocytic/oncocytoid, 14 (10.1%) myoepithelial, 9 (6.5%) other, 2 (1.4%) clear cell, and 1 (0.7%) mucinous. The POM within SUMP at our institution is within a range of 29.8%-36.7%. When considering all cases, our institutional RON for SUMP was 97.8% (136/139), and the ROM was 36.7% (51/139). Notably, a significant portion of cases (36%, 50/139) underwent review at a daily intradepartmental consensus conference. Analysis revealed that SUMP cases that underwent consensus review had a ROM of 46% (23/50), versus 31.5% (28/89) in independently verified cases (p = .13). Of the cytomorphologic subgroups, basaloid SUMP in particular was more likely to be benign on resection when the case had been independently verified than after consensus review (p = .0082). When considering only the independently verified cases, the ROM for each subgroup was as follows: 38.7% (12/31) in oncocytic/oncocytoid, 20% (9/45) in basaloid, 33.3% (2/6) in myoepithelial, 60% (3/5) in "other", and 100% (1/1) in both mucinous and clear cell (p = .0407). CONCLUSION: While the RON is high across all cytomorphologic subgroups of SUMP, the ROM does vary across the groups, with basaloid cytomorphology having the lowest ROM. This effect is seen in independently verified cases but not in cases having undergone consensus review.

Rapid on-site evaluation in percutaneous core needle biopsies of renal masses: Cytologic-histologic concordance and diagnostic challenges.

BACKGROUND: Image-guided fine needle aspirations (FNAs) and core needle biopsies (CNBs) play the critical role in diagnosis of renal lesions. Rapid on-site evaluation (ROSE) can potentially increase the adequacy rate and improve diagnostic yield, while providing additional information for rapid clinical decisions. The aim of this study is to evaluate the diagnostic utility of ROSE in obtaining adequate tissue for diagnosis of renal lesions in our institution. METHODS: We retrospectively reviewed all percutaneous renal CNB cases with available ROSE interpretations for a 11-year period. The ROSE interpretations and CNB diagnoses was compared and the concordance rate was calculated accordingly. The discrepant cases were re-reviewed and the possible causes for discrepancy were analyzed. RESULTS: A total of 189 cases were identified. Definitive diagnoses were rendered in 164 (87%) cases on the final CNBs, including primary renal lesions in 151 cases and metastatic malignancies in 13 cases. At the time of ROSE, samples were deemed to be adequate in the majority of cases (83%). The calculated concordance rate between ROSE interpretations and CNB final diagnoses was 84.6%. Sampling issue and scant tumor cells were the main causes for the discordance between ROSE interpretations and CNB diagnoses. CONCLUSION: Our study showed a relatively high-concordance rate of 84.6% between ROSE interpretations and CNB final diagnoses, suggesting that ROSE is a valuable tool for procurement of adequate renal CNB samples for diagnosis.

Utility of rapid on-site evaluation in procurement of adrenal gland tissue biopsies.

BACKGROUND: While the number of adrenal biopsies has increased due to more "incidentalomas" were detected by widespread use of imaging studies, there have been very limited studies to evaluate the utility of rapid on-site evaluation (ROSE) in obtaining adequate core needle biopsy (CNB) tissue for diagnosis of adrenal lesions. METHODS: We retrospectively reviewed all percutaneous adrenal CNB cases with available ROSE for a 12-year period in our institute in order to assess the usefulness of ROSE in adrenal CNB sampling. RESULTS: A total of 83 cases were identified in our database. The majority of cases (52/83, 63%) were diagnosed as metastatic malignancies with the lung being the most common primary site. Adrenal hyperplasia/adenoma was the most common primary adrenal lesion. The concordance between the ROSE interpretations and CNB final diagnoses is 80%. The interpretation errors accounted for majority (11/17, 65%) of the discordant cases. CONCLUSION: ROSE assessment during adrenal CNB procedures is a helpful tool for obtaining adequate diagnostic tissue. Pathologists should be familiar with adrenal cytology in order to reduce interpretation errors at ROSE.