The effectiveness of the Milan system for risk stratification of salivary gland lesions: The 10‐year cytohistopathological correlation results of salivary gland <scp>FNA</scp> cytology at a tertiary center

BACKGROUND:The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) reports a 25% rate of malignancy (ROM) for the Milan I: Nondiagnostic (ND) category. We clarify the ROM of ND salivary gland fine-needle aspirations (SGFNAs) based on our institutional experience and review of the literature. METHODS: Overall risk of malignancy (OROM) and that for those with surgical/flow cytometric follow-up (FROM) for each category and "all-comers" were calculated for Emory SGFNAs from January 2010 through March 2021. From a literature review of 50 articles using MSRSGC, distribution of diagnoses, rates of follow-up, FROM, and OROM by category were calculated. FROMs and OROMs between ND FNAs and all-comers were compared. Milan I rate was compared with the ratio of Milan I OROM to all-comer OROM. RESULTS:Of 819 SGFNAs at Emory, 12.8% (n = 105/819) were ND. Thirty-two had known follow-up, with 12 (37.5%) being malignant.Nonmucinous cyst contents accounted for 26.7% of ND SGFNAs (n = 28/105); all 7 with surgical follow-up were benign. Of 50 MSRSGC studies, 18.2% (n = 2384/13,129) of SGFNAs were classified as ND, 26.6% (n = 635/2384) with known follow-up.Total FROM and OROM for ND FNAs (15.7% and 4.1%, respectively) were significantly lower than those for all-comers (24.9% and 11.4%, respectively) (p < .001). There was no relationship between rate of ND SGFNA and ND ROM. CONCLUSIONS: The ND category is associated with a lower ROM than that of all-comer SGFNA patients. The "true" ROM for ND SGFNAs is likely best estimated by the 4.1% OROM. SGFNAs showing nonmucinous cyst contents have a particularly low ROM. Rate of ND SGFNAs does not influence ND ROM. Cancer Cytopathol 2022; 0:-.

Section: Resultsmentioning

confidence: 82%

Nondiagnostic salivary gland FNAs are associated with decreased risk of malignancy compared with “all‐comer” patients: Analysis of the Milan System for Reporting Salivary Gland Cytopathology with a focus on Milan I: Nondiagnostic

Lui

Tenney

Mullane

et al. 2022

“…After reviewing the titles and abstracts, 54 articles were excluded. The full texts of the remaining 80 articles were reviewed, and 35 articles 5–39 were finally included in the systematic review and meta‐analysis.…”

Section: Resultsmentioning

confidence: 99%

Application of the Milan System for Reporting Salivary Gland Cytopathology: A systematic review and meta‐analysis

Wang

Zhao

et al. 2022

BACKGROUND:The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) is a standard, evidence-based classification system for salivary gland fine-needle aspiration (SG-FNA). Since it was published in 2018, many researchers across the world have applied this uniform reporting system to their cohorts. METHODS: The authors comprehensively reviewed cohort studies conducted since publication of the MSRSGC and performed a meta-analysis. The risk of neoplasm and the risk of malignancy (ROM) were calculated for each diagnostic category, and their diagnostic efficacy was evaluated. RESULTS:Thirty-five studies were included in the meta-analysis. The total number of SG-FNAs was 10,706, and 7168 of those had histopathologic follow-up. The ROM for each category was: nondiagnostic, 11.4%; nonneoplastic, 10.9%; atypia of undetermined significance, 30.5%; neoplasm-benign, 2.8%; neoplasm-salivary gland neoplasm of uncertain malignant potential, 37.7%; suspicious for malignancy, 83.8%; and malignant, 97.7%. Low-level heterogeneity was observed in ROM estimation. The sensitivity, specificity, and diagnostic odds ratio for differentiating malignant and benign lesions were 88.0%, 98.5% and 520.3, respectively. CONCLUSIONS: The reporting of SG-FNA using the MSRSGC demonstrated high diagnostic accuracy. The ROM for each category was generally concordant with the recommendations, except for the suspicious for malignancy category, which was significantly higher than the reference value. The tiered, standardized classification system would benefit the clinical management of salivary gland lesions. Cancer Cytopathol 2022;

“…In contrast to this low malignancy risk, MSRSGC estimates the general ROM in nondiagnostic aspirates to be approximately 25% and recommends repeat FNA, imaging studies such as contrast‐enhanced CT/MRI, alternative biopsy approaches, or surgery 18 . Recent studies with large number of cases reporting on the application of MSRSGC have shown variable ROMs for the nondiagnostic category, ranging from 0% to 20% 17,19,21‐27 . These case series, together with 2 minimally overlapping meta‐analyses, 17,21 are summarized in Table 6.…”

Section: Discussionmentioning

confidence: 99%

“…18 Recent studies with large number of cases reporting on the application of MSRSGC have shown variable ROMs for the nondiagnostic category, ranging from 0% to 20%. 17,19,[21][22][23][24][25][26][27] These case series, together with 2 minimally overlapping meta-analyses, 17,21 are summarized in Table 6. Only studies that incorporated at least 300 total FNAs with at least 100 histologic follow-up were included in this summary.…”

Section: Cancer Cytopathology August 2022mentioning

confidence: 99%

Nondiagnostic category of Milan System for Reporting Pediatric Salivary Gland Cytopathology: outcomes and root cause analysis

Wang

Liang

Belcher

et al. 2022

BACKGROUND: Fine-needle aspiration (FNA) results classified as the nondiagnostic category of the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) may be infrequently encountered in children. Clinical management may be challenging due to lack of data regarding outcomes and underlying causes. METHODS: We retrospectively analyzed 106 consecutive pediatric salivary gland FNAs (2000-2020; 45% performed under image guidance). The outcomes of patients with nondiagnostic results were analyzed. Clinical parameters, FNA procedural parameters, and histopathologic parameters were compared between diagnostic and nondiagnostic cases. A root cause analysis was performed using the fishbone diagram and the 5 Whys method. RESULTS: A total of 103 initial FNAs were identified. The nondiagnostic rates for initial and repeat biopsy were 16% (16/103) and 67% (2/3), respectively. Initial nondiagnostic FNAs were most frequently managed by clinical/radiologic follow-up only (56%, 9/16), followed by direct surgery (19%, 3/16) and repeat FNA (19%, 3/16).By histologic and clinical/radiologic follow-up, the risk of malignancy for nondiagnostic cases was zero. Palpation guidance (P < .05), inadequate sampling determined by rapid on-site evaluation (P < .01), and lesions with cystic, vascular, or diffuse nature (P < .05) were significantly associated with nondiagnostic results. By root cause analysis, proceduralist sampling error and lack of ultrasound guidance were the most common primary and secondary causes, respectively. CONCLUSIONS: Pediatric salivary gland lesions of the nondiagnostic MSRSGC category have minimal risk of malignancy and may be successfully managed by clinical/radiologic follow-up. The root causes for nondiagnostic results were often multifactorial and primarily related to proceduralist sampling, characteristics of the lesions, and lack of ultrasound guidance. Cancer Cytopathol