TY - JOUR
T1 - A multi-institutional study of salivary gland cytopathology
T2 - Application of the Milan System for Reporting Salivary Gland Cytopathology in Japan
AU - Higuchi, Kayoko
AU - Urano, Makoto
AU - Akiba, Jun
AU - Nogami, Miwako
AU - Hirata, Yukiya
AU - Zukeran, Yoko
AU - Moriyoshi, Koki
AU - Tada, Yuichiro
AU - Fukushima, Mana
AU - Obayashi, Mariko
AU - Sakamoto, Shinnichi
AU - Kuraoka, Kazuya
AU - Kira, Kana
AU - Kawahara, Akihiko
AU - Kato, Taku
AU - Tanigawa, Maki
AU - Nakaguro, Masato
AU - Yamamoto, Hidetaka
AU - Nagao, Toshitaka
N1 - Funding Information:
This study was supported by the research fund of the Japanese Society of Clinical Cytology.
Funding Information:
This study was supported by the research fund of the Japanese Society of Clinical Cytology. Salivary gland fine-needle aspiration cytology (FNAC) is a useful tool for preoperatively diagnosing salivary gland lesions. It can be used to differentiate neoplastic salivary gland lesions from non-neoplastic lesions and benign tumors from highly malignant tumors.1-3 However, because of the inherent complexity of interpreting salivary gland FNAC findings and the lack of a uniform reporting format, salivary gland FNAC performance varies among institutions.4 The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) was introduced in 2018 and is an evidence-based classification scheme for addressing these issues with salivary gland cytology.5-7 It provides the risk of malignancy (ROM) for 7 diagnostic categories, along with recommendations for clinical management. The 7 diagnostic categories are nondiagnostic (ND), non-neoplastic (NN), atypia of undetermined significance (AUS), neoplasm-benign (NB), salivary gland neoplasm of uncertain malignant potential (SUMP), suspicious for malignancy (SFM), and malignant (M).5-7 Use of the MSRSGC is currently spreading throughout the world, and many studies about its application in Asian countries, including Japan, have been published.8-11 Salivary gland tumors are as uncommon in Japan, where they represent 6.1% of head and neck cancers and 0.2% of all malignancies, as they are in other countries; eg, they account for 6% of head and neck cancers and 0.3% of all malignancies in the United States.12,13 Consequently, no large-scale studies of salivary gland FNAC have been conducted in Japan. The study reported herein was 1 of the largest studies of the MSRSGC in the world7-11,14-19 and the first multi-institutional study of the application of the MSRSGC in Japan. With the support of the Japanese Society of Clinical Cytology, we demonstrated the usefulness of the MSRSGC in the diagnosis of salivary gland lesions and for the quality control of salivary gland cytology results.
Publisher Copyright:
© 2021 The Authors. Cancer Cytopathology published by Wiley Periodicals LLC on behalf of American Cancer Society
PY - 2022/1
Y1 - 2022/1
N2 - Background: The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) is a risk-stratification reporting system that was introduced in 2018. The objective of this multi-institutional study was to evaluate the utility of the MSRSGC in Japan. Methods: In total, 1608 fine-needle aspiration samples with matching histologic diagnoses were retrieved from 12 large institutions in Japan. The diagnostic categories of the MSRSGC were assigned prospectively or retrospectively, and the results were compared with the histologic diagnoses. Results: The cases were classified as follows: nondiagnostic, 18.1%; non-neoplastic, 4.1%; atypia of undetermined significance, 11.5%; neoplasm-benign, 43.7%; salivary gland neoplasm of uncertain malignant potential, 9.6%; suspicious for malignancy, 3.6%; and malignant, 9.4%. The risk of neoplasm and the risk of malignancy in each MSRSGC category were as follows: nondiagnostic, 72.9% and 13.4%, respectively; non-neoplastic, 15.2% and 9.1%, respectively; atypia of undetermined significance, 77.9% and 24.9%, respectively; neoplasm-benign, 99% and 1.8%, respectively; salivary gland neoplasm of uncertain malignant potential, 94.8% and 37%, respectively; suspicious for malignancy, 100% and 89.7%, respectively; and malignant, 100% and 99.3%, respectively. The accuracy of the MSRSGC for diagnosing neoplasms was 97.8%, and its accuracy for diagnosing malignancy was 97.3%. Institutions that used Romanowsky-stained preparations had lower nondiagnostic rates and lower risks of neoplasm and malignancy in the non-neoplastic category. Conclusions: The MSRSGC is useful for risk stratification and quality control. Widespread use of the MSRSGC would improve the accuracy of salivary gland cytology and lead to better patient care in Japan.
AB - Background: The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) is a risk-stratification reporting system that was introduced in 2018. The objective of this multi-institutional study was to evaluate the utility of the MSRSGC in Japan. Methods: In total, 1608 fine-needle aspiration samples with matching histologic diagnoses were retrieved from 12 large institutions in Japan. The diagnostic categories of the MSRSGC were assigned prospectively or retrospectively, and the results were compared with the histologic diagnoses. Results: The cases were classified as follows: nondiagnostic, 18.1%; non-neoplastic, 4.1%; atypia of undetermined significance, 11.5%; neoplasm-benign, 43.7%; salivary gland neoplasm of uncertain malignant potential, 9.6%; suspicious for malignancy, 3.6%; and malignant, 9.4%. The risk of neoplasm and the risk of malignancy in each MSRSGC category were as follows: nondiagnostic, 72.9% and 13.4%, respectively; non-neoplastic, 15.2% and 9.1%, respectively; atypia of undetermined significance, 77.9% and 24.9%, respectively; neoplasm-benign, 99% and 1.8%, respectively; salivary gland neoplasm of uncertain malignant potential, 94.8% and 37%, respectively; suspicious for malignancy, 100% and 89.7%, respectively; and malignant, 100% and 99.3%, respectively. The accuracy of the MSRSGC for diagnosing neoplasms was 97.8%, and its accuracy for diagnosing malignancy was 97.3%. Institutions that used Romanowsky-stained preparations had lower nondiagnostic rates and lower risks of neoplasm and malignancy in the non-neoplastic category. Conclusions: The MSRSGC is useful for risk stratification and quality control. Widespread use of the MSRSGC would improve the accuracy of salivary gland cytology and lead to better patient care in Japan.
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U2 - 10.1002/cncy.22505
DO - 10.1002/cncy.22505
M3 - Article
C2 - 34478237
AN - SCOPUS:85114136514
SN - 1934-662X
VL - 130
SP - 30
EP - 40
JO - Cancer cytopathology
JF - Cancer cytopathology
IS - 1
ER -