Masato Nakaguro1, Makoto Urano2, Ikuko Ogawa3, Hideaki Hirai4, Yoshinari Yamamoto4, Hiroshi Yamaguchi4, Maki Tanigawa4, Jun Matsubayashi4, Hiroshi Hirano5, Junji Shibahara6, Yuichiro Tada7, Toyonori Tsuzuki8, Yasuo Okada9, Yuichiro Sato10, Kenichiro Ikeda11, Aoi Sukeda4, Yumi Honda12, Yoshiki Mikami12, Toshitaka Nagao4. 1. Department of Pathology and Laboratory Medicine, Nagoya University Hospital, Nagoya, Japan. 2. Department of Diagnostic Pathology, School of Medicine, Fujita Health University, Toyoake, Japan. 3. Centre of Oral Clinical Examination, Hiroshima University Hospital, Hiroshima, Japan. 4. Department of Anatomical Pathology, Tokyo Medical University, Tokyo, Japan. 5. Department of Pathology, Tokyo Medical University Hachioji Medical Centre, Tokyo, Japan. 6. Department of Pathology, Kyorin University, Tokyo, Japan. 7. Department of Head and Neck Oncology and Surgery, International University of Health and Welfare Mita Hospital, Tokyo, Japan. 8. Department of Pathology, Aichi Medical University, Nagakute, Japan. 9. Department of Pathology, The Nippon Dental University School of Life Dentistry at Niigata, Niigata, Japan. 10. Department of Head and Neck Surgery, Niigata Cancer Centre Hospital, Niigata, Japan. 11. Head and Neck Oncology Centre, Showa University, Tokyo, Japan. 12. Department of Diagnostic Pathology, Kumamoto University Hospital, Kumamoto, Japan.
Abstract
AIMS: Minor salivary gland tumours showing a predominant papillary-cystic structure are rare, and constitute a mixture of various types of neoplasm; thus, the histopathological assessment of these tumours poses a significant diagnostic challenge. We aimed to delineate the histological characteristics of these tumours and further mutational aspects with a particular focus on sialadenoma papilliferum (SP) and intraductal papillary mucinous neoplasm (IPMN). METHODS AND RESULTS: We retrieved 28 papillary-cystic tumours of the minor salivary glands, and performed histological re-evaluation and mutation analyses of several key oncogenes. The histological classifications were as follows: SP (n = 10), SP-like intraductal papillary tumour (SP-IPT) (n = 2), IPMN (n = 9), intraductal papilloma, cystadenoma, and cystadenocarcinoma (two, three and two respectively). Whereas SP typically consisted of a combination of exophytic squamous epithelium and endophytic intraductal papillary infoldings, SP-IPT lacked the exophytic component. SP and SP-IPT frequently harboured BRAF V600E mutations (75.0%), which were identified in both squamous and ductal components. IPMN was characterised by a well-demarcated cystic lesion filled exclusively with a papillary proliferation of mucinous cells and a high rate of AKT1 E17K mutations (88.9%). Intraductal papillomas were unilocular cystic lesions with intraluminal papillary growth of bland columnar cells. In contrast, both cystadenomas and cystadenocarcinomas showed a multicystic appearance with a papillary configuration. Cystadenocarcinomas invaded the surrounding tissue and were composed of markedly atypical tumour cells. CONCLUSION: The appropriate interpretation of histological findings and specific genetic alterations (e.g. BRAF V600E and AKT1 E17K in SP and IPMN) would be useful for the correct diagnosis of minor salivary gland papillary-cystic tumours.
AIMS: Minor salivary gland tumours showing a predominant papillary-cystic structure are rare, and constitute a mixture of various types of neoplasm; thus, the histopathological assessment of these tumours poses a significant diagnostic challenge. We aimed to delineate the histological characteristics of these tumours and further mutational aspects with a particular focus on sialadenoma papilliferum (SP) and intraductal papillary mucinous neoplasm (IPMN). METHODS AND RESULTS: We retrieved 28 papillary-cystic tumours of the minor salivary glands, and performed histological re-evaluation and mutation analyses of several key oncogenes. The histological classifications were as follows: SP (n = 10), SP-like intraductal papillary tumour (SP-IPT) (n = 2), IPMN (n = 9), intraductal papilloma, cystadenoma, and cystadenocarcinoma (two, three and two respectively). Whereas SP typically consisted of a combination of exophytic squamous epithelium and endophytic intraductal papillary infoldings, SP-IPT lacked the exophytic component. SP and SP-IPT frequently harboured BRAFV600E mutations (75.0%), which were identified in both squamous and ductal components. IPMN was characterised by a well-demarcated cystic lesion filled exclusively with a papillary proliferation of mucinous cells and a high rate of AKT1E17K mutations (88.9%). Intraductal papillomas were unilocular cystic lesions with intraluminal papillary growth of bland columnar cells. In contrast, both cystadenomas and cystadenocarcinomas showed a multicystic appearance with a papillary configuration. Cystadenocarcinomas invaded the surrounding tissue and were composed of markedly atypical tumour cells. CONCLUSION: The appropriate interpretation of histological findings and specific genetic alterations (e.g. BRAFV600E and AKT1E17K in SP and IPMN) would be useful for the correct diagnosis of minor salivary gland papillary-cystic tumours.
Authors: Masato Nakaguro; Yuichiro Tada; William C Faquin; Peter M Sadow; Lori J Wirth; Toshitaka Nagao Journal: Cancer Cytopathol Date: 2020-05-18 Impact factor: 5.284
Authors: Lisa M Rooper; Lester D R Thompson; Jeffrey Gagan; Jacqueline Siok Gek Hwang; Nyall R London; Michael W Mikula; Todd M Stevens; Justin A Bishop Journal: Mod Pathol Date: 2022-03-23 Impact factor: 8.209
Authors: Sandra N Freiberger; Muriel Brada; Christine Fritz; Sylvia Höller; Alexander Vogetseder; Milo Horcic; Michel Bihl; Michal Michal; Martin Lanzer; Martin Wartenberg; Urs Borner; Peter K Bode; Martina A Broglie; Tamara Rordorf; Grégoire B Morand; Niels J Rupp Journal: Neoplasia Date: 2021-04-18 Impact factor: 5.715