Salivary gland pathologies: evolution in classification and association with unique genetic alterations

Abstract

Purpose The correct classification of salivary gland pathologies is crucial for choosing a treatment method and determining the prognosis. Better outcomes are now achievable thanks to the introduction of new therapy approaches, such as targeted therapies for malignant salivary gland tumors. To apply these in clinical routine, a clear classification of the lesions is required. Methods The following review examines all changes from the first World Health Organization (WHO) Classification of salivary gland pathologies from 1972 to fifth edition from 2022. Possible developments in the diagnosis and classification of salivary gland pathology are also presented. Results The current WHO classification is the fifth edition. With the development of new diagnostic methods, based on genetic alterations, it provides insight into the molecular basis of lesions. This has resulted in the evolution of classification, introduction of new entities and reclassification of existing ones. Conclusions Genetic alterations will become increasingly more significant in the identification of salivary gland pathologies in the future. These alterations will be helpful as prognostic and predictive biomarkers, and may also serve as targets for anti-cancer therapies.

Salivary gland-type cancers: cross-organ demographics of a rare cancer

“…Fourthly, pathological diagnosis was given by several different pathologists without obtaining consensus. In addition, although the WHO histological classification was revised at 2017 [ 18 ] during the present study period, pathological reevaluation was not performed for patients diagnosed before the revision. Fifthly, a definitive comparison of the survival times was difficult because of the different stage distribution and different definitions of disease stages according to the primary site.…”

Beyond Ultrasound: Multimodal Cross-Sectional Imaging for Preoperative Imaging of Parotid Gland Tumors: A Primer for Radiology Trainees

“…Typical necrotic areas in solid tumors have been described and are best recognized with post-contrast CT imaging and fat-suppressed contrast-enhanced T1 MR images (Figure 7) [78]. [73]. PACs do not frequently develop de novo or from a pre-existing PA within the major salivary glands [72].…”

“…Polymorphous adenocarcinomas (PACs) most commonly occur in the oral cavity and oropharyngeal minor salivary glands [72]. They were previously known as polymorphous low-grade adenocarcinomas prior to the new WHO classification of salivary gland tumors [73]. PACs do not frequently develop de novo or from a pre-existing PA within the major salivary glands [72].…”

Current Developments in Diagnosis of Salivary Gland Tumors: From Structure to Artificial Intelligence

“…Tumors previously known as sebaceous and non-sebaceous lymphadenomas are now classified only as LAs. LAs are the biphasic benign tumors with lymphoid stroma and epithelial components represented Changes in classification of salivary glands lesions [19] BSGET SGM Other The evolution of these classifications and the introduction of new terms are important aspects for a better understanding of salivary gland lesion diagnosis. Now the benign salivary tumors have lymphadenomas (LA) and DP categories.…”

“…Figure1. Salivary gland entities reported in WHO from 1972 to 2022[19]. BSGE = salivary gland benign epithelial tumors; SGM = salivary gland malignancies; Other = non-epithelial, soft tissue, lymphoid, secondary or unclassified salivary gland entities.…”