Histopathology. 2021 May 27. doi: 10.1111/his.14421. Online ahead of print.
ABSTRACT
AIMS: There is widespread perception in clinic and pathology, that the histomorphological assessment of minor salivary gland tumours (MinSG) is more difficult and hampared by more misdiagnoses than that of major salivary glands. This is based on a vague, subjective clinical impression, while scientific proof of the difference and of potentional reasons that would explain this are lacking.
METHODS AND RESULTS: We identified fourteen putative clinical, pathological, and combined clinico-pathological reasons, which altogether could explain the phenomenon of perceived greater diagnostic difficulty of tumours of MinSG. We performed a comprehensive literature search and a statistical comparison of data from a large personal consultation series (biased for difficult cases) with cumulative data from straightforward, unselected (non-consultation) series from the literature. By that comparison we could prove with statistical significance a comprehensive series of reasons, as well as of consequences of greater diagnostic difficulty in MinSG.
CONCLUSIONS: Within the 14 criteria a high frequency of initial incisional biopsies and of low-grade category in malignant tumours emerged as the two most important reasons for enhanced diagnostic difficulty. Very rare entities, unusual locations, shortcomings in clinico-pathological communication, as well as pecularities of the special anatomic location of the hard palate, such as tumour necrosis, mucosal ulceration, pseudoinvasion, and the peculiar phenomenon of “tumoural-mucosal fusion”, contribute to further diagnostic difficulties. The awareness of these shortcomings and pitfalls enables a series of recommendations for clinic and pathology, which might help aid assessment and reduce the rate of misdiagnosis in tumours of MinSG.
PMID:34042205 | DOI:10.1111/his.14421
