Pleomorphic adenoma: the great mimicker of malignancy
Corresponding Author
Juan C Hernandez-Prera
Department of Pathology, Moffitt Cancer Center, Tampa, FL, USA
Address for correspondence: Juan C Hernandez-Prera, MD, Department of Pathology, Moffitt Cancer Center, 12902 USF Magnolia Drive, Tampa, FL 33612, USA. e-mail: [email protected]
Search for more papers by this authorAlena Skálová
Department of Pathology, Faculty of Medicine in Plzen, Charles University, Plzen, Czech Republic
Search for more papers by this authorAlessandro Franchi
Department of Translational Research and of New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
Search for more papers by this authorAlessandra Rinaldo
Department of Otolaryngology, University of Udine, Udine, Italy
Search for more papers by this authorVincent Vander Poorten
Department of Oncology, Section Head and Neck Oncology, KU Leuven, Leuven, Belgium
Otorhinolaryngology–Head and Neck Surgery, Leuven Cancer Institute, University Hospitals Leuven, Leuven, Belgium
Search for more papers by this authorPeter Zbären
Department of Otorhinolaryngology and Head and Neck Surgery, University Hospital, Bern, Switzerland
Search for more papers by this authorAlfio Ferlito
International Head and Neck Scientific Group, Padua, Italy
Search for more papers by this authorBruce M Wenig
Department of Pathology, Moffitt Cancer Center, Tampa, FL, USA
Search for more papers by this authorCorresponding Author
Juan C Hernandez-Prera
Department of Pathology, Moffitt Cancer Center, Tampa, FL, USA
Address for correspondence: Juan C Hernandez-Prera, MD, Department of Pathology, Moffitt Cancer Center, 12902 USF Magnolia Drive, Tampa, FL 33612, USA. e-mail: [email protected]
Search for more papers by this authorAlena Skálová
Department of Pathology, Faculty of Medicine in Plzen, Charles University, Plzen, Czech Republic
Search for more papers by this authorAlessandro Franchi
Department of Translational Research and of New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
Search for more papers by this authorAlessandra Rinaldo
Department of Otolaryngology, University of Udine, Udine, Italy
Search for more papers by this authorVincent Vander Poorten
Department of Oncology, Section Head and Neck Oncology, KU Leuven, Leuven, Belgium
Otorhinolaryngology–Head and Neck Surgery, Leuven Cancer Institute, University Hospitals Leuven, Leuven, Belgium
Search for more papers by this authorPeter Zbären
Department of Otorhinolaryngology and Head and Neck Surgery, University Hospital, Bern, Switzerland
Search for more papers by this authorAlfio Ferlito
International Head and Neck Scientific Group, Padua, Italy
Search for more papers by this authorBruce M Wenig
Department of Pathology, Moffitt Cancer Center, Tampa, FL, USA
Search for more papers by this authorAbstract
Pleomorphic adenoma (PA) is the most common salivary gland neoplasm, and its diagnosis is straightforward in the majority of cases. However, not infrequently, PA shows unusual and uncommon histological features that can be confused with those of malignancy. The difficulties in diagnosing PA arise from its ability to mimic invasion, show atypical or metaplastic cytomorphology, and show morphological features that overlap with those of established salivary gland carcinomas. In addition, recognising early malignant transformation to carcinoma ex-pleomorphic adenoma continues to be a frequent challenge. This review describes the diagnostic pitfalls of PA, and offers a systematic approach to avoid them by combining classic histopathology with novel immunohistochemical and molecular tests.
Graphical Abstract
Not infrequently pathologists encounter cases in which the diagnosis of pleomorphic adenoma may prove difficult. In such cases, the diagnostic dilemma can be solved by asking three practical questions. However, due to the morphological diversity of pleomorphic adenoma there are pitfalls that make it difficult to give clear answers to these questions.
Conflict of interest
The authors do not report any conflicts of interest.
Open Research
Data Availability Statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.
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