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Head and Neck Pathology Mar 2022The 5 edition of the World Health Organization (WHO) Classification of Head and Neck Tumours (2022) comes out only five years after the previous edition, however it...
The 5 edition of the World Health Organization (WHO) Classification of Head and Neck Tumours (2022) comes out only five years after the previous edition, however it presents important updates that run in parallel with the rapid progression involving the increasingly sophisticated molecular investigation and its interpretation, some of which already have therapy-related impact. This manuscript provides an overview of the leading changes introduced in the classification of Odontogenic and Maxillofacial Bone Tumours that encompasses cysts of the jaws, odontogenic tumours, giant cell lesions and bone cysts, and bone and cartilage tumours. This is the first edition that Essential and Desirable Diagnostic Features were added for each entity, so that the most important clinical, microscopic and/or radiologic features were encapsulated and briefly highlighted. Surgical ciliated cyst was added to the group of odontogenic cysts, adenoid ameloblastoma was a newly recognized benign epithelial odontogenic tumour, and segmental odontomaxillary dysplasia was introduced in the group of fibro-osseous tumours and dysplasia. In addition, rhabdomyosarcoma with TFCP2 rearrangement, was introduced into the group of malignant jawbone tumours. The unique genetic aberrations distinguish it from other types of rhabdomyosarcomas. On the other hand, melanotic neuroectodermal tumour of infancy and osteoid osteoma were deleted from the benign bone and cartilageneous tumours, as was the hematolymphoid tumour of solitary plasmacytoma of bone. We systematically reviewed each entity in this chapter and provided important updated findings for selected topics that can further aid in the diagnostic process for challenging cases, broaden insights on the logic of the present classification, and finally, emphasize the potential that some of the molecular results may have in the near future to set new treatment approaches.
Topics: Bone Neoplasms; DNA-Binding Proteins; Head and Neck Neoplasms; Humans; Odontogenic Cysts; Odontogenic Tumors; Transcription Factors; World Health Organization
PubMed: 35312978
DOI: 10.1007/s12105-021-01404-7 -
Turk Patoloji Dergisi 2022The 5th edition of the World Health Organization (WHO) Classification of Head and Neck Tumors opened to online access in March 2022. This edition is conceptually similar... (Review)
Review
The 5th edition of the World Health Organization (WHO) Classification of Head and Neck Tumors opened to online access in March 2022. This edition is conceptually similar to the previous classification of odontogenic lesions. The only newly defined entity in odontogenic lesions is adenoid ameloblastoma, which is classified under benign epithelial odontogenic tumors. While not odontogenic, the surgical ciliated cyst is a new entry to the cyst classification of the jaws. In other respects, a very important change was made in the new blue books that added 'essential and desirable diagnostic criteria' for each entity to highlight the features considered indispensable for diagnosis. In this article, we review the odontogenic tumors and cysts of the jaw sections of the Odontogenic and Maxillofacial Bone Tumors Chapter, outlining changes from the 2017 WHO classification and summarizing the essential diagnostic criteria and new developments.
Topics: Ameloblastoma; Head and Neck Neoplasms; Humans; Odontogenic Cysts; Odontogenic Tumors; World Health Organization
PubMed: 35578902
DOI: 10.5146/tjpath.2022.01573 -
International Journal of Molecular... Feb 2021The macroscopic and microscopic anatomy of the oral cavity is complex and unique in the human body. Soft-tissue structures are in close interaction with mineralized... (Review)
Review
The macroscopic and microscopic anatomy of the oral cavity is complex and unique in the human body. Soft-tissue structures are in close interaction with mineralized bone, but also dentine, cementum and enamel of our teeth. These are exposed to intense mechanical and chemical stress as well as to dense microbiologic colonization. Teeth are susceptible to damage, most commonly to caries, where microorganisms from the oral cavity degrade the mineralized tissues of enamel and dentine and invade the soft connective tissue at the core, the dental pulp. However, the pulp is well-equipped to sense and fend off bacteria and their products and mounts various and intricate defense mechanisms. The front rank is formed by a layer of odontoblasts, which line the pulp chamber towards the dentine. These highly specialized cells not only form mineralized tissue but exert important functions as barrier cells. They recognize pathogens early in the process, secrete antibacterial compounds and neutralize bacterial toxins, initiate the immune response and alert other key players of the host defense. As bacteria get closer to the pulp, additional cell types of the pulp, including fibroblasts, stem and immune cells, but also vascular and neuronal networks, contribute with a variety of distinct defense mechanisms, and inflammatory response mechanisms are critical for tissue homeostasis. Still, without therapeutic intervention, a deep carious lesion may lead to tissue necrosis, which allows bacteria to populate the root canal system and invade the periradicular bone via the apical foramen at the root tip. The periodontal tissues and alveolar bone react to the insult with an inflammatory response, most commonly by the formation of an apical granuloma. Healing can occur after pathogen removal, which is achieved by disinfection and obturation of the pulp space by root canal treatment. This review highlights the various mechanisms of pathogen recognition and defense of dental pulp cells and periradicular tissues, explains the different cell types involved in the immune response and discusses the mechanisms of healing and repair, pointing out the close links between inflammation and regeneration as well as between inflammation and potential malignant transformation.
Topics: Animals; Antigens, Neoplasm; Carcinogenesis; Carcinoma, Squamous Cell; Chemokines; Complement System Proteins; Dental Caries; Dental Pulp; Dentin; Fibroblasts; Humans; Intracellular Signaling Peptides and Proteins; Mesenchymal Stem Cells; Mouth Neoplasms; Nerve Net; Neuropeptides; Nitric Oxide; Odontoblasts; Periapical Granuloma; Periapical Periodontitis; Periapical Tissue; Pulpitis; Radicular Cyst
PubMed: 33540711
DOI: 10.3390/ijms22031480 -
Pediatric Radiology Aug 2022Aneurysmal bone cyst (ABC) is a benign but locally aggressive lesion that predominantly affects children and young adults. ABC, which accounts for approximately 70% of... (Review)
Review
Aneurysmal bone cyst (ABC) is a benign but locally aggressive lesion that predominantly affects children and young adults. ABC, which accounts for approximately 70% of the cases, is now recognized to be a true neoplasm, whereas ABC-like changes associated to other bone neoplasms (also referred in the literature as secondary ABC) accounts for the remaining 30%. The solid variant of ABC is also considered a true neoplasm but is rare. ABC can involve any bone in the body, and although it has a metaphyseal preference, it can involve any part of a bone and soft tissues. As with any bone tumor, the initial evaluation of ABCs should be done with radiographs followed by magnetic resonance imaging or less frequently computed tomography for further characterization. The imaging appearance of ABC is variable; however, a lytic and expansile lesion with fluid-fluid levels is the most common presentation. The main differential diagnosis of an ABC in the pediatric population is unicameral bone cyst (UBC) and telangiectatic osteosarcoma, therefore a biopsy is recommended before treatment. The therapeutic options of ABC range from curettage with or without adjuncts such as phenol, liquid nitrogen, argon laser and bone grafting or bone substitutes to more recently employed alternatives such as image-guided sclerotherapy with various sclerosing agents and monoclonal antibodies (e.g., Denosumab).
Topics: Bone Cysts; Bone Cysts, Aneurysmal; Bone Neoplasms; Child; Humans; Osteosarcoma; Tomography, X-Ray Computed; Young Adult
PubMed: 35941207
DOI: 10.1007/s00247-022-05396-6 -
International Journal of Oral and... Nov 2022The treatment of odontogenic keratocysts is reviewed in light of the aetiology and pathogenesis of these lesions. The role of the dental lamina and submucosal hamartias,... (Review)
Review
The treatment of odontogenic keratocysts is reviewed in light of the aetiology and pathogenesis of these lesions. The role of the dental lamina and submucosal hamartias, as frequently seen in nevoid basal cell carcinoma syndrome, is discussed, and the implications for treatment are emphasized.
Topics: Humans; Neoplasm Recurrence, Local; Odontogenic Cysts; Odontogenic Tumors; Basal Cell Nevus Syndrome
PubMed: 35277291
DOI: 10.1016/j.ijom.2022.02.005 -
The Pan African Medical Journal 2021Dentigerous cysts, also called follicular cysts, are slow-growing benign odontogenic cysts that are thought to be developmental in origin. On imaging, they usually... (Review)
Review
Dentigerous cysts, also called follicular cysts, are slow-growing benign odontogenic cysts that are thought to be developmental in origin. On imaging, they usually present as a well-defined and unilocular radiolucency surrounding the crown of an unerupted or impacted tooth. This article presents a case of unilateral mandibular dentigerous cysts associated with unerupted mandibular canine in a healthy patient treated by enucleation, along with a review of the literature and an examination of the treatment modality. The aim of this paper is to highlight how to choose the adequate treatment for dentigerous cyst cases.
Topics: Dentigerous Cyst; Humans
PubMed: 34925684
DOI: 10.11604/pamj.2021.40.149.28645 -
Head and Neck Pathology Mar 2022The initiative of the 5th edition of the WHO classification of the Head and Neck Tumours establishing a new section dedicated to familial/heritable tumor syndromes with... (Review)
Review
The initiative of the 5th edition of the WHO classification of the Head and Neck Tumours establishing a new section dedicated to familial/heritable tumor syndromes with tumors and lesions in the head and neck region was much needed to better understand the tumours, diseases, and associated syndromes, as well as establish recommendations for monitoring and treating these patients. (WHO Classification of Tumours Editorial Board. Head and Neck tumours. Lyon (France): International Agency for Research on Cancer; 2022. https://publications.iarc.fr/ ). Within the newly established chapter on genetic tumor syndromes, we have described the main manifestations on the head and neck region in 15 syndromes. This review highlights the important findings within these syndromes, especially on the update on syndromes with tumors involving the head and neck region, as Gorlin syndrome/nevoid basal cell carcinoma syndrome associated with odontogenic keratocysts; Brooke-Spiegler syndrome/familial cylindromatosis and the associated membranous-type salivary gland basal cell adenoma, PTEN hamartoma tumor syndrome/Cowden syndrome with associated facial skin and mucosal lesions and characteristic multinodular thyroid lesions, Von Hippel Lindau syndrome and the associated middle ear endolymphatic sac tumor, as well as the fascinating genetic aspects of the diverse Head and Neck Paragangliomas. We will also discuss hyperparathyroidism-jaw tumor syndrome is characterized by parathyroid tumors in association with fibro-osseous jaw tumors, as well as head and neck desmoid tumors associated with familial adenomatous polyposis with Gardner syndrome variant familial, multicentric head and neck squamous cell carcinoma, tuberous sclerosis and neurofibromatosis type 1-associated head and neck lesions.
Topics: Basal Cell Nevus Syndrome; Hamartoma Syndrome, Multiple; Head and Neck Neoplasms; Humans; Neoplastic Syndromes, Hereditary; Skin Neoplasms; World Health Organization
PubMed: 35312981
DOI: 10.1007/s12105-022-01414-z -
Canadian Journal of Dental Hygiene :... Oct 2021Dentigerous cysts are one of the most common developmental types of odontogenic cysts occurring in the oral cavity and often manifest as incidental findings on dental... (Review)
Review
Dentigerous cysts are one of the most common developmental types of odontogenic cysts occurring in the oral cavity and often manifest as incidental findings on dental radiographs and/or as asymptomatic swellings. These cysts develop from remnants of reduced enamel epithelium around the crown of an unerupted or impacted tooth, attached at the level of the cementoenamel junction. Most are considered developmental. However, in young clients they may be inflammatory in origin, the result of caries in the primary dentition. This short communication highlights a case of an asymptomatic dentigerous cyst identified in a 4-year-old child and subsequent enucleation under general anesthesia. A thorough clinical and radiographic assessment of the oral cavity in pediatric clients merits a review of dentigerous cysts by the dental hygienist.
Topics: Child; Child, Preschool; Dental Caries; Dentigerous Cyst; Humans; Odontogenic Cysts; Tooth, Deciduous; Tooth, Impacted
PubMed: 34925518
DOI: No ID Found -
European Endodontic Journal Jan 2023Inflammatory radicular cysts (IRCs) are chronic lesions that follow the development of periapical granulomas (PGs). IRCs result from multiple inflammatory reactions led... (Review)
Review
Inflammatory radicular cysts (IRCs) are chronic lesions that follow the development of periapical granulomas (PGs). IRCs result from multiple inflammatory reactions led initially by several pro-inflammatory interleukins and growth factors that provoke the proliferation of epithelial cells derived from epithelial cell rests of Malassez present in the granulomatous tissue, followed by cyst formation and growth processes. Multiple theories have been proposed to help explain the molecular process involved in the development of the IRC from a PG. However, although multiple studies have demonstrated the presence of epithelial cells in most PGs, it is still not fully understood why not all PGs turn into IRCs, even though both are stages of the same inflammatory phenomenon and receive the same antigenic stimulus. Histopathological examination is currently the diagnostic gold standard for differentiating IRCs from PGs. Although multiple studies have evaluated the accuracy of non-invasive or minimally invasive methods in assessing the histopathological nature of the AP before the intervention, these studies' results are still controversial. This narrative review addresses the biological insights into the complex molecular mechanisms of IRC formation and its histopathological features. In addition, the relevant inflammatory molecular mediators for IRC development and the accuracy of non-invasive or minimally invasive diagnostic approaches are summarised. (EEJ-2022-03-041).
Topics: Humans; Radicular Cyst; Epithelial Cells; Inflammation; Periapical Granuloma; Intercellular Signaling Peptides and Proteins
PubMed: 36748442
DOI: 10.14744/eej.2022.26918