Seminars in Diagnostic Pathology最新文献

Ameloblastoma is a benign odontogenic epithelial tumor characterized by its aggressive behavior and a high likelihood of local recurrence if not fully excised. Ameloblastomas are a common type of slow-growing, true jaw tumor which may present as solid, multicystic or unicystic forms and originate from odontogenic epithelium and exhibit a variety of histological patterns. Keratoameloblastoma is considered to be a rare variant of ameloblastoma associated with more intense keratinization. Therefore, in this present review, authors report a case of keratoameloblastoma in a 14-year-old male and review giving a sneak-peek into this lesion with insight into the literature concerning its presentation, incidence, aetiology, clinical features, radiological appearance, histopathological findings and treatment options along with the current literature about this lesion.

Ameloblastomas (AM) are locally aggressive tumors, with hemangiomatous ameloblastoma (HA) being a rare subtype characterized by vascular proliferation, predominantly in the stroma but occasionally within the epithelial component. We report a case of a 32-year-old male with recurrent mandibular swelling, histopathologically diagnosed as unicystic HA, showing vascularity in both stroma and odontogenic epithelial islands with GLUT1 positivity in the latter. A review of 31 cases revealed a male predilection, mandibular dominance (89.74 %), and overlap with conventional AM features. Vascularity in HA is attributed to reactive, neoplastic, or angiogenic mechanisms, with rare epithelial involvement suggesting aberrant angiogenesis or vascular mimicry. Further research is essential to clarify its pathogenesis and clinical implications.

Primary intraosseous carcinoma (PIOC) is a rare and challenging jawbone malignancy often linked to odontogenic cysts. With minimal connection to oral mucosa and a low incidence rate, PIOC presents significant diagnostic difficulties, often mimicking other odontogenic lesions. Histogenesis and the correct classification of the lesion remains debated, with theories suggesting origins from odontogenic epithelium or cysts. Chronic inflammation may contribute to malignant transformation, though genetic predispositions could also play a role in the pathogenesis. This review underscores the current knowledge of the lesion with the need for standardized diagnostic markers and an enhanced understanding of PIOC origin to improve diagnostic accuracy and treatment outcomes.

Ameloblastoma represents a rare and locally aggressive odontogenic neoplasm, notable for its histopathological diversity. Among its subtypes, the desmoplastic and plexiform variants are relatively rare, with the hybrid form, encompassing both architectural patterns, representing an even more exceptional entity. This article delineates the clinical, radiological, and histopathological profile of a 45-year-old male presenting with pain persisting over the past month in the right posterior maxillary region. Radiographic imaging displayed a mixed radiolucent-radiopaque lesion with poorly demarcated margins, indicative of an aggressive pathology. Histopathological examination revealed a hybrid ameloblastoma, juxtaposing desmoplastic zones with densely fibrotic stroma and classic plexiform sections with epithelial strands in a reticular configuration. This unique hybrid variant underscores the complexity of ameloblastomas and necessitates comprehensive histopathological assessment, as radiological interpretations may prove insufficient for accurate diagnosis. Such detailed analysis contributes to understanding the biological behavior of this rare form, underscoring the need for heightened clinical awareness and continued investigative focus.

Ameloblastoma is a true benign odontogenic epithelial tumor, primarily arising in the jaw, and ranks as the second most prevalent odontogenic neoplasm following odontoma. Known for its diverse clinical, radiographic, and histological manifestations, ameloblastoma encompasses a wide spectrum of presentations. Unicystic ameloblastomas (UAs), a less common and generally less aggressive variant, appear as cystic lesions that can mimic ordinary jaw cysts in their clinical and radiologic features. However, histological examination reveals a distinctive odontogenic epithelium lining the cyst cavities, with some cases exhibiting luminal and mural growth. This article presents a unique case involving a 40-year-old female patient who experienced swelling in the right posterior maxilla for four months. Initially presumed to be a routine ameloblastoma, subsequent histopathological analysis identified it as an intraluminal type of UA with rare plexiform changes. It is characterized by a cystic space lined with ameloblast-like cells in a plexiform arrangement, setting it apart from other UA subtypes. Imaging often reveals a unilocular cystic appearance, which may obscure differential diagnosis by closely resembling other odontogenic cysts. The variations within ameloblastoma have always sparked considerable discussion, and we aim to elucidate the reasons behind this specific transformation and its distinctive characteristics.

Background: Targetoid hemosiderotic hemangioma (THH), also known as hobnail lymphatic malformation (HLL) or hobnail hemangioma, is an uncommon, acquired vascular lesion with a dynamic presentation and an unclear etiology. It predominantly affects adults with an age range from 9 to 78 years and has no gender predilection. The lesion is thought to arise from trauma, leading to micro-shunts between small lesional capillaries and adjacent lymphatic vessels.

Methods: This review article examines the clinical, histologic, and immunohistochemical characteristics of THH, and explores its differential diagnoses, including Kaposi's sarcoma, solitary angiokeratoma, retiform hemangioendothelioma, and Dabska tumor.

Results: THH presents clinically as asymptomatic, well-circumscribed lesions with a central red-blue and/or brown papule surrounded by a peripheral ecchymotic ring, giving a "bull's-eye" or targetoid appearance. Histologically, THH exhibits dilated vascular channels lined by hobnail endothelial cells, red blood cell extravasation, hemosiderin deposition, and mild lymphohistiocytic infiltrates. Immunohistochemistry is positive for D2-40, a lymphatic endothelial marker.

Conclusions: Heightened awareness of the clinical appearance of these solitary targetoid lesions is important. Without clinical-pathologic correlation, the branching telangiectatic vessels and purpura seen in THH could suggest more concerning vascular lesions like Kaposi sarcoma.