Seminars in Diagnostic Pathology最新文献

The aim of this review is to provide the surgical pathologist an overview of lobular lesions, from in situ to invasive carcinoma and the variants, by discussing the epidemiology, clinical characteristics, morphology, immunohistochemistry, known molecular data as well as the treatment recommendations. The recognition of histologic variants of both in situ and invasive lobular carcinoma has expanded the differential diagnosis. Awareness of these different entities is important as treatment recommendations continue to evolve.

Adenoid ameloblastoma (AA) is a rare benign but locally aggressive odontogenic tumor originating from the remnants of the dental lamina or enamel organ. It was newly incorporated into the 2022 WHO classification of odontogenic lesions, standing as the sole novel entity in this update. AA is also regarded as a hybrid tumor because of the combination of histological characteristics observed in both adenomatoid odontogenic tumors and ameloblastoma. Clinically, it presents similarly to other ameloblastoma variants, with patients typically exhibiting a painless, slow-growing jaw swelling. However, this subtype is noted for its more aggressive behavior, including a higher recurrence rate and greater local invasiveness. Histopathologically, AA is distinguished by an intricate arrangement of epithelial islands, cords, and strands, generating a cribriform architectural pattern, with peripheral palisading and central stellate reticulum-like formations. Immunohistochemical profiling reveals the expression of epithelial differentiation markers, including cytokeratins, and proliferative markers such as Ki-67, further corroborating its aggressive phenotype. While its precise etiopathogenesis remains obscure, the unique histological characteristics imply a potentially distinct underlying molecular pathway. Due to its aggressive nature, AA necessitates meticulous clinical and histopathological evaluation and tailored therapeutic strategies to mitigate recurrence risks and optimize patient prognoses. Furthermore, this review integrates histological and molecular insights from recent studies conducted after its inclusion in the updated WHO classification.

Salivary gland-like tumors of the breast are rare neoplasms that share morphologic, immunophenotypic, and/or genetic features with their salivary gland counterparts, highlighting a shared underlying histopathogenesis in most cases. Salivary gland-like carcinomas included in the World Health Organization classification of breast tumors are adenoid cystic carcinoma, secretory carcinoma, mucoepidermoid carcinoma, acinic cell carcinoma, and the exceedingly rare polymorphous adenocarcinoma. These carcinomas are usually triple negative for estrogen receptor and progesterone receptor expression and HER2 overexpression, yet generally have favorable prognosis, in contrast to high-grade triple negative carcinomas of no special type. On the other hand, a small subset, such as solid-basaloid adenoid cystic carcinoma, rare high-grade carcinomas, and those associated with transformation to other types of high-grade invasive carcinoma can behave more aggressively. Other salivary gland-like tumors of the breast, such as pleomorphic adenoma and adenomyoepithelioma, are usually benign but can rarely undergo malignant transformation. Although clinical experience with salivary gland-like breast tumors is overall limited, their recognition and accurate classification has important implications for prognosis and clinical management, especially to avoid overtreatment of salivary gland-like carcinomas. The identification of characteristic genetic alterations and/or immunohistochemical surrogates in many of these tumors has practical applications to establishing an accurate diagnosis and directing clinical management. This review highlights the histopathologic and genetic characteristics of salivary gland-like breast tumors and the implications of the diagnosis for current clinical management.

Odontogenic lesions are a category of lesions, which are found to be arising from the remnants of the tooth-bearing tissues of the body, that can be cystic in nature as a result of degeneration or as a result of excessive proliferation of these cells, can result in the formation of odontogenic tumours which are found in gnathic bones in the body. Since their discovery in literature and the explanation provided for their pathogenesis, these lesions have been the subject of debate and controversy amongst researchers as well as practitioners. Thereby, this review has taken into consideration one such odontogenic tumour, Calcifying Cystic Odontogenic Tumour (CCOT), which first were included under the namesake (Calcifying odontogenic cyst) as a sperate subheading under this cyst, but now has been designated under the category of tumours along with various histologic subtypes classified and described henceforth. Although the lesion has been removed in the recent classification, a wide variety of lesions in biphasic form has been reported in the past. Therefore, this present review takes a sneak-peek into this lesion with insight into its presentation, incidence, aetiology, pathogenesis, histopathology and all the controversies surrounding this category of lesion and the current literature about this lesion with proving the fact that this needs to be considered again in the category of odontogenic tumours.

Sclerosing Odontogrenic Carcinoma (SOC) is a recent addition to the category of odontogenic tumours, which was first described by Koutlas et al. in 2008. It was described as primary intraosseous carcinoma with bland cytology, sclerotic stroma with presence of local infiltration showing aggressive behaviour. Following its discovery and the presentation of first case, only a handful of cases have been reported till date, which may be due to underreporting of the cases or inclusion of the case to other diagnosis since the features of this tumour overlaps with many other lesions of the oral cavity. Due to this factor, the pathogenesis of this category of tumours still remains enigmatic. The clinical features as a result of this factor are also not reported of the consistent type and overlaps with the already existing clinical features of other lesions. This lesion has only appeared till date twice in WHO classification of Odontogenic Cysts and Tumours. Thereby, the literature on this category is still in paucity. Therefore, the present review takes into account all of the features, diagnostic criteria and the markers discovered for this lesion and would provide an insight into whether this lesion is justified as a malignant lesion or should not be considered as a separate category of odontogenic tumour.

The calcifying odontogenic cyst (COC) is an uncommon developmental odontogenic cyst, the oral counterpart of Malherbe's cutaneous calcifying epithelioma (pilomatricoma). This article presents two unique cases of calcifying odontogenic cysts each exhibiting distinctive histopathological features and its literature review. One case with an unexpected finding of cholesterol granuloma (CG), a rare occurrence in non-inflammatory cysts within an unusual location between two maxillary central incisors. One more instance involves the presence of a compound odontome in conjunction with COC. The cases underscore the clinical and histopathological diversity of COC and highlight the importance of radiological and histopathological assessments for accurate diagnosis. The unexpected association of COC with cholesterol granuloma challenges traditional diagnostic expectations. Additionally, the second case suggests that COCs may warrant sub-categorization to better understand their varied presentations and biological behavior. This article contributes to the expanding knowledge of COC, emphasizing the significance of documenting rare cases to enhance comprehension of its nature, pathogenesis, and oral cavity origin.

For many years, odontogenic tumors have been known to present both clinical and histopathological challenges due to their origins in the epithelial, ectomesenchymal, and/or mesenchymal components of tooth-forming tissues. Gaining a comprehensive understanding of both common and rare odontogenic tumors is crucial for their effective study and clinical management. One particularly puzzling tumor is the "plexiform ameloblastoma," a variant of the solid multicystic ameloblastoma. This term describes a distinct pattern of epithelial proliferation within the cystic cavity. Numerous studies have emphasized the variability of the stromal component, further highlighting the enigmatic nature of ameloblastoma. The presence of unique and rare features, such as primitive, mature desmoplastic, hemangiomatous, or ghost cells within the stroma of plexiform ameloblastoma, underscores the differentiation potential of the neoplastic odontogenic epithelium and offers significant insights into the tissue reactions associated with this condition. This case review discusses four instances of plexiform ameloblastoma, illustrating various atypical stromal changes and their influence on patient prognosis. It also provides important criteria for analyzing stromal alterations related to this complex odontogenic tumor.