Head & Neck Pathology最新文献

Background: Transdifferentiation of hairy cell leukemia to histiocytic sarcoma (HS) has not been previously reported in the head and neck. Given the rarity of HS, it can pose a challenge to diagnose this aggressive malignancy.

Case presentation: A 93-year-old male with a complex medical history presented with symptomatic and mobile lower anterior teeth. No intraoral growth mass was present initially and radiographic examination showed a radiolucent lesion in the anterior mandible. An incisional biopsy under local anesthesia was performed and histopathologic examination revealed a malignant sarcoma which upon further clinical, immunohistochemical, and molecular workup, confirmed the diagnosis.

Diagnosis: Initial histopathologic evaluation of the biopsy rendered a provisional diagnosis of undifferentiated pleomorphic sarcoma. The case was referred to a tertiary care center for complete medical workup and additional ancillary studies where it was definitively diagnosed as a HS. The patient passed away a month after this HS diagnosis.

Background: This systematic review (SR) aimed to summarize the clinical, histopathological, and immunohistochemical features of low-grade myofibroblastic sarcoma (LGMS) in the oral and maxillofacial region (OMR), as well as treatment protocols, recurrence, follow-up, and metastasis rates. It follows PRISMA 2022 guidelines and is registered in PROSPERO (CRD42023409758).

Methods: An electronic search included PubMed, EMBASE, Scopus, Web of Science, LILACS, Google Scholar, and ProQuest databases, and bias risk was assessed using the Joanna Briggs Institute tool. Statistical analyses, including Fisher's and Chi-Squared tests, were conducted to explore associations between clinical variables, and survival analysis was performed using the Kaplan-Meier method.

Results: Forty-three studies covering 78 cases were included. LGMS showed a slight female predominance (51.28%) and an average patient age of 35.35 years. The most affected sites were the mandible (29.4%), maxilla (19.23%), and tongue (15.38%). Clinical presentations included masses (30.76%), tumors (26.92%), and swelling (12.82%), with symptom duration ranging from 1 week to 30 months. Surgery alone was the primary treatment (60.25%), with recurrence in 20.51% and metastasis in 5.12% of cases. One-year and 5-year overall survival rates were 92.6% and 71.8%, respectively. Surgery as the sole treatment was significantly associated with a lower metastasis rate (p = 0.005).

Conclusion: Our findings highlighted the importance of considering LGMS in differential diagnoses of myofibroblastic lesions and underscored the need for a comprehensive immunohistochemical analysis. Complete surgical excision remains the preferred treatment, though long-term follow-up is needed to better understand recurrence and metastasis risks.

Purpose: Skull base osteosarcoma is an exceedingly rare malignancy. Unlike maxillofacial osteosarcomas, there are only few cases of skull base tumors reported in literature, and their clinical behavior and treatment outcome are not well defined. This study aims to characterize the clinical features and outcomes of primary skull base osteosarcoma based on our experiences of 9 cases and to review available literature data.

Methods: A retrospective analysis was done on 9 cases of skull base osteosarcoma diagnosed at IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy, from 1995 to 2023. Clinicopathologic features were reported, and survival outcomes were analyzed. Literature review was performed by searching the PubMed database for published cases of skull base osteosarcoma. Kaplan-Meier survival analysis was used to calculate 1-year, 3-year, and 5-year survival rates.

Results: Patients were 5 males and 4 females, with an age range of 5-72 years (mean: 39 years). Tumor location was frontal (3), sphenoid/ethmoid (3), occipital (2), and temporal (1) bone. Seven patients had subtotal resections; Two had total resection, but only one achieved negative margin. Follow-up duration ranged from 4 to 256 months (median: 28 months). Local recurrence occurred in 4 patients. At last follow-up, 5 patients were alive, with 3 had no evidence of disease (NED) and 2 alive with disease (AWD), while 4 patients died of disease (DOD). One-year, 3-year, and 5-year survival were 88.9%, 76.2%, and 57.1%, respectively. Literature review showed 1-year, 3-year, and 5-year survival of 50.3%, 22.6%, and 6.7%, respectively.

Conclusion: Skull base osteosarcoma is a rare malignancy with limited data on its clinical behavior. Surgical resection with negative margins is critical for better outcomes but is challenging due to the complex anatomy. Multidisciplinary treatment approaches are essential to improve our understanding of the tumor and survival outcomes.

Purpose: The term "metatypical" is anecdotally employed to describe histopathological variations that can be found in salivary gland adenoid cystic carcinoma.

Methods: A 68-year-old man presented with a painful palatal nodule developed over the period of 6 months. A cone beam computed tomography showed a soft tissue-based mass with penetration into maxillary bone. An incisional biopsy was performed.

Results: The histopathology revealed a biphasic tumor predominantly composed by myoepithelial-type basaloid cells arranged in trabeculae and macrocysts with focal squamous differentiation. Occasional intervening ducts were observed. Immunohistochemical reactions highlighted the myoepithelial nature of basaloid cells, which were positive to cytokeratin 14 and smooth muscle actin, whereas the duct-forming cells were positive to cytokeratin 7 and cytokeratin 14. A small focus of conventional cribriform adenoid cystic carcinoma was identified at the periphery of the specimen. The diagnosis of metatypical adenoid cystic carcinoma was established CONCLUSIONS: The morphological diversity of metatypical adenoid cystic carcinoma represents a potential diagnostic pitfall in surgical pathology practice, particularly if the metatypical components are predominant and overlap the conventional areas. The list of differential diagnoses to be considered includes benign and malignant salivary and odontogenic tumors, but the adequate tumor classification is fundamental to ensure an appropriate treatment strategy for a long-term disease control.

Introduction: Oral lichen planus (OLP) and oral lichenoid lesions (OLL) are considered potentially malignant oral disorders, presenting with similar clinical and histopathological manifestations that make differential diagnosis difficult and reinforce the need for new techniques for their evaluation.

Objective: This study aimed to compare the histomorphometric characteristics of OLP and OLL.

Methodology: This retrospective cross-sectional study was based on 30 histological sections of incisional biopsies of OLP and OLL stained with hematoxylin-eosin for the analysis of morphological parameters, such as keratosis, acanthosis, inflammatory infiltrate band, eosinophilic band, degeneration of the basal layer, involvement of the epithelium-chorion interface, and degree of subepithelial inflammatory infiltrate; and morphometric parameters, such as keratin thickness, distance from the basal layer to the epithelial surface, and thickness of the inflammatory infiltrate band. Chi-square and Fisher's exact tests were used to compare categorical variables and injury types. The t-test was used to compare morphometric variables between the two types of injury.

Results: There was no significant association between the type of lesion and the clinical characteristics of the patients (p > 0.05). The degree of dysplasia, used as an inclusion criterion, was associated with lesion type (p = 0.0003). There were no significant differences between the morphometric variables evaluated for the two types of lesions (p > 0.05).

Conclusion: Based on the methodology used and the sample established for this study, there were clinical and histomorphometric similarities between OLP and OLL. This justifies further discussion on whether these lesions are a spectrum of presentations of the same condition or truly distinct conditions.

Background: SMARCB1-deficient and SMARCA4-deficient sinonasal carcinomas are rare, with only a few systematic studies available in the literature. Secondary EWSR1 gene abnormalities have been reported in SMARCB1-deficient tumors. This study aimed to systematically investigate SWI/SNF complex-deficient sinonasal carcinomas in a single-institution cohort, perform clinicopathologic characterization, and explore the underlying molecular mechanisms.

Method: Immunohistochemistry (IHC) of INI1 and BRG1 was performed on tissue microarrays containing tumor tissue from 149 consecutive sinonasal carcinomas. Single nucleotide polymorphism (SNP) array and EWSR1 gene fluorescence in situ hybridization (FISH) analyses were conducted on SMARCB1-deficient sinonasal carcinomas. Clinicopathologic characterization was studied.

Result: Of the 149 sinonasal carcinomas, 7 (4.7%) showed SMARCB1 loss, while none demonstrated SMARCA4 loss. All patients were male and presented with advanced-stage tumors. Four SMARCB1-deficient sinonasal carcinomas exhibited basaloid morphology, two displayed eosinophilic tumor morphology, and one had mixed morphology. Homozygous and heterozygous SMARCB1 deletions were identified in 4/6 and 2/6 cases respectively. Heterozygous loss involving genes neighboring SMARCB1 gene, including EWSR1, was observed in four cases. One tumor showed a heterozygous loss of the entire chromosome 22q. EWSR1 FISH assay revealed concordant heterozygous EWSR1 loss in these five cases.

Conclusion: SMARCB1-deficient carcinomas account for 4.7% of sinonasal carcinomas in this single-institution cohort, while SMARCA4-deficient tumors are even rarer, with none identified. SMARCB1-deficient sinonasal carcinomas exhibit a broad spectrum of morphologic and immunohistochemical features. These carcinomas show complex genetic alterations, with homozygous SMARCB1 deletions present in the majority of cases.

The primordial odontogenic tumor (POT) is a rare mixed odontogenic tumor believed to develop during early odontogenesis. It is composed of a fibromyxoid stroma with proliferation of mesenchymal cells surrounded by a layer of columnar cells exhibiting reverse polarity and pale cytoplasm. This article presents a case of primordial odontogenic tumor in the anterior region of the mandible of a 10-year-old male Caucasian patient who presented with an expansive intraosseous lesion in the anterior portion of the mandible and a delay in tooth eruption, with a 1-year history of asymptomatic swelling. An incisional biopsy was performed and sent to an external pathology service that diagnosed as ameloblastoma. The clinician sent the paraffin block and hematoxylin/eosin (H&E) slides for diagnosis review to the University of São Paulo, Oral Pathology Service. The H&E slides revealed an abundant myxoid cell-rich stroma containing a few islands of ameloblastic-like epithelium and areas of loosely arranged stellate/spindle-shaped cells resembling stellate reticulum. The odontogenic-like epithelium was also noted at the periphery of the specimen, as well as discrete areas of hyalinization. Cellular pleomorphism and mitotic figures were not observed, supporting the diagnosis of ameloblastic fibroma. The clinician proceeded with surgical excision and sent us the whole specimen. After reviewing the slides and discussing the case, the final diagnosis was primordial odontogenic tumor. This report is relevant to provide more information for clinicians and pathologists about this rare entity.

Background: Noonan syndrome (NS) is a developmental malformation condition in the RASopathies group, characterized by variable clinical and molecular features. The syndrome is genetically heterogeneous, with the most frequent mutation found in approximately 50% of cases occurring in the PTPN11 gene. NS is reported to be associated with neurogenic, hematopoietic, melanocytic and other visceral malignancies, but osteosarcoma development has not been reported in association with NS.

Case report: Therefore, we report the first case of a male with NS who developed osteosarcoma of the mandible in a background of long-standing polyostotic fibrous dysplasia (FD) of the craniofacial bones.

Purpose: This systematic review summarizes the current literature on Warthin-like mucoepidermoid carcinoma (WL-MEC), highlighting its clinicopathological, immunohistochemical and molecular characteristics.

Methods: This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and was registered by PROSPERO (protocol CRD42024523598). Case reports and case series published in English on WL-MEC of major and minor salivary glands were included. The search was conducted in MEDLINE/PubMed, Scopus, Web of Science, and Embase databases in November 2024, along with a search in grey literature. Twenty-one articles met the eligibility criteria. The extracted information included clinicopathological data, immunohistochemical and molecular tests, treatment, recurrence, metastasis, follow-up, and status. The data analysis was performed descriptively, and presented as absolute and relative frequencies, and means or median for numerical variables.

Results: 78 WL-MEC cases were analyzed, with a female predominance observed and a wide age range, peaking in the sixth decade of life. Most cases involved the parotid gland and presented as indolent nodular masses, often asymptomatic. Histologically, the majority were low-grade tumors, with multicystic growth patterns and a lymphocytic infiltrate. Immunohistochemical analysis revealed consistent expression of p63, p40, CK5/6, and exhibited low Ki67 proliferation index (< 5%). MAML2 rearrangement was identified in all molecularly analyzed cases (n = 72/ 100%). Surgical treatment was the most common approach, which typically resulted in low recurrence rates, no distant metastasis, and favorable overall outcomes.

Conclusion: WL-MEC cases typically present as indolent, asymptomatic nodules in the parotid gland, often with a female predominance and a wide age range, peaking in the sixth decade of life. Surgery is the primary treatment and is associated with a favorable prognosis, characterized by low rates of recurrence and metastasis. These tumors commonly exhibit low-grade histopathological features, a multicystic pattern, and lymphocytic inflammatory infiltrate. The detection of MAML2 rearrangement, typically via FISH, is an essential diagnostic tool, emphasizing the molecular similarities between WL-MEC and conventional MEC.

Introduction: Ameloblastic fibroma (AF), ameloblastic fibrodentinoma (AFD), and ameloblastic fibro-odontoma (AFO) are rare mixed odontogenic tumors. While some authors propose that some cases may evolve into odontomas, other tumors with aggressive clinical features suggest a neoplastic origin. A subset of AF and AFD/AFO harbor the pathogenic BRAF p.V600E mutation. SOX9, known for its role in the differentiation of various cell types, particularly in chondrogenesis, has not been previously studied in odontogenic tumors. In this study, we report the clinicopathologic features of a large international cohort of AF and AFD/AFO cases and analyze the immunohistochemical expression of BRAF p.V600E and SOX9.

Materials and methods: Clinical and radiographic data were collected from four Oral and Maxillofacial Pathology service archives spanning from 1991 to 2024. Deidentified slides were reviewed by two independent oral pathologists. Immunohistochemical staining for BRAF p.V600E and SOX9 was performed on non-decalcified tissue samples from cases with available specimens.

Results: A total of 62 tumors were identified, including 30 AF cases and 32 AFD/AFO cases. The cohort consisted of 33 male and 29 female patients, with average ages of 15.3 years for AF and 12.3 years for AFD/AFO. Tumors predominantly affected the posterior mandible and appeared as unilocular or multilocular radiolucent or mixed lesions, often causing tooth impaction and cortical expansion, with an average size of 3.7 cm for AF and 2.5 cm for AFD/AFO. Two cases were classified as peripheral AF/AFD. Microscopically, all cases exhibited cellular mesenchymal components resembling dental papilla, with branching strands and islands of odontogenic epithelium. AFD/AFO cases also displayed dental hard tissue, and occasional chondromyxoid differentiation was observed within the stroma. Rare hybrid tumors were identified, including associations with calcifying odontogenic cysts, cemento-ossifying fibroma and central giant cell granuloma. BRAF p.V600E showed cytoplasmic positivity in the mesenchymal component of AF (81%) and AFD/AFO (54%). SOX9 exhibited diffuse nuclear immunoreactivity in both epithelial and mesenchymal components (92%).

Conclusion: This study represents one of the largest well-documented series of AF and AFO/AFD, providing valuable clinicopathologic and immunohistochemical insights. Additionally, the diffuse expression of SOX9 in both epithelial and mesenchymal components suggests a potential role in odontogenic differentiation, a novel finding that may have implications for understanding the histogenesis of these lesions. The aggressive behavior of some AFs and AFD/AFOs in our study supports their classification as odontogenic neoplasms rather than hamartomas.