Head & Neck Pathology最新文献

Objective: To evaluate the influence of MMR complex protein immunoexpression on disease-free survival in oropharyngeal SCC treated non-surgically.

Materials and methods: 85 cases of oropharyngeal SCC diagnosed and treated at the Ceará Cancer Institute were surveyed, from which clinical-pathological data and paraffin blocks of incisional biopsies were retrieved for immunohistochemical reaction for MSH2, MSH6, PMS2, MLH1 and p16. Disease-free survival was calculated and Kruskal-Wallis and Friedman/Dunn tests, chi-square and Fisher's exact, Log-Rank Mantel Cox and Cox regression were performed.

Results: In p16- tumors, loss of MSH2 expression was associated with shorter disease-free survival (p = 0.035) and mean MSH6 expression was significantly higher than MSH2 (p = 0.001). Loss of MSH2 expression in p16 + tumors was associated with longer disease-free survival compared to p16- tumors. Imbalance in the MSH6/MSH2 ratio in p16 + tumors was associated with longer survival compared to p16- tumors. MLH1/PMS2 imbalance was significantly higher in p16 + with recurrence (p = 0.003). Low MSH2 immunoexpression increased the risk of relapse by 9.10 times (CI95% 1.99 to 83.06).

Conclusion: Microsatellite instability in oropharyngeal SCC is demonstrated by the association between loss of protein expression and its heterodimer imbalance with disease-free survival. It was demonstrated that the imbalance of the MMR complex can consequently lead to resistance to treatment and a decrease in disease-free survival in p16 + oropharyngeal SCC tumors.

Purpose: BSND is a chloride channel subunit that is expressed in the normal salivary gland. We aimed to validate the utility of BSND immunohistochemistry in the differential diagnosis of oncocytic salivary gland neoplasms.

Methods: BSND immunohistochemistry was performed in a retrospective cohort of 93 salivary gland lesions, enriched with tumors with oncocytic features and histologic variants of mucoepidermoid carcinoma (MEC).

Results: All oncocytomas (n = 18) showed diffuse membranous BSND immunopositivity. Warthin tumors (n = 18) were also positive for BSND, but the staining pattern was patchy cytoplasmic and membranous in 10-25% of tumor cells. Using a threshold of 10% BSND-positive cells, all Warthin tumors were positive, while none of Warthin-like MECs or non-MEC salivary tumors were positive. Applying the same 10% positivity criterion, two oncocytic MECs were positive for BSND. The percentage of BSND staining in oncocytic MECs was up to 20%. In contrast, BSND was diffusely positive in oncocytomas with a median percentage of positivity of 95% (range: 40 - 100%). Therefore, a higher threshold of > 20% BSND-positive cells may be considered when differentiating between oncocytoma and oncocytic MEC.

Conclusion: BSND immunohistochemistry is a potentially useful diagnostic marker for salivary gland neoplasms, especially oncocytic and Warthin-like MECs. A threshold of ≥ 10% positivity can differentiate Warthin tumors from Warthin-like MECs, whereas > 20% positivity can be effective for separating oncocytomas from oncocytic MECs.

A 41-year-old woman presented with a facial asymmetry in the mental region and a painful, well-circumscribed, tender mass in the right lower buccal vestibule, associated with extensive ill-defined bone rarefaction with subtle cortical bone resorption. Microscopically, a proliferation of bland spindle cells interspersed with collagen fibers and prominent staghorn-like blood vessels was observed. Immunohistochemical analysis revealed strong positivity for CD34, Bcl-2, CD99, and STAT-6, confirming the diagnosis of Solitary Fibrous Tumor (SFT). Conservative surgical enucleation was performed, and 4 years later, recurrence was observed with extensive bone involvement and moth-eaten margins resembling a malignant tumor. SFT is a distinctive spindle cell tumor of fibroblastic differentiation, characterized by prominent branching staghorn-like vessels and a specific NAB2::STAT6 gene fusion. We herein contribute with a central SFT of the mandible with recurrent behavior and radiographic appearance suggesting malignancy.

Jaw osteosarcoma (JOS) is a rare, distinct variant that differ from long bone osteosarcoma (LBOS) in several aspects. JOS typically appears about twenty years later than LBOS, displays a lower propensity for metastasis to other organs, and exhibits better survival rates. The dissimilarities in clinical and biological behavior between JOS and LBOS are likely due, at least in part, to variations in their respective microenvironments. In this report, we present a case of OS affecting the mandible in a young patient. This case displayed classic radiographic features but a unique histopathological presentation, posing a diagnostic challenge for pathologists, especially if encountered in small biopsies.

Purpose: A major problem in establishing treatment strategies for salivary gland carcinomas is the difficulty of preoperative histologic subtyping. Core needle biopsy (CNB) allows the collection of a small, intact specimens from the tumor center for detailed analysis. We evaluated the efficacy and limitations of preoperative diagnosis with CNB specimens collected using a newly developed 20-gauge needle designed to popularize its use.

Methods: Paired preoperative CNB and surgical specimens from 41 patients with malignant salivary gland tumors were retrospectively reviewed. A histologic typing platform, including morphologic and immunohistochemical evaluation and fluorescence in situ hybridization, was evaluated using CNB specimens. Biopsy specimen quality, diagnostic accuracy, and immunohistochemistry concordance rates between biopsy and surgical specimens were analyzed.

Results: In 39 of the 41 patients, CNB provided high-quality specimens, enabling adequate morphologic, immunohistologic, and genomic analyses. In two patients, high-quality CNB specimens could not be obtained due to cystic fluid and tumor firmness. The overall accuracy of correct preoperative diagnosis was 75%. The success rate of histologic subtyping and HER2 immunostaining concordance between CNB and surgical specimens was lower in carcinoma ex-pleomorphic adenoma (CXPA) than in de novo carcinoma (histologic subtyping; CXPA vs de novo carcinoma 50% vs 89%, p = 0.016, HER2 concordance; salivary duct carcinoma [SDC] ex-PA vs de novo SDC 16% vs 100%, p = 4.66E-03). No recurrence occurred due to tumor seeding after CNB.

Conclusions: Highly accurate histologic subtyping of salivary gland carcinomas can be performed by preoperative CNB; however, specificity can be more challenging in pathologically heterogenous tumors.

Purpose: Adenoid cystic carcinoma (AdCC) of the head and neck harbors MYB/MYBL1::NFIB fusions in around 60% of cases, with unfavorable long-term survival due to frequent recurrences and metastases, currently lacking effective targeted therapy. The study aims to identify actionable alterations and to elucidate the molecular underpinnings of MYB/MYBL1::NFIB-negative AdCC using a large targeted RNA sequencing panel.

Methods and results: We retrospectively searched our MSK-Solid Fusion clinical sequencing database for head and neck AdCC sequenced between 2016 and 2023. Of a total of 55 cases, 28 showed MYB::NFIB, 7 showed MYBL1::NFIB, and one case each harbored MYB::MPDZ (case 1) and FUS::MYB (case 2). One base of tongue tumor expressed both MYB::NFIB fusion and MET exon 14 skipping transcripts due to concurrent MET splice site mutation, D1010N (case 3). One parotid tumor lacked MYB/MYBL1 rearrangement but instead showed an in-frame SEC16A::NOTCH1 fusion that preserved the secretase cleavage site (case 4). Clinical records on 4 cases with non-canonical sequencing findings were reviewed. Distant metastases were present at the initial diagnosis (case 2) or at recurrence (cases 1, 3, and 4). Disease-related mortality occurred in cases 2 and 4 despite radiotherapy and immunotherapy.

Conclusions: The study improved the understanding of AdCC providing the first documentation of tumor clinical behavior associated with MYB::MPDZ and FUS::MYB fusions and reporting potentially actionable SEC16A::NOTCH1 fusion and MET exon 14 skipping mutation. Further research is needed to explore the therapeutic utility of MET inhibition and the efficacy of γ-secretase inhibitors against rare NOTCH1 fusions in AdCC.

Purpose: Salivary gland malignancies may have overlapping architectural patterns, tumor morphology, and immunohistochemical phenotypes, presenting challenges in precise classification. Molecular phenotyping has become quite useful for providing an additional diagnostic modality, and potential drug targets. Here we reported a young female patient with salivary gland tumor of the tongue base harboring genetic alterations by next generation sequencing (NGS).

Methods: The morphological, immunohistochemical and molecular features of this case were described, and related literature was reviewed.

Results: The tumor showed an epithelial myoepithelial architecture arranged in cords and tubules interwoven with a chondromyxoid stroma, along with perineural invasion and adjacent striated muscle infiltration. Myoepithelial cells were positive for CK5/6, partially positive for P63 and CK7, and sporadically positive for S100. Immunoprofiling revealed a low density of infiltrating lymphocytes and macrophages and the absence of programmed death ligand 1 (PD-L1). Notably, RNA-based NGS showed EWSR1::BEND2 gene fusion in this tumor, and EWSR1 break-apart was confirmed by fluorescence in situ hybridization. This led to a final diagnosis of a minor salivary gland malignancy with EWSR1::BEND2 fusion. Only two other cases of salivary gland tumors with EWSR1::BEND2 fusion had been previously reported, which were also detected via RNA-based NGS.

Conclusion: This study emphasized that EWSR1::BEND2 fusion may drive the carcinogenesis in salivary glands neoplasia. In clinic RNA-based NGS could be essential for precise genotyping of EWSR1 fusion in this rare disease.

Eosinophils are often encountered in the stroma and peritumoral microenvironment of squamous cell carcinomas. Because eosinophils are readily identified on routine hematoxylin and eosin stained sections, researchers have explored multiple ways in which identifying the extent of eosinophil infiltration on routine biopsy and excisional specimens might provide diagnostic and prognostic information. We review the literature on this evolving topic.

Objective: This study aimed to implement and evaluate a Deep Convolutional Neural Network for classifying myofibroblastic lesions into benign and malignant categories based on patch-based images.

Methods: A Residual Neural Network (ResNet50) model, pre-trained with weights from ImageNet, was fine-tuned to classify a cohort of 20 patients (11 benign and 9 malignant cases). Following annotation of tumor regions, the whole-slide images (WSIs) were fragmented into smaller patches (224 × 224 pixels). These patches were non-randomly divided into training (308,843 patches), validation (43,268 patches), and test (42,061 patches) subsets, maintaining a 78:11:11 ratio. The CNN training was caried out for 75 epochs utilizing a batch size of 4, the Adam optimizer, and a learning rate of 0.00001.

Results: ResNet50 achieved an accuracy of 98.97%, precision of 99.91%, sensitivity of 97.98%, specificity of 99.91%, F1 score of 98.94%, and AUC of 0.99.

Conclusions: The ResNet50 model developed exhibited high accuracy during training and robust generalization capabilities in unseen data, indicating nearly flawless performance in distinguishing between benign and malignant myofibroblastic tumors, despite the small sample size. The excellent performance of the AI model in separating such histologically similar classes could be attributed to its ability to identify hidden discriminative features, as well as to use a wide range of features and benefit from proper data preprocessing.