Head & Neck Pathology最新文献

DEK::AFF2 fusion-associated papillary squamous cell carcinoma is a recently characterized sinonasal malignancy defined by its unique translocation. DEK::AFF2 carcinomas may be deceptively monotonous and lack keratinization, resembling transitional epithelium. The lack of traditional cytological atypia presents diagnostic challenges. Our case describes the first report of fine-needle aspiration cytology of a lymph node involved by DEK::AFF2 carcinoma in a patient with previously resected sinonasal inverted papilloma with carcinomatous transformation six years prior to presentation. This aspirate consisted of a lymphoid-rich background admixed with a moderate amount of epithelial cells arranged in cohesive structures of variable size, including large sheets. The tumor cells resembled those of the corresponding biopsy, featuring mildly hyperchromatic nuclei with fine to vesicular chromatin. Lesional cells lacked keratinization, mitoses, or hyperchromasia. Our finding suggests that in nodal aspirates of patients with a history of sinonasal-type papillomas, especially those with prior malignant transformation or atypia, there should be consideration for the possibility of DEK::AFF2-related primary. When in doubt, DEK FISH of AFF2 immunohistochemistry should be performed for confirmation.

Warthin's tumor is the second most common neoplasm of the parotid gland and consists of 2 components, including lymphoid stroma and glandular epithelium. Malignant transformation in this tumor is mostly seen in the lymphoid component; however, the carcinomatous transformation of the epithelial component is extremely rare. Cases of latter reported in the literature include squamous cell carcinoma, adenocarcinoma, mucoepidermoid carcinoma, oncocytic carcinoma, Merkel cell carcinoma, and undifferentiated carcinoma. We describe an extremely rare case of salivary duct carcinoma arising in a Warthin tumor in a 64-year-old male. Patient presented with an enlarging left parotid mass, biopsy of which showed salivary duct carcinoma. He subsequently underwent left parotidectomy along with left level II-IV lymph node dissection. Histology revealed both in situ as well as invasive salivary duct carcinoma arising from Warthin tumor. Immunohistochemistry showed tumor cells positive for CK7, AR, and GATA3, while p63 highlighted the myoepithelial cell layer in the in situ component. Her2 was 2+ by immunohistochemistry. In addition, PD-L1 IHC revealed positive expression with a combined positive score of 20%.

Immune checkpoint inhibitors have improved the outcome of patients diagnosed with inoperable recurrent or metastatic head and neck squamous cell carcinoma. However, as only a subset of head and neck cancer patients benefit from this treatment, biomarkers predicting treatment response help guide physicians in their clinical decision-making. PD-L1 expression assessed by immunohistochemistry is the single most clinically relevant biomarker predicting response to PD-1-blocking antibodies. Here, we discuss in which clinical context assessment of PD-L1 expression is instrumental for the choice of therapy, how pathologists score it, and how it affects the approval of anti-PD-1 antibodies. Furthermore, we discuss the heterogeneity of PD-L1 expression and review technical aspects of determining this prominent biomarker-knowledge that might influence clinical decision-making.

Squamous odontogenic tumor (SOT) is a rare benign but locally infiltrative tumor often misdiagnosed as other entities, such as ameloblastoma and squamous cell carcinoma, due to overlapping morphological findings. We document here the clinicopathological and imaging findings of an aggressive intraosseous SOT in the posterior left region of the maxilla in a 25-year-old male patient. On intraoral examination, the tumor extended from the region of the left lateral incisor to the upper left premolar and was covered by reddish mucosa, with discrete areas of ulceration. Imaging exams revealed an osteolytic lesion causing thinning, erosion, and buccal and lingual cortical plate perforation associated with an impacted canine. Microscopically, the tumor showed a proliferation of islands of well-differentiated squamous epithelium in a variably collagenized background. The peripheral cells of the islands were flat or slightly cuboidal and did not exhibit nuclei with peripheral palisade and reverse polarization. The diagnosis of SOT was rendered. The patient underwent surgical resection and has been under clinical follow-up for approximately 12 months with no signs of recurrence. A careful morphological evaluation is essential to avoid misdiagnosis and ensure a satisfactory treatment approach.

Background: Predominantly macrofollicular architecture in invasive encapsulated follicular variant of papillary thyroid carcinoma (IEFVPTC-MF) is rare and often a cause of misinterpretation during pre-operative work-up and histopathology evaluation. We comprehensively evaluated the radiological, cytological, gross, microscopic, molecular and follow-up characteristics of four such cases, intending to increase its recognition and add our experience to the limited literature available.

Methods: All such histopathologically-proven cases of IEFVPTC-MF were retrieved from the departmental archives. The clinical details, thyroid ultrasound, cytology and thyroid scan findings were reviewed. Allele-specific PCR for BRAF p.V600E, KRAS, NRAS, and HRAS mutations, and FISH assays for ETV6::NTRK3 fusion and RET fusions were performed.

Results: There were four cases of IEFVPTC-MF diagnosed between 2021 and 2022, involving two males and two females. The median age at presentation was 27 years, and the duration of the disease was 1-10 years. Thyroid ultrasound was TR1 (benign; n = 1), TR2 (not suspicious; n = 2), or TR4 (moderately suspicious; n = 1). Cytology was categorized as nondiagnostic (n = 1), benign (n = 1), and atypia of undetermined significance (n = 1). The three nodules with available cytology smears showed abundant colloid. Cells were arranged as sheets/microfollicles/clusters. Nuclei were predominantly round with minimal/focal elongation, membrane irregularity, and cellular crowding. On gross examination, cut surfaces of the tumors showed variable amounts of colloid. The tumors were solid-cystic. Histopathology revealed partially encapsulated multinodular tumors. There were prominent pseudopapillae projecting into the lumina of macrofollicles. Nuclei were predominantly round with variable nuclear atypia, including chromatin clearing and multifocal presence of nuclear grooves. Pseudoinclusions were identified in two. Molecular analysis revealed NRAS codon 61 mutation and ETV6::NTRK3 fusion in one case each. Two patients had cervical lymph node and hematogenous metastases. Post-radio-active iodine, the response was structurally incomplete (n = 2), indeterminate (n = 1) and excellent (n = 1).

Conclusions: Macrofollicular architecture in invasive encapsulated follicular variant of papillary thyroid carcinoma is a major pitfall in thyroid oncology practice. Long-standing disease, and ultrasonographic and cytological features that overlap with benign disease, often lead to underdiagnosis during pre-operative evaluation. As patients may consequently develop distant metastases and have inadequate treatment response, there is a need for more vigilant understanding of the spectrum of macrofollicular thyroid disease for accurate diagnosis. ETV6::NTRK3 or other fusions, when found, present opportunities for targeted therapy.

A 56-year-old Brazilian woman sought dental care, presenting with multiple asymptomatic papillomatous lesions with a coalescent pattern and intermingled cobblestone-like clefts along the alveolar ridge and marginal and attached gingivae. Multiple whitish papules were also observed on the face, neck, and limbs. Incisional biopsies of these lesions were performed. Microscopically, the skin lesion revealed epithelial clear cells and intraepithelial keratinization with areas of orthokeratosis, while the gingival lesions showed a parakeratinized stratified squamous epithelium with collagenous connective tissue. These features were consistent with those of a trichilemmoma and fibroepithelial hyperplasia, respectively. This article illustrates a case of Cowden syndrome (CS), a rare multisystem genetic condition in which both cutaneous and mucosal tissues were affected. Fewer than 40 cases of CS with oral involvement affecting middle-aged adults have been documented hitherto.

Background: Altered levels of miRNAs might affect the pathogenesis of oral squamous cell carcinoma (OSCC) and oral potentially malignant disorders (OPMD). This study evaluated the diagnostic potential of salivary miRNA-21 and miRNA-184 in OSCC and OPMD.

Methods: We recruited a total of 90 subjects including OSCC, OPMD, and healthy controls. RNA was isolated from the saliva samples of the study subjects. Expression of miRNA-21 and miRNA-184 was analyzed using qRT-PCR. Their levels were compared and the diagnostic cut-off was determined using the ROC curve.

Results: There was a significant increase in miRNA-21 and a decrease in miRNA-184 in OSCC and OPMD as compared to healthy controls (p < 0.001). Levels of salivary miRNA-21 and miRNA-184 can differentiate OSCC and OPMD from controls and premalignant conditions from malignant conditions.

Conclusion: Salivary miRNA-21 and miRNA-184 may be beneficial for the early detection of OSCC and OPMD. Also, saliva can be used for detecting neoplastic transformation of oral mucosa since it is non-invasive and easily accessible.

Surgical ciliated cysts, also known as implantation cysts or postoperative maxillary cysts, are uncommon cystic formations predominantly arising in the posterior maxillary region after radical maxillary sinus surgery. Herein, we present the case of a 28-year-old male patient who had previously undergone orthognathic surgery and later experienced a minor car accident without major consequences. Approximately four years after surgery, the patient sought dental care due to the presence of a painless swelling in the maxillary region. Upon intraoral examination, the swelling extended from the area around the right canine to the upper left molar, covered by red mucosa. Image studies revealed an extensive well-defined osteolytic lesion causing thinning, erosion, buccal cortical plate perforation, and root resorption. An incisional biopsy was performed, and microscopic examination revealed a cystic lesion lined by ciliated respiratory-type epithelium and capsule variably fibrotic with sparse chronic inflammation. The final diagnosis was surgical ciliated cysts. The treatment approach involved decompression followed by enucleation and curettage, with the addition of bone grafting and the application of Leukocyte-Platelet Rich Fibrin (L-PRF). The patient has been under clinical follow-up for approximately 17 months with no signs of recurrence. A careful morphological evaluation is essential to avoid misdiagnosis and ensure a satisfactory treatment approach. In conclusion, this case highlights the importance of accurate diagnosis and appropriate treatment approaches for surgical ciliated cysts to ensure favorable patient outcomes.

Background: The study aims to analyse the non-calcifying/Langerhans cell rich (NCLC) subtype of calcifying epithelial odontogenic tumour (CEOT).  METHOD: The features of cases of the NCLC subtype of CEOT noted in the English literature by PubMed as well as 3 new cases were reviewed.

Results: Overall, twenty-one cases were noted. Many were women in the fourth to sixth decades (male-to-female ratio =1 to 2). Radiologically, the lesion is often unilocular with resorption of the affected teeth. Nineteen of the 21 cases occurred in the maxilla, especially the anterior portion. On pathological examination, epithelial cells are noted in non-calcifying amyloid-rich fibrous stroma. The main differential diagnosis is the amyloid subtype of central odontogenic fibroma. Immunohistochemical studies revealed the tumour epithelial cells were positive for cytokeratins and p63 and contained CD1a, S-100, and langerin-positive Langerhans cells. On a median follow-up of 2 years, one patient had a recurrence one year after curettage.

Conclusion: The NCLC subtype of CEOT is unique as it contains significant numbers of Langerhans cells and has clinicopathological features distinctive from classic CEOT.