Head & Neck Pathology最新文献

Metastases in the oral and maxillofacial region, particularly in soft tissues, are exceedingly rare. Such metastases can present as swelling in older individuals, especially in the tongue and gingiva. Furthermore, colorectal metastases at this site are commonly found in the mandible and gingiva and usually share the same morphology as the primary tumor. Herein, we report the case of a 61-year-old woman with a metastatic nodule in the tongue covered by normal mucosa. The clinical, histopathological, and immunohistochemical findings were essential for the final diagnosis of colorectal metastasis, consistent with adenocarcinoma with mucinous differentiation and intestinal phenotype. Metastases of colorectal adenocarcinoma to the tongue are rare but should be included in the differential diagnosis of nodular lesions at this site. The diagnosis can therefore be made based on meticulous clinical and histopathological examination complemented by immunohistochemistry.

Purpose: Radiation therapy is a treatment modality for various ocular and ocular adnexal tumors. The histopathology of chronic radiation dermatitis has been well-described. The authors present two cases demonstrating and characterizing "chronic radiation conjunctivitis" which has not been histopathologically illustrated in detail.

Methods: Retrospective case review of two patients who received proton beam irradiation for an anterior uveal melanoma and external beam radiation for conjunctival lymphoma, and developed leukoplakia and/or thickening of the eyelid margin and symblepharon. Hematoxylin and eosin-stained sections of eyelid margin and conjunctival biopsies as well as clinical histories were reviewed.

Results: Conjunctival biopsies in both cases revealed squamous epithelial metaplasia, chronic inflammation and bizarre-appearing stromal cells with hyperchromatic nuclei in a fibrotic/sclerotic stroma, consistent with chronic radiation conjunctivitis. These stromal cells are believed to be the same "radiation fibroblasts" described in chronic radiation dermatitis.

Conclusion: The radiation fibroblast is characteristic for the diagnosis of chronic radiation conjunctivitis, as it is in radiation dermatitis. Features of squamous metaplasia of conjunctival epithelium, keratinization, subepithelial fibrosis/sclerosis and chronic inflammation are frequently found but not specific. A detailed history and other ancillary tests help differentiate cicatrizing conjunctival conditions, and biopsy should be performed in the setting of suspicion for a secondary malignancy.

Purpose: Mesenchymal neoplasms composed of vascular, smooth muscle, and adipocytic components are uncommon in the nasal cavity. While angioleiomyoma (AL) is a smooth muscle tumor in the Head & Neck WHO classification, it is considered of pericytic origin in the Skin as well as Soft Tissue and Bone classifications. For nasal AL with an adipocytic component, the terms AL with adipocytic differentiation and angiomyolipoma (AML) have been applied, among others. AML is a type of perivascular epithelioid cell tumor (PEComa), most often arising in the kidney, sometimes associated with the tuberous sclerosis complex (TSC). It is uncertain whether nasal cavity AML and AL are best considered hamartomas or neoplasms, as their genetics are largely unexplored.

Methods: We performed a multi-institutional retrospective study of nasal cavity mesenchymal lesions. Patient demographics, clinical histories, and histologic and immunohistochemical findings were collected. DNA and RNA were extracted from formalin-fixed, paraffin-embedded tissue and analyzed by SNP-based chromosomal microarray, targeted RNA fusion sequencing, and whole-exome sequencing.

Results: Fifteen lesions (3-42 mm) were identified, predominantly in male (87%) patients with a median age of 60. Patients typically presented with obstructive symptoms, and none had a history of TSC. One AL was a recurrence from six years prior; 11 cases showed no recurrence (median 4.7 years, range: 0.88-12.4). Morphologically, 11 AML contained 30-80% smooth muscle, 10-25% vasculature, and 2-60% adipose tissue, while four AL contained 70-80% smooth muscle and 20-30% vasculature. Other histologic observations included ulceration, thrombosis, inflammation, myxoid change, senescent nuclei, and extramedullary hematopoiesis; no well-developed epithelioid cell morphology was identified. Immunohistochemically, all cases were positive for smooth muscle markers (actin, desmin, and/or caldesmon) and negative for melanocytic markers. Molecular analysis revealed loss of 3p and 11q in a single AML. No other known pathogenic copy number or molecular alterations were seen, including in TSC1/2, TFE3, or NOTCH2.

Conclusion: Nasal cavity AML lacks morphologic, immunophenotypic, and genetic features of PEComa family AML. The significant histologic overlap between nasal AML and AL without distinguishing molecular features in either entity suggests "sinonasal angioleiomyoma with adipocytic differentiation" may be the most appropriate terminology for hybrid vascular and smooth muscle lesions containing adipocytic components.

Purpose: The current study aimed to investigate the use of surrogate immunohistochemical (IHC) markers of proliferation and stem cells to distinguish ameloblastoma (AB) from ameloblastic carcinoma (AC).

Methods: The study assessed a total of 29 ACs, 6 ABs that transformed into ACs, and a control cohort of 20 ABs. The demographics and clinicopathologic details of the included cases of AC were recorded. The Ki-67 proliferation index was scored through automated methods with the QuPath open-source software platform. For SOX2, OCT4 and Glypican-3 IHC, each case was scored using a proportion of positivity score combined with an intensity score to produce a total score.

Results: All cases of AC showed a relatively high median proliferation index of 41.7%, with statistically significant higher scores compared to ABs. ABs that transformed into ACs had similar median proliferation scores to the control cohort of ABs. Most cases of AC showed some degree of SOX2 expression, with 58.6% showing high expression. OCT4 expression was not seen in any case of AC. GPC-3 expression in ACs was limited, with high expression in 17.2% of ACs. Primary ACs showed higher median proliferation scores and degrees of SOX2 and GPC-3 expression than secondary cases. Regarding SOX2, OCT4 and GPC-3 IHC expression, no statistically significant differences existed between the cohort of ABs and ACs.

Conclusion: Ki-67 IHC as a proliferation marker, particularly when assessed via automated methods, was helpful in distinguishing AC from AB cases. In contrast to other studies, surrogate IHC markers of embryonic stem cells, SOX2, OCT4 and GPC-3, were unreliable in distinguishing the two entities.

Introduction: Striated duct adenoma (SDA) is a rare benign salivary gland tumor with a recently described genetic signature. Recurrent oncogenic mutations affecting the IDH2 gene differentiate SDA from its primary differential diagnosis of canalicular adenoma. Here, we report a case of SDA affecting the parotid gland with IDH1/2 mutation-specific immunohistochemical positivity. Additionally, we provide a scoping review developed according to the Cochrane Methodology and reported following the Joana Briggs Institute (JBI) checklist to synthesize all previously published cases of SDA. The review protocol was registered on the Open Science Framework (OSF) platform ( https://osf.io/7mztg ). The searches were performed using Medline, Embase, Web of Science, and LILACS, with no date or language limit. Studies were evaluated for eligibility, extracted, and compiled in a narrative form. Seven studies with 20 patients with SDA, including ours, were analyzed. The tumors mainly affected the parotid gland (13/20) in patients with a mean age of 62 years and did not display sex predilection. Swelling was the leading clinical symptom. The mean follow-up duration was 26 months with no recurrence or metastasis after resection.

Conclusion: Awareness of the clinicopathological features and the use of IDH1/2 mutation-specific immunohistochemistry are pivotal for the consistent identification of SDA, and assessment for true biological potential will require increased follow-up and scrutiny.

Background: Metastatic intestinal adenocarcinoma involving the mandible is rare, posing diagnostic challenges because of its unusual presentation.

Case presentation: A 55-year-old male presented with a rapidly growing mass in the right mandible, accompanied by facial asymmetry and vestibular obliteration. Histopathological examinations revealed features consistent with adenocarcinoma. Immunohistochemical analysis supported the diagnosis of intestinal adenocarcinoma, with subsequent metastasis confirmed by PET scan findings.

Diagnosis: The lesion was conclusively diagnosed as intestinal adenocarcinoma metastasizing to the mandible.

Management: The patient pursued treatment at a government facility, leading to a loss of follow-up.

Purpose: The field cancerization concept indicates the presence of pre-cancerous changes in clinically normal tissue surrounding the tumor. In squamous cell carcinoma of the oral tongue (SCCOT) which is infrequently linked to human papillomavirus infection, we have previously reported that clinically normal tongue contralateral to tumor (NTCT) is molecularly abnormal. Here, combining our transcriptomic and genomic data, we aimed to investigate the contribution of molecular changes in NTCT to cancer development.

Methods: Microarray gene expression data of 14 healthy controls, 23 NTCT and 29 SCCOT samples were investigated to characterize transcriptional profiles in NTCT. Whole exome sequencing and RNA-sequencing data of paired NTCT and tumor samples from 15 SCCOT patients were used to study correlation between copy number variation and differential gene expression.

Results: Using supervised multivariate partial least squares discriminant analysis, a total of 61 mRNAs that distinguish NTCT from healthy tongue were selected. Functional enrichment analysis of the 22 upregulated genes showed increased "positive regulation of nitrogen compound metabolic process" in NTCT. All 12 genes involved in this process have roles in apoptosis (anti- and/or pro-apoptotic). Compared to healthy controls, Zinc Finger Protein 395 (ZNF395), a pro-apoptotic tumor suppressor located on chromosome 8p, was the only gene showing increased mRNA level in NTCT whereas decreased in SCCOT. Given the frequent loss of chromosome 8p in SCCOT, the impact of ZNF395 copy number variation on gene expression was further examined, revealing a positive correlation between copy number and mRNA level (correlation coefficient = 0.572, p < 0.001).

Conclusion: NTCT is susceptible to malignant transformation, where tissue homeostasis is maintained at least partly through regulation of apoptosis. Loss of the pro-apoptotic gene ZNF395 could thus initiate cancer development.

Purpose: DEK::AFF2 fusion-associated squamous cell carcinoma (DEK::AFF2 SCC), also reported in the literature as low-grade papillary sinonasal (Schneiderian) carcinoma (LGPSC), is a rare, primarily bland-appearing, but locally aggressive neoplasm. Morphologically, these tumors can closely resemble sinonasal papilloma (SP), especially on small or limited biopsy, often leading to misdiagnosis. DEK::AFF2 SCC is devoid of the underlying mutually exclusive EGFR or KRAS driver mutations of SP, suggesting it may represent a distinct unique entity.

Methods: In this study, we conducted a retrospective search of "unusual" SP reported either as atypical, dysplastic, or suspicious for malignant transformation at our institution in the last 13 years (2010-2023), to identify potential cases of DEK::AFF2 SCC.

Results: Of the 201 SP cases during this time period, 30 "unusual" SP cases were identified. On morphologic review of these 30 cases, 6 were worrisome for DEK::AFF2 SCC and were selected for AFF2 immunohistochemical stain (IHC), of which 3 cases were positive. All 3 AFF2 IHC positive cases were also positive for DEK::AFF2 fusion by fluorescence in situ hybridization (FISH), thereby, confirming IHC results.

Conclusions: This study highlights that AFF2 IHC can be an invaluable surrogate marker to FISH in identifying DEK::AFF2 SCC in challenging cases to avoid misdiagnosis. Detailed clinical and pathologic data were collected to gain a better understanding of this emerging challenging entity. A literature review was performed to enrich our knowledge of DEK::AFF2 SCC.

One pathologist reflects upon her own medical journey and shares how that perspective is carried forward in her practice and her life.

An 81-year-old male patient presented with a well-demarcated, unilocular radiolucent lesion in the right mandibular body, identified during a routine radiographic examination. Based on the clinical hypothesis of a residual cyst, enucleation with curettage was performed, and the specimen was submitted for histopathological analysis. Microscopically, the cystic lesion was predominantly lined by ameloblastomatous epithelium with numerous ghost cells and dentinoid. Additionally, other cystic cavities lined by stratified squamous epithelium with corrugated parakeratin were observed in the fibrous capsule. Based on these features, a final diagnosis of a calcifying odontogenic cyst with odontogenic keratocyst-like areas was established. No recurrence was observed over a 9-year follow-up period. The association of a calcifying odontogenic cyst with odontogenic keratocyst or odontogenic keratocyst-like areas is very rare. To date, this is the second case report in the literature presenting these findings.