Cell-free DNA methylation analysis as a marker of malignancy in pleural fluid.

Diagnosis of malignant pleural effusion (MPE) is made by cytological examination of pleural fluid or histological examination of pleural tissue from biopsy. Unfortunately, detection of malignancy using cytology has an overall sensitivity of 50%, and is dependent upon tumor load, volume of fluid assessed, and cytopathologist experience. The diagnostic yield of pleural fluid cytology is also compromised by low abundance of tumor cells or when morphology is obscured by inflammation or reactive mesothelial cells. A reliable molecular marker that may complement fluid cytology for the diagnosis of malignant pleural effusion is needed. The purpose of this study was to establish a molecular diagnostic approach based on pleural effusion cell-free DNA methylation analysis for the differential diagnosis of malignant pleural effusion and benign pleural effusion. This was a blind, prospective case-control biomarker study. We recruited 104 patients with pleural effusion for the study. We collected pleural fluid from patients with: MPE (n = 48), indeterminate pleural effusion in subjects with known malignancy or IPE (n = 28), and benign PE (n = 28), and performed the Sentinel-MPE liquid biopsy assay. The methylation level of Sentinel-MPE was markedly higher in the MPE samples compared to BPE control samples (p < 0.0001) and the same tendency was observed relative to IPE (p = 0.004). We also noted that the methylation signal was significantly higher in IPE relative to BPE (p < 0.001). We also assessed the diagnostic efficiency of the Sentinel-MPE test by performing receiver operating characteristic analysis (ROC). For the ROC analysis we combined the malignant and indeterminate pleural effusion groups (n = 76) and compared against the benign group (n = 28). The detection sensitivity and specificity of the Sentinel-MPE test was high (AUC = 0.912). The Sentinel-MPE appears to have better performance characteristics than cytology analysis. However, combining Sentinel-MPE with cytology analysis could be an even more effective approach for the diagnosis of MPE. The Sentinel-MPE test can discriminate between BPE and MPE. The Sentinel-MPE liquid biopsy test can detect aberrant DNA in several different tumor types. The Sentinel-MPE test can be a complementary tool to cytology in the diagnosis of MPE.

Cell-Free DNA Methylation Analysis as a Marker of Malignancy in Pleural Fluid.

Background: Diagnosis of malignant pleural effusion (MPE) is made by cytological examination of pleural fluid or histological examination of pleural tissue from biopsy. Unfortunately, detection of malignancy using cytology has an overall sensitivity of 50%, and is dependent upon tumor load, volume of fluid assessed, and cytopathologist experience. The diagnostic yield of pleural fluid cytology is also compromised by low abundance of tumor cells or when morphology is obscured by inflammation or reactive mesothelial cells. A reliable molecular marker that may complement fluid cytology malignant pleural effusion diagnosis is needed. The purpose of this study was to establish a molecular diagnostic approach based on pleural effusion cell-free DNA methylation analysis for the differential diagnosis of malignant pleural effusion and benign pleural effusion. Results: This was a blind, prospective case-control biomarker study. We recruited 104 patients with pleural effusion for the study. We collected pleural fluid from patients with: MPE (n = 48), PPE (n = 28), and benign PE (n = 28), and performed the Sentinel-MPE liquid biopsy assay. The methylation level of Sentinel-MPE was markedly higher in the MPE samples compared to BPE control samples (p < 0.0001) and the same tendency was observed relative to PPE (p = 0.004). We also noted that the methylation signal was significantly higher in PPE relative to BPE (p < 0.001). We also assessed the diagnostic efficiency of the Sentinel-MPE test by performing receiver operating characteristic analysis (ROC). For the ROC analysis we combined the malignant and paramalignant groups (n = 76) and compared against the benign group (n = 28). The detection sensitivity and specificity of the Sentinel-MPE test was high (AUC = 0.912). The Sentinel-MPE appears to have better performance characteristics than cytology analysis. However, combining Sentinel-MPE with cytology analysis could be an even more effective approach for the diagnosis of MPE. Conclusions: The Sentinel-MPE test can discriminate between BPE and MPE. The Sentinel-MPE liquid biopsy test can detect aberrant DNA in several different tumor types. The Sentinel-MPE test can be a complementary tool to cytology in the diagnosis of MPE.

Pediatric cellular neurothekeoma: Seven cases and systematic review of the literature.

BACKGROUND/OBJECTIVES: Neurothekeoma is a rare, benign, cutaneous neoplasm consisting of Schwann cells and perineural cells in myxoid stroma. Cellular neurothekeoma (CNT) was previously thought to represent a morphologic variant of neurothekeoma, but recent studies have shown that CNTs are unrelated to neurothekeomas and are more likely of histiocytic lineage. METHODS: Herein, we describe seven cases of CNT in pediatric patients. A comprehensive search of PubMed was performed, and 71 cases of cellular neurothekeoma in pediatric patients were reviewed. RESULTS: The clinical differential diagnosis for these lesions included Spitz nevi, keloid, juvenile xanthogranuloma, cutaneous lymphoid hyperplasia, and lymphomatoid papulosis. All cases were treated by excision or excisional biopsy. Histopathologically, all demonstrated multilobular, primarily intradermal neoplasms composed of plump spindled or epithelioid mononuclear cells with abundant eosinophilic pale-staining cytoplasm. Immunophenotypic findings included CD68 and NKI/C3 positivity, and negative staining with cytokeratin, S-100, Melan-A, and SOX-10. CONCLUSION: Cellular neurothekeoma is distinguished from conventional neurothekeoma by increased cellularity, a lack of myxoid stroma, and a lack of neural expression with immunohistochemical stains. These uncommon neoplasms should be included in the differential diagnosis of dermal nodules in children. Accurate diagnosis of these lesions is essential, as they can be mistaken for malignancy leading to unnecessary treatment.

Gamma-interferon-inducible lysosomal thiol reductase is upregulated in human melanoma.

T-cell-mediated immunity has the ability to produce durable antimelanoma responses, resulting in improved survival of patients with advanced melanoma. Antigen presentation is a key determinant of T-cell responses. Gamma-interferon-inducible lysosomal thiol reductase (GILT) is critical for MHC class II-restricted presentation of multiple melanoma antigens to CD4+ T cells. However, GILT expression in melanoma has not been defined. We evaluated GILT and MHC class II expression in human primary and metastatic melanomas and nevi using immunohistochemical analysis. GILT staining in melanocytes was observed in 70% of primary and 58% of metastatic melanomas versus 0% of nevi. When present, the GILT staining intensity in melanocytes was typically faint. Both GILT and MHC class II expression were increased in melanocytes of primary and metastatic melanomas compared with nevi. GILT staining in antigen-presenting cells (APCs) was detected in 100% of primary and metastatic melanomas versus 31% of nevi, and it was typically intense. GILT expression was increased in APCs of primary and metastatic melanomas compared with nevi, whereas MHC class II had equivalent high expression in APCs of all melanocytic lesions. GILT staining in keratinocytes was detected in 67% of primary melanomas versus 14% of nevi and 6% of metastatic melanomas. GILT, but not MHC class II, expression was increased in keratinocytes of primary melanomas compared with nevi and metastases. GILT expression is anticipated to result in improved presentation of melanoma antigens and more effective antimelanoma T-cell responses. GILT expression may be a biomarker of immune recognition of melanoma.

A case of generalized eruptive histiocytosis in a 23-year-old man.

Generalized eruptive histiocytosis (GEH) is an exceedingly rare type of Factor XIIIA-positive histiocytopathy, characterized by symmetric distribution of red-brown papules on the trunk, proximal extremities, and face. It is diagnosed by the integration of the clinical features, light microscopic findings, and phenotypic profile. Herein, we report an unusual presentation of GEH in a 23-year-old man, who had a striking papular and erythrodermic component to his lesions.

Eccrine squamous metaplasia and periadnexal granulomas: new cutaneous histopathologic findings in cardiofaciocutaneous syndrome.

Cardiofaciocutaneous syndrome is a rare genetic disorder characterized by dysmorphic facial features and neurologic, cardiac, ophthalmologic, and dermatologic findings. Previously reported skin and hair findings in cardiofaciocutaneous syndrome include sparse, slow-growing curly hair, atopic dermatitis, ichthyosis, follicular hyperkeratosis, and keratosis pilaris. We report the case of a 4-year-old boy who has cardiofaciocutaneous syndrome with previously unreported histopathologic findings of eccrine squamous metaplasia and periadnexal granuloma.

Gloves and socks syndrome: early and late histopathologic features.

BACKGROUND: Gloves and socks syndrome (GSS) is a recently described exanthem, most commonly caused by parvovirus B19. OBJECTIVE: Our purpose was to describe both early and late histopathologic features of GSS. METHODS: We performed histopathologic examination of biopsy specimens from a case of GSS and reviewed all the English-language literature reports of GSS to compare the reported histologic descriptions. RESULTS: A total of 46 cases of GSS have been reported in the English-language literature. In 18 of those, the pathologic features were described. The histologic features of the current case evolved from a nonspecific superficial perivascular lymphocytic infiltrate to a vacuolar interface dermatitis with necrotic keratinocytes, erythrocyte extravasation, and a superficial perivascular and interstitial lymphocytic infiltrate. CONCLUSION: Early lesions of GSS show nonspecific features common to viral exanthems. The late features, of a fully evolved exanthem, demonstrate a vacuolar interface dermatitis with necrotic keratinocytes, a superficial perivascular and interstitial infiltrate, and dermal hemorrhage. These late pathologic features, together with the clinical appearance of GSS, may help distinguish it from other entities.

Spiradenocarcinoma of the scalp.

Spiradenocarcinoma is an exceedingly rare malignant neoplasm with ductal differentiation. Many consider it to be an eccrine neoplasm, and others favor apocrine differentiation. In nearly all cases, spiradenocarcinoma is associated with a benign spiradenoma, with most lesions appearing on the trunk and extremities. We describe a patient who presented with a long-standing and previously asymptomatic scalp nodule that became tender and enlarged. After diagnosis of spiradenocarcinoma, the patient was referred for lymphoscintigraphy, sentinal lymph node biopsy, and Mohs micrographic surgery.