Adjunct therapeutic plasma exchange for anti-N-methyl-D-aspartate receptor antibody encephalitis: a case report and review of literature.

Encephalitis associated with autoantibodies directed against the N-methyl-D-aspartate receptor (NMDAR) is usually a paraneoplastic syndrome that presents in young females with ovarian teratomas. We report a case of a previously healthy 14-year-old girl with sudden-onset paranoia, hallucinations, hyperactivity, increased speech, decreased sleep, seizures, and violent behavior deteriorating to catatonia. Her cerebrospinal fluid tested positive for anti-NMDAR antibodies. She was treated with five sessions of therapeutic plasma exchange (TPE) after having failed therapy with antibiotics, intravenous steroids, intravenous immunoglobulin (IVIG), one dose of rituximab, and seven sessions of electroconvulsive therapy (ECT). The American Society for Apheresis assigns a Category III (Grade 2C) recommendation for TPE in paraneoplastic neurologic syndromes; however, apheresis specifically for anti-NMDAR encephalitis has not been well studied. Literature review revealed two case reports describing outstanding improvement in patients with anti-NMDAR encephalitis following TPE. We report no improvement in our patient's symptoms after plasma exchange and discuss possible reasons for why it failed along with review of the literature.

Vascular tumors of the mediastinum.

Vascular tumors represent only a sliver of all tumors affecting the mediastinum, but they pose diagnostic challenges due to significant overlap among entities, ever-evolving classification schemes, and the exquisite rarity of some of the entities not only in the mediastinum but in pathology practice as a whole. Most of the vascular tumors are better known to the practice of soft tissue pathology, from which some of the knowledge of clinical behavior can be extrapolated. For example, the stratification of epithelioid hemangioendothelioma (EHE) into two biologically separate categories has effectively translated from the somatic soft tissues to the thorax. For other entities, the effective validation of soft tissue parameters is hindered by the small numbers of reported mediastinal cases. Many of the treatment modalities have also transferred over, with the key differences resting on the difficulty in achieving complete surgical resection for mediastinal tumors as opposed to those in the somatic soft tissues. Accordingly, systemic drug therapies have emerged as attractive options for some of the mediastinal vascular tumors, such as kaposiform hemangioendothelioma (KHE) and Kaposi sarcoma (KS). The categories presented herein mirror the classification scheme set forth by the 5th Edition WHO Classification of Soft Tissue and Bone Tumors. This review focuses on the biologically aggressive vascular neoplasms while limiting discussion of the benign entities to relevant comparisons in the differential diagnoses. While distinguishing among the benign entities has academic importance, in practice, the stakes are far higher for diagnosing the biologically aggressive tumors given their marked heterogeneity in clinical outcomes. Practical advice for problem areas in pathology will be reviewed alongside tumor pathobiology, including the latest in molecular diagnostics.

Extraskeletal Ewing Sarcoma of the Jejunum: A Case Report.

INTRODUCTION: Ewing sarcoma most commonly arises in bones but rarely presents in extraskeletal locations. We report one such case arising from the jejunum. CASE PRESENTATION: A 67-year-old woman presented with acute-onset, right lower quadrant pain. Computed tomography results showed a large mass within the midjejunum with pneumoperitoneum. Surgical excision was performed, and an extraskeletal Ewing sarcoma of the jejunum was suspected histologically. The diagnosis was confirmed with fluorescence in situ hybridization studies. CONCLUSION: This case emphasizes the importance of recognizing this rare presentation in the small intestine to broaden the differential diagnosis of adult intraabdominal tumors.

Prognostic role of tumoral PDL1 expression and peritumoral FoxP3+ lymphocytes in vulvar melanomas.

The prognostic role of PDL1 expression, CD8+ and FoxP3+ lymphocytes in vulvar melanomas has not been studied. We correlated PDL1 expression and CD8+ and FoxP3+ immune infiltrates with clinicopathologic variables and patient outcomes in a series of 75 vulvar melanomas. Tumoral PDL1 expression (>5%) was seen in 23% of cases. By Fisher exact test, PDL1 expression and peritumoral FoxP3+ lymphocytes significantly correlated with less disease-specific death. By linear regression analysis, correlations between tumoral PDL1 expression with the density of tumoral CD8+ and peritumoral CD8+ lymphocytes, tumoral FoxP3+ with tumoral CD8+ lymphocytes, and peritumoral FoxP3+ with peritumoral CD8+ lymphocytes were observed. By univariate analyses, tumor thickness >4 mm predicted poorer progression-free survival, melanoma-specific survival, and overall survival. PDL1 expression >5% and peritumoral CD8+, peritumoral FoxP3+, and tumoral FoxP3+ lymphocytes correlated with better overall survival. By multivariate analyses, high peritumoral FoxP3+ lymphocytes independently predicted better melanoma-specific survival (P = .023), and tumor thickness independently predicted poorer progression-free survival (P = .05) and overall survival (P = .039). In conclusion, our study shows that, independent from tumor thickness, an increased density of peritumoral FoxP3+ lymphocytes may positively impact survival in a subset of vulvar melanomas. Tumoral PDL1 expression correlated with tumoral as well as peritumoral CD8+ and FoxP3+ lymphocytes, supportive of an adaptive immune response. Although the frequency of PDL1 expression is low in vulvar melanoma, its expression may identify a subset of vulvar melanoma that might respond to immunotherapy.

Acral manifestations of soft tissue tumors.

This group of biologically diverse entities is united by topographic localization to the hands and feet. Categorizing tumors by body site narrows the differential into a short list of possibilities that can facilitate accurate and rapid diagnosis. The goal of this review is to provide a practical approach to soft tissue tumors of acral locations for clinicians, pathologists, and researchers alike. What ensues in the following text is that tight coupling of the clinical picture and histopathologic findings should produce the correct diagnosis, or at least an abbreviated differential. The salient clinicopathologic, immunohistochemical, and molecular features are presented alongside current treatment recommendations for each entity.

Disseminated Malignant Rhabdoid Tumor of the Head and Neck.

Disseminated extrarenal malignant rhabdoid tumors of the head and neck are very rare, but aggressive tumors. Although the features on radiological imaging may be nonspecific, the imaging is useful for assessing the extent of tumor involvement. Key pathologic features are those of a cellular "blue cell tumor" with variable rhabdoid appearance. These cells express a combination of markers usually viewed as characteristic of diverse lines of differentiation, including EMA, cytokeratins, smooth muscle markers, and GFAP, and occasionally synaptophysin. At a molecular level, the entity is defined by mutations or alterations in the SMARB1/INI1 gene resulting in loss of INI1 expression. Diagnostic features include rhabdoid cells, expression of keratin with absence of desmin, S100 protein and CD34, and loss of INI1 expression. These features are exemplified in this sine qua non radiology-pathology correlation article.

MYC Amplification in Angiosarcoma Arising from an Arteriovenous Graft Site.

Angiosarcoma arising in association with an arteriovenous graft (AVG) or fistula is a unique clinicopathologic scenario that appears to be gaining recognition in the literature. Among reported cases, none has described high-level MYC gene amplification, a genetic aberration that is increasingly unifying the various clinicopathologic subdivisions of angiosarcoma. We therefore report the MYC gene status in a case of angiosarcoma arising at an AVG site.

CD34 and α smooth muscle actin distinguish verrucous hyperplasia from verrucous carcinoma.

OBJECTIVE: This study evaluated the use of stromal biomarkers CD34 and α smooth muscle actin (α-SMA) to distinguish verrucous carcinoma (VC) from verrucous hyperplasia (VH). STUDY DESIGN: Thirteen VH, 15 VC, 20 squamous cell carcinoma (SCC), and 16 of uninvolved adjacent stroma specimens were analyzed for α-SMA and CD34 expression by immunohistochemistry. RESULTS: Stromal α-SMA positivity was observed in 100% (20 of 20) of the SCC and in 93% (14 of 15) of the VC, whereas none of the VH (0 of 13) or adjacent uninvolved stroma (0 of 16) demonstrated α-SMA reactivity. Stromal CD34 positivity was observed in 100% (13 of 13) of VH and adjacent stroma (16 of 16), while 20% (3 of 15) of VC and 11% (2 of 18) of SCC stroma expressed CD34. The SCC and VC groups differed significantly from the VH and uninvolved stroma groups for both α-SMA and CD34 expression (P < .0001). CONCLUSIONS: Stromal CD34 and α-SMA protein expression patterns may aid in distinguishing between VC and VH in challenging cases.