Aldosterone deficiency after unilateral adrenalectomy for Conn's syndrome: a case report and literature review.

INTRODUCTION: Approximately 35% of cases of Conn's syndrome (primary aldosteronism) result from a solitary functioning adrenal adenoma, and these patients are best managed by adrenalectomy. Postoperative hypoaldosteronism after unilateral adrenalectomy is uncommon. CASE PRESENTATION: We present a case and literature review of hypoaldosteronism after unilateral adrenalectomy for Conn's syndrome, which demonstrates the insidious and sometimes delayed presentation. DISCUSSION: In this clinical case we summarize the previously published cases of post-adrenalectomy hypoaldosteronism based on a PUBMED and EBSCOhost search of all peer-reviewed publications (original articles and reviews) on this topic. A few cases of aldosterone insufficiency post-adrenalectomy for Conn's syndrome were identified. The etiological factors for prolonged selective suppression of aldosterone secretion after unilateral adrenalectomy remain unclear. CONCLUSION: It is important to be aware of the risk of postoperative hypoaldosteronism in this patient population. Close postoperative follow-up is necessary and strongly recommended, especially in patients with certain risk factors. Patients may need mineralocorticoid supplementation during this period.

Differential gene expression profiles of neurothekeomas and nerve sheath myxomas by microarray analysis.

Neurothekeomas and dermal nerve sheath myxomas have previously been considered related cutaneous neoplasms of peripheral nerve sheath origin based on light microscopic similarities. However, recent immunohistochemical and ultrastructural data indicate nerve sheath myxomas exhibit true nerve sheath differentiation, whereas no such compelling evidence exists for neurothekeomas. Although neurothekeomas lack a specific immunohistochemical profile, similar antigen expression and histopathologic patterns suggest neurothekeomas may be categorized as fibrohistiocytic tumors. To date, no known molecular studies have examined the histogenetic relationship of these tumors. We report the first microarray-based gene expression profile study of these entities on formalin-fixed paraffin-embedded tissues. Cases of dermal schwannomas, dermal nerve sheath myxomas, myxoid/mixed/cellular neurothekeomas, and cellular fibrous histiocytomas diagnosed in the past 3 years were identified in our database. Archival formalin-fixed paraffin-embedded tissue from 28 patients was selected for microarray analysis (seven schwannomas, five nerve sheath myxomas, nine myxoid/mixed/cellular neurothekeomas and seven cellular fibrous histiocytomas). Following tumor RNA isolation, amplification and labeling using commercially available kits, labeled targets were hybridized to the Affymetrix GeneChip Human Genome U133 Plus 2.0 Array (Santa Clara, CA, USA). Acquisition of array images and data analyses was performed using appropriate software. Hierarchical clustering and principal component analysis demonstrated discrete groups, which correlated with histopathologically identified diagnoses. Dermal nerve sheath myxomas demonstrate very similar molecular genetic signatures to dermal schwannomas, whereas neurothekeomas of all subtypes more closely resemble cellular fibrous histiocytomas. We are the first to report distinct gene expression profiles for nerve sheath myxomas and neurothekeomas, which further substantiates the argument that these are separate entities. Our molecular data confirms that dermal nerve sheath myxomas are of peripheral nerve sheath origin, and suggests that neurothekeomas may actually be a variant of fibrous histiocytomas.

Melanocytic matricoma with melanocytic atypia: report of a unique case and review of the literature.

Melanocytic matricoma is a rare cutaneous neoplasm of presumed anagen hair follicle origin with approximately 10 reported cases in the literature. Melanocytic matricomas are clinically and histopathologically distinct cutaneous nodular proliferations of matrical and supramatrical cells admixed with dendritic melanocytes, which typically occur in the sun-exposed areas of elderly patients. We report a new case with additional histopathologic features not previously described. An 82-year-old white man presented with an exophytic papule of the ear clinically suspicious for basal cell carcinoma. Histopathologic examination demonstrated a polypoid neoplasm consisting of an admixture of matrical and shadow cells with numerous interspersed dendritic and epithelioid melanocytes arranged singly and in large expansile nests. An unusual feature in this case included prominent melanocytic proliferation with associated nuclear atypia and increased mitotic activity. Although atypical and malignant melanocytic colonization has been reported in basal cell carcinomas and squamoproliferative lesions, to our knowledge, it has not been previously described in melanocytic matricomas. The biologic significance of atypical melanocytic proliferations within melanocytic matricomas is uncertain and requires further study of additional cases and long-term follow-up.

Benign vascular tumors and tumor-like proliferations.

Appropriate nomenclature of benign vascular tumors and tumor-like conditions is problematic due to overlapping histologic features, limited understanding of the pathogenesis, and controversy regarding classification. Benign vascular anomalies are categorized into malformations, neoplasms, reactive proliferations, or ectasias based on their clinical behavior, currently accepted etiologies, and histopathology. We address controversies in the classification of some entities and also discuss recent immunohistochemical developments that have raised questions regarding the origin of certain vascular tumors. This comprehensive review focuses on the clinical presentation, behavior, associated conditions, histopathological findings, and differential diagnoses of benign vascular tumors and tumor-like conditions.

Uterine epithelioid trophoblastic tumor in an African green monkey (Chlorocebus aethiops sabaeus).

A uterine mass was detected on physical exam in a multiparous African green monkey as an incidental finding, and the well-circumscribed mass was removed via hysterectomy. Histologically, the mass consisted of sheets, nests, and cords of uniform intermediate trophoblastic cells with eosinophilic or clear cytoplasm. These neoplastic cells aggregated around blood vessels, forming islands of viable tumor cells amid extensive areas of coagulative necrosis with calcification in a 'geographic' pattern of necrosis. Immunohistochemistry of the trophoblastic cells revealed strong and diffuse staining for pancytokeratin AE1/3 and p63, with weak and moderate staining for human placental lactogen and placental alkaline phosphatase, respectively. Immunohistochemical staining for smooth muscle actin, epithelial membrane antigen, and human chorionic gonadotropin was negative. Overall, the histologic and immunohistochemical features of this tumor were consistent with those of epithelioid trophoblastic tumor. This rare tumor type has not been reported previously to occur in African green monkeys.