Erdheim-Chester disease: a histiocytic disorder more than skin deep.

Erdheim-Chester disease is a rare potentially malignant systemic non-Langerhans cell histiocytosis. Although classically described in the pulmonary system and long bones, cutaneous involvement has been chronicled in 2 previous case reports. Herein, we describe a single systemic case afflicting an elderly man with synchronous multifocal cutaneous disease. The previous literature and pertinent differential diagnosis will be discussed.

Primary cutaneous osteoblastic osteosarcoma: a case report and review of the current literature.

Osteosarcoma is a malignant bone-forming tumour that typically arises within the metaphysis of long bones. Extraskeletal osteosarcoma is a rare variant that usually arises in the deep soft tissues, especially in the legs. We report a 65-year-old white man with an ulcerated, nodular lesion of the forearm. Based on the histological features and immunohistochemical profile of the tumour, a diagnosis of osteoblastic osteosarcoma was made. Osteosarcoma arising in the skin is a rare condition that has seldom been reported in the English literature.

Merkel cell carcinoma in a renal transplant patient: increased incidence?

The identification of malignancies associated with transplantation has led to enhanced vigilance and care in these patients, as well as insight into the pathogenesis of select malignancies. We report a case of Merkel cell carcinoma, an uncommon cutaneous malignancy of neuroendocrine origin, diagnosed in a 65-year-old Caucasian man 6 years after renal transplantation. While it is well known that transplant patients are at increased risk for squamous cell carcinomas of the skin, other types may also have an increased frequency. We suggest that Merkel cell carcinoma could have an increased incidence in the transplant population.

Establishment and characterization of a new mantle cell lymphoma cell line, Mino.

Mantle cell lymphoma (MCL) is a distinct type of B-cell non-Hodgkin's lymphoma characterized by cyclin D1 overexpression and the cytogenetic abnormality, the t(11;14)(q13;q32). MCL cell lines have been difficult to establish and in vitro studies of these neoplasms are scarce. We describe the establishment and characteristics of a new MCL cell line, Mino. The cells are large, growing singly and in small clumps in vitro. By flow cytometry, the immunophenotype was compatible with MCL (i.e. CD5+CD20+CD23-FMC7+). Conventional cytogenetics showed hyperdiploidy with multiple complex karyotypic abnormalities, but no evidence of the t(11;14), proven to be present only by fluorescence in situ hybridization and polymerase chain reaction (PCR) methods. Western blots showed expression of cyclin D1 but no detectable cyclin D2 and cyclin D3; the retinoblastoma protein was predominantly phosphorylated. There was expression of tumor suppressor gene products including p53, p16(INK4a), and p21(WAF1). Sequencing of the TP53 gene revealed a mutation (codon 147(valine-->glycine)) in exon 5. Epstein Barr virus was absent. In summary, Mino is a new MCL cell line that may be useful to study the pathogenesis of MCL.

Myofibroblastoma of the breast revisited: an etiologic association with androgens?

Myofibroblastoma of the breast is an uncommon benign stromal tumor encountered predominantly among elderly men. Histologically, myofibroblastoma is a well-circumscribed tumor comprised of bipolar spindle cells arranged in short fascicles traversed by collagen bundles. Based on previous histological, immunohistochemical, and ultrastructural observations, this tumor is thought to be derived from myofibroblasts. The pathogenesis of myofibroblastoma is unknown. Given the demographics of this lesion, the established trophic effect of steroid hormones, and the potential diagnostic utility of hormone receptor analysis in differentiating spindle cell tumors, we immunohistochemically tested for estrogen and androgen receptors in a host of spindle cell lesions including myofibroblastoma of the breast. Five cases reported herein of histological confirmed myofibroblastoma obtained from male and female breasts each showed strong nuclear antibody staining for the androgen receptor, not seen in four cases of leiomyosarcoma, three cases of fibromatosis, three cases of dermatofibrosarcoma protuberans, and two cases of monophasic synovial sarcoma. We postulate that the androgen receptor or its ligands may be pathologically related to the development of myofibroblastoma of the breast and diagnostically useful in differentiating it from other spindle cell lesions.

Comparison of BACTEC 12B vs solid media for the recovery of Mycobacterium avium complex from blood cultures in AIDS patients.

We compared liquid (BACTEC 12B) and solid culture media for the diagnosis of Mycobacterium avian complex (MAC) bacteremia among 258 AIDS patients with a positive blood culture. Neither culture media alone had adequate sensitivity; BACTEC 12B detected growth earlier. Use of both liquid and solid media may improve the yield of mycobacterial blood culture.

Cocaine increases beta-myosin heavy-chain protein expression in cardiac myocytes.

BACKGROUND: As many as 47% of chronic cocaine users develop cardiac ventricular hypertrophy. The presence and degree of cocaine-induced ventricular hypertrophy is not correlated with the use of other substances of abuse such as alcohol or cigarettes. Moreover, this hypertrophy occurs in individuals without sustained increases in arterial blood pressure or heart rate, or increases in the plasma concentration of renin, aldosterone, norepinephrine, or cortisol. Therefore, we investigated whether cocaine, in concentrations commonly found in cocaine users, has any direct effects on the protein content in cardiac ventricular myocytes. We compared the effects of cocaine with norepinephrine, which increases the total protein content, especially beta-myosin heavy-chain contractile protein (beta-MHC), in cardiac ventricular myocytes. METHODS: Experiments were performed on 30-day-old rat ventricular myocytes suspended in culture media and cultured in flasks. In 12 suspension-culture experiments, cocaine or norepinephrine, in doses of 0 (control) or 10(-6) mol/L was added to each culture and the cells were harvested on day 5. In 16 flask-culture experiments, cocaine or norepinephrine was added to each culture on day 7 in doses of 0 (control-vehicle), 10(-7), or 10(-6) mol/L and the cells were harvested on day 10. The total protein content and the myosin protein expression of the myocytes in each culture were determined. Juvenile and adult rat cardiac myosin protein is predominately alpha-myosin heavy-chain protein (alpha-MHC), whereas beta-MHC occurs primarily in fetal rat hearts. RESULTS: In the suspension-culture experiments, cocaine, 10(-6) mol/L, increased the cardiomyocyte total protein concentration by 29% +/- 2% (P <.001) and the beta-MHC expression by 81% +/- 10% (P <.01) in comparison with the control myocytes. Cocaine slightly decreased cardiomyocyte alpha-MHC. Norepinephrine increased the total protein concentration by 21% +/- 3% (P <.001) and the beta-MHC expression by 59% +/- 10% (P <.01), but did not increase alpha-MHC expression. In the flask-culture experiments, cocaine, 10(-6) mol/L, maximally increased the total protein concentration by 28% (P <.001), the protein/cell ratio by 57% +/- 10% (P <.01), and the beta-MHC expression by 85% +/- 8% (P <.01). Cocaine slightly decreased alpha-MHC. Norepinephrine, 10(-6) mol/L, maximally increased the total protein concentration by 35%, the protein/cell ratio by 63% +/- 9% (P <.01), and the expression of beta-MHC by 78% +/- 11% (P <. 01). Norepinephrine did not increase alpha-MHC expression. In 18 separate flask-culture experiments, cocaine, 10(-6) mol/L, was added to the cardiomyocyte cultures after the addition of phentolamine (n = 9), in concentrations of 10(-7) to 10(-5) mol/L, or metoprolol (n = 9), in concentrations of 10(-7) to 10(-5) mol/L. Neither phentolamine nor metoprolol inhibited the cocaine-induced increase in cardiomyocyte total protein content or the expression of beta-MHC. CONCLUSION: Cocaine, similar to norepinephrine, significantly increases the total protein content and the expression of beta-MHC in cardiac ventricular myocytes. In this manner, cocaine may cause cardiac ventricular hypertrophy. This process is not inhibited by alpha- or beta-adrenergic receptor blockade.

Assessing coral stress responses using molecular biomarkers of gene transcription.

We present a method for detecting rapid changes in coral gene expression at the messenger ribonucleic acid (mRNA) level. The staghorn coral Acropora cervicornis was exposed to 1 and 10 microg/L permethrin and 25 and 50 microg/L copper for 4 h. Using differential display polymerase chain reaction (PCR), mRNA associated with each toxicant exposure were reverse transcribed into complementary DNA (cDNA) fragments that were subsequently amplified and isolated. Six differentially expressed cDNA fragments were further developed into molecular probes that were used in Northern dot blots to determine the change in transcription levels of target transcripts. Changes in mRNA abundance were quantified by densitometry of chemiluminescence of digoxigenin-labeled probes hybridizing to target mRNA transcripts. The six gene probes showed varying degrees of sensitivity to the toxicants as well as specificity between toxicants. These probes were hybridized in Southern blots to genomic DNA from A. formosa sperm, which lacks zooxanthellae, to demonstrate that the genes coding for the mRNA transcripts produced are found within the coral genome. The gene probes developed in this study provide coral biologists with a new tool for coral assessment. Gene probes are sensitive, toxicant-specific biomarkers of coral stress responses with which gene sequence information can be obtained, providing a mechanism for identifying the stressor altering the gene expression.

Eruptive vellus hair cysts and neurologic abnormalities: two related conditions?

A fifteen-year-old white boy with a history of seizure disorder, borderline cognitive function, academic difficulty, and explosive temper outbursts was evaluated for asymptomatic flesh-colored papules appearing on his chest, abdomen, and axillae. Examination of a biopsy specimen showed eruptive vellus hair cysts; results of genetic, endocrinologic, and neuropsychiatric evaluation revealed abnormalities suggestive of a previously undescribed neurocutaneous syndrome.

Elastofibroma of the foot: uncommon presentation: a case report and review of the literature.

We report the clinical, microscopic and ultrastructural features of an elastofibroma arising in the foot. The lesion typically occurs in the elderly, and in 85% of cases arises from the connective tissue of the posterior chest wall. The histopathologic features of this lesion are distinctive, and are characterized by a haphazard array of eosinophilic collagen and elastic fibers, associated with fibroblasts and aggregates of mature fat cells. There are only two reported cases in the literature arising in the foot.

Sub-lethal coral stress: detecting molecular responses of coral populations to environmental conditions over space and time.

In order for sessile organisms to survive environmental fluctuations and exposures to pollutants, molecular mechanisms (i.e. stress responses) are elicited. Previously, detrimental effects of natural and anthropogenic stressors on coral health could not be ascertained until significant physiological responses resulted in visible signs of stress (e.g. tissue necrosis, bleaching). In this study, a focused anthozoan holobiont microarray was used to detect early and sub-lethal effects of spatial and temporal environmental changes on gene expression patterns in the scleractinian coral, Montastraea cavernosa, on south Florida reefs. Although all colonies appeared healthy (i.e. no visible tissue necrosis or bleaching), corals were differentially physiologically compensating for exposure to stressors that varied over time. Corals near the Port of Miami inlet experienced significant changes in expression of stress responsive and symbiont (zooxanthella)-specific genes after periods of heavy precipitation. In contrast, coral populations did not demonstrate stress responses during periods of increased water temperature (up to 29°C). Specific acute and long-term localized responses to other stressors were also evident. A correlation between stress response genes and symbiont-specific genes was also observed, possibly indicating early processes involved in the maintenance or disruption of the coral-zooxanthella symbiosis. This is the first study to reveal spatially- and temporally-related variation in gene expression in response to different stressors of in situ coral populations, and demonstrates that microarray technology can be used to detect specific sub-lethal physiological responses to specific environmental conditions that are not visually detectable.

A surreptitious sinister sarcoma.

Angiosarcoma is an exceedingly rare endothelial-derived sarcoma that, when seen, usually presents as an expanding bruise-like patch or violaceous papule/nodule on the head of an elderly patient. Herein, we present the histologic features of an unusual case that defied initial diagnosis.

Dermal atypical lipomatous tumor/well-differentiated liposarcoma obfuscated by epidermal inclusion cyst: a wolf in sheep's clothing?

Epidermal inclusion cysts are an exceedingly common entity seldom seen in association with a malignant tumor. Herein, we report a unique case of an epithelial inclusion cyst seen in association with an atypical lipomatous tumor/well-differentiated liposarcoma. The epidermal inclusion cyst was delimited to the dermis and circumferentially enveloped by an atypical adipocyte tumor containing myxoid foci and comprised of lipoblasts. This case underscores the importance of scrutinizing the entirety of cysts and other ostensibly trivial dermal entities to avoid the pitfall of misdiagnosing a potentially serious tumor.

Benign lichenoid keratosis: a clinical and pathologic reappraisal of 1040 cases.

Benign lichenoid keratosis, otherwise known as lichen planus-like keratosis, is a common, cutaneous entity that is often confused with cutaneous malignancy. Few studies have examined the multiple clinical and pathologic guises of this entity, particularly within the context of clinical pathologic correlation or magnitude of this study. We examined the epidemiologic, clinical, and pathologic attributes of 1040 consecutive cases of benign lichenoid keratosis referred for pathologic examination at a busy laboratory over an entire year. Clinical parameters assessed included the age, anatomic location, gender, and multiplicity of the lesions. Pathologic attributes were assessed yielding discernment of five different subtypes that included a classic type, bullous type, atypical type with cytologically atypical lymphocytes, an early or interface type, and a late regressed or atrophic type. The results yielded an average age at presentation of 59.5 years with an age range of 36 to 87 years. The gender frequency was 76% female, 24% male. The trunk was the most common location (76%), followed by the extremities (33%) and head and neck (7%); 8% of patients presented with two lesions and less than 1% with three lesions prompting consideration of lichen planus. The classic, atypical, and bullous forms of the disease clinically presented with erythematous papule/plaque(s). The early or interface type showed erythematous to hyperpigmented brown macules and the regressed or atrophic type presented as violaceous papules or irregularly distributed macular pigmentation; 81% of the lesions showed the classic histology consisting of epidermal acanthosis with a band-like lichenoid lymphocytic infiltrate. Variable numbers of plasma cells, eosinophils, and neutrophils were identified as well as epidermal parakeratosis distinguishing these lesions from typical lichen planus. The bullous variant showed intraepidermal or subepidermal bullous cavities with a dense associated lymphocytic infiltrate and increased numbers of necrotic basilar layer keratinocytes. The atypical variant showed features of the classic type with scattered enlarged CD-3, CD-30 (+) lymphocytes possessing hyperchromatic, irregular nuclei. The early interface type showed single lymphocytes aligned along the dermoepidermal junction without epidermal acanthosis and adjacent lentigo. The regressed or atrophic variant showed epidermal atrophy with papillary dermal scarring, patchy lymphocytic infiltrates and melanin incontinence. The clinicopathologic spectrum of benign lichenoid keratosis is broad and encompasses several unrelated entities. An awareness of its expanded presentation is essential to avoid misdiagnosis and may serve as an important forerunner of pathogenic discernment.

Ectopic prostatic tissue of the anal canal.

A unique case is reported of ectopic prostatic tissue present within the anal submucosa from a routine ischial decubitus resection specimen. Although ectopic prostatic tissue has been reported at loci adjoining the prostate, most notably within the urethra, this case is noteworthy by merit of its disparate location.

Disseminated acanthamoebiasis presenting as lobular panniculitis with necrotizing vasculitis in a patient with AIDS.

BACKGROUND: Disseminated acanthamoebiasis is a rare entity, almost exclusively occurring in the immunocompromised host. METHODS: We report an unusual case of a 35-year-old female with recurrent sinusitis and multiple skin nodules demonstrating a necrotizing panniculitis, shown to be due to disseminated acanthamoebiasis. RESULTS: Histologic sections showed a neutrophilic lobular panniculitis with 20- to 30-microm trophozoites consistent with Acanthamoeba species. CONCLUSIONS: A review the literature shows that the histopathological presentation of acanthamoebiasis often eludes initial diagnostic attempts and that central nervous system (CNS) involvement is frequent and ultimately fatal. When amoebiasis is suspected, knowledge of the trophozoite and cyst forms may be helpful in distinguishing Acanthamoeba species from Entamoeba histolytica.

Cutaneous indeterminate cell histiocytosis: a new spindle cell variant resembling dendritic cell sarcoma.

BACKGROUND: Cutaneous indeterminate cell histiocytosis is a rare neoplastic disorder. Its varied histological presentation and rarity have limited efforts to determine its pathogenic relationship with other histiocytic lesions and possibly, its recognition. METHODS: We report on an unusual histologic pattern of indeterminate cell histiocytosis that resembled follicular dendritic sarcoma. A battery of immunohistochemical stains and electron microscopy were performed to elucidate the phenotype of the "histiocytic" cells. Based on a review of the literature, reported cases of indeterminate cell histiocytosis are presented and the diagnostic differential of spindle-cell lesions is discussed. RESULTS: Spindling histiocytes were positive for S-100 and CD1a. The monocytic/macrophage marker, CD68, and the dendritic cell marker, CD21, were negative. Electron microscopy failed to reveal Birbeck granules. CONCLUSIONS: Relatively few reports of indeterminate cell histiocytosis exist, some of which include discussion of potential overlaps with the non-X histiocytoses. Although the presence of prominent spindling in our case expanded the differential to include non-histiocytic disorders, the identified histiocytes unequivocally fulfilled the criteria of S-100 and CD1a positivity without demonstrable Birbeck granules.