Clinicopathologic findings in (anti-FcepsilonR1alpha) autoimmune-related chronic urticaria.

Background: One cause of chronic urticaria is autoreactivity which is diagnosed by detecting autoantibodies against the IgE receptor alpha subunit (anti-Fc R1alpha).

Objective: To compare the histopathologic features of chronic urticaria patients testing positive for anti-IgE receptor antibody (Ab) to those testing negative.

Methods: Totally, 438 patients with a clinical presentation of chronic urticaria (2011-2013) had anti-IgE receptor Ab tested and 37 of those patients had skin biopsy.

Cutaneous meningioma: a potential diagnostic pitfall in p63 positive cutaneous neoplasms.

Cutaneous meningiomas are divided into three groups. Type I lesions present at birth and are derived from ectopic arachnoid cells. Type II lesions usually present in adults and are derived from arachnoid cells surrounding nerve bundles.

Dermal hypersensitivity reaction: a PCR-confirmed pattern of herpetic dermatitis.

Background: Herpetic dermatitis due to herpes simplex virus (HSV) and varicella zoster virus (VZV) can present with similar clinical and histopathologic features. Further confounding matters, viral cytopathic changes are not always observed in biopsy specimens. Therefore, use of polymerase chain reaction (PCR) analysis can play an integral role in the definitive diagnosis of herpetic dermatitis and in the distinction of HSV-1/HSV-2 from VZV.

An audit of dermatopathology requisitions: hand written vs. electronic medical record data entry accuracy.

Background: At our institution, dermatopathology case requisitions are received in hand written form or via electronic medical record (EMR). Categories for requisition data entry include patient demographics, physician name and procedure site/date. Systematic data entry problems potentially cause considerable documentation error, propagate inaccurate patient information and potentially delay billing/revenue collection.

Expression of MiTF may be helpful in differentiating cellular neurothekeoma from plexiform fibrohistiocytic tumor (histiocytoid predominant) in a partial biopsy specimen.

Background: Overlapping histopathologic features of cellular neurothekeoma (CNT) and plexiform fibrohistiocytic tumor (PFHT), when both are predominantly composed of histiocytoid cells, make distinction between these entities challenging. Some have suggested that CNT and PFHT are related entities. No prior study has demonstrated a reliable immunohistochemical panel to differentiate these entities.

Increased diagnosis of thin superficial spreading melanomas: A 20-year study.

Background: Diagnostic practice by dermatopathologists evaluating pigmented lesions may have evolved over time.

Objectives: We sought to investigate diagnostic drift among a group of dermatopathologists asked to re-evaluate cases initially diagnosed 20 years ago.

Methods: Twenty nine cases of dysplastic nevi with severe atypia and 11 cases of thin radial growth-phase melanoma from 1988 through 1990 were retrieved from the pathology files of the Massachusetts General Hospital.

Injection site pseudosarcoma in piriformis syndrome.

Aims: Pseudosarcomatous reactive myofibroblastic proliferations have been described following surgery or trauma at a variety of anatomical sites. These types of reactions have not been previously described at injection sites. Here we evaluated prevalence, morphologic patterns and clinical resolution of such lesions.

Cellular neurothekeoma with fascicular growth features mimicking cellular dermatofibroma.

Background: Cellular neurothekeoma (CNT) is a benign cutaneous mesenchymal neoplasm. Most demonstrate a lobulated to micronodular architecture. Rarely, CNT demonstrates a predominantly fascicular growth pattern, without prominent sclerosis and thus can mimic cellular dermatofibroma (DF).

Cystic fibrosis transmembrane conductance regulator is helpful in the distinction of extra-mammary Paget's disease from squamous cell carcinoma in situ (Bowen's disease).

Cystic fibrosis transmembrane conductance regulator (CFTR) represents a cAMP-dependent channel found in normal apocrine glands. The classification and histogenesis of extra-mammary Paget's disease (EMPD) remains controversial, but it is generally accepted that primary EMPD exhibits apocrine differentiation. Therefore, we examined the utility of CFTR in the differential diagnosis of EMPD and squamous cell carcinoma in situ (SCCIS).

Sarcomatoid renal cell carcinoma presenting in the oropharynx.

Metastasis stemming from a distant malignancy is far less common than an oropharyngeal primary and represents only 1% of all oral neoplasms. The difficulty in diagnosing a metastasis in the oropharynx may be compounded if the lesion is poorly differentiated and bears little resemblance to the primary tumor. We present the case of synchronous metastatic renal cell carcinoma of the mandibular gingiva in a woman with sarcomatoid clear cell renal cell carcinoma.

Extra-acral cutaneous/soft tissue sclerosing perineurioma: an under-recognized entity in the differential of CD34-positive cutaneous neoplasms.

Background: Perineuriomas are an uncommon group of tumors composed of perineurial cells of peripheral nerve sheath lineage. Variants include soft tissue (extraneural), intraneural, sclerosing, reticular and plexiform forms. Sclerosing perineuriomas have been reported to occur almost exclusively on the hands of young men.

Utility of p63 in the differential diagnosis of atypical fibroxanthoma and spindle cell squamous cell carcinoma.

Atypical fibroxanthoma (AFX), spindle cell squamous cell carcinoma (SCSCC) and spindle cell melanoma are the primary entities in the differential diagnosis of a cytologically atypical spindle cell tumor arising on sun-damaged skin. AFX is generally regarded as a diagnosis of exclusion in this context: in the absence of S100 or keratin reactivity, a diagnosis of AFX is favored. However, keratin reactivity may be focal or even absent in SCSCC, and although numerous positive markers of AFX have been proposed, none has shown sufficient sensitivity and specificity for routine diagnostic use.

Malignant cutaneous glomus tumor presenting as a rapidly growing leg mass in a pregnant woman.

A 21-year-old pregnant woman presented with a rapidly growing >2 cm nodule on her right leg, involving dermis and subcutaneous tissue. Histologically, the tumor was composed of sheets and nests of neoplastic cells with variable cytomorphology, including typical round to ovoid glomus cells with clear cytoplasm and well-defined cell borders, small cells and spindle cells. Numerous medium to large vessels were present throughout the tumor.

Expression patterns of MITF during human cutaneous embryogenesis: evidence for bulge epithelial expression and persistence of dermal melanoblasts.

Unlabelled: The mechanisms whereby melanocytes populate the epidermis and developing hair follicles during embryogenesis are incompletely understood. Recent evidence implicates an intermediate mesenchymal stage in this evolutionary process in which HMB-45-positive melanocyte precursors ('melanoblasts') exist both in intradermal as well as intraepithelial and intrafollicular compartments. The melanocyte master transcriptional regulator, microphthalmia transcription factor (MITF), identifies mature melanocytes as well as melanocyte precursor stem cells that reside in the bulge region of the hair follicle.

Deep "benign" fibrous histiocytoma: clinicopathologic analysis of 69 cases of a rare tumor indicating occasional metastatic potential.

Benign fibrous histiocytoma (FH) is one of the most common mesenchymal neoplasms of the skin. Several histologic variants of cutaneous FH have been described, some of which also have distinct clinical features including a propensity for local recurrence. Deep benign FH is an uncommon and poorly recognized clinical subtype that arises in subcutaneous or deep soft tissue.

Osteofibrous dysplasia and adamantinoma in children and adolescents: a clinicopathologic reappraisal.

Osteofibrous dysplasia (OFD) and adamantinoma are rare and most commonly arise in the tibia of young individuals. Although OFD has typical histopathologic features, areas resembling OFD have often been noted at the periphery of otherwise classic adamantinomas, and some have suggested that OFD may be either a precursor to or a regressive phase of adamantinoma. The so-called OFD-like adamantinoma encompasses some features of both OFD and adamantinoma.

Immunosuppression-related fibroproliferative polyps: a substantial subset of acquired pediatric mucocutaneous polyps.

A distinct group of fibroproliferative polyps of the tongue arising in immunosuppressed children and often associated with chromosomal breakpoints at chromosomes 9p34 or 22q11 was recently described. Based on this finding, we reviewed fibroepithelial polyps arising in nonlingual sites in the pediatric population to investigate a possible relationship with immunosuppression. We identified 8 fibroepithelial polyps arising in 6 immunosuppressed patients (4 males and 2 females, median age 17 years) in a wide range of mucocutaneous sites.

Intravascular cytotoxic T-cell lymphoma: A case report and review of the literature.

Intravascular lymphoma (IVL) is a rare subtype of extranodal diffuse large B-cell lymphoma in the World Health Organization classification. Although the majority of cases are of B-cell lineage, cases of IVL with a T-cell phenotype and, rarely, histiocytic and natural killer (NK)-cell phenotypes have been reported. We report a case of T-cell IVL with a cytotoxic phenotype.

Atypical genital nevi. A clinicopathologic analysis of 56 cases.

Atypical genital nevi are rare melanocytic lesions that most commonly arise on the vulva of young women. They are currently regarded as nevi of special sites, in that despite histologically worrisome features, their clinical behavior is reportedly benign. However, only few studies with limited follow-up data are available.

Myoepithelial carcinoma of soft tissue in children: an aggressive neoplasm analyzed in a series of 29 cases.

Primary myoepithelial tumors of soft tissue are uncommon, and criteria for malignancy among these neoplasms have only recently been established. Of 51 myoepithelial carcinomas of soft tissue in the literature, 11 occurred in children, 7 of which were included in a previous series of myoepithelial tumors from our group. We have collected an additional 22 cases of myoepithelial carcinoma of soft tissue in the pediatric population, and we describe the detailed clinicopathologic features of all 29 cases herein.

Novel karyotypes in giant cell-rich lesions of bone.

Giant cell-rich lesions of bone, including giant cell tumor of bone, giant cell reparative granuloma (GCRG), and aneurysmal bone cyst (ABC), may have overlapping clinical, radiologic, and histopathologic features. In fact, GCRG and solid ABC are currently differentiated solely based on skeletal location. Prior cytogenetic studies have reported that telomeric associations are present in the majority of giant cell tumors of bone, whereas translocations involving 16q22 and/or 17p13 are characteristic of ABCs.

HMB-45 and Melan-A are useful in the differential diagnosis between granular cell tumor and malignant melanoma.

Granular cell tumors (GCTs), especially if atypical or malignant, may share cytomorphologic and architectural features with malignant melanoma, when the latter shows granular cell change. In many cases, these neoplasms can be differentiated from each other on histologic grounds, but distinction may sometimes be challenging. By immunohistochemistry, both tumors are strongly positive for S-100 protein and frequently express other nonspecific markers such as CD68, NSE, and NKIC3.

Non-bullous neutrophilic dermatosis: an uncommon dermatologic manifestation in patients with lupus erythematosus.

Background: Rare cases of a non-bullous neutrophilic dermatosis occurring in patients with lupus erythematosus (LE) have been reported, often as the presenting manifestation of the disease.

Methods: We reviewed hematoxylin and eosin-stained slides and obtained clinical information from four additional patients, two of whom had no prior history of LE.

Results: All patients were female, aged 16-59 (mean age 37).