Rare Case Report of Pilomatrical Carcinosarcoma in a Pediatric Patient.

We present a case report of the exceptionally rare pilomatrical carcinosarcoma in an even rarer pediatric age group, a 9-year-old female patient. The tumor showed biphasic pilomatrical carcinoma and malignant sarcomatous transformation. To date, the patient is healing well without signs of recurrence. Although limited clinical follow-up is available due to the recent diagnosis, this case may provide a rare look at the clinical outcome of this very rare tumor.

Secretory Carcinoma of the Skin Harboring ETV6 Gene Fusions: A Cutaneous Analogue to Secretory Carcinomas of the Breast and Salivary Glands.

Mammary analogue secretory carcinoma is a low-grade salivary gland carcinoma that exhibits analogous features to secretory carcinoma of the breast including the presence of a t(12;15) translocation resulting in the ETV6-NTRK3 gene fusion. Rare cases of purported secretory carcinoma of the skin adnexa have been reported, but their relationship to true secretory carcinoma of the breast and salivary glands is unclear, as they generally do not harbor ETV6 rearrangements. Cases of cutaneous neoplasms with histologic features identical to secretory carcinoma of the breast and salivary glands were identified from the consultation files of 3 academic medical institutions. Immunohistochemistry was performed for S100 protein, mammaglobin and STAT5a. Break-apart fluorescence in situ hybridization was used evaluate for disruption of the ETV6 gene. Six cases of cutaneous secretory carcinoma were identified. The tumors arose in 4 women and 2 men, ranging from 24 to 71 years in age (mean, 47 y). The carcinomas presented in the skin of the axilla (n=4), ventral neck (n=1), and cheek (n=1). The tumors arose in the superficial dermis in association with adnexal structures. None of the patients had a prior or concurrent breast or salivary gland tumor. They were histologically characterized by well-circumscribed but unencapsulated proliferations of bland, eosinophilic cells arranged in microcysts and follicles with intraluminal secretions. Ectopic breast or salivary gland tissue was not identified. The cases were diffusely positive for S100 protein (6 of 6), mammaglobin (6 of 6), and STAT5a (5 of 5). All 6 cases harbored rearrangements of ETV6. All tumors were treated by simple excision alone. No recurrences or metastases developed in the 2 cases with follow-up. Secretory carcinoma of the skin represents a phenotypic, immunohistochemical, and genetic counterpart to secretory carcinoma of the breast and salivary glands. This tumor entity is less anatomically restricted than previously supposed.

A Rare Case of a Pilar Cyst With Ductal Differentiation.

Pilar cysts are common squamous-lined cysts that typically occur on the scalp. They are believed to arise from the isthmus of anagen hairs or from the sac surrounding catagen and telogen hairs. The authors describe a rare case of a pilar cyst with prominent ductal differentiation, presumably of eccrine derivation. Sweat duct differentiation has been described in a myriad of cutaneous neoplasms and rarely within epidermoid cysts. The authors could only find one other case in the literature describing a pilar cyst with sebaceous and apocrine differentiation. The clinicopathologic findings are described here.

Keratoacanthoma and squamous cell carcinoma are distinct from a molecular perspective.

Keratoacanthoma is a controversial entity. Some consider keratoacanthoma as a variant of squamous cell carcinoma, whereas others see it as a distinct self-resolving squamoproliferative lesion. Our objective is to examine the relationship of keratoacanthoma with squamous cell carcinoma and normal skin by using DNA microarrays. DNA microarray studies were performed on formalin-fixed and paraffin-embedded blocks from ten cases of actinic keratoacanthoma utilizing the U133plus2.0 array. These results were compared with our previously developed microarray database of ten squamous cell carcinoma and ten normal skin samples. Keratoacanthoma demonstrated 1449 differentially expressed genes in comparison with squamous cell carcinoma (>5-fold change: P<0.01) with 908 genes upregulated and 541 genes downregulated. Keratoacanthoma showed 2435 differentially expressed genes in comparison with normal skin (>5-fold change: P<0.01) with 1085 genes upregulated and 1350 genes downregulated. The most upregulated genes, comparing keratoacanthoma with normal skin included MALAT1, S100A8, CDR1, TPM4, and CALM1. The most downregulated genes included SCGB2A2, DCD, THRSP, ADIPOQ, adiponectin, and ADH1B. The molecular biological pathway analysis comparing keratoacanthoma with normal skin showed that cellular development, cellular growth and proliferation, cell death/apoptosis, and cell cycle pathways are prominently involved in the pathogenesis of keratoacanthoma. The most enriched canonical pathways were clathrin-mediated endocytosis signaling, molecular mechanisms of cancer and integrin signaling. The distinctive gene expression profile of keratoacanthoma reveals that it is molecularly distinct from squamous cell carcinoma. The molecular pathways and genes differentially expressed in comparing keratoacanthoma with normal skin suggest that keratoacanthoma is a neoplasm that can regress due to upregulation of the cell death/apoptosis pathway.

Malignant melanoma with neural differentiation: an exceptional case report and brief review of the pertinent literature.

: The term neurotropic melanoma has been used to refer to malignant melanoma with associated infiltration of nerve or "neural differentiation"--that is, melanoma cells exhibiting cytological characteristics of nerve cells. Historically, neurotropic melanoma has generally been discussed within the context of desmoplastic melanoma. We report an exceptional case of melanoma notable for a very well-differentiated neural component that was contiguous with obvious overlying melanoma. After careful consideration of all pertinent histological features, the overall diagnostic impression was that of melanoma with associated "malignant neurotization." We have not encountered a previously reported case with such a well-differentiated neural component. The following article details our exceptional case of melanoma with "malignant neurotization" and presents a discussion of the differential diagnosis and brief review of the pertinent literature.

Reticulin and NM23 staining in the interpretation of lymph nodal nevus rests.

Melanocytic nevus rests in lymph nodes are a known diagnostic challenge, especially in patients with a history of melanoma. Reticulin and NM23 have been studied in this context. The pattern of reticulin staining in melanomas surrounds groups/nests of melanocytes but individual cells in benign nevi. NM23, a metastasis-suppressor gene, has an association with metastatic potential in melanomas and some carcinomas. Twenty-eight cases (14 cases of metastatic melanoma to lymph nodes and 14 cases of lymph node nevus rests, all confirmed with Melan-A staining) were stained with reticulin and NM23. The pattern of reticulin staining was reported as surrounding groups if staining was noted in approximately 5-10 melanocytes in greater than 50% of the lesion but was otherwise reported as surrounding individual melanocytes. Cytoplasmic staining was considered to represent reactivity for NM23. Reticulin staining around groups of melanocytes was identified in all 14 cases of metastatic melanoma. Regarding nodal nevus rest cases, 12 of 14 cases (86%) demonstrated staining around individual melanocytes, whereas in 2 cases, reticulin surrounded melanocytic groups. NM23 staining was equivocal in all cases. Reticulin staining reliably invests groups of melanocytes in cases of metastatic melanoma, whereas in nodal nevus rests, it predominantly surrounds individual melanocytes. NM23 demonstrated no discriminatory value in this analysis. In cases in which a collection of melanocytes is present within a lymph node, reticulin deposition around individual melanocytes supports a diagnosis of lymph nodal nevus rest.

Mimics of cutaneous lymphoma: report of the 2011 Society for Hematopathology/European Association for Haematopathology workshop.

The Society for Hematopathology and European Association for Haematopathology workshop, from October 27 to 29, 2011, in Los Angeles, CA, exhibited many exemplary skin biopsy specimens with interesting inflammatory changes mimicking features of cutaneous lymphoma. This article reviews features observed in cutaneous lymphoid hyperplasia, cutaneous drug reactions, lupus-associated panniculitis, pityriasis lichenoides, hypereosinophilic syndrome, histiocytic necrotizing lymphadenitis, traumatic ulcerative granuloma with stromal eosinophils, and pigmented purpuric dermatosis, as well as a brief review of the pertinent literature and discussion of submitted conference cases. For the pathologist, it is important to be aware of diagnostic pitfalls as well as the limitations of ancillary testing (eg, clonality studies). Finally, correlation with total clinical information, good communication with clinical colleagues, close clinical follow-up with rebiopsy, and prudent use of laboratory studies are vital and will likely offer the best path toward a correct diagnosis.

Pilot study on "pericytic mimicry" and potential embryonic/stem cell properties of angiotropic melanoma cells interacting with the abluminal vascular surface.

The interaction of tumor cells with the tumor vasculature is mainly studied for its role in tumor angiogenesis and intravascular metastasis of circulating tumor cells. In addition, a specific interaction of tumor cells with the abluminal surfaces of vessels, or angiotropism, may promote the migration of angiotropic tumor cells along the abluminal vascular surfaces in a pericytic location. This process has been termed extravascular migratory metastasis. The abluminal vascular surface may also provide a vascular niche inducing or sustaining stemness to angiotropic tumor cells. This pilot study investigated if angiotropic melanoma cells might represent a subset population with pericytic and embryonic or stem cell properties. Through microarray analysis, we showed that the interaction between melanoma cells and the abluminal surface of endothelial cells triggers significant differential expression of several genes. The most significantly differentially expressed genes have demonstrated properties linked to cancer cell migration (CCL2, ICAM1 and IL6), cancer progression (CCL2, ICAM1, SELE, TRAF1, IL6, SERPINB2 and CXCL6), epithelial to mesenchymal transition (CCL2 and IL6), embryonic/stem cell properties (CCL2, PDGFB, EVX1 and CFDP1) and pericytic recruitment (PDGFB). In addition, bioinformatics-based analysis of the differentially expressed genes has shown that the most significantly enriched functional groups included development, cell movement, cancer, and embryonic development. Finally, the investigation of pericyte/mesenchymal stem cells markers via immunostaining of human melanoma samples revealed expression of PDGFRB, NG2 and CD146 by angiotropic melanoma cells. Taken together, these preliminary data are supportive of the "pericytic mimicry" by angiotropic melanoma cells, and suggest that the interaction between melanoma cells and the abluminal vascular surface induce differential expression of genes linked to cancer migration and embryonic/stem cell properties.

Differential gene expression profiling of primary cutaneous melanoma and sentinel lymph node metastases.

Limited understanding of molecular mechanisms of metastasis in melanoma contributes to the absence of effective treatments. Increased knowledge of alterations in genes that underpin critical molecular events that lead to metastasis is essential. We have investigated the gene expression profiles of primary melanomas and melanoma metastases in sentinel lymph nodes. A total of 19 samples (10 primary melanomas and 9 sentinel lymph node metastases) were evaluated. Melanoma cells were dissected from tissue blocks. Total mRNA was isolated, amplified, and labeled using an Ambion Recover All Total Nucleic Acid Isolation kit, Nu-GEN WT-Ovation formalin-fixed, paraffin-embedded RNA Amplification System, and FL-Ovation cDNA Biotin Module V2, respectively. Samples were hybridized to the Affymetrix Gene Chip Human U133 Plus 2.0 Array. Data were analyzed using Partek Genomics Suite Version 6.4. Genes selected showed ≥2-fold difference in expression and P<5.00E-2. Validation studies used standard immunohistochemical assays. Hierarchical clustering disclosed two distinct groups: 10 primary melanomas and 9 sentinel lymph node metastases. Gene expression analysis identified 576 genes that showed significant differential expression. Most differences reflected decreased gene expression in metastases relative to primaries. Reduced gene expression in primaries was less frequent and less dramatic. Genes significantly increased or decreased in sentinel lymph node metastases were active in cell adhesion/structural integrity, tumor suppression, cell cycle regulation, and apoptosis. Validation studies indicate that MAGEC1 (melanoma antigen family C1) and FCRL1 (Fc receptor-like 1) are involved in melanoma progression. There are striking differential gene expression patterns between primary and nodally metastatic melanomas. Similar findings were seen with autologous paired primary melanomas and sentinel lymph node metastases, supporting involvement of these gene alterations in evolution of metastases. With further study, it may be possible to determine the exact sequence of molecular events that underlie melanoma metastases.

Cutaneous ciliated cyst on the finger: a cutaneous mullerian cyst.

As previously recognized by various authors, "cutaneous ciliated cyst" is a confusing term. Typically, the term refers to rare cystic lesions, commonly found on the lower limbs of women in their reproductive years. To date, 40 cases diagnosed as "cutaneous ciliated cyst" have been reported in the literature. Histologically, the cysts are composed of a simple layer of ciliated columnar cells along with nonciliated columnar cells, cuboidal cells, and round "peg-like" cells, resembling fallopian tube epithelium. This histology has been described in cysts found in males and females and in locations other than the lower limbs. Controversy has thus arisen over the etiology of these lesions, with some believing that the cysts arise from heterotopic Mullerian rests and others advocating for ciliated metaplasia of eccrine glands. We herein describe the first case of cutaneous ciliated cyst of Mullerian origin occurring on the dorsal thumb of a 16-year-old female. A review of literature shows that 2 groups of cysts are covered under the umbrella term "cutaneous ciliated cysts." We thus propose the abandonment of the confusing term "cutaneous ciliated cyst" and the adoption of "cutaneous Mullerian cysts" for estrogen receptor/progesterone receptor-positive lesions resembling simple fallopian tube epithelium and "Cutaneous ciliated eccrine cyst" for estrogen receptor/progesterone receptor-negative lesions usually occurring in males, which are immunohistochemically compatible with an eccrine origin.

Onychomatricoma: a case report with literature review.

Onychomatricoma (OM) is a fibroepithelial tumor of nail matrix that occurs in the digits of both the hands and feet. This was first reported by Baran and Kint. They initially described 3 cases, all of which demonstrated a filamentous tumor of matrix tissue that resulted in a thickened funnel-shaped nail. Although apparently benign, it is subject to recurrence, and long-term follow-up is recommended because it is not known whether there is a conversion to malignancy. Even though this neoplasm was first described more than 18 years ago, there remains a dearth of case reports (currently fewer than 50) in the literature. This is a single case report and literature review. Levels of Evidence : Therapeutic, Level IV.

Plasma cell balanitis presenting in a patient with a history of syphilis.

Plasma cell balanitis (PCB), also knows as Zoon balanitis, is a benign asymptomatic but chronic and erosive inflammatory condition of the glans penis and prepuce that generally affects uncircumcised men in later years. Clinical presentation involves a single, shiny, well defined reddish patch. We describe the first case of PCB ever reported in a patient with a previous history of syphilis, and include a review of the current literature. A 57-year-old Hispanic man with a remote history of syphilis presented with a 6-month nonhealing, granulating ulcer of the foreskin and glans penis that had been repeatedly mistaken for syphilis and treated unsuccessfully with circumcision 3 weeks previously. Biopsy of the glans penis demonstrated sections with denuded chronic granulation tissue showing a fibrotic stroma with numerous blood vessels and a mixed inflammatory infiltrate including scattered plasma cells. It is important to differentiate PCB from a syphilitic chancre in a patient presenting with a nonhealing penile lesion. This case report demonstrates that these entities may be seen in the same patient at different times.

Potentially useful markers for desmoplastic melanoma: an analysis of KBA.62, p-AKT, and ezrin.

Desmoplastic melanoma (DM) represents only a small portion of newly diagnosed melanoma cases but can be a significant diagnostic challenge for dermatopathologists. Immunohistochemical stains are often useful to confirm the diagnosis; however, DM is notorious for not expressing most of the melanocytic markers other than S100. Recent studies have suggested several new markers, which may be promising in the diagnosis of DM. KBA.62 is a relatively new antimelanoma monoclonal antibody, which has not been well characterized in DM. Ezrin and p-Akt are additional markers, which have been shown to be involved in cell survival and proliferation. We collected 12 cases of DM and 18 cases of other lesions that could be included in the differential diagnosis. The H&E sections were reviewed, and immunohistochemical stains for KBA.62, p-AKT, and Ezrin were performed. Seventy-five percent of the DM cases (9 of 12) demonstrated positive staining (>5% of tumor cells staining) with KBA.62, with an average of 39% of cells staining. One hundred percent of the DM cases (12 of 12) demonstrated positive staining with Ezrin, with an average of 49% of tumor cells staining. Seventy-five percent of the DM cases (9 of 12) demonstrated positive staining with p-Akt, with an average of 49% of cells staining. KBA.62 and Ezrin demonstrated statistically significant increased staining of DM cases compared with the other lesions (P = 0.05 and P = 0.007, respectively), although it was not useful in distinguishing DM versus malignant peripheral nerve sheath tumor, whereas p-Akt showed no significant differences in staining between DM and the other cases. These findings suggest that KBA.62 may be a useful marker in confirming the diagnosis of DM.

Defining the origins of Ras/p53-mediated squamous cell carcinoma.

The precise identity of cancer cells of origin and the molecular events of tumor initiation in epidermal squamous cell carcinoma (SCC) are unknown. Here we show that malignancy potential is related to the developmental capacity of the initiating cancer cell in a genetically defined, intact, and inducible in vivo model. Specifically, these data demonstrate that SCCs can originate from inside the hair follicle stem cell (SC) niche or from immediate progenitors, whereas more developmentally restricted progeny, the transit amplifying (TA) cells, are unable to generate even benign tumors in the same genetic context. Using a temporal model of tumorigenesis in situ, we highlight the phenotypes of cancer progression from the hair follicle SC niche, including hyperplasia, epithelial to mesenchymal transition, and SCC formation. Furthermore, we provide insights into the inability of hair follicle TA cells to respond to tumorigenic stimuli.

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.

Unusual palisading and necrotizing granulomas associated with a lubricating agent used in lipoplasty.

Palisading granulomas with necrobiosis are frequently encountered in dermatopathology, with granuloma annulare, necrobiosis lipoidica diabeticorum, and rheumatoid nodule being the most frequently rendered diagnoses. We report a series of 9 patients who developed palisading, necrobiotic, and necrotizing granulomas, associated with the presence of foreign material introduced through the use of a lubricating agent containing a copolymer (Carbopol 934) for liposuction. The patients ranged in age from 29 to 54 years old and presented with multiple, disfiguring, and nonhealing wounds at sites where lipoplasty had been performed. All specimens showed similar histologic findings, with the formation of palisading granulomas around extensive areas of necrobiosis with foci of true necrosis. Spaces containing minute fragments of crystalloid-appearing foreign material, birefringent with polarized light, were also identified. Special stains including acid fast, Gram, Giemsa, and/or periodic acid-Schiff were negative for organisms in all cases, as were cultures performed in 5 cases. Given the presence of foreign material and true necrosis, these findings were inconsistent with granuloma annulare, necrobiosis lipoidica diabeticorum, or rheumatoid nodule and were interpreted as a unique reaction to the foreign material. Therefore, this seems to be a distinct reaction pattern that has not been previously reported in the literature and may be important to include in the differential diagnosis in patients with necrotizing granulomatous disease.

CD30 positive anaplastic large-cell lymphoma mimicking Langerhans cell histiocytosis.

The presence of CD 1a+ dendritic cells (DC) has been well described in T-cell lymphoproliferative disorders, and the presence of large numbers of DCs has rarely been reported as a mimicker of Langerhans cell histiocytsis (LCH). We present the case of a 56-year-old female with a solitary nodule on the chin whose case was referred to our institution for confirmation of the diagnosis of LCH. Skin biopsy showed an ulcerated nodule containing a wedge-shaped infiltrate comprised of large atypical cells and cells with prominent grooved nuclei. The constellation of histologic and immunologic features favored a CD30 lymphoproliferative disorder of T-cell lineage even though there were accompanying numerous dendritic histiocytes and CD1a positive Langerhans cells. The sheets of CD30 positive atypical lymphoid cells which express T-cell markers were consistent with CD30 positive lymphoproliferative disease and favor CD30 positive anaplastic large-cell lymphoma (ALCL) over Langerhans histiocytosis. The absence of Anaplastic Lymphoma Kinase (ALK) staining favored a primary cutaneous origin. This case signifies a CD 30+ ALCL of the skin which histopathologically mimics a LCH. Ezra N, Van Dyke GS, Binder SW. CD30 positive anaplastic large-cell lymphoma (ALCL) mimicking Langerhans cell histiocytosis (LCH).