CD30 in Cutaneous Pathology

ABSTRACT

The discovery of CD30 as a diagnostic marker was essential in the identification of not only some lymphomas but also many other solid tumors and benign reactive conditions. Many CD30+ cutaneous disorders and tumors have been categorized since the identification of the marker. With the design of targeted therapies against CD30+ tumoral cells, the interest in CD30 determination was not only diagnostic but also mainly therapeutic. In this article, we explore the historical aspects of the discovery of CD30 and examine the main CD30-related cutaneous pathology, susceptible of anti-CD30 modern treatments.

Vascular Malformations: A Histopathologic and Conceptual Appraisal

In the field of vascular anomalies, distinguishing between vascular malformations and tumors has become crucial for a correct therapeutic approach. However, the differential diagnosis between these two groups is not always well explained in classical texts, mainly because many vascular malformations are still known with old names that suggest a tumoral nature. Also, genetic and pathogenic knowledge of these entities has greatly increased in recent decades, so researchers and clinicians now have a better understanding of vascular malformations. In this paper, we present the main histopathological tips to recognize and identify a vascular malformation as such. We also contextualize such information in the clinical and pathogenic knowledge for a better understanding of these entities.

Vascular Malformations: A Histopathologic and Conceptual Appraisal

In the field of vascular anomalies, distinguishing between vascular malformations and tumors has become crucial for a correct therapeutic approach. However, the differential diagnosis between these two groups is not always well explained in classical texts, mainly because many vascular malformations are still known with old names that suggest a tumoral nature. Also, genetic and pathogenic knowledge of these entities has greatly increased in recent decades, so researchers and clinicians now have a better understanding of vascular malformations. In this paper, we present the main histopathological tips to recognize and identify a vascular malformation as such. We also contextualize such information in the clinical and pathogenic knowledge for a better understanding of these entities.

Genetic Studies on a Case of Eruptive Disseminated Spitz Nevus and Review of Other 33 Cases

ABSTRACT

Eruptive disseminated Spitz nevus is an uncommon presentation of Spitz nevi. Only a few tens of cases have been published and only 6 of them have genetic studies. We present an additional case of a 29-year-old woman with dozens of Spitz nevi which had appeared since she was aged 10 years. The nevi were located on arms, inner thighs, legs, and buttocks. Nine of them were biopsied. Four presented severe atypia. Immunohistochemistry was performed on 5 of the biopsied specimens and was negative for PRAME, ROS-1, PDL-1, pan-TRK, and ALK. Molecular studies on the largest lesion demonstrated no NTRK1, NTRK2, or NTRK3 fusions. FISH study for PTEN showed no alteration in that same lesion. Next-generation sequencing was also negative for any detectable mutations in numerous genes analyzed. In conclusion, it seems reasonable to be cautious when evaluating atypia, even if severe, in cases of eruptive disseminated Spitz nevus.

Primary Idiopathic Cutaneous Intestinal Metaplasia: First Case

ABSTRACT

Cutaneous intestinal either metaplasia or ectopia has mostly been described around intestinal stomas or in patients with Crohn disease. In this study, we described a unique case of cutaneous metaplasia on the elbow of a 25-year-old man who had a clinical history of epidermolysis bullosa simplex, but had no history of any gastrointestinal disease. The lesion had been clinically stable for 5 years. Histopathologically, the epithelium showed many columnar cells with mucinous cytoplasm, with no atypia or mitoses. The proliferation rate was low (7% by Ki67). The metaplastic areas expressed epithelial membrane antigen, carcinoembryonic antigen, cytokeratin 7, MUC5AC, MUC2, and Cyclin-D1.

Numerous Recurring Angiolipomas in a Patient with a History of Hepatitis B and Hepatocellular Carcinoma

Angiolipomas are benign vascularized variants of lipomas. They can present as a solitary lesion or in clusters, occurring equally in both male and female patients, often after puberty. Angiolipomas are uncommon and few cases have been documented, especially cases with very high counts or multiple clusters. The clinical presentation is similar to that of lipomas; however, they have distinct histological characteristics with varying levels of vascularity and microthrombi intimately associated with mature adipocytes. Angiolipomas can be further classified as non-infiltrating or infiltrating depending on their encapsulation and relation to other structures. Although the etiology is unknown, angiolipomas have been shown to be associated with systemic disease, such as diabetes mellitus and HIV, and a link to HIV protease inhibitors has also been documented in several case reports. However, no cases have been reported in patients with liver disease before. Herein, we present a rare and unusual case of a male patient with a history of hepatitis B and hepatocellular carcinoma and at least 68 angiolipomas.

Thickening of the basement membrane as a diagnostic sign of mycosis fungoides

The epidermal basement membrane (BM) is readily identified on skin biopsy specimens stained with periodic acid-Schiff (PAS) and PAS with diastase (PAS-D). Thickening of BM can be evidenced in several inflammatory and tumoral conditions. We noticed that most of our biopsy specimens of mycosis fungoides (MF) showed thickening of the BM. We decided to retrospectively study BM thickness in 27 biopsy specimens of MF and compare them with 27 cutaneous biopsy specimens of inflammatory diseases. We studied PAS and PAS-D stains in all cases and we measured BM thickness with an ocular micrometer. Cases were scored in a four-tiered system: 0: no detectable staining; 1+ (mild: < 5 μm); 2+ (moderate: 5-9 μm); and 3+ (prominent: >9 μm). The difference between both groups (MF vs controls) was highly significant for BM thickness values by both one- and two-tailed t tests (P < 0.0006). While only 3 biopsy specimens from the controls (11.11%) showed areas of 3+ thickening, 12 biopsy specimens of MF (44.44%) showed areas of 3+ thickening, and most cases showed diffuse, at least 2+ thickening, while the controls showed more segmental, mostly 1 or 2+ staining. We conclude that thickening of BM can be useful in the differential diagnosis with inflammatory conditions.

Clear cell atypical fibroxanthoma: a case report and review of the literature

Atypical fibroxanthoma (AFX) is a group of cutaneous tumors characterized by a population of fusiform, epithelioid and pleomorphic cells. Clinically, AFX is commonly found on the head and neck of older adults as a solitary ulcerated nodule. Clear cell atypical fibroxanthoma is a very rare variant of AFX, with only 13 cases reported to date. The differential diagnoses often include dermal neoplasms composed of clear cells, such as squamous cell carcinoma, basal cell carcinoma, metastatic renal cell carcinoma and balloon cell malignant melanoma. These diagnoses can be ruled out by the typical immunohistochemical profile of clear cell AFX, which is negative for specific epithelial and melanocytic markers. Herein, we describe a rare and unusual case of clear cell AFX arising on the ear of a relatively young adult patient. Histologically, the dermis was completely replaced by an atypical population of vacuolated cells with numerous atypical mitoses. Immunohistochemical stains were negative forpancytokeratin, CK5/6, CK7, and p63 S100 and Melan-A stains. CD10 and CD68 stains were positive, making the findings consistent with the diagnosis of clear cell atypical fibroxanthoma.

Non-HIV-related Kaposi sarcoma in 2 Hispanic patients arising in the setting of chronic venous insufficiency

Kaposi sarcoma (KS) is a vascular neoplasm associated with human herpesvirus 8 (HHV-8) infection that can be confused with the clinical and histological findings of chronic venous insufficiency. Definitive diagnosis of KS can only be achieved by performing a polymerase chain reaction for HHV-8 or by immunostaining for the HHV-8 antigen. We describe 2 unusual clinical presentations of KS in the setting of chronic venous insufficiency with clinical and histologic features consistent with stasis dermatitis but positive HHV-8 immunostaining. Both patients had no known risk factors for KS. We propose the possibility that these cases may represent a new clinical variant of KS that may become more prevalent over time. Further studies are needed to identify the risk factors involved. Meanwhile, skin biopsy with HHV-8 testing may be warranted for violaceous patches and plaques arising on the legs in the setting of chronic venous insufficiency, especially in patients who are unresponsive to treatment.

Up-regulated Dicer expression in patients with cutaneous melanoma

BACKGROUND

MicroRNAs (miRNAs) are small non-coding RNAs (18-24 nucleotides) that have recently been shown to regulate gene expression during cancer progression. Dicer, a central enzyme in the multi-component miRNA biogenesis pathway, is involved in cutting precursor miRNAs to functionally mature forms. Emerging evidence shows that Dicer expression is deregulated in some human malignancies and it correlates with tumor progression, yet this role has not yet been investigated in skin cancers.

METHODS AND FINDINGS

Using an anti-human monoclonal antibody against Dicer and immunohistochemistry, we compared the expression of Dicer protein among 404 clinically annotated controls and skin tumors consisting of melanocytic nevi (n = 71), a variety of melanomas (n = 223), carcinomas (n = 73) and sarcomas (n = 12). Results showed a cell-specific up-regulated Dicer in 81% of cutaneous, 80% of acrolentiginous and 96% of metastatic melanoma specimens compared to carcinoma or sarcoma specimens (P<0.0001). The expression of Dicer was significantly higher in melanomas compared to benign melanocytic nevi (P<0.0001). In patients with cutaneous melanomas, Dicer up-regulation was found to be significantly associated with an increased tumor mitotic index (P = 0.04), Breslow's depth of invasion (P = 0.03), nodal metastasis (P = 0.04) and a higher American Joint Committee on Caner (AJCC) clinical stage (P = 0.009). Using western blot analysis, we confirmed the cell-specific up-regulation of Dicer protein in vitro. A pooled-analysis on mRNA profiling in cutaneous tumors showed up-regulation of Dicer at the RNA level in cutaneous melanoma, also showing deregulation of other enzymes that participate in the biogenesis and maturation of canonical miRNAs.

CONCLUSIONS

Increased Dicer expression may be a clinically useful biomarker for patients with cutaneous melanoma. Understanding deregulation of Dicer and its influence on miRNA maturation is needed to predict the susceptibility of melanoma patients to miRNA-based therapy in the future.

Modeling inducible human tissue neoplasia identifies an extracellular matrix interaction network involved in cancer progression

To elucidate mechanisms of cancer progression, we generated inducible human neoplasia in three-dimensionally intact epithelial tissue. Gene expression profiling of both epithelia and stroma at specific time points during tumor progression revealed sequential enrichment of genes mediating discrete biologic functions in each tissue compartment. A core cancer progression signature was distilled using the increased signaling specificity of downstream oncogene effectors and subjected to network modeling. Network topology predicted that tumor development depends on specific extracellular matrix-interacting network hubs. Blockade of one such hub, the beta1 integrin subunit, disrupted network gene expression and attenuated tumorigenesis in vivo. Thus, integrating network modeling and temporal gene expression analysis of inducible human neoplasia provides an approach to prioritize and characterize genes functioning in cancer progression.

Module map of stem cell genes guides creation of epithelial cancer stem cells

Self-renewal is a hallmark of stem cells and cancer, but existence of a shared stemness program remains controversial. Here, we construct a gene module map to systematically relate transcriptional programs in embryonic stem cells (ESCs), adult tissue stem cells, and human cancers. This map reveals two predominant gene modules that distinguish ESCs and adult tissue stem cells. The ESC-like transcriptional program is activated in diverse human epithelial cancers and strongly predicts metastasis and death. c-Myc, but not other oncogenes, is sufficient to reactivate the ESC-like program in normal and cancer cells. In primary human keratinocytes transformed by Ras and I kappa B alpha, c-Myc increases the fraction of tumor-initiating cells by 150-fold, enabling tumor formation and serial propagation with as few as 500 cells. c-Myc-enhanced tumor initiation is cell-autonomous and independent of genomic instability. Thus, activation of an ESC-like transcriptional program in differentiated adult cells may induce pathologic self-renewal characteristic of cancer stem cells.

Cutaneous involvement by angioimmunoblastic T-cell lymphoma: a unique histologic presentation, mimicking an infectious etiology

Angioimmunoblastic T-cell lymphoma (AILT) is an aggressive peripheral T-cell lymphoma that is frequently accompanied by a cutaneous eruption. The cutaneous findings most commonly consist of a maculopapular eruption on the trunk. However, purpura, infiltrated or urticarial plaques, papulovesicular lesions, nodules, and erythroderma have also been reported. Histologic findings in the lymph node are characteristic, while those in the skin may show one of four patterns. Here, we review the previously reported histologic patterns and present a case of AILT involving the skin with a unique histologic appearance of necrotizing granulomas with abundant histiocytes and eosinophils, mimicking an infectious etiology.

Evaluation of single versus multiple cryogen spray cooling spurts on in vitro model human skin

Many commercially available dermatologic lasers utilize cryogen spray cooling for epidermal protection. A previous tissue culture study demonstrated that single cryogen spurts (SCS) of 80 ms or less were unlikely to cause cryo-injury in light-skinned individuals. More recently, multiple cryogen spurts (MCS) have been incorporated into commercial devices, but the effects of MCS have not been evaluated. The aim was to study an in vitro tissue culture model and the epidermal and dermal effects of SCS vs patterns of shorter MCS with the same preset total cryogen delivery time (Deltat(c)) and provide an explanation for noted differences. Four different spurt patterns were evaluated: SCS: one 40-ms cryogen spurt; MCS2: two 20-ms cryogen spurts; MCS4: four 10-ms cryogen spurts; MCS8: eight 5-ms cryogen spurts. Actual Deltat(c) and total cooling time (Deltat(Total)) were measured for each spurt pattern. RAFT tissue culture specimens were exposed to cryogen spurt patterns and biopsies were taken immediately and at days 3 and 7. Actual Deltat(c) was increased while Deltat(Total) remained relatively constant as the preset Deltat(c) of 40 ms was delivered as shorter MCS. Progressively more epidermal damage was noted with exposure to the MCS patterns. No dermal injury was noted with either SCS or MCS. For a constant preset Deltat(c) of 40 ms, delivering cryogen in patterns of shorter MCS increased the actual Deltat(c) and consequently the observed epidermal cryo-injury as compared to an SCS.

Cyclical Cushing syndrome presenting in infancy: an early form of primary pigmented nodular adrenocortical disease, or a new entity?

Cushing syndrome is uncommon in childhood and rare in infancy. We report the case of a 3-yr-old child who presented with symptoms of Cushing syndrome beginning shortly after birth. Her hypercortisolemia was cyclical, causing relapsing and remitting symptoms, which eventually led to suspicions of possible Munchausen syndrome by proxy. Investigation at the National Institutes of Health excluded exogenous administration of glucocorticoids and indicated ACTH-independent Cushing syndrome. Paradoxical response to dexamethasone stimulation (Liddle's test) suggested a diagnosis of primary pigmented nodular adrenocortical disease (PPNAD). After bilateral adrenalectomy, both glands showed micronodular adrenocortical hyperplasia, but histology was not consistent with typical PPNAD. DNA analysis of the coding sequences of the PRKAR1A gene (associated with PPNAD and Carney complex) and the GNAS gene (associated with McCune-Albright syndrome) showed no mutations. We conclude that hypercortisolemia in infancy may be caused by micronodular adrenocortical hyperplasia, which can be cyclical and confused with exogenous Cushing syndrome. A paradoxical rise of glucocorticoid excretion during Liddle's test may delineate these patients. Infantile micronodular disease has some features of PPNAD and may represent its early form; however, at least in the case of the patient reported here, micronodular hyperplasia was not caused by coding mutations of the PRKAR1A or GNAS genes or associated with typical histology or any other features of Carney complex or McCune-Albright syndrome and may represent a distinct entity.