A Comparison of Preferentially Expressed Antigen in Melanoma Immunohistochemistry and Diagnostic Gene Expression-Profiling Assay in Challenging Melanocytic Proliferations.

ABSTRACT: Most melanocytic tumors are classified as benign or malignant based on clinical morphology, histology, and immunohistochemical (IHC) analysis. A subset of more challenging cases with ambiguous features may require further evaluation with established ancillary diagnostic molecular studies, including fluorescence in situ hybridization and/or single nucleotide polymorphism array, to increase diagnostic certainty. More recently, a diagnostic gene expression-profiling (GEP) assay and an IHC stain for the detection of PRAME (PReferentially expressed Antigen in MElanoma) have been developed. The use of PRAME IHC has been validated in cases of unequivocal and ambiguous melanocytic proliferations via comparing results with fluorescence in situ hybridization and/or single nucleotide polymorphism array. A study comparing performance metrics of PRAME IHC and diagnostic GEP has not been previously published. Herein, we evaluated the use of PRAME IHC in 55 melanocytic tumors with challenging histomorphology by comparing the results with diagnostic GEP and final histomorphologic diagnosis. Intertest agreement occurred in 88% of cases. PRAME IHC supported the final diagnosis in 89% of cases with a sensitivity of 79%, specificity of 95%, and positive predictive value of 88.2%. GEP agreed with the final diagnosis in 88% of cases with a sensitivity of 65%, 97% specificity, and positively predicted melanoma in 91.7% of cases. Because the results of this study align with past publications evaluating the performance metrics of PRAME IHC, showing it to be as sensitive as and more cost effective than all other ancillary molecular tests, we propose the use of PRAME IHC as the optimal first-line diagnostic tool for ambiguous melanocytic proliferations.

Mpox Case Presenting With Genital Lesions and Proctitis.

ABSTRACT: Monkeypox (Mpox) is a zoonotic Orthopoxvirus of the Poxviridae family, endemic to Africa. In August 2022, the US government declared it an emergency because of the worldwide spread. Traditionally, Mpox infection spreads through contact with infected animals. However, the 2022 outbreak Centers for Disease Control and Prevention (CDC) data note that 94% of cases had recent male-to-male sexual or close intimate contact, suggesting a novel sexual transmission. In this article, we report a 39-year-old HIV-positive man presenting with a diffuse cutaneous rash, perianal pain, and bloody stool of 2-week duration. A medical history includes intravenous drug use and multiple sexual partners. Physical examination revealed umbilicated, tan-colored, crusted cutaneous papules scattered across the face, trunk, and genital regions. Perianal lesion biopsy showed an acanthotic epidermis with spongiosis, ballooning degeneration of keratinocytes, and the formation of multinucleated syncytial keratinocytes. A dermal superficial/lichenoid mixed inflammatory cell infiltrate with multinucleated giant cells was noted. Perianal lesion polymerase chain reaction (PCR) was positive for Mpox. Colonoscopy revealed a 3-cm circumferential rectal ulcer with gray exudate and necrosis. A rectal ulcer biopsy showed an ulcerated mucosa with acute proctitis and necrosis. There were scattered macrophages with intranuclear inclusion and glassy vacuolization, and Mpox infection was confirmed by immunostaining with a Mpox-specific anti-Vaccinia virus antibody.

Acute generalized exanthematous pustulosis associated with clindamycin in a patient with Hailey-Hailey disease.

A 61-year-old African-American female with moderately controlled Hailey-Hailey disease (HHD) presents to the emergency department with a rash and fever. One day prior to her presentation, she was started on oral clindamycin for a tooth extraction procedure. Her physical examination shows diffuse erythema on the trunk and extremities with multiple nonfollicular pustules. A punch biopsy of her upper extremity revealed intraepidermal acantholysis, neutrophilic spongiosis, and subcorneal pustules. The perivascular and interstitial superficial dermal infiltrate is mixed and composed of predominantly neutrophils, with lymphocytes and rare eosinophils. These findings suggest a superimposed acute generalized exanthematous pustulosis (AGEP) in the background of HHD. AGEP is a potentially severe cutaneous condition characterized by the abrupt onset of numerous nonfollicular pustules in a background of pruritic edematous erythroderma. To date, only two case reports have described AGEP in patients with HHD. Early diagnosis of AGEP is essential to initiate prompt and aggressive systemic therapy, prompt medication cessation, close monitoring for end-organ damage, and improve overall morbidity and mortality.

Solitary Vulvar Syringoma With Deep Extension; Potential for Misdiagnosis as the Microcystic Adnexal Carcinoma (MAC).

ABSTRACT: A 43-year-old woman presented with a palpable, pruritic, minimally painful right vulvar lesion. Physical examination revealed approximately 2.0-cm tender nodule at 70' clock in the right labia majora. Histological sections of the excision specimen showed an unremarkable epidermis with large, well-circumscribed dermal proliferation with extension to the reticular dermis. Within this proliferation are small solid and ductal structures relatively evenly distributed in the sclerotic stroma. The epithelial elements consisted of monomorphous cuboidal cells and assumed round, oval, curvilinear, or have other peculiar geometric shapes, including "comma-like" or "tadpole"-like configurations. The tumor cells were positive for CEA, EMA, and estrogen receptor and negative for progesterone receptor. The clinical presentation and the deep extension of the tumor were similar to the microcystic adnexal carcinoma. Although a syringoma generally presents with multiple lesions and usually involves the superficial dermis, a syringoma with deep extension was favored based on the lack of follicular differentiation, atypia, mitoses, and perineural invasion. Microcystic adnexal carcinoma and syringoma have a morphologic overlap and are misdiagnosed in 30% of the cases. Thus, it is exceptionally important for pathologists to be aware of and be able to distinguish these entities. To the best of our knowledge, this is the first case of a solitary, painful vulvar syringoma with deep extension.

Primary Cutaneous Ewing Sarcoma of the Scalp With Metastasis to the Lung: An Unusual Manifestation During Pregnancy.

ABSTRACT: A 32-year-old G2P1L1 (5 months pregnant) woman presented with a 3-month history of a slow-growing cystic lesion on her scalp vertex. Similar lesions in the exact location were excised twice in the past with a diagnosis of trichilemmal carcinoma (TC). A biopsy of the scalp lesion showed morphology and immunoprofile consistent with previously diagnosed TC. Staging PET/CT demonstrated a 4.7 cm right upper lobe lung, and a subsequent lung biopsy showed a small, round blue-cell tumor with necrosis, morphologically identical to the prior biopsies from the scalp. Considering the unusual clinical course of TC, a lung biopsy was sent for next-generation sequencing that showed EWSR1-FLI1 (type1) fusion. Additionally, CD99 immunostaining revealed uniform cytoplasmic and membranous staining in the tumor cells. The previous scalp excision specimen was also sent for mutation analysis, which showed EWSR1-FLI1 fusion. In conjunction with clinical history and histological and molecular findings, a definitive diagnosis of primary cutaneous Ewing sarcoma (PCES) with local recurrence and metastasis to the lung was made. We present a case of PCES, which was previously misdiagnosed and treated as TC. This case emphasizes the importance of CD99 in the initial screening of cutaneous small round blue-cell tumors to avoid misdiagnosis from other morphological overlaps. Also, despite its rarity, PCES should be included in the differential diagnosis of small, round, blue cell tumors at cutaneous sites. Our case also exemplifies common biases in medical decision-making, including premature closure and anchoring bias which can result in misdiagnosis or diagnostic delay and associated delay in appropriate management.

Disseminated Protothecosis Due to Prototheca zopfii and Literature Review.

ABSTRACT: Prototheca species are achlorophyllic algae that are a rare cause of infection in humans. It most commonly causes localized cutaneous disease and rarely disseminated infection. Immunocompromised patients have the highest risk of disseminated protothecosis, with a higher mortality rate than localized cutaneous infections. At the species level, infections caused by Prototheca zopfii are reported less frequently than those caused by Prototheca wickerhamii. The diagnosis can be made using histopathology, culture, and molecular testing. There is no definitive evidence for an effective treatment, which currently consists of antifungals (primarily amphotericin B). With only a handful of cases of disseminated protothecosis reported worldwide that are caused by P. zopfii , we herein present an additional case of a postbone marrow transplant patient in the Midwest of the United States.

Mechanic Hands/Hiker Feet in a Patient With Amyopathic Dermatomyositis and Interstitial Lung Disease.

ABSTRACT: A 30-year-old African American woman with a history of interstitial lung disease presented with bilaterally symmetrical, nonpruritic, scaling and fissuring, hyperpigmented, lichenified plaques on her hands and feet. She reported occasional erythema of her face, intermittent erythema, and irritation of her eyes but denied any muscle weakness. A biopsy of the plantar first toe showed hyperkeratosis, striking alternating ortho- and parakeratosis with underlying apoptotic bodies. There was psoriasiform acanthosis without suprapapillary thinning, numerous apoptotic keratinocytes in all layers of the epidermis extending into the corneum that were out of proportion with the minimal interface inflammation. Colloidal iron and Alcian blue stains showed increased dermal mucin deposition. Given the clinical, histopathological, and supportive serological findings (positive anti-KU and anti-SSA), a diagnosis of clinically amyopathic dermatomyositis with mechanic hand/hiker feet (MH/HF) was rendered. The pseudocheckerboard pattern of MH/HF has been previously reported in only 4 patients. The most frequent associations with MH/HF are dermatomyositis and antisynthetase syndrome; however, our patient was negative for antiaminoacyl transfer RNA synthetase antibodies, a required criterion to diagnose antisynthetase syndrome. It is imperative to recognize MH/HF clinically and histopathologically because it may be an early indication of developing dermatomyositis or other connective tissue diseases, which would guide further workup and screening for systemic involvement of the disease, including interstitial lung disease.

A Case of Primary Myelofibrosis With Transformation to Leukemia Cutis.

ABSTRACT: We report an extraordinary case of primary myelofibrosis with transformation to leukemia cutis. A 64-year-old Caucasian man with a history of JAK2-positive primary myelofibrosis presented with erythematous papulonodules on his right lower extremity. A punch biopsy revealed a normal epidermis with an underlying diffuse dermal infiltrate composed of medium-to-large-sized myeloid cells and leukocytes. Neoplastic cells were immunoreactive for LCA, CD34, CD61, CD117, and CD68 and negative for lysozyme, CD20, CD3, myeloperoxidase, and TdT. These findings were consistent with a diagnosis of leukemia cutis. A concurrent bone marrow biopsy demonstrated a markedly fibrotic, hypercellular marrow without a significant increase in blasts. With no morphologic evidence of bone marrow involvement by acute myeloid leukemia, our case suggests that the patient's primary myelofibrosis transformed to leukemia cutis. Our patient died 2 months after the onset of his skin nodules. Our case demonstrates that leukemia cutis should be included in the differential diagnosis for cutaneous nodular lesions in patients with a history of an advanced-stage hematological malignancy.

A comparison of imaging software and conventional cell counting in determining melanocyte density in photodamaged control sample and melanoma in situ biopsies.

BACKGROUND: Objective methods for distinguishing melanoma in situ (MIS) from photodamaged skin (PS) are needed to guide treatment in patients with melanocytic proliferations. Melanocyte density (MD) could serve as an objective histopathological criterion in difficult cases. Calculating MD via manual cell counts (MCC) with immunohistochemical (IHC)-stained slides has been previously published. However, the clinical application of this method is questionable, as quantification of MD via MCC on difficult cases is time consuming, especially in high volume practices. METHODS: ImageJ is an image processing software that uses scanned slide images to determine cell count. In this study, we compared MCC to ImageJ calculated MD in microphthalmia transcription factor-IHC stained MIS biopsies and control PS acquired from the same patients. RESULTS: We found a statistically significant difference in MD between PS and MIS as measured by both MCC and ImageJ software (P < 0.01). Additionally, no statistically significant difference was found when comparing MD measurements recorded by ImageJ vs those determined by the MCC method. CONCLUSION: MD as determined by ImageJ strongly correlates with the MD calculated by MCC. We propose the use of ImageJ as a time-efficient, objective, and reproducible tool to assess MD.

Regulatory T-cells in alopecia areata.

BACKGROUND: Alopecia areata (AA) is believed to have an autoimmune mechanism in which the hair follicles are targeted by CD4+ and CD8+ lymphocytes. Studies investigating the autoimmune mechanism of other cutaneous diseases, including vitiligo, showed that Treg is a component of cutaneous immune privilege. Our study uses immunohistochemical staining in formalin-fixed, paraffin-embedded tissue to examine the percentage of CD4+ FoxP3+ , CD25+ FoxP3+ , and CD8+ FoxP3+ Treg in AA in human specimens. METHODS: Immunohistochemical double staining for CD4+ FoxP3+ , CD25+ FoxP3+ , and CD8+ FoxP3+ was performed on 12 AA cases and 12 other autoimmune and non-autoimmune cutaneous diseases. The frequency of CD4+ FoxP3+ , CD25+ FoxP3+ , and CD8+ FoxP3+ Treg was counted and expressed as a percentage of total CD4+ , CD25+ , and CD8+ lymphocytes, respectively, in order to account for intersample inflammatory response variability. RESULTS: There was a significant reduction in the mean frequency of CD4+ FoxP3+ and CD25+ FoxP3+ in AA when compared to other autoimmune and non-autoimmune cutaneous diseases. CONCLUSION: Treg is significantly lower in AA when compared to other cutaneous diseases. Additionally, this immunohistochemical-staining protocol may be useful to evaluate Treg in formalin-fixed, paraffin-embedded specimens for other cutaneous diseases. Studies examining Treg in AA and other cutaneous diseases may have implications for future interventions.

Actinic Keratosis, Transected: What Lies Beneath?

Evaluation of superficial transected shave biopsies of squamous neoplasms often presents a diagnostic dilemma for the dermatopathologist because of the lack of complete visualization of the base of the epidermis. Fear of "missing" an invasive carcinoma must be balanced with avoidance of overdiagnosis of precancerous actinic keratosis (AK), especially on cosmetically sensitive areas such as the face. If a concern exists that a more invasive component may be present, a diagnosis of AK transected at the base (AKT) will often be rendered to alert the dermatologist of this concern. Because of lack of objective data regarding the malignant transformation of this diagnosis, the method of treatment is often based on the clinical appearance of the residual lesion or the lesion is rebiopsied to establish a more definitive diagnosis, costing patient and physician time and increasing health care costs. This study aims to provide objective data regarding (1) how often dermatologists are resampling these lesions and (2) how accurately an AKT diagnosis identifies patient risk for a more aggressive lesion, to establish whether there is a benefit in providing more tissue for the initial biopsy. We performed a retrospective study examining 274 biopsies with a diagnosis of AKT. We found only 27% had follow-up rebiopsy or excision. Of these 73 cases, 63% showed residual AK and 20% showed a more serious lesion, which warrants more aggressive treatment. Because the health care culture slowly shifts to metric-driven medicine and value-based payment, providing objective data for the progression of diagnosis, such as AKT, will be important (1) to aid the clinician in taking adequate tissue samples for diagnosis to make adequately informed management decisions, (2) to reduce the conversion of AK to squamous cell carcinoma, the resultant depth of squamous cell invasion, and the patient's risk of metastases to improve the patient's long-term outcomes, and (3) to decrease the overall cost of the patient's health care by improving the patient's long-term outcomes.

Mobile teledermatopathology: using a tablet PC as a novel and cost-efficient method to remotely diagnose dermatopathology cases.

: Dermatopathology has relatively few studies regarding teledermatopathology and none have addressed the use of new technologies, such as the tablet PC. We hypothesized that the combination of our existing dynamic nonrobotic system with a tablet PC could provide a novel and cost-efficient method to remotely diagnose dermatopathology cases. 93 cases diagnosed by conventional light microscopy at least 5 months earlier by the participating dermatopathologist were retrieved by an electronic pathology database search. A high-resolution video camera (Nikon DS-L2, version 4.4) mounted on a microscope was used to transmit digital video of a slide to an Apple iPAD2 (Apple Inc, Cupertino, CA) at the pathologist's remote location via live streaming at an interval time of 500 ms and a resolution of 1280/960 pixels. Concordance to the original diagnosis and the seconds elapsed to reaching the diagnosis were recorded. 24.7% (23/93) of cases were melanocytic, 70.9% (66/93) were nonmelanocytic, and 4.4% (4/93) were inflammatory. About 92.5% (86/93) of cases were diagnosed on immediate viewing (<5 seconds), with the average time to diagnosis at 40.2 seconds (range: 10-218 seconds). Of the cases diagnosed immediately, 98.8% (85/86) of the telediagnoses were concordant with the original. Telepathology performed via a tablet PC may serve as a reliable and rapid technique for the diagnosis of routine cases with some diagnostic caveats in mind. Our study established a novel and cost-efficient solution for those institutions that may not have the capital to purchase either a dynamic robotic system or a virtual slide system.

HDAC inhibition prevents transgene expression downregulation and loss-of-function in T-cell-receptor-transduced T cells.

T cells that are gene-modified with tumor-specific T cell receptors are a promising treatment for metastatic melanoma patients. In a clinical trial, we treated seven metastatic melanoma patients with autologous T cells transduced to express a tyrosinase-reactive T cell receptor (TCR) (TIL 1383I) and a truncated CD34 molecule as a selection marker. We followed transgene expression in the TCR-transduced T cells after infusion and observed that both lentiviral- and retroviral-transduced T cells lost transgene expression over time, so that by 4 weeks post-transfer, few T cells expressed either lentiviral or retroviral transgenes. Transgene expression was reactivated by stimulation with anti-CD3/anti-CD28 beads and cytokines. TCR-transduced T cell lentiviral and retroviral transgene expression was also downregulated in vitro when T cells were cultured without cytokines. Transduced T cells cultured with interleukin (IL)-15 maintained transgene expression. Culturing gene-modified T cells in the presence of histone deacetylase (HDAC) inhibitors maintained transgene expression and functional TCR-transduced T cell responses to tumor. These results implicate epigenetic processes in the loss of transgene expression in lentiviral- and retroviral-transduced T cells.

The functional role of Notch signaling in triple-negative breast cancer.

The term "triple-negative breast cancer" (TNBC) is a heterogeneous subtype of breast cancer. Unfortunately, due to the lack of expression of hormone receptors and human epidermal growth factor receptor-2, therefore the lack of US Food and Drug Administration-approved targeted therapies, TNBC has the worst prognosis of all subtypes of breast cancer. Notch signaling has emerged as a pro-oncogene in several human malignancies and has particularly been associated with the triple-negative subtype of breast cancer. This chapter explores the role of Notch signaling in triple negative and other subtypes of breast cancer, the relationship of Notch with other breast cancer biomarkers, prognostic indicators associated with Notch, and potential therapeutic strategies targeting Notch inhibition. Hopefully, better understanding of this signaling pathway in the future will lead to optimal molecular therapeutic treatments for TNBC patients, improving their quality of life and outcome.