Metabolic Lipids in Melanoma Enable Rapid Determination of Actionable BRAF-V600E Mutation with Picosecond Infrared Laser Mass Spectrometry in 10 s.

Rapid molecular profiling of biological tissues with picosecond infrared laser mass spectrometry (PIRL-MS) has enabled the detection of clinically important histologic types and molecular subtypes of human cancers in as little as 10 s of data collection and analysis time. Utilizing an engineered cell line model of actionable BRAF-V600E mutation, we observed statistically significant differences in 10 s PIRL-MS molecular profiles between BRAF-V600E and BRAF-wt cells. Multivariate statistical analyses revealed a list of mass-to-charge (m/z) values most significantly responsible for the identification of BRAF-V600E mutation status in this engineered cell line that provided a highly controlled testbed for this observation. These metabolites predicted BRAF-V600E expression in human melanoma cell lines with greater than 98% accuracy. Through chromatography and tandem mass spectrometry analysis of cell line extracts, a 30-member "metabolite array" was characterized for determination of BRAF-V600E expression levels in subcutaneous melanoma xenografts with an average sensitivity and specificity of 95.6% with 10 s PIRL-MS analysis. This proof-of-principle work warrants a future large-scale study to identify a metabolite array for 10 s determination of actionable BRAF-V600E mutation in human tissue to guide patient care.

Picosecond Infrared Laser Mass Spectrometry Identifies a Metabolite Array for 10 s Diagnosis of Select Skin Cancer Types: A Proof-of-Concept Feasibility Study.

Currently, a large number of skin biopsies are taken for each true skin cancer case detected, creating a need for a rapid, high sensitivity, and specificity skin cancer detection tool to reduce the number of unnecessary biopsies taken from benign tissue. Picosecond infrared laser mass spectrometry (PIRL-MS) using a hand-held sampling probe is reported to detect and classify melanoma, squamous cell carcinoma, and normal skin with average sensitivity and specificity values of 86-95% and 91-98%, respectively (at a 95% confidence level) solely requiring 10 s or less of total data collection and analysis time. Classifications are not adversely affected by specimen's quantity of melanin pigments and are mediated by a number of metabolic lipids, further identified herein as potential biomarkers for skin cancer-type differentiation, 19 of which were sufficient here (as a fully characterized metabolite array) to provide high specificity and sensitivity classification of skin cancer types. In situ detection was demonstrated in an intradermal melanoma mouse model wherein in vivo sampling did not cause significant discomfort. PIRL-MS sampling is further shown to be compatible with downstream gross histopathologic evaluations despite loss of tissue from the immediate laser sampling site(s) and can be configured using selective laser pulses to avoid thermal damage to normal skin. Therefore, PIRL-MS may be employed as a decision-support tool to reduce both the subjectivity of clinical diagnosis and the number of unnecessary biopsies currently required for skin cancer screening.

Mule/Huwe1/Arf-BP1 suppresses Ras-driven tumorigenesis by preventing c-Myc/Miz1-mediated down-regulation of p21 and p15.

Tumorigenesis results from dysregulation of oncogenes and tumor suppressors that influence cellular proliferation, differentiation, apoptosis, and/or senescence. Many gene products involved in these processes are substrates of the E3 ubiquitin ligase Mule/Huwe1/Arf-BP1 (Mule), but whether Mule acts as an oncogene or tumor suppressor in vivo remains controversial. We generated K14Cre;Mule(flox/flox(y)) (Mule kKO) mice and subjected them to DMBA/PMA-induced skin carcinogenesis, which depends on oncogenic Ras signaling. Mule deficiency resulted in increased penetrance, number, and severity of skin tumors, which could be reversed by concomitant genetic knockout of c-Myc but not by knockout of p53 or p19Arf. Notably, in the absence of Mule, c-Myc/Miz1 transcriptional complexes accumulated, and levels of p21CDKN1A (p21) and p15INK4B (p15) were down-regulated. In vitro, Mule-deficient primary keratinocytes exhibited increased proliferation that could be reversed by Miz1 knockdown. Transfer of Mule-deficient transformed cells to nude mice resulted in enhanced tumor growth that again could be abrogated by Miz1 knockdown. Our data demonstrate in vivo that Mule suppresses Ras-mediated tumorigenesis by preventing an accumulation of c-Myc/Miz1 complexes that mediates p21 and p15 down-regulation.

HPV-independent Vulvar Squamous Cell Carcinoma is Associated With Significantly Worse Prognosis Compared With HPV-associated Tumors.

Vulvar squamous cell carcinomas (VSCC) represent the most common carcinoma of the female external genitalia, with increasing incidence. Although high-risk human papillomavirus (HPV) infection has long been implicated in the majority of cervical and anal squamous cell carcinomas, there is uncertainty about its prevalence and prognostic impact in VSCC. In this study, we conducted a retrospective integrated morphologic and multimodal HPV analysis of a cohort of 114 VSCC cases treated at the Princess Margaret Cancer Centre/University Health Network, Toronto, Canada between 2000 and 2010. VSCC histology was reviewed. We analyzed the cohort for HPV using polymerase chain reaction based method, and tissue microarray DNA and RNA in situ hybridization (ISH), and p16 immunohistochemistry. Among the 114 cases (age 70±16 yr), 36.7% of cases were classified as having histomorphology of HPV infection. HPV was detected in 31.9% (polymerase chain reaction), 14.0% (DNA ISH), and 27.3% (RNA ISH) of cases. p16 immunohistochemistry was positive in 37.8% of cases. On univariate analysis, HPV morphology (P=0.009), p16+ (P=0.00013), DNA ISH+ (P=0.021), and RNA ISH+ (P=0.00061) were associated with better 5-yr progression-free survival. DNA ISH+ (P=0.049) was associated with better 5-yr overall survival. On multivariate analysis, HPV morphology (P=0.033), p16+ (P=0.01), and RNA ISH+ (P=0.035) were associated with better 5-yr progression-free survival. In conclusion, a subset of VSCC is associated with HPV, which correlates with better outcome. Relatively inexpensive tests such as histomorphologic evaluation, p16 immunohistochemistry, and HPV RNA ISH can be used to predict outcome in VSCC. Therefore, routine reporting of HPV status in VSCC is recommended.

Metastatic aneurysmal fibrous histiocytoma in a 20-year-old woman: A rare case report with review of the literature and discussion of its genomic features.

Aneurysmal fibrous histiocytoma is an uncommon variant of cutaneous fibrous histiocytomas with a local recurrence rate of 19%. We present a case of aneurysmal fibrous histiocytoma in a 20-year-old female with a regional lymph node metastasis and subsequent satellite nodule. The patient initially presented with a 1-month history of two palpable nodules in left lower anterior shoulder and left axilla. Needle core biopsies from both lesions revealed an atypical spindle cell neoplasm with a differential diagnosis of aneurysmal fibrous histiocytoma and angiomatoid fibrous histiocytoma. The axillary dissection confirmed a metastatic deposit in 1 out of 22 lymph nodes. At 6 months a satellite nodule arose between the resection scar and the axilla histopathologically demonstrating a cellular spindle cell nodule at the dermis subcutaneous junction with large, blood-filled pseudovascular spaces lined by histiocytes. The periphery of the lesion showed collagen trapping without a lymphoplasmacytic infiltrate. The lesional cells were diffusely positive for CD10 and focally for CD68 and Illumina RNA fusion panel sequencing was negative. Herein we present this case of metastatic aneurysmal fibrous histiocytoma with review of the literature and discussion of biology, cytogenetic alterations, and differential diagnosis.

Phase II clinical trial of adoptive cell therapy for patients with metastatic melanoma with autologous tumor-infiltrating lymphocytes and low-dose interleukin-2.

Adoptive cell therapy using autologous tumor-infiltrating lymphocytes (TIL) has shown significant clinical benefit, but is limited by toxicities due to a requirement for post-infusion interleukin-2 (IL-2), for which high dose is standard. To assess a modified TIL protocol using lower dose IL-2, we performed a single institution phase II protocol in unresectable, metastatic melanoma. The primary endpoint was response rate. Secondary endpoints were safety and assessment of immune correlates following TIL infusion. Twelve metastatic melanoma patients were treated with non-myeloablative lymphodepleting chemotherapy, TIL, and low-dose subcutaneous IL-2 (125,000 IU/kg/day, maximum 9-10 doses over 2 weeks). All but one patient had previously progressed after treatment with immune checkpoint inhibitors. No unexpected adverse events were observed, and patients received an average of 6.8 doses of IL-2. By RECIST v1.1, two patients experienced a partial response, one patient had an unconfirmed partial response, and six had stable disease. Biomarker assessment confirmed an increase in IL-15 levels following lymphodepleting chemotherapy as expected and a lack of peripheral regulatory T-cell expansion following protocol treatment. Interrogation of the TIL infusion product and monitoring of the peripheral blood following infusion suggested engraftment of TIL. In one responding patient, a population of T cells expressing a T-cell receptor Vß chain that was dominant in the infusion product was present at a high percentage in peripheral blood more than 2 years after TIL infusion. This study shows that this protocol of low-dose IL-2 following adoptive cell transfer of TIL is feasible and clinically active. (ClinicalTrials.gov identifier NCT01883323.).

Melanoma of the Vulva and Vagina: Surgical Management and Outcomes Based on a Clinicopathologic Reviewof 68 Cases.

OBJECTIVE: This study sought to evaluate the clinicopathologic features, surgical management, and survival of patients over 12 years at two academic centres. METHODS: Patients diagnosed with vulvar or vaginal melanoma between 2002 and 2014 were identified through pathology databases. Clinical and pathologic data were extracted from the medical records. The Kaplan-Meier method was used to calculate recurrence-free survival and overall survival (OS), and univariate analyses using a Cox proportional hazard model were used to detect covariates related to survival. RESULTS: Patients with vulvar melanoma were more likely to undergo surgical excision (84.0% vs. 55.6%, P = 0.0243) and were more likely to achieve negative margins (70.0% vs. 16.7%, P < 0.0001). Forty-eight percent of patients with vulvar melanoma had a lymph node evaluation; sentinel node biopsies were performed in 32%. Actuarial median OS for vulvar melanoma was 45 months compared with 10.48 months for vaginal melanoma. A subset of 10 patients with vulvar melanoma who survived longer than 60 months was identified. Eight significant predictors of OS were demonstrated for vulvar melanomas: clinical stage, maximum tumour size, tumour thickness, lymphovascular space invasion status, clinically enlarged lymph nodes, sentinel lymph nodes, lymph node status, and radiation treatment. Patients with positive or indeterminate margin status demonstrated a higher risk of recurrence than did patients with negative margins (hazard ratio 2.60; 95% CI 1.14-5.90). CONCLUSION: Surgical excision with adequate margins is the mainstay of primary management when feasible. Lymph node evaluation, including sentinel nodes, may be considered in selected patients. Vulvar and vaginal sites differ markedly with respect to pathology, initial management, and survival, and they should be evaluated separately.

Bullous leukemia cutis: a rare clinical subtype.

Leukemia cutis represents infiltration of the skin by malignant leukocytes and typically presents as firm, red-brown papules and nodules. The bullous clinical subtype is considered a rare entity and can be a diagnostic challenge. This case describes a patient with bullous leukemia cutis mimicking vesiculobullous skin disease.

Case Report of a 21-Year-Old Man With Epidermolysis Bullosa Acquisita.

Epidermolysis bullosa acquisita (EBA) is a rare acquired type of mechanobullous disease affecting the dermal-epidermal junction (DEJ) of trauma prone acral surfaces. It manifests as tense vesicles, bullae, and milia and typically heals as atrophic hypo- or hyperpigmented scars. Classic noninflammatory mechanobullous EBA typically presents at a mean age of 48 years. A 21-year-old man presented with a 2-year history of nonpainful papular-vesicular lesions on his hands, knees, and toes after minor trauma to these areas. Physical exam revealed postinflammatory hypopigmented scarring and milia to the bilateral dorsal hands and bilateral extensor elbows and knees, with tense blisters on the dorsal hand and patella regions. Direct immunofluorescence revealed strong linear IgG and IgM with weak focal positivity for IgA and C3 at the DEJ. Blood work revealed an increased diffuse gamma region of 71 g/L (6-13 g/L) on serum protein electrophoresis. Pathology showed a fibrotic underlying dermis, with subepidermal bullae and separation and no significant inflammation. The patient was started on colchicine. This case showcases an unusual early age of presentation for mechanobullous EBA and illustrates the importance of interpreting pathology in the context of clinical findings and maintaining a high index of suspicion for EBA in younger patients who present with classic findings. This case is unique as it is the first report of an association between EBA and polyclonal gammopathy and could be suggestive of chronic inflammation, which would fit with our patient's chronic history of EBA.

Primary Cutaneous Follicular Helper T-cell Lymphoma in a Patient With Neurofibromatosis Type 1: Case Report and Review of the Literature.

Patients with neurofibromatosis type 1 (NF-1) have a well-known predisposition for certain types of malignancies, including lymphoproliferative disorders. Cutaneous T-cell lymphoma (CTCL) has been reported in patients with NF-1, although it is considered a rare entity in this subset of patients. Cutaneous follicular helper T-cell lymphoma (CTFHCL) is a recently emerged rare subtype of CTCL with peculiar clinical and histopathological features and represents a diagnostic and therapeutic challenge. Only a few cases of CTFHCL have been reported in the literature. We report a case of CTFHCL in a patient with NF-1 and compare our findings with previously reported cases. We aim to raise awareness among pathologists regarding this rare subtype of CTCL and emphasize characteristic histological features of CTFHCL, which can be confused with B-cell lymphomas and lead to mismanagement.

Cutaneous Strongyloides Infection Postchemotherapy.

BACKGROUND AND OBJECTIVE: While clinical symptoms of strongyloidiasis are often nonspecific, larva currens (with erythematous, serpiginous, and pruritic papules and plaques) should prompt investigation including stool microscopy, serology, and skin biopsy of the lesion. Appropriate diagnosis and treatment with ivermectin is necessary, especially in the immunocompromised patient who is at increased risk for hyperinfection syndrome and disseminated disease. CONCLUSION: We present a 61-year-old immunocompromised man with presentation of larva currens of cutaneous strongyloides infection without symptoms of hyperinfection or disseminated disease.

Pathologic complete response to intralesional interleukin-2 therapy associated with improved survival in melanoma patients with in-transit disease.

PURPOSE: Melanoma patients with in-transit disease have a high mortality rate despite various treatment strategies. The aim of this study was to validate the role of intralesional interleukin (IL)-2, to understand its mechanism of action, and to better understand factors that may influence its response. METHODS: We retrospectively collected the clinicopathological data of 31 consecutive patients who presented to a tertiary care cancer center for treatment of in-transit melanoma with intralesional IL-2. Kaplan-Meier survival curves and multivariable Cox regression analysis were performed. Immunohistochemistry (IHC) was used to better understand the immune response to localized IL-2 therapy. Targeted next-generation sequencing was performed to genomically characterize the tumors. RESULTS: Ten patients (10/31, 32 %) achieved a pathologic complete response (pCR), 17/21 (55 %) had a partial response, and 4/21 (19 %) had progressive disease on treatment. pCR to IL-2 therapy was associated with overall survival (log-rank p = 0.004) and improved progression-free survival (PFS) [adjusted hazard ratio (HR) 0.11; 95 % CI 0.02-0.47; p = 0.003). A higher CD8+ T cell infiltrate was identified in in-transit lesions with a pCR compared with the other lesions (mean IHC score 3.78 vs. 2.61; p = 0.01). Patients with an elevated CD8+ infiltrate demonstrated an improved PFS (unadjusted HR 0.08; 95 % CI 0.01-0.52; p = 0.008). CONCLUSIONS: Thirty-two percent of patients achieved pCR with intralesional IL-2 therapy and had a significantly improved PFS compared with the rest of the cohort, which may be explained by a systemic CD8+ T-cell response.

Fibrolipomatous Hamartoma of the Nerve Arising in the Neck: A Case Report With Review of the Literature and Differential Diagnosis.

We report an unusual case of a fibrolipomatous hamartoma that arose in a nuchal nerve. Typically, fibrolipomatous hamartoma, otherwise known as a neural fibrolipoma or lipomatosis of nerve, arises in the median nerve, brachial plexus, cranial nerves, or plantar nerves. The differential diagnosis is broad and includes benign and malignant spindle cell lesions, such as spindle cell lipoma, perineurioma, and myxoid liposarcoma. We were able to identify the lesion based on the typical histology, including triphasic composition with spindle cell, neural, and adipocytic components and whorled architecture. Because of the atypical location in the neck, detailed immunohistochemical staining was performed. The lesional spindle cells were negative for SMA, CD10, CD68, EMA, S100, PGP9.5, CD34, CD56, and beta-catenin. Colloidal iron stain highlighted marked intralesional mucin deposition. This detailed immunohistochemical profile is a useful diagnostic aid and to our knowledge has not been previously described.

Malignant Melanoma of Vulva and Vagina: A Histomorphological Review and Mutation Analysis--A Single-Center Study.

OBJECTIVES: The aim of this work was to determine molecular characteristics and specifically, the frequency of BRAF, C-KIT, and NRAS mutations in vulvar and vaginal melanomas. METHODS: A retrospective review of all cases of vulvar and vaginal melanoma between 2002 and 2013 was performed. We reviewed the clinical and histological characteristics of all cases and performed genotyping studies on cases that had tissue available for the study, using next-generation sequencing. RESULTS: We identified 33 vulvar and 11 vaginal melanomas in women with mean ages 58 and 61 years, respectively. Next-generation sequencing analysis on 20 cases (15 vulvar and 5 vaginal) identified a BRAF mutation in 7.6%, C-KIT mutation in 27.6%, NRAS mutation in 27.6%, and TP53 mutation in 7.6% of the vulvar cases. We detected only a single TP53 mutation in the vaginal cases. We did not identify any statistically significant relationship between the mutation status and patients' outcome, depth of invasion, ulceration, stage at presentation, or lymph node metastasis. CONCLUSIONS: BRAF mutations are infrequent, whereas C-KIT and NRAS mutations are seen with higher frequency in vulvar melanomas than melanomas of other sites. These mutations can be considered as potential therapeutic targets in patients harboring them. Further studies are necessary to increase our understanding of mutational events occurring in melanoma of the lower female genital tract and their relationship with clinical parameters/outcome.

Neuroendocrine carcinoma of the skin--an updated review.

Primary neuroendocrine carcinoma of the skin, or Merkel Cell carcinoma (MCC), is a rare but aggressive tumor. Many recent advances on the morphology, immunophenotype, and pathogenesis have come to light in recent years. This review highlights the clinical features, varying histologies, histogenesis, advances in molecular pathology, prognosis, and current management of MCC. It also aims to aid in the differential diagnosis, with an emphasis on neuroendocrine tumors, and approach to the diagnosis of MCC with the use of immunohistochemistry and molecular studies.

Three Ds for diagnosing necrotizing fasciitis by front-line clinicians.

INTRODUCTION: Necrotizing fasciitis (NF) is a life-threatening infection and a surgical emergency. Not all clinicians have the experience or resources to detect NF in its early stages. OBJECTIVE: To develop a diagnostic algorithm for primary care and emergency physicians to identify patients with possible NF, including an initial approach to triaging such individuals. METHODS: Medline was searched to identify studies of validated algorithms for NF diagnosis and/or cohort or case series providing clinical and diagnostic features of NF. Candidate algorithms were validated via application to 3 published cases of initially misdiagnosed NF. We retrospectively reviewed NF cases between 2011 and 2022 at our center to validate our algorithm. RESULTS: The search yielded 540 articles; 109 were included following a review of abstracts. No published validated diagnostic algorithm was identified. Using the reported clinical and diagnostic features of NF, we generated an algorithm of the "3Ds" of NF: Disproportionate pain, Dermatological findings, and Disorganized physiology. A larger number of Ds indicated a greater level of suspicion for NF and prioritization for urgent surgical consultation. In 3 published cases of missed NF, the 3Ds algorithm successfully identified all as having possible NF. On reviewing our cases, we identified 56 patients with NF during an 11 year period. 66% of whom had the 3Ds at their initial presentation. DISCUSSION: The 3Ds algorithm, a simple and easy-to-remember tool can be easily applied in a primary or emergency care setting, and may improve the early diagnosis of NF. Retrospective analysis of NF cases allows for validation of this algorithm. However, this algorithm requires prospective validation.

Immunohistochemical Analysis of Lymphocyte Populations in Acute Skin Rejection: The University Health Network Addition to the Banff Classification.

Acute rejection in vascularized composite allotransplantation has been identified using the Banff 2007 working classification. We propose an addition to this classification based on histological and immunological assessment within the skin and subcutaneous tissue. Methods: Biopsies from vascularized composite transplant patients were obtained at scheduled visits and whenever skin changes occurred. Histology and immunohistochemistry were performed on all samples, looking at infiltrating cells. Results: Observations were made specifically related to each component of the skin, including the epidermis, dermis, vessels, and subcutaneous tissue. Our findings led to the establishment of the University Health Network addition of skin rejection. Conclusions: The high rate of rejection where the skin is involved requires novel techniques for early detection. The University Health Network skin rejection addition can serve as an adjunct to the Banff classification.

Linear arrangement of neutrophils along the Basal layer in bullous pemphigoid: a unique histological finding.

Bullous pemphigoid is an inflammatory autoimmune subepidermal bullous disease with distinct immunohistological features. We report an unusual case of a 59-year-old woman with a bullous eruption whose lesional skin biopsy showed a subepidermal blister with a linear arrangement of neutrophils, mimicking linear IgA bullous dermatosis. However, direct immunofluorescence studies demonstrated IgG and C3 linear deposition along the basement membrane zone, compatible with bullous pemphigoid. We suggest that bullous pemphigoid should therefore be considered in the differential diagnosis of neutrophil-rich subepidermal bullous diseases along with dermatitis herpetiformis and linear IgA.

Diagnosis of the origin of an epibulbar melanocytic tumor with molecular genomics.

BACKGROUND: Uveal melanoma (UM) and conjunctival melanoma (CM) are distinct entities with different etiologies and genetic background. We present a case of an atypical subconjunctival melanoma arising from a blue nevus. PATIENTS AND METHODS: A 61-year-old female presented with a partially melanocytic epibulbar mass with surrounding episcleral pigmented spots. The lesion was detached from the overlying conjunctiva without an intraocular component. Excisional biopsy revealed a predominantly epithelioid melanoma, that was suggested to be metastasic, although there was no evidence of a primary melanoma elsewhere. RESULTS: Molecular analysis identified GNAQ and BAP1 pathogenic variants, which strongly suggested the diagnosis as a primary epibulbar melanoma arising from episcleral blue nevus. CONCLUSION: This case demonstrates the value of tumor molecular analysis using Next Generation Sequencing (NGS) for differentiating the origin of an unusually located ocular melanoma.