Mark A. Cappel

New World and Old World Leishmania Infections: A Practical Review.

Leishmaniasis is a parasitic infection endemic to more than 90 countries worldwide. As travel to endemic areas increases, dermatologists need to keep this entity in the differential for any chronic skin lesion in persons who may have had a possible exposure for any duration. It can be difficult to diagnose because manifestations are varied and sometimes subclinical. This article discusses the current state of epidemiology, pathogenesis, clinical presentation, diagnosis, and treatment options. A special focus is placed on cutaneous manifestations and their treatment.

Lichenoid dermatitis in three patients with metastatic melanoma treated with anti-PD-1 therapy.

Joseph and colleagues describe the immunemediated rash, lichenoid dermatitis, in three patients treated with anti–PD-1 (MK-3475). These mild rashes are characterized by a marked T-cell infiltrate with ∼10% PD-1+ T cells. Therapies that activate the immune system through blocking the binding of programmed death ligand 1 (PD-L1) present on tumors and PD-1 (programmed death 1) present on activated immune cells are revolutionizing the care for patients with cancer. These therapies work by inhibiting negative regulators of the immune system, thereby decreasing a tumors ability to evade the immune system. The side effects of anti–PD-1/PD-L1 therapies are generally mild and as expected are related to autoimmune reactions. Two of the most common side effects of anti–PD-1/PD-L1 therapies are rash and pruritus occurring in approximately 20% of patients. Although the rash is generally recognized to be immune mediated, the exact mechanisms of the rash remain unclear. Herein, we report three cases of lichenoid dermatitis in three patients treated with MK-3475 (anti–PD-1) that were characterized with marked T-cell infiltrates with few PD-1–positive cells. The rashes in all three patients were relatively mild, allowing treatment to continue despite the rashes. Cancer Immunol Res; 3(1); 18–22. ©2014 AACR.

Tumor Cell Adhesion As a Risk Factor for Sentinel Lymph Node Metastasis in Primary Cutaneous Melanoma

PURPOSE Less than 20% of patients with melanoma who undergo sentinel lymph node (SLN) biopsy based on American Society of Clinical Oncology/Society of Surgical Oncology recommendations are SLN positive. We present a multi-institutional study to discover new molecular risk factors associated with SLN positivity in thin and intermediate-thickness melanoma. PATIENTS AND METHODS Gene clusters with functional roles in melanoma metastasis were discovered by next-generation sequencing and validated by quantitative polymerase chain reaction using a discovery set of 73 benign nevi, 76 primary cutaneous melanoma, and 11 in-transit melanoma metastases. We then used polymerase chain reaction to quantify gene expression in a model development cohort of 360 consecutive thin and intermediate-thickness melanomas and a validation cohort of 146 melanomas. Outcome of interest was SLN biopsy metastasis within 90 days of melanoma diagnosis. Logic and logistic regression analyses were used to develop a model for the likelihood of SLN metastasis from molecular, clinical, and histologic variables. RESULTS ITGB3, LAMB1, PLAT, and TP53 expression were associated with SLN metastasis. The predictive ability of a model that included these molecular variables in combination with clinicopathologic variables (patient age, Breslow depth, and tumor ulceration) was significantly greater than a model that only considered clinicopathologic variables and also performed well in the validation cohort (area under the curve, 0.93; 95% CI, 0.87 to 0.97; false-positive and false-negative rates of 22% and 0%, respectively, using a 10% cutoff for predicted SLN metastasis risk). CONCLUSION The addition of cell adhesion-linked gene expression variables to clinicopathologic variables improves the identification of patients with SLN metastases within 90 days of melanoma diagnosis.

Histiocytoid Sweet syndrome may indicate leukemia cutis: A novel application of fluorescence in situ hybridization

BACKGROUND In patients with malignancy-associated Sweet syndrome, a thorough evaluation for leukemia cutis should be considered. OBJECTIVE We sought to describe the clinicopathologic characteristics of histiocytoid Sweet syndrome. METHODS We retrospectively identified patients with histiocytoid Sweet syndrome at our institution from January 1992 through December 2010. We evaluated the underlying cutaneous infiltrate using immunohistochemistry and fluorescence in situ hybridization. RESULTS We re-evaluated all 22 patients with hematologic malignancy-associated Sweet syndrome. Six patients had a monocytoid infiltrate that was consistent with histiocytoid Sweet syndrome; subsequent evaluation of these patients demonstrated cytogenetic abnormalities on prior bone-marrow biopsy specimens. Fluorescence in situ hybridization analysis was feasible in cutaneous specimens from 5 of the 6 patients and demonstrated the same cytogenetic abnormalities that were identified on prior bone-marrow biopsy specimens in 4 patients. Therefore, these 4 patients may have had a form of leukemia cutis. LIMITATIONS This was a retrospective study. CONCLUSION For patients with histiocytoid Sweet syndrome, an underlying hematologic malignancy, and a monocytoid infiltrate on biopsy specimen, fluorescence in situ hybridization of the cutaneous infiltrate may be beneficial to identify cytogenetic abnormalities that may indicate leukemia cutis.

A clinical scoring system to identify patients with sebaceous neoplasms at risk for the Muir-Torre variant of Lynch syndrome

Purpose:The Muir–Torre syndrome variant of Lynch syndrome is characterized by the presence of sebaceous neoplasms (adenoma, epithelioma/sebaceoma, carcinoma) and Lynch syndrome–associated cancers (colon, endometrial, and others). Several clinical scoring systems have been developed to identify patients with colon cancer at high risk of Lynch syndrome. However, no such system has been described for patients presenting with sebaceous neoplasms.Methods:Based on logistic regression analysis, a scoring system was developed for patients with sebaceous neoplasm to identify those with the highest likelihood of having Muir–Torre syndrome. The final version of the scoring system included variables such as age at presentation of initial sebaceous neoplasm, total number of sebaceous neoplasms, personal history of a Lynch-related cancer, and family history of Lynch-related cancers.Results:Patients with a score of 3 or more were more likely to have Muir–Torre syndrome (28 of 29 patients), those with a score of 2 had intermediate likelihood (12 of 20 patients), and no patient with a score of 0 or 1 was diagnosed with Muir–Torre syndrome.Conclusion:The Mayo Muir–Torre syndrome risk scoring system appears to identify whether patients who present with sebaceous neoplasms are in need of further Lynch syndrome evaluation using easily ascertained clinical information. Abnormal mismatch repair gene immunohistochemistry of a sebaceous neoplasm is a poor predictor in regard to diagnosing Lynch syndrome.Genet Med 16 9, 711–716.

Comparison of virtual microscopy and glass slide microscopy among dermatology residents during a simulated in-training examination

Virtual microscopy is increasingly being used in dermatopathology educational settings.

Intralymphatic cutaneous anaplastic large cell lymphoma/lymphomatoid papulosis: expanding the spectrum of CD30-positive lymphoproliferative disorders.

Intravascular large B-cell lymphomas and EBV+ NK/T-cell lymphomas commonly follow an aggressive clinical course. We recently reported an entirely intravascular anaplastic large cell lymphoma (ALCL) in the skin with a surprisingly indolent clinical course; interestingly, this lymphoma involved the lymphatic rather than the blood vasculature. We hypothesized that intravascular skin-limited ALCL is distinct from aggressive systemic intravascular lymphomas in its intralymphatic localization and clinical course. We now describe 18 cases of cutaneous intravascular large cell lymphoproliferations from 4 institutions. All 12 intravascular large T-cell lesions were intralymphatic; the majority (9) were CD30+ T-cell lymphoproliferative disorders (TLPDs), 5 further classified as intravascular ALK− ALCL. One ALK+ ALCL and 2 benign microscopic intravascular T-cell proliferations were also intralymphatic. A single case of otherwise typical cutaneous follicle center lymphoma contained intralymphatic centroblasts. The clinical and pathologic characteristics of the CD30+ TLPDs were similar to those of their extravascular counterparts, including extralymphatic dermal involvement in a subset, DUSP22-IRF4 translocations in half of tested ALK− ALCLs, and associated mycosis fungoides in 1; most were skin-limited at baseline and remained so at relapse. All 5 cases of intravascular large B-cell lymphoma involved the blood vasculature and behaved in a clinically aggressive manner; the ALK+ ALCL, although intralymphatic, was systemic and clinically aggressive. We propose that cutaneous ALK− ALCL and related CD30+ ALK− TLPDs involving the lymphatics are part of an expanding spectrum of CD30+ TLPDs. The identification of intralymphatic as distinct from blood vascular localization may provide critical prognostic and therapeutic information.

Basosquamous carcinoma and metatypical basal cell carcinoma: a review of treatment with Mohs micrographic surgery.

Basosquamous carcinoma (BSC) and metatypical basal cell carcinoma (MBCC) are uncommon tumors poorly defined in the literature. Available studies suggest these tumors carry a greater risk of recurrence and metastases than basal cell carcinomas (BCCs) and, in some studies, squamous cell carcinomas. Formal treatment recommendations are not fully established.

Clinical features of shiitake dermatitis: a systematic review

Shiitake dermatitis is a rare cutaneous reaction to lentinan, a polysaccharide component in the cell walls of shiitake mushrooms (Lentinula edodes). Herein, we systematically review the case report and case series English‐language literature on shiitake dermatitis, which refers to a total of 50 patients (38 males, 12 females; mean age: 44.58 years). The majority of cases occurred after the consumption of raw mushrooms, whereas 22% of cases were caused by the eating of lightly or undercooked mushrooms. The most common clinical presentations, localized symptoms, and systemic findings include linear flagellated dermatitis (98%), pruritus (78%), and fever, diarrhea, and mucosal ulcers, respectively. The diagnosis of this entity continues to be based on clinical findings as laboratory abnormalities, and the findings of skin biopsies and patch/prick tests are nonspecific and inconsistent. The condition is self‐limiting, resolving in approximately 12.5 d without treatment. Based on the included case reports, it appears that medical treatment may slightly shorten the course of disease (to 9–11 d, varying by therapy) but should be considered on an individual patient basis. However, the treatment of symptoms, reassurance, and the avoidance of re‐exposure are sufficient treatment recommendations for this condition.

Treatment of in-transit and metastatic melanoma in two patients treated with ipilimumab and topical imiquimod.

Checkpoint blockade inhibitors have revolutionized the treatment of metastatic melanoma. Despite the success of these agents in improving the overall survival of patients with metastatic melanoma, not all patients achieve clinical benefit, leaving room for improvement. The presence of cutaneous metastases in patients with metastatic melanoma provides the unique opportunity to treat the cutaneous lesions with a local modality while simultaneously treating systemic disease with systemic therapy. Herein, we describe the treatment of two patients with both in-transit and metastatic melanoma with the combination of the topical toll-like receptor 7 agonist imiquimod with systemic ipilimumab. Both patients appeared to have progressed and developed new cutaneous and systemic metastases while on single agent ipilimumab only to respond when started on topical imiquimod. Both patients tolerated the combination of imiquimod and ipilimumab without serious adverse events, and both patients had excellent clinical responses. These cases provide a proof of principle of the possibility of the combination of toll-like receptor 7 agonists with immune checkpoint blockade inhibitors.