Faculty Bibliography

We present a 56-year-old man with a two-year history of erythematous nodules and plaques on the forehead, frontal aspect of the scalp, and left side of the neck. Histopathologic findings are compatible with a diagnosis of diffuse large B-cell lymphoma (DLBCL). We present a brief review of primary cutaneous DLBCLs and address the putative association between DLBCLs and hepatitis C virus infection.

Minocycline has been used in the treatment of leprosy since the demonstration of its efficacy in inhibiting Mycobacterium leprae growth in 1987. Hyperpigmentation, a well-documented adverse effect, classically shows 3 clinical and histological patterns: type I consists of blue-black pigmentation in areas of current or previous inflammation, type II consists of blue-gray pigmentation of normal skin, often seen on the legs, and type III consists of diffuse muddy-brown pigmentation accentuated on sun-exposed sites. Whereas type I hyperpigmentation stains positively for hemosiderin and type III hyperpigmentation stains positively for melanin, type II hyperpigmentation stains positively for both. We describe 2 patients with leprosy on minocycline therapy who developed multiple patches of blue-gray pigmentation within preexisting leprosy lesions. Biopsies from both patients demonstrated deposition of brownish-black pigment granules within the cytoplasm of foamy histiocytes that was highlighted by both Perls and Fontana-Masson stains. Given the clinical and histological findings in our patients, it is as yet unclear whether this coexistent type I clinical pattern and type II histopathologic pattern of pigmentation is unique to multibacillary leprosy. These findings provide support for the existence of additional subtypes of minocycline-induced hyperpigmentation that do not adhere to the classic 3-type model described.

BACKGROUND: The longstanding concept of a Th1-Th2 dichotomy in leprosy, with Th1-predominant tuberculoid leprosy and Th2-predominant lepromatous leprosy (LL), has recently been challenged, and Cbl-b overexpression may emerge as an important factor in anergy and progression of LL. Moreover, Th17 and Th22 subsets have been identified as Th1-Th2 modulators in inflammatory skin diseases, most notably psoriasis, but their roles in leprosy have not yet been elucidated. The occurrence of pseudoepitheliomatous hyperplasia (PEH) with transepidermal elimination of mycobacteria in LL patients, which could theoretically be a portal for contact transmission, thus raises important immunological questions: Do Th17 and/or Th22 subsets mediate epidermal proliferation akin to Th1-driven psoriasis in supposedly Th2-predominant LL disease, and is the Th1-Th2 immunostat set systemically or locally? Furthermore, which microRNAs (miRs), signal transducers, and activators of transcription (STAT) proteins regulate this transition in leprosy, if any, and does differential Cb1-b expression play a role? OBSERVATION: A 71-year-old man presented with an infiltrative dermopathy characteristic of LL, as well as several hyperkeratotic plaques. Microscopic examination of the hyperkeratotic lesions demonstrated PEH with loss of the grenz zone and transepidermal elimination of acid-fast bacilli, whereas classic histopathologic features of LL were present at other sites. HYPOTHESES: We hypothesize that: Th17 and Th22 T-cell subsets act locally to induce T-cell plasticity in LL lesions, manifesting PEH; miR-181a is normal or increased in LL lesions with PEH compared to its expressional loss in classic LL lesions; miR-21 and STAT3 are increased in LL lesions with PEH, given their association with epithelial hyperproliferation; and Cbl-b is diminished in LL lesions with PEH compared to classic LL lesions. CONCLUSION: By understanding the factors that regulate T-cell and cytokine responses in leprosy, it should be possible to recognize these dynamic immunologic processes clinically and histopathologically and devise specific immunologic interventions.

The ideal dermal filler should offer long-lasting aesthetic improvement with a minimal side-effect profile. It should be biocompatible and stable within the injection site, with the risk of only transient undesirable effects from injection alone. However, all dermal fillers can induce serious and potentially long-lasting adverse effects. In Part II of this paper, we review the most common adverse effects related to dermal filler use.

Demonstration of T-cell receptor gene monoclonality often plays an important role in the diagnosis of T-cell lymphoma. When a test to detect monoclonality is performed on whole tissue sections, the presence of a reactive lymphocyte population may reduce sensitivity. This may be especially true for early or borderline cases of lymphoma. Microdissection techniques may be utilized to more readily identify a clonal population of lymphocytes. Subcutaneous panniculitis-like T-cell lymphoma represents a cutaneous lymphoid neoplasm whose clinical course may vary from an indolent, waxing and waning course to an aggressive course resulting in death. We report the first case of a microdissection technique used to facilitate diagnosing a case of subcutaneous panniculitis-like T-cell lympoma.

We report two unique cases of dermatofibrosarcoma protuberans (DFSP) that included a pseudocystic component. Molecular analysis of one of the cases showed a characteristic COL1A1-PDGFB rearrangement in both the main tumor and also in the cells lining the pseudocystic portion of the tumor, confirming the diagnosis and indicating that the lining represented a component of the proliferation. It is important to raise awareness of this rare variant within the varied spectrum of DFSP. Shvartsbeyn M, Lazar AJF, Lopez-Terrada D, Meehan SA. Pseudocystic dermatofibrosarcoma protuberans: report of two cases and demonstration of COL1A1-PDGFB rearrangement.

OBJECTIVE: Membrane endothelial protein C receptor (mEPCR) is highly expressed in peritubular capillaries of kidneys from patients with active and poorly responsive lupus nephritis (LN). We investigated the hypothesis that changes in the microvasculature are widespread with extension to the dermal vasculature. METHODS: Skin biopsies from uninvolved skin (buttocks) were performed in 27 patients with LN and 5 healthy controls. Sections were stained with specific antibodies reactive with mEPCR, adiponectin, intercellular adhesion molecule-1 (ICAM-1), and CD31; then assessed by enumeration of stained blood vessels (percentage positive blood vessels) blinded to knowledge of clinical information. RESULTS: There was a significant increase in the prevalence of blood vessels that stained for mEPCR and ICAM-1 in patients compared to controls [94% vs 59% (p = 0.045) and 81% vs 67% (p = 0.037), respectively]. Adiponectin staining and CD31 staining were similar between the groups (45% vs 43% and 98% vs 92%). Dermal staining for mEPCR was greater in patients with proliferative glomerulonephritis than in those with membranous disease (96% vs 60%; p = 0.029). A composite of poor prognostic renal markers and death was significantly associated with greater expression of mEPCR staining. CONCLUSION: These data are consistent with the notion that in patients with LN, activation of the microvasculature extends beyond the clinically targeted organ. The insidious expression of this widespread vasculopathy may be a contributor to longterm comorbidities.

Amelanotic melanoma can have a varied appearance both clinically and microscopically. Here, we present our experiences with 75 cases of amelanotic melanoma defined clinically as a non-pigmented lesion and histopathologically as a tumor lacking significant melanization. We evaluated microscopic features such as morphology, mitotic count, nuclear atypia and presence of solar elastosis. Our amelanotic melanomas exhibited the following morphology: epitheloid (72%), spindled (18.7%) or desmoplastic (5.3%). In addition, we obtained patient information and clinical presentations on most of the cases (74/75; 98.7%) and follow-up data on 40% (30/75) of the cases. The majority of amelanotic melanomas in men were found on the trunk (13/45; 29%), head and neck (12/45; 26.7%), and lower limb (13/45; 29%) and in women were found on the lower limb (12/30; 40%), upper limb (10/30; 33.3%) and head and neck (6/30; 20%). In addition, we found that an increase in mitotic index correlated with worse survival (p < 0.026), whereas there were no differences in survival for other pathological features, such as nuclear atypia or solar elastosis. Furthermore, in cases with available tissue, all amelanotic melanoma expressed microphthalmia-associated transcription factor and tyrosinase, suggesting that the tumor cells retained melanocytic lineage and an enzyme in melanin formation, respectively. As the occurrence of amelanotic melanoma and the expression melanoma markers were similar to pigmented melanoma, we favor that amelanotic melanoma represents a subtype of melanoma rather than poorly differentiated or de-differentiated melanoma. Cheung WL, Patel RR, Leonard A, Firoz B, Meehan SA. Amelanotic melanoma: a detailed morphologic analysis with clinicopathologic correlation of 75 cases

A 15-year-old boy with a diagnosis of generalized multiple glomangiomas was referred for evaluation and treatment of enlarging and increasingly painful lesions on his right ankle. The patient underwent a series of two treatments with long-pulsed KTP 1064 nm laser that resulted in substantial improvement in appearance and decreased pain. Generalized glomuvenous malformations, or multiple glomangiomas, are the less common presentation of proliferation of glomus cells and may have extracutaneous involvement. Whereas surgical management is often employed and definitive for solitary lesions, interventions such as laser therapy, may be beneficial for improvement of functional impairment and cosmesis as was observed in our patient.

The presence of lupus erythematosus with morphea in the same patient has rarely been reported. In this case, we describe a woman with the overlap of discoid lupus erythematosus with superficial morphea, diagnoses that are supported by histopathologic features and laboratory studies.