Faculty Bibliography

We present a 64-year-old man with a three-year history of pruritic, pink papules and nodules of the face who was found to have a clonal lymphoproliferative B-cell disease that was characterized by a clonal IGH rearrangement. Although morphologic features present in the biopsy specimen were consistent with a reactive process, additional clinicopathologic correlation (anatomic presentation of lesions on the face, the absence of t(14:18) translocation, and bcl-2 and MUM1 expression) reinforced suspicion of a cutaneous B-cell lymphoma. Systemic work-up with CT/PET and a bone marrow biopsy ultimately excluded systemic disease and primary cutaneous follicle-center lymphoma (PCFCL) was a strong diagnostic consideration. The patient was treated with systemic rituximab with a partial resolution of the facial lesions. The case demonstrates both clinical and pathologic challenges to the diagnosis of primary cutaneous B-cell lymphoma (PCBCL). Furthermore, despite a newly refined classification system, the case also specifically highlights the persistent requirement for flexible clinical reasoning and pathologic correlation. Such reasoning is necessary to generate individualized strategies for diagnosis and treatment when cutaneous B-cell lymphoma is suspected.

Palpable migratory arciform erythema is a T-cell pseudolymphoma with no well-established treatment. The disease is rarely reported in the literature, perhaps because it is difficult to diagnose. We present a case of a variant of PMAE in a 30-year-old healthy man with no history of medication use and erythematous to violaceous annular and arciform plaques on his face, scalp and trunk. This case is of particular significance because gene rearrangement studies and histopathologic findings are concerning for folliculotropic mycosis fungoides while the clinical course does not support this diagnosis. The authors' emphasize that clinical history is imperative for definitive diagnosis of palpable migratory arciform erythema as it can clinically and histopathologically resemble other cutaneous lymphocytic diseases

J Drugs Dermatol 2014;13(10):1288-1289.

Morphea and lichen sclerosus et atrophicus (LSA) have similar clinical presentations. Reports of patients with overlapping clinical and histopathologic features of both conditions have led some to speculate that they may represent different presentations along the same disease spectrum. It has been postulated that there is a common etiologic agent, which may involve autoimmunity, response to trauma, or infection. The link between Borrelia infection and both morphea and LSA has been widely studied but remains controversial. We present a case of a patient with lesions characterized by overlapping features of morphea and LSA with rapid decrease in joint mobility.

A 35-year-old man initially was referred for management of recalcitrant urticaria. Owing to his long history of arthritis and sensorineural hearing loss, genetic testing was performed. The test showed a D305N heterozygous mutation in the NLRP3 gene, which is consistent with the diagnosis of Muckle-Wells syndrome. We discussed the rationales behind the use of the interleukin-1 antagonist anakinra in this autoinflammatory disorder.

We present a case of chronic graft-versus-host disease in a 61-year-old woman with a history of B-cell chronic lymphocytic leukemia that was treated with an allogeneic bone marrow transplant from an unrelated donor. The patient initially presented with erythematous patches on the trunk and extremities that evolved into reticulated, hyperpigmented patches and lichenified plaques.

Notch signaling is essential for the development of T cell progenitors through the interaction of NOTCH1 receptor on their surface with the ligand, Delta-like 4 (DLL4), which is expressed by the thymic epithelial cells. Notch signaling is quickly shut down once the cells pass beta-selection, and CD4/CD8 double positive (DP) cells are unresponsive to Notch. Over the past two decades a number of papers reported that over-activation of Notch signaling causes T cell acute lymphoblastic leukemia (T-ALL), a cancer that prominently features circulating monoclonal CD4/CD8 double positive T cells in different mouse models. However, the possible outcomes of Notch over-activation at different stages of T cell development are unknown, and the fine timing of Notch signaling that results in T-ALL is poorly understood. Here we report, by using a murine model that ectopically expresses DLL4 on developing T cells, that the T-ALL onset is highly dependent on a sustained Notch activity throughout the DP stage, which induces additional mutations to further boost the signaling. In contrast, a shorter period of Notch activation that terminates at the DP stage causes a polyclonal, non-transmissible lymphoproliferative disorder that is also lethal. These observations resolved the discrepancy of previous papers on DLL4 driven hematological diseases in mice, and show the critical importance of the timing and duration of Notch activity.

Linear morphea of the forehead or en coup de sabre (ECDS) is an unusual variant of morphea. It typically occurs in children although cases of adult-onset ECDS exist as reported here. ECDS has a specific distribution on the frontal scalp and forehead and is usually unilateral. Sclerosis in ECDS lesions may invade deeply to involve underlying muscle and bone and may exist on the same clinicopathologic spectrum as Parry-Romberg syndrome. Extracutaneous involvement is frequent, with neurologic and ophthalmologic findings occurring most commonly. The etiology of ECDS is unclear but may be autoimmune in origin. The question of whether Borrelia infection also plays a role remains controversial. Current evidence supports first-line treatment with methotrexate and oral glucocorticoids followed by phototherapy and mycophenolate mofetil.

We report a 79-year-old man with a 15-year history of elongated, finger-like, erythematous patches that are symmetrically distributed on his flanks and of small, <5 cm, erythematous, slightly scaly, round-oval patches on the upper and lower extremities. The lesions were occasionally pruritic and waxed and waned over the years. His clinical and histopathologic data indicated small-plaque parapsoriasis, which is a benign entity that has been the center of controversy over the years, owing to its similarities to large-plaque parapsoriasis, which is on a spectrum with mycosis fungoides.

Poikilodermatous mycosis fungoides (MF) is a variant of MF, formerly referred to as poikiloderma vasculare atrophicans. The lesions are classically characterized by large plaques of hypopigmentation and hyperpigmentation with atrophy and telangiectases. The plaques may be asymptomatic or mildly pruritic and typically involve the major flexural areas and trunk. Poikilodermatous MF has an early stage (IA-IIA) at diagnosis and a male predominance. Poikilodermatous MF shows an atypical T-cell infiltrate in the papillary dermis with evidence of epidermotropism, epidermal atrophy, dilated blood vessels in the dermis, melanophages, and melanin incontinence. Recent studies suggest a predominance of a CD8+, CD4- immunophenotype. Treatment modalities are similar to classic MF with phototherapy being the most common first-line therapy. Poikilodermatous MF has an excellent prognosis.