Shamir Geller

Dermoscopy and the diagnosis of primary cutaneous B‐cell lymphoma

Primary cutaneous B‐cell lymphomas (PCBCLs) are frequently misdiagnosed, and a biopsy is needed to attain the correct diagnosis.

Malignancy Risk and Recurrence with Psoriasis and its Treatments: A Concise Update

Psoriasis is a common inflammatory cutaneous disease that affects approximately 120 million people worldwide. Systemic treatments have significantly improved disease burden, but concerns persist regarding their association with increased risk of malignancy. Patients with psoriasis have a slightly elevated baseline risk of lymphoproliferative diseases. Studies on methotrexate and cyclosporine, as well as older biological agents such as tumor necrosis factor inhibitors, have found no increased risk of non-cutaneous solid tumors; however, positive associations between cutaneous squamous cell carcinomas and certain therapies have been found. There is conflicting evidence regarding the risk of lymphoma and melanoma. Further studies are needed to determine the long-term safety of newer psoriasis treatments (interleukin [IL]-12/23, IL-17, Janus kinase 1/3, and phosphodiesterase-4 inhibitors), specifically their safety in patients with a history of cancer. This review summarizes the most recent studies on malignancy risk from psoriasis, and its treatments in patients and cancer survivors, with the highest available level of evidence.

ALK-positive primary cutaneous anaplastic large cell lymphoma: a case report and review of the literature

Anaplastic large cell lymphoma (ALCL) limited to the skin is a distinct disease that is designated primary cutaneous ALCL (pcALCL). It has an indolent course with a significantly better prognosis compared to systemic ALCL (sALCL). Anaplastic lymphoma kinase (ALK) expression in lesions of cutaneous ALCL is classically considered to be a marker for skin involvement by sALCL. However, recent reports of patients with ALK‐positive pcALCL challenge this concept and raise prognostic and therapeutic dilemmas. Herein, we report a case of ALK‐positive pcALCL in a 45‐year‐old woman who was treated with local radiotherapy. We review previously reported cases in the literature to better characterize this rare variant. Overall, the rates of cutaneous recurrence, systemic dissemination, and disease‐related mortality in ALK‐positive pcALCL do not differ from those previously reported in pcALCL. ALK‐positive pcALCL is diagnosed at younger age and has a better disease course in children compared to adults with lower incidences of skin recurrence and progression to systemic disease. We conclude that ALK‐positivity in cutaneous ALCL does not necessarily imply systemic disease. ALK‐positive pcALCL has an excellent prognosis and should be treated by excision and/or radiotherapy. However, patients must remain under close long‐term follow‐up as recurrence and progression to systemic disease may occur.

Dermoscopic assessment of vascular structures in solitary small pink lesions—differentiating between good and evil

The diagnosis of a single small pink papule poses a real challenge to the clinician, as the differential diagnosis of such lesions includes benign entities such as a neurofibroma or hemangioma, as well as aggressive and potentially fatal skin malignancies such as amelanotic melanoma or Merkel cell carcinoma (MCC). The absence of a benign vascular pattern and the presence of atypical vascular features under dermoscopy direct the clinician to proceed to histologic evaluation in order to rule out a malignant process in such lesions. The diagnosis of MCC is particularly problematic, given that this tumor usually lacks specific clinical diagnostic features. Low clinical suspicion for MCC may result in delayed diagnosis and poor outcomes. The dermoscopic features of MCC are also non-specific, most commonly including milky-red areas and linear irregular vessels. We report a patient who presented with two discrete pink papules on different digits that appeared three years apart. Dermoscopy helped to diagnose a harmless hemangioma in the first lesion, and a MCC in the latter. The malignant tumor was diagnosed and excised expeditiously, with no evidence of metastatic spread.

NK/T-cell lymphoma, nasal type, γδ T-cell lymphoma, and CD8-positive epidermotropic T-cell lymphoma—clinical and histopathologic features, differential diagnosis, and treatment

The histopathological diagnosis of dermal-based lymphoid infiltrates and proliferations is often challenging due to the vast list of biologically diverse entities that archetypally or occasionally center in the mid-dermis, especially because significant overlap exists in their clinical, histopathologic, and immunophenotypic features. The differential diagnosis includes reactive infiltrates in common and rare inflammatory dermatoses, benign conditions that may mimic lymphoid neoplasms (pseudolymphomas), and true clonal proliferations arising either primarily in the skin or rarely in extracutaneous tissues with secondary cutaneous dissemination. While numerous histopathological and immunophenotypic features have been reported to support a definitive diagnosis, no single ancillary test is sufficient for their distinction. Therefore, in this review we advocate a stepped histopathological approach for dermalbased lymphoid infiltrations, employing as key elements the general lymphocytic composition (relative B- versus T-cell ratio), coupled with the predominant cytomorphology (cell size) present. Following this strategy, the relative incidence of cutaneous involvement by each disease should always be considered, as well as the notion that a definitive diagnosis must be founded on a multiparameter approach integrating all clinical, histopathologic, immunophenotypic, and-in selected cases-molecular features.

Treatment of Rosai-Dorfman Disease with oral Bexarotene: a case series

Abstract Background: Rosai–Dorfman disease (RDD) is a rare histiocytic proliferative disorder of unknown etiology. The skin is the most frequent extranodal site of RDD involvement and may be the only organ involved. While RDD is an indolent self-limited disease, treatment is needed in patients with extensive, persistent or progressive disease, or if cosmetic disfigurement or physical impairment significantly affects the patient. There is no specific treatment for RDD, and multiple therapeutic approaches have been described with variable success rates. Ojective: To demonstrate the clinical efficacy of oral bexarotene for RDD. Materials and methods: Descriptive retrospective case series of three patients with RDD receiving oral bexarotene. Results: Two patients had excellent response and regression of their skin lesions was achieved with long-term therapy. In the other patient, pruritus was promptly controlled while the lesions did not seem to regress and treatment was discontinued after five months. Conclusions: Our case series is the first report in the literature of the use of oral bexarotene as an effective and safe treatment for RDD.

Diffuse eruptive ulcerated plaques

A woman in her 90s presented to our clinic with pruritic widespread ulcerated papules and plaques that had rapidly developed within the previous 10 days. A 3-year history of a pruritic eczematous rash was reported. The patient complained of fatigue and a 20-pound weight loss within the past year. No fevers, chills, or night sweats were noted. Her medical history was significant for asthma and chronic back pain. Medications included ventolin and lorazepam. She had taken no new medication prior to the onset of rash. Physical examination revealed numerous erythematous papules and plaques with central necrosis on her neck, back, breasts, arms, abdomen, and thighs (Fig. 1). No patches or tumors were seen. No involvement of the oral mucosa was noticed. Palpation revealed no evidence of adenopathy. Two punch biopsies were performed on the patient’s upper back skin.

T-cell receptor-δ expression and γδ+ T-cell infiltrates in primary cutaneous γδ T-cell lymphoma and other cutaneous T-cell lymphoproliferative disorders

The diagnosis of cutaneous γδ T‐cell lymphoma (GDTCL) requires the identification of γδ chains of the T‐cell receptor (TCR). Our aim in this study was, by using a new monoclonal antibody (mAb) against TCRδ, to evaluate TCRδ expression in formalin‐fixed paraffin‐embedded (FFPE) skin tissue from TCRγ+ cutaneous T‐cell lymphoma (CTCL), and to assess TCRδ expression within a spectrum of other cutaneous lymphoproliferative disorders (CLPDs).

Solitary orange papule on the back of a middle-aged man

A 51-year-old man with a history of recurrent primary cutaneous marginal zone lymphoma involving his back returned for a follow-up visit at our cutaneous lymphoma clinic. He complained of a several-month history of a new asymptomatic papule on the mid-thoracic back. He denied fevers, chills, night sweats or fatigue. Clinical examination identified a 3 to 4 mm red to orange-colored papule on the middle back (Figure 1A). Dermoscopic examination of the lesion revealed an erythematous border encircling an orange-yellow area with white linear streaks and few dotted vessels (Figure 1B). A biopsy and histopathological examination performed to exclude recurrence of skin lymphoma demonstrated a nodular dermal infiltrate of histiocytes with vacuolated foamy xanthomatous cytoplasm and Touton-type multinucleated giant cells (Figure 2). The histiocytes stained positively for CD68 and were negative for Sox10.

Acneiform follicular mucinosis: an indolent follicular mucinosis variant unrelated to mycosis fungoides?

Follicular mucinosis (FM) can present as an acneiform eruption, and is usually a benign variant of primary FM unrelated to cutaneous T‐cell lymphoma (CTCL). We report two cases of women in their twenties who presented with an acneiform rash on the face, arms and back. In both cases, pathological evaluation of the facial papules revealed predominantly mucinous degeneration of the follicular epithelium, with insufficient lymphocytic infiltration or atypia to diagnose mycosis fungoides. These cases are similar to previous reports of acneiform FM. As none of the reported cases progressed to CTCL, we consider that overdiagnosis and overtreatment should be avoided in acneiform FM, but recommend long‐term follow‐up.