Cutaneous Richter syndrome: Report of 3 cases from one institution

CLL/SLL with initial presentation as a longstanding cutaneous plaque: a rare case

While chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) is the most common leukemia in the western world, it uncommonly initially presents as a cutaneous lesion. When it does, it is often found incidentally in the context of another distinct lesion. We present a case of CLL/SLL that initially presented as a solitary nodular erythematous plaque on the left flank of a healthy 60-year-old man without lymphadenopathy or constitutional symptoms. The lesion had been present for many years, but had recently begun to grow and become pruritic and painful. Excisional biopsy revealed a large nodular aggregate of variably sized CD20(dim), CD5(+), CD23(+), BCL-2(+) atypical lymphocytes in the dermis without epidermotropism. The lymphocytes were negative for BCL-1/cyclinD1, BCL-6, and CD10, and no other background lesion was identified. This constellation of biopsy findings was consistent with CLL/SLL. This case emphasizes the potential for involvement by CLL/SLL in the cutaneous biopsies of otherwise asymptomatic patients.

Cutaneous Richter syndrome: a better place to transform?

The development of high-grade lymphoma in patients with chronic lymphocytic leukaemia is known as Richter syndrome (RS) and is associated with a grave prognosis, with a mean survival of 8 months despite treatment. Cutaneous RS has been described in a handful of cases and may be associated with a better outcome than the more common extracutaneous variants. We review the literature with particular emphasis on pathogenesis, treatment and survival of RS. We postulate that the absence of B symptoms and a normal lactate dehydrogenase level, presumably reflecting localized or limited disease, and a lower tumour burden, may explain the apparently better survival in some patients with cutaneous RS than with extracutaneous variants.

A unique case of concurrent chronic lymphocytic leukemia/small lymphocytic lymphoma and lymphomatoid papulosis in the same biopsy

Chronic lymphocytic leukemia (CLL/SLL) is the most common leukemia in the western world and its cutaneous dissemination a very uncommon phenomenon. Lymphomatoid papulosis (LyP) is a CD30+ lymphoproliferative disorder characterized by chronic, recurrent and self healing skin lesions. Up to 20% of patients with LyP have a coexistent lymphoma. While the association between the two entities has been reported, their coexistence has never been documented. We describe a 74-year-old man with known CLL and thrombocytopenia who presented with a 2 year history of recurrent nodules and plaques to both arms and legs that resolved within 4-6 weeks after administration of rituximab and bendamustin for his CLL treatment. His biopsies showed an atypical lymphoid infiltrate, composed of large and pleomorphic cells with a nodular and interstitial pattern in a background of eosinophils. Immunohistochemical staining revealed a pattern of two separate yet coexisting neoplastic processes; a large CD30 positive T-cell lymphoproliferative disorder, while the other one was diagnostic of a neoplastic B-cell process (leukemia cutis). A diagnosis of coexistent LyP and cutaneous involvement by CLL/SLL was rendered. The simultaneous presence of both disorders can be a pitfall in the differential diagnosis of large cell lymphomas, such as Richter's transformation of CLL/SLL.