Cutaneous B‐cell lymphomas: 2016 update on diagnosis, risk‐stratification, and management

Abstract

Disease overviewApproximately one‐fourth of cutaneous lymphomas are B‐cell derived and are generally classified into three distinct subgroups: primary cutaneous follicle center lymphoma (PCFCL), primary cutaneous marginal zone lymphoma (PCMZL), and primary cutaneous diffuse large B‐cell lymphoma, leg type (PCDLBCL, LT).DiagnosisDiagnosis and disease classification is based on histologic review and immunohistochemical staining of an appropriate skin biopsy. Pathologic review and an appropriate staging evaluation are necessary to distinguish primary cutaneous B‐cell lymphomas from systemic B‐cell lymphomas with secondary skin involvement.Risk‐stratificationDisease histology remains the most important prognostic determinant. Both PCFCL and PCMZL are indolent lymphomas that infrequently disseminate to extracutaneous sites and are associated with 5‐year survival rates that exceed 95%. In contrast, PCDLBCL, LT is an aggressive lymphoma with an inferior prognosis.Risk‐adapted therapyPCFCL and PCMZL patients with solitary or relatively few skin lesions may be affectively managed with local radiation therapy. While single‐agent rituximab may be employed for patients with more widespread skin involvement, multiagent chemotherapy is rarely appropriate. In contrast, management of patients with PCDLBCL, LT is comparable to the management of patients with systemic DLBCL. Am. J. Hematol. 91:1052–1055, 2016. © 2016 Wiley Periodicals, Inc.

Extranodal Diffuse Large B Cell Lymphoma: Molecular Features, Prognosis, and Risk of Central Nervous System Recurrence

“…Unlike the indolent cutaneous MZL and follicle center lymphomas, primary cutaneous DLBCL, leg-type (PCDLBCL-LT) is aggressive, although rituximab has significantly improved survival outcomes [114, 115]. It classically, though not exclusively, presents as rapidly growing tumors on the legs of women over age 60 [1].…”

Cytologic perspectives on neoteric B‐cell lymphoproliferative disorders

“…1 Very little has been written about this disease entity from the cytology perspective since that time. [46][47][48] Histologic descriptions of primary cutaneous DLBCL, leg type describe diffuse, monotonous sheets of large B-cells within the dermis that are separated from the epidermis by a grenz zone. 2 These lymphoid neoplasms are uncommon, and most cases occur in elderly women who present with nodular erythematous skin lesions on the lower legs.…”

“…This disease is often rapidly progressive, and extracutaneous dissemination is common. [46][47][48] Histologic descriptions of primary cutaneous DLBCL, leg type describe diffuse, monotonous sheets of large B-cells within the dermis that are separated from the epidermis by a grenz zone. The lesional cells typically contain nuclei that are more than twice the size of normal lymphocytes, and some authors have used the descriptor of a "round cell" morphology.…”

“…These neoplasms are typically also positive for BCL2, MUM-1, and FOXP1, but generally lack CD10 expression ( Figure 6). 1,[46][47][48][49][50] which is thought to be due to immunoscenscence and occurs in the absence of a prior lymphoma. 1 In the new 2016 WHO classification, this entity changes to simply EBV-positive DLBCL, NOS.…”

Cancer stem cell–still an enigma in CTCL?

“…The genetic landscape of these cell subsets will facilitate future research to define the cell of origin of CTCL with significant impact on classification, risk stratification and treatment of these diseases (8).…”