title: Atypical clinicopathologic presentation of primary cutaneous diffuse large B-cell lymphoma, leg type.
abstract: BACKGROUND
  Primary cutaneous diffuse large B-cell lymphoma, leg type (cDLBCL-LT) is a well-defined entity of cutaneous B-cell lymphoma affecting predominantly elderly patients, mostly women. The typical clinical presentation is characterized by solitary or multiple, rapidly growing plaques or tumors on 1 leg (rarely both legs).
  
  
  OBJECTIVE
  We sought to describe a new clinical variant of cDLBCL-LT that deviates from the conventional one.
  
  
  METHODS
  Clinical, histopathologic, phenotypical, and molecular features of 3 cases of cDLBCL-LT presenting with patches or thin plaques were reviewed (all were women, aged 60, 62, and 87 years; lesions were located on the leg in all patients).
  
  
  RESULTS
  These patients presented with patches or thin plaques that represented the first manifestation of cDLBCL-LT. All 3 patients reported a history of long-standing lesions (present for 6, 9, and 18 months, respectively). Histology revealed moderately dense, perivascular infiltrates of small lymphocytes admixed with variable numbers of large cells that were CD20(+), Bcl-2(+), and MUM-1(+).
  
  
  CONCLUSIONS
  There were only a small number of cases.
  
  
  CONCLUSIONS
  We reported an unusual clinical presentation of cDLBCL-LT that deviates from the conventional one and that represents a formidable diagnostic challenge. Biopsy specimens of unusual patches/thin plaques or annular lesions should be obtained from the legs of adult patients if the lesions do not respond to conventional treatment.
authors.affiliation: Dermatopathology Research Unit, Department of Dermatology, Medical University of Graz, Graz, Austria.
authors.forename: Cesare
authors.initials: C
authors.lastname: Massone
authors.affiliation: Dermatopathology Research Unit, Department of Dermatology, Medical University of Graz, Graz, Austria.
authors.forename: Regina
authors.initials: R
authors.lastname: Fink-Puches
authors.affiliation: Dermatopathology Research Unit, Department of Dermatology, Medical University of Graz, Graz, Austria.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Wolf
authors.affiliation: Dermatopathology Research Unit, Department of Dermatology, Medical University of Graz, Graz, Austria.
authors.forename: Iris
authors.initials: I
authors.lastname: Zalaudek
authors.affiliation: Dermatopathology Research Unit, Department of Dermatology, Medical University of Graz, Graz, Austria. Electronic address: lorenzo.cerroni@medunigraz.at.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Cerroni
mesh_terms: D000369:Aged, 80 and over; D001707:Biopsy, Needle; D059248:Chemoradiotherapy / Q000379:methods; D003131:Combined Modality Therapy; D005260:Female; D005500:Follow-Up Studies; D018380:Hematopoietic Stem Cell Transplantation / Q000379:methods; D006801:Humans; D007150:Immunohistochemistry; D007866:Leg; D016403:Lymphoma, Large B-Cell, Diffuse / Q000175:diagnosis / Q000401:mortality / Q000473:pathology* / Q000628:therapy*; D016410:Lymphoma, T-Cell, Cutaneous / Q000175:diagnosis / Q000401:mortality / Q000473:pathology* / Q000628:therapy*; D008875:Middle Aged; D018570:Risk Assessment; D012494:Sampling Studies; D012878:Skin Neoplasms / Q000401:mortality / Q000473:pathology* / Q000628:therapy*; D015996:Survival Rate; D014057:Tomography, X-Ray Computed / Q000379:methods; D016896:Treatment Outcome
keywords: annular erythema; clinical presentation; cutaneous B-cell lymphoma; leg type; primary cutaneous diffuse large B-cell lymphoma