title: [T-cell prolymphocytic leukemia: potential diagnostic pitfalls].
abstract: BACKGROUND
  Sezary syndrome (SS) presents clinically as erythroderma, which may be pigmented, and pruritic, associated with peripheral lymphadenopathies. Erythroderma may also occur in a broad range of reactive and malignant conditions including T-cell prolymphocytic leukemia (T-PLL). We report a case initially diagnosed as SS but ultimately diagnosed as T-PLL based upon skin involvement.
  
  
  METHODS
  A 70-year-old man was referred by his hematologist for management of SS. Physical examination revealed lymphadenopathies and mild diffuse erythema without infiltration. His WBC count was elevated at 8.3 G/L. A peripheral blood smear showed Sezary-like cells. Flow cytometry of peripheral blood revealed prolymphocytic T-cells staining positively for CD2, CD3, CD4 and CD7. Cytogenetic studies showed chromosomal abnormalities in terms of number and structure with missing chromosomes 6 and13, as well as deletion of chromosome 17. Finally, a diagnosis of T-PLL was made. Pentostatin was initiated pending treatment with alemtuzumab, but the patient's overall condition deteriorated rapidly and he died 10 days later.
  
  
  CONCLUSIONS
  Diagnosis of LPLT is based upon a number of factors. In the case presented herein, the clinically atypical nature of the skin lesions prompted the dermatologist to review the diagnosis. The morphology of the circulating T-lymphocytes and their immunologic and phenotypic characteristics finally ruled out the diagnosis of Sezary syndrome, while their association with compatible cytogenetic anomalies enabled a diagnosis of prolymphocytic leukemia to be made instead.
  
  
  CONCLUSIONS
  Prolymphocytic leukemia involves complex differential diagnosis with regard to Sezary syndrome, posing potential pitfalls for hematologists and dermatologists.
authors.affiliation: Service de dermatologie, centre hospitalier, 194, avenue Rubillard, 72000 Le Mans, France.
authors.forename: P
authors.initials: P
authors.lastname: Dessart
authors.affiliation: Laboratoire d'hématologie-hémostase, centre hospitalier, 194, avenue Rubillard, 72000 Le Mans, France.
authors.forename: P
authors.initials: P
authors.lastname: Lemaire
authors.affiliation: Service d'hématologie, centre Jean-Bernard, 9, rue Beauverger, 72000 Le Mans, France.
authors.forename: K
authors.initials: K
authors.lastname: Le Dû
authors.affiliation: Laboratoire d'anatomopathologie, centre hospitalier, 194, avenue Rubillard, 72000 Le Mans, France.
authors.forename: J
authors.initials: J
authors.lastname: Sandrini
authors.affiliation: Laboratoire d'anatomopathologie, centre hospitalier, 194, avenue Rubillard, 72000 Le Mans, France.
authors.forename: B
authors.initials: B
authors.lastname: Prophette
authors.affiliation: Service de dermatologie, centre hospitalier, 194, avenue Rubillard, 72000 Le Mans, France. Electronic address: hmaillard@ch-lemans.fr.
authors.forename: H
authors.initials: H
authors.lastname: Maillard
mesh_terms: D000230:Adenocarcinoma / Q000628:therapy; D000368:Aged; D000964:Antimetabolites, Antineoplastic / Q000627:therapeutic use; D000069287:Capecitabine / Q000627:therapeutic use; D002872:Chromosome Deletion; D003131:Combined Modality Therapy; D057210:Delayed Diagnosis; D003951:Diagnostic Errors; D017809:Fatal Outcome; D006801:Humans; D016130:Immunophenotyping; D015461:Leukemia, Prolymphocytic, T-Cell / Q000175:diagnosis* / Q000188:drug therapy / Q000235:genetics / Q000473:pathology; D008297:Male; D016609:Neoplasms, Second Primary; D015649:Pentostatin / Q000627:therapeutic use; D012004:Rectal Neoplasms / Q000628:therapy; D012751:Sezary Syndrome / Q000175:diagnosis; D012878:Skin Neoplasms / Q000175:diagnosis* / Q000188:drug therapy / Q000235:genetics / Q000473:pathology; D013601:T-Lymphocytes / Q000473:pathology*
chemical_list: D000964:Antimetabolites, Antineoplastic; D015649:Pentostatin; D000069287:Capecitabine
keywords: Erythroderma; Leucémie prolymphocytaire T; Sezary syndrome; Syndrome de Sézary; T-cell prolymphocytic leukemia; Érythrodermie