title: Frequency and Risk Factors for Associated Lymphomas in Patients With Lymphomatoid Papulosis.
abstract: BACKGROUND
  Lymphomatoid papulosis (LyP) is classified as an indolent cutaneous lymphoma, but outcome dramatically worsens if LyP is associated with lymphoma. The frequency of this association remains unclear in the literature. Here, we assess the frequency and risk factors of association between LyP and another lymphoma in an 11-year retrospective study conducted in 8 dermatology departments belonging to the French Study Group on Cutaneous Lymphoma (FSGCL).
  
  
  METHODS
  Patients with LyP were identified and data extracted from the FSGCL registry between 1991 and 2006. Patients were followed up to January 2014. Age, sex, number of skin lesions, histologic subtype, and genotype were recorded at baseline. Risk factors were determined using univariate and multivariate analysis. Cumulative probability of association was calculated using the Kaplan-Meier method.
  
  
  RESULTS
  We observed 52 cases of lymphomas (cutaneous, n = 38; systemic, n = 14) in 44 of 106 patients (41%). Lymphoma diagnosis was concomitant with or prior to LyP diagnosis in 31 cases and occurred during the course of LyP in 21 cases (cutaneous, n = 14; systemic, n = 7; median delay: 5 years; interquartile range: 1.5-7 years). In multivariate analysis, main prognostic factors for association between LyP and another lymphoma were older age (odds ratio [OR]: 1.05 per year; 95% confidence interval [CI]: 1.01-1.08; p = .011) and presence of a T-cell clone in LyP lesions (OR: 7.55; 95% CI: 2.18-26.18; p = .001).
  
  
  CONCLUSIONS
  Older age and presence of a T-cell clone in LyP lesions are risk factors for associated lymphomas in patients with LyP. These findings should help to identify patients who require close management in clinical practice.
  
  
  CONCLUSIONS
  The management of lymphomatoid papulosis (LyP) is that of an indolent cutaneous lymphoma, based on its excellent prognosis. However, this good prognosis is altered if LyP is associated with lymphoma. Furthermore, risk factors for and frequency of this association remain unclear in the literature. The results presented here demonstrate a high rate of association between LyP and other lymphomas (41%) as well as a long median delay of occurrence (5 years), which emphasizes the need for prolonged follow-up of patients with LyP. Moreover, two main risk factors (i.e., older age and presence of a T-cell clone in LyP lesions) are highlighted, which should help clinical practitioners to identify patients who require close management.
authors.affiliation: Unit of Dermatology and Internal Medicine, Guadeloupe University Hospital and EA 4546, Antilles University, Pointe-à-Pitre, Guadeloupe nadege.cordel@chu-guadeloupe.fr.
authors.forename: Nadège
authors.initials: N
authors.lastname: Cordel
authors.affiliation: Centre d'investigation clinique Antilles-Guyane, INSERM CIC 1424, Pointe-à-Pitre, Guadeloupe.
authors.forename: Benoît
authors.initials: B
authors.lastname: Tressières
authors.affiliation: Department of Dermatology, Clermont-Ferrand University Hospital, University of Auvergne, Clermond-Ferrand, France.
authors.forename: Michel
authors.initials: M
authors.lastname: D'Incan
authors.affiliation: Department of Dermatology, Tours University Hospital and François Rabelais University, Tours, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Machet
authors.affiliation: Department of Dermatology, Robert Debré Hospital and EA 7319, University of Reims Champagne-Ardennes, Reims, France.
authors.forename: Florent
authors.initials: F
authors.lastname: Grange
authors.affiliation: Department of Dermatology, Orléans Regional Hospital, Orléans, France.
authors.forename: Éric
authors.initials: É
authors.lastname: Estève
authors.affiliation: Department of Dermatology, Dijon University Hospital, Dijon, France.
authors.forename: Sophie
authors.initials: S
authors.lastname: Dalac
authors.affiliation: Department of Dermatology, Paris University Hospitals-Henri Mondor, Créteil, France.
authors.forename: Saskia
authors.initials: S
authors.lastname: Ingen-Housz-Oro
authors.affiliation: Department of Dermatology, Paris University Hospitals-St Louis and INSERM U 976, Denis Diderot University, Sorbonne Paris Cité, Paris, France.
authors.forename: Martine
authors.initials: M
authors.lastname: Bagot
authors.affiliation: Department of Dermatology, Bordeaux University Hospital and EA 2406, University of Bordeaux, Bordeaux, France.
authors.forename: Marie
authors.initials: M
authors.lastname: Beylot-Barry
authors.affiliation: Department of Dermatology, Rouen University Hospital and INSERM U 519, Institute for Research and Innovation in Biomedicine, Rouen University, Rouen, Normandy, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Joly
mesh_terms: D000328:Adult; D000368:Aged; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008223:Lymphoma / Q000150:complications / Q000453:epidemiology* / Q000473:pathology; D017731:Lymphomatoid Papulosis / Q000150:complications / Q000453:epidemiology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D012878:Skin Neoplasms / Q000150:complications / Q000453:epidemiology* / Q000473:pathology
keywords: Frequency; Lymphomas; Lymphomatoid papulosis; Risk factors