Émilie Laban1, Marie Beylot-Barry2, Nicolas Ortonne3, Maxime Battistella4, Agnes Carlotti5, Anne de Muret6, Janine Wechsler3, Brigitte Balme7, Tony Petrella8, Laurence Lamant9, Éric Frouin10, Jean-Philippe Merlio11, Béatrice Vergier12. 1. Service de pathologie, hôpital Haut-Lévêque, CHU de Bordeaux, avenue de Magellan, 33604 Pessac cedex, France. Electronic address: emiliell@hotmail.com. 2. Service de dermatologie, hôpital Haut-Lévêque, CHU de Bordeaux, avenue de Magellan, 33604 Pessac cedex, France. 3. Département de pathologie, hôpital Henri-Mondor, 51, avenue du Maréchal-de-Lattre-de-Tassigny, 94010 Créteil cedex, France. 4. Service de pathologie, hôpital Saint-Louis, 1, avenue Claude-Vellefaux, 75475 Paris cedex 10, France. 5. Service de pathologie, hôpital Cochin, 27, rue du Faubourg-Saint-Jacques, pavillon Gustave-Roussy, 75679 Paris cedex 14, France. 6. Service de pathologie, hôpital Trousseau, CHRU de Tour, avenue de la République, 37170 Chambray-les-Tours, France. 7. Service de pathologie, centre hospitalier Lyon Sud, 165, chemin du Grand-Revoyet, pavillon 3D, 69495 Pierre-Bénite cedex, France. 8. Service de pathologie, plateau technique de biologie, CHU de Dijon, 2, rue A.-Ducoudray, BP 37013, 21070 Dijon cedex, France. 9. Département de pathologie, institut universitaire du cancer de Toulouse, Oncopole, 1, avenue Irène-Joliot-Curie, 31059 Toulouse cedex 9, France. 10. Service de pathologie, CHU de Poitiers, 2, rue de la Milétrie, La Milétrie, BP 577, 86021 Poitiers cedex, France. 11. Service de biologie des tumeurs, hôpital Haut-Lévêque, CHU de Bordeaux, avenue de Magellan, 33604 Pessac cedex, France. 12. Service de pathologie, hôpital Haut-Lévêque, CHU de Bordeaux, avenue de Magellan, 33604 Pessac cedex, France.
Abstract
INTRODUCTION: Taking as a base our retrospective study of 2760 cases of cutaneous lymphoproliferations from the LYMPHOPATH and GFELC networks, we analyzed the doubtful and discordant cases between non-expert and expert pathologists, and the interest of clinicopathological confrontation. MATERIAL AND METHODS: We defined the main diagnostic difficulties presented by cutaneous lymphoproliferations. We then designed and tested the algorithms on 20 random cases with 20 pathologists, in order to be used by any pathologist (not necessarily specialised in dermatopathology). RESULTS: The problematic differential diagnoses most frequently encountered are the following: MF or reactive dermatose; lymphoma without any other precision or reactive infiltrate; small B cell lymphoproliferation: lymphoma or reactive infiltrate; phenotyping of large B cell lymphoproliferation. We also analyzed less common problematic differential diagnoses, on the grounds that they are over- or under- diagnosed. Our test had a 72% success rate among the 20 randomly tested cases. The use of several algorithms for the same case is possible. DISCUSSION: Our study shows that an expert second-opinion is of interest in the area of cutaneous lymphoproliferations. A second opinion is useful for distinguishing a small B cell lymphoma from a HLR, and for defining a final diagnosis when the first pathologist doubts between lymphoma and reactive infiltrate. However, we demonstrate that for the problem MF or reactive dermatose, an initial clinicopathological confrontation produces more results than a second-opinion pathology review. CONCLUSION: This is the first study of cutaneous lymphoproliferations that, without excluding reactionary infiltrates, concentrates on doubtful and discordant diagnoses between non expert and expert pathologists, and which has produced tested diagnostic algorithms.
INTRODUCTION: Taking as a base our retrospective study of 2760 cases of cutaneous lymphoproliferations from the LYMPHOPATH and GFELC networks, we analyzed the doubtful and discordant cases between non-expert and expert pathologists, and the interest of clinicopathological confrontation. MATERIAL AND METHODS: We defined the main diagnostic difficulties presented by cutaneous lymphoproliferations. We then designed and tested the algorithms on 20 random cases with 20 pathologists, in order to be used by any pathologist (not necessarily specialised in dermatopathology). RESULTS: The problematic differential diagnoses most frequently encountered are the following: MF or reactive dermatose; lymphoma without any other precision or reactive infiltrate; small B cell lymphoproliferation: lymphoma or reactive infiltrate; phenotyping of large B cell lymphoproliferation. We also analyzed less common problematic differential diagnoses, on the grounds that they are over- or under- diagnosed. Our test had a 72% success rate among the 20 randomly tested cases. The use of several algorithms for the same case is possible. DISCUSSION: Our study shows that an expert second-opinion is of interest in the area of cutaneous lymphoproliferations. A second opinion is useful for distinguishing a small B cell lymphoma from a HLR, and for defining a final diagnosis when the first pathologist doubts between lymphoma and reactive infiltrate. However, we demonstrate that for the problem MF or reactive dermatose, an initial clinicopathological confrontation produces more results than a second-opinion pathology review. CONCLUSION: This is the first study of cutaneous lymphoproliferations that, without excluding reactionary infiltrates, concentrates on doubtful and discordant diagnoses between non expert and expert pathologists, and which has produced tested diagnostic algorithms.