Sarah Stien, Eric Durot, Anne Durlach, Marie Beylot-Barry, Henri Adamski, Helmut Beltraminelli, Gérôme Bohelay, Agnès Carlotti, Olivier Carpentier, Pascale Cornillet, Romain Dubois, Nathalie Franck, Bérengère Husson, Liliane Laroche, Eve Maubec, Christian Le Clech, Laurent Machet, Nicolas Ortonne, Caroline Ram-Wolff, Béatrice Vergier, Florent Grange
DOI: 10.2340/00015555-3535

Cutaneous involvement in Waldenström’s macroglobulinaemia (WM) has been poorly characterized. To describe this involvement, a retrospective study of 19 patients with WM and cutaneous involvement of tumour B cells was performed. Twelve patients (group 1) had lymphoplasmacytic, non-transformed cutaneous proliferation, while in 7 cases (group 2) cutaneous involvement corresponded to histological transformation. In group 1, skin involvement was inaugural in 6 cases. The lesions were infiltrated plaques (83%), papules (25%) and tumours (42%). Four patients had a similar clinical picture (purplish, bilateral and symmetrical infiltration on the face). MYD88 L265P mutation was detected in the skin biopsy in all 6 cases tested. The 3-year specific survival rate was 88%. In group 2, cutaneous transformation occurred during the follow-up of the WM (71%). Lesions presented as ulcerated tumours (86%) of the trunk (57%) and lower limbs (57%). The 3-year specific survival rate was 22%. Skin involvement in WM has distinctive characteristics (e.g. clinical, histological, immunohistochemical, MYD88 L265P mutation).

Skin involvement in Waldenström’s macroglobulinaemia is poorly described, and diagnosis of this disorder may be difficult. Many differential diagnoses are possible (other lymphomas, primary cutaneous lymphoma, etc.). Describing 2 aspects of Waldenström’s macroglobulinaemia (infiltration by lymphoplasmacytic tumour cells or histological transformation into diffuse large B-cell lymphoma) allows the identification of clinical, histological and immunohistochemical diagnostic aids. Detection of the MYD88 L265P mutation is of interest. This study identified a characteristic clinical picture in non-transformed cases, and was able to distinguish between transformed and non-transformed cases by their severity and poor prognosis.