Nontuberculous mycobacterium genital infection mimicking donovanosis in a patient with hairy cell leukemia

Recommendations for the Management of Patients with Hairy-Cell Leukemia and Hairy-Cell Leukemia-like Disorders: A Work by French-Speaking Experts and French Innovative Leukemia Organization (FILO) Group

INTRODUCTION

Hairy-cell leukemia (HCL) is a rare B-cell chronic lymphoproliferative disorder (B-CLPD), whose favorable prognosis has changed with the use of purine nucleoside analogs (PNAs), such as cladribine (CDA) or pentostatin (P). However, some patients eventually relapse and over time HCL becomes resistant to chemotherapy. Many discoveries have been made in the pathophysiology of HCL during the last decade, especially in genomics, with the identification of the BRAFV600E mutation and cellular biology, including the importance of signaling pathways as well as tumor microenvironment. All of these new developments led to targeted treatments, especially BRAF inhibitors (BRAFis), MEK inhibitors (MEKis), Bruton's tyrosine kinase (BTK) inhibitors (BTKis) and recombinant anti-CD22 immunoconjugates.

RESULTS

The following major changes or additions were introduced in these updated guidelines: the clinical relevance of the changes in the classification of splenic B-cell lymphomas and leukemias; the increasingly important diagnostic role of BRAFV600E mutation; and the prognostic role of the immunoglobulin (IG) variable (V) heavy chain (H) (IGHV) mutational status and repertory. We also wish to insist on the specific involvement of bones, skin, brain and/or cerebrospinal fluid (CSF) of the disease at diagnosis or during the follow-up, the novel targeted drugs (BRAFi and MEKi) used for HCL treatment, and the increasing role of minimal residual disease (MRD) assessment.

CONCLUSION

Here we present recommendations for the diagnosis of HCL, treatment in first line and in relapsed/refractory patients as well as for HCL-like disorders including HCL variant (HCL-V)/splenic B-cell lymphomas/leukemias with prominent nucleoli (SBLPN) and splenic diffuse red pulp lymphoma (SDRPL).

Skin changes in hairy cell leukemia

Skin lesions have been reported in about 10–12% of hairy cell leukemia (HCL) patients. Most are etiologically related to autoimmune or infectious processes, although secondary cutaneous neoplasms and drug-induced lesions are also reported. However, leukemia cutis with the direct infiltration of the skin by leukemic cells is extremely rare in HCL patients. This paper reviews the epidemiology, pathogenesis, clinical symptoms, diagnosis, and approach to treating skin lesions in HCL. A literature review of the MEDLINE database for articles in English concerning hairy cell leukemia, skin lesions, leukemia cutis, adverse events, infectious, cutaneous, drug reactions, neutrophilic dermatoses, secondary neoplasms, and vasculitis was conducted via PubMed. Publications from January 1980 to September 2020 were scrutinized. Additional relevant publications were obtained by reviewing the references from the chosen articles.