A patient with widespread firm nontender nodules

A 63-year-old man with a history of chronic myelomonocytic leukemia (CMML) presented 2 month widespread nonpainful skin lesions. Otherwise he felt well and reported no systemic symptoms. On examination, there were nontender violaceous, firm nodules on his face, torso, arms, legs; some lesions appeared ‘bruise-like’ (Fig 1, B). An urgent diagnostic biopsy showed dermis widely infiltrated by monomorphic blasts 2, Immunohistochemistry revealed the lesional cells strongly expressed CD4, CD43, CD45, CD56, CD123 C), BCL2. Treatment novel therapy, Tagraxofusp, over 3 months led to significant improvement resolution cutaneous lesions.Fig 2View Large Image Figure ViewerDownload Hi-res image Download (PPT) Question 1: What is most likely underlying diagnosis?A.Blastic plasmacytoid dendritic cell neoplasm (BPDCN)B.Leukemia cutis secondary CMMLC.SarcoidosisD.Cutaneous T-cell lymphoma (CTCL)E.Kaposi sarcoma Answers:A.Blastic (BPDCN) – Correct. BPDCN rare hematological malignancy caused clonal proliferation precursors cells. It often presents brown or purple nodular (although bruise-like patches also occur) which can be numerous solitary. The histopathology immunohistochemistry described in are typical BPDCN.1Pagano L. Valentini C.G. Grammatico S. Pulsoni A. Blastic neoplasm: criteria therapeutical approaches.Br J Haematol. 2016; 174: 188-202https://doi.org/10.1111/bjh.14146Crossref PubMed Scopus (117) Google ScholarB.Leukemia CMML Incorrect. Leukemia unlikely diagnosis due positivity for CD123, as negativity myeloperoxidase.C.Sarcoidosis No granulomas seen histology. infiltrate composed would not consistent sarcoidosis.D.Cutaneous (CTCL) CTCL show wide variety morphological immunohistochemical features, but cases classic markers - CD2, CD3, CD5 CD7 although individual CTCLs drop one more these markers. an unusual marker positive CTCL.E.Kaposi develop Kaposi absence HIV infection strong immunosuppression. Histochemical had required any active treatment. histology did atypical spindle proliferation. 2: Which following statements regarding presentation this condition correct?A.It present without bone marrow involvement leukemic disseminationB.Extracutaneous disease including lymphadenopathy, splenomegaly, hepatomegaly rareC.The typically extends from into epidermisD.The malignant clone arises directly CMMLE.Dual CD4 CD56 allows made Answers:A.It dissemination In case, patient only symptoms was evidence biopsy. However, occur patients acute leukemia.1Pagano ScholarB.Extracutaneous Lymphadenopathy, common sites extracutaneous BPDCN. They have been 56%, 44%, 42%, respectively.2Pagano et al.Blastic presentation: Italian multicenter study.Haematologica. 2013; 98: 239-246https://doi.org/10.3324/haematol.2012.072645Crossref (215) ScholarC.The epidermis histological feature ‘grenz zone’. This area sparing papillary dermis. does extend epidermis.D.The separate CMML-1. genomic analysis suggests that conditions arise shared founding clone. Concurrent myeloid malignancies than 20% BPDCN, particularly common.3Batta K. Bossenbroek H.M. Pemmaraju N. al.Divergent evolution blastic TET2-mutated origin.Leukemia. 2021; 35: 3299-3303https://doi.org/10.1038/s41375-021-01228-yCrossref (12) ScholarE.Dual Diagnosis requires specific These include CD303, TCL1. lineage-specific B required.1Pagano Scholar 3: management prognosis has good prognosisB.Younger age at prognostic poor outcomeC.Traditional myeloablative chemotherapy yielded excellent responsesD.Hematopoietic stem transplantation (HSCT) enable long-term remissionsE.Relapse remission extremely rapid progression median survival 12-14 months.B.Younger outcome Age under 40 years confer favorable prognosis.C.Traditional responses Although initial response may seen, limited benefit. Acute lymphoblastic regimens, regimens used non-Hodgkin used.1Pagano ScholarD.Hematopoietic remissions aim induction achieve act bridge HSCT. Overall 3-year 41% HSCT reported.4Aoki T. Suzuki R. Kuwatsuka Y. al.Long-term autologous allogeneic neoplasm.Blood. 2015; 125: 3559-3562https://doi.org/10.1182/blood-2015-01-621268Crossref (91) therapy recently approved treatment shown promising clinical responses. cytotoxin consisting recombinant human interleukin (or receptor) fused truncated diphtheria toxin targets CD123. Tagraxofusp given intravenous infusion dose 7 12 micrograms per kilogram body weight day 1 5 each 21 cycle. As traditional chemotherapy, it HSCT.5Pemmaraju Lane A.A. Sweet K.L. al.Tagraxofusp dendritic-cell neoplasm.N Engl Med. 2019; 380: 1628-1637https://doi.org/10.1056/NEJMoa1815105Crossref (218) Unfortunately, despite our suffered relapse prior undergoing HSCT.E.Relapse regularly relapses contributing its prognosis.2Pagano None disclosed. We thank consent publication their case details images.