Indeterminate Cell Histiocytosis in Association with Acute Myeloid Leukemia

Abstract

Indeterminate cell histiocytosis (ICH) is a rare proliferative disorder, in which the predominant cells share morphologic and immunophenotypic features from both Langerhans and non-Langerhans cell histiocytosis. We describe a 62-year-old man presenting a 2-month history of firm nodular lesions on the upper lip. Histopathology, immunohistochemical, and ultrastructural analysis showed typical findings of ICH. The patient was treated with thalidomide and almost complete regression of the lesions was reached within 7 months. Nevertheless, one month after remission, he developed an acute myeloid leukemia of the subtype monocytic leukemia (M5). The patient's condition rapidly worsened and he died due to a respiratory failure four weeks later. We present this case because apart of being rare it joins the effectiveness of thalidomide and the association with an acute monocytic leukemia. A review of the literature is made.

Indeterminate cell histiocytosis with naïve cells

“…Late stages of LCH may completely loss LC markers and then consist mainly of xanthomatized macrophages. 15 On the other hand, dermal macrophages have been shown to be capable of induction to differentiate into LC. 16 Furthermore, a common transitional macrophage and/or dendritic cell progenitor is believed to exist between LC, IC, and macrophages.…”

S100-Negative, CD1a-Positive Cutaneous Histiocytosis in a Patient with S100-Positive, CD1a-Positive Pulmonary Histiocytosis

“…[1][2][3] Both macrophages and dendritic cells arise from common progenitor cells in the bone marrow. 2 In the skin, antigen-presenting cells are mainly represented by indeterminate cells, Langerhans cells, and interstitial dendritic cells. 1 Controversy surrounds the origin of these closely related cells.…”

“…Indeterminate cells share features of both Langerhans cells (CD1a + and S100+) and macrophages (CD68 + ) but lack Birbeck granules. 2,4,5 Some believe that indeterminate cells are in fact the precursors to Langerhans cells, which acquire Birbeck granules during their transit from the dermis to the epidermis. 1,2,5 Indeterminate cell histiocytosis (ICH) is a poorly characterized disorder with overlap between Langerhans cell histiocytosis (LCH) and non-LCH.…”

“…1,2,5 Indeterminate cell histiocytosis (ICH) is a poorly characterized disorder with overlap between Langerhans cell histiocytosis (LCH) and non-LCH. 2 …”

“…,6 It is not clear if ICH is a separate entity or if it represents various histiocytic disorders identified at different periods in cellular differentiation 2. …”