Unusual Cutaneous Histiocytosis Expressing an Intermediate Immunophenotype Between Langerhans' Cells and Dermal Macrophages

Abstract

Cutaneous histiocytosis was discovered in a 40-year-old man with a slow-growing nodule located on his right arm. Histologic findings showed an epidermotropic infiltrate of histiocytes with folded, irregular nuclei. Immunologically, the cells presented an intermediate phenotype between Langerhans' cells and dermal macrophages. After surgical removal of the lesion, neither a relapse nor visceral involvement was observed during two years of follow-up.

Unusual variants of non-Langerhans cell histiocytoses

“…5,16,18,20,24 In summary, these cells display similar histologic and antigenic features to LC. Ultrastructurally, however, they differ in that Birbeck granules are absent.…”

“…Two clinical subtypes seem to predominate: a solitary nodular form [11][12][13][14]16 (Fig 1, A) and a multiple papulonodular form 3,5,6,[8][9][10]15,[17][18][19][20][21][22][23][24][25][26] (Fig 1, B). The former is usually characterized by a single, soft red asymptomatic nodule about 1 cm in diameter; the latter presents with a widespread eruption of multiple, firm asymptomatic lesions ranging in size from a few millimeters to 1 cm, varying in color from dark red to brownish and covered by intact skin.…”

“…Based on a review of the literature that includes the recent report by Ratzinger et al, 4 15 patients presenting with solitary lesions and showing a benign clinical course exist [11][12][13][14]16 ; among these, two patients presented at birth with a solitary nodule that spontaneously regressed 12 or was removed by shave excision 13 without relapse, respectively.…”

Lymph Nodes

“…526,535,536 Indeterminate dendritic cell tumors, which often test positive for CD1 and S-100 protein but lack the Birbeck granules and grooved nuclei of Langerhans cells, most often occur in skin and rarely in lymph nodes. These are extremely rare lesions.…”

Solitary cutaneous dendritic cell tumor in a child: Role of dendritic cell markers for the diagnosis of skin Langerhans cell histiocytosis

“…This disorder appears to occur in adults, and only a few cases have been reported as a solitary variant. [31][32][33] In our case, we can exclude a proliferative process of the indeterminate cell because of the missing expression of CD68.…”