Langerhans’ cell histiocytosis.

Case 69   Sept 2010 (P. McKee) 

Missed it – looked like PPD or halo naevus with haemosiderin.  Nuclear morphology not obvious. 

Case 524   June 2012  (P. McKee)  M 3 papules on trunk 

This was a case of UP LCH masquerading as LCH. 

Case 682  24.1.13  (H. Diwan)  M 45 lesion nose ?BCC or naevus 

Difficult to see the features discussed.  There must be some views missing.  Mature i-d naevus with naevus giant cells.  Another focus adjacent which apparently showed Langerhans’ Cells (I couldn’t see them).  Discussion about whether this was LCH or just reactive to naevus. 

Case 1160  3.12.14  (H. Diwan)  F 69 vulval pruritus 

Dense papillary dermal infiltrate with cells that were also invading the epidermis.  Cytology rather facetted and not the expected reniform nuclear shape.  No eos either.  CD1a +ve though. 

Case 1270   6.5.15 (H. Diwan)  M 1 scalp 

Small views.  Couldn’t detect LC morphology.  Eos obvious. 

Case 1529  4.5.16  Congential self-healing reticulohistiocytosis 

Case 1574  7.7.16 (A. Bakshi)  M 22 scalp – marked perifollicular erythema (*teaching)  

At last a slide that demonstrates LC cytology!  Unusual presentation of LCH.  Cells showing follicular epidermotropism.  A few eos visible too. Langerin +ve 

Case 1874 3.8.17 (A Bakshi)  M 53 unusual rash axillae and arms (*teaching)  

At last, some nice cytology.  Mitoses++.  Lots of eos. 

Case 2976  2.12.21  (S. Taibjee) F 90 Sub-mammary rash.  Recent transformation of CML. 

Rash looked like florid candidiasis.  However, infiltrate is too dense and epidermotropic to be reactive.  Cells lacked the dendritic morphology of reactive Langerhans’ cells.  Eosinophils prominent.  CD1a strong +ve;  Langerin +ve; CD123 minimal; PAS -ve. 

Note: LCH presenting in adults is often associated with myeloproliferative disease. 

Refs: 1. Yohe SL, Chenault CB, Torlakovic EE, Asplund SL, McKenna RW. Langerhans cell histiocytosis in acute leukemias of ambiguous or myeloid lineage in adult patients: support for a possible clonal relationship. Mod Pathol. 2014 May;27(5):651-6.  

2. Pina-Oviedo S, Torres-Cabala CA, Miranda RN, Tetzlaff MT, Singh S, Rapini RP, Prieto VG, Aung PP. Concomitant Cutaneous Langerhans Cell Histiocytosis and Leukemia Cutis. Am J Dermatopathol. 2017 May;39(5):388-392.  

 Case 3013  24.1.22 (M. Abdel-Halim) F 11 lesions scalp, face, labia majora. Polyuria/polydipsia 

Multisystem LCH.  CD1a +ve. 

Case 4122 8.11.22 (U. Sundram)  M 48 lesion on chest 

Dermal infiltrate with histiocytoid cells, some showing reniform nuclei; eos + 

Case 4506 29.4.24 (M. Abdel-Halim) F 43 Resistant intertriginous and scalp rash 

Clinical history suggests the diagnosis.  General pattern of histology confirms it, although slide reproduction not very good at higher power.