Dermatology: Practical and Conceptual


Image Letter | Dermatol Pract Concept. 2022;12(4):e2022131 1

Necrobiotic Xanthogranuloma as Sign  
of Monoclonal Gammopathy

Claudio Conforti1, Iris Zalaudek1

1 Dermatology Clinic, Maggiore Hospital, Piazza dell’Ospitale 1, University of Trieste, Trieste, Italy

Citation: Conforti C, Zalaudek I. Necrobiotic Xanthogranuloma as Sign of Monoclonal Gammopathy. Dermatol Pract Concept. 
2022;12(4):e2022131. DOI: https://doi.org/10.5826/dpc.1204a131

Accepted: January 9, 2022; Published: October 2022

Copyright: ©2022 Conforti et al. This is an open-access article distributed under the terms of the Creative Commons  
Attribution-NonCommercial License (BY-NC-4.0), https://creativecommons.org/licenses/by-nc/4.0/, which permits unrestricted 
noncommercial use, distribution, and reproduction in any medium, provided the original authors and source are credited.

Funding: None.

Competing interests: None.

Authorship: All authors have contributed significantly to this publication.

Corresponding author: Claudio Conforti, MD, Dermatology Clinic, Hospital Maggiore, Trieste, Italy. Phone number: +39 3335441549, 
E-mail address: claudioconforti@yahoo.com

Case presentation

A 52-year-old woman referred to our skin cancer unit for 

the presence of yellow periorbital plaques that enlarged 

over the past decade. Based on the clinical and dermoscopic 

presentations (Figure 1), a clinical diagnosis of necrobiotic 

xanthogranuloma (NX) was suspected. A  full laboratory 

workup was performed including skin and bone marrow 

 biopsy, CT scan of the orbital region and urine  examination. 

Tests revealed an IgG paraproteinemia without bone 

 involvement and, based on skin biopsy, the diagnosis of NX 

BRAF wild type was confirmed.

Figure 1. (A) Clinical appearance of necrobiotic xanthogranuloma showing eyelid and periorbital yellow plaques. (B)  Dermoscopic  features 

of XN showing yellow structureless areas that correspond to the presence of histiocytes in the dermis. (C) H&E histological detail showing 

foamy histiocytes in the dermis.



2 Image Letter | Dermatol Pract Concept. 2022;12(4):e2022131

Teaching Point

Necrobiotic xanthogranuloma is a rare  manifestation of 

non-Langerhans histiocytosis and it is often associated with 

monoclonal gammopathy.

References

1. Spicknall KE, Mehregan DA. Necrobiotic xanthogranuloma. 

Int J Dermatol. 2009;48(1):1-10. DOI: 10.1111/j.1365-4632. 

2009.03912.x. PMID: 19126043