Periorbital Necrobiotic Xanthogranuloma Successfully Treated with Intravenous Immunoglobulin

Monoclonal gammopathies of clinical significance (MGCS): In pursuit of optimal treatment

Monoclonal gammopathy of clinical significance (MGCS) represents a new clinical entity referring to a myriad of pathological conditions associated with the monoclonal gammopathy of undetermined significance (MGUS). The establishment of MGCS expands our current understanding of the pathophysiology of a range of diseases, in which the M protein is often found. Aside from the kidney, the three main organ systems most affected by monoclonal gammopathy include the peripheral nervous system, skin, and eye. The optimal management of these MGUS-related conditions is not known yet due to the paucity of clinical data, the rarity of some syndromes, and limited awareness among healthcare professionals. Currently, two main treatment approaches exist. The first one resembles the now-established therapeutic strategy for monoclonal gammopathy of renal significance (MGRS), in which chemotherapy with anti-myeloma agents is used to target clonal lesion that is thought to be the culprit of the complex clinical presentation. The second approach includes various systemic immunomodulatory or immunosuppressive options, including intravenous immunoglobulins, corticosteroids, or biological agents. Although some conditions of the MGCS spectrum can be effectively managed with therapies aiming at the etiology or pathogenesis of the disease, evidence regarding other pathologies is severely limited to individual patient data from case reports or series. Future research should pursue filling the gap in knowledge and finding the optimal treatment for this novel clinical category.

Systemic therapy of necrobiotic xanthogranuloma: a systematic review

BACKGROUND

Even though a plethora of systemic therapies have been proposed for necrobiotic xanthogranuloma (NXG), there is no systematic review on this topic in literature.

OBJECTIVE

To review all existing literature on the systemic therapy of NXG in order to identify the most effective therapies.

METHODS

All reported papers in the literature were screened for systemic treatments of NXG. Papers without proper description of the therapies, papers describing topical therapy, and articles without assessment of effectiveness were excluded. Subsequently, we analyzed 79 papers and a total of 175 cases.

RESULTS

The most effective treatments for NXG are intravenous immunoglobulins (IVIG), corticosteroids, and combination therapies including corticosteroids.

CONCLUSIONS

Corticosteroids and IVIG should therefore be considered first-line treatments in patients with NXG.

Long-standing necrobiotic xanthogranuloma limited to the skin: A case report

Necrobiotic xanthogranuloma is a rare non-Langerhans cell histiocytosis with a known association with monoclonal gammopathies and malignant conditions. There is a lack of consensus regarding the management of necrobiotic xanthogranuloma. In this case report, the patient is diagnosed with a long-standing necrobiotic xanthogranuloma limited to the skin. Although all initial investigations were reassuring, the patient remains at a higher risk of developing a malignant condition. The goal of the authors is to highlight the need for clearer investigation and follow-up guidelines.

A Multicenter Cross-Sectional Study and Systematic Review of Necrobiotic Xanthogranuloma With Proposed Diagnostic Criteria

Importance

Necrobiotic xanthogranuloma (NXG) is a non-Langerhans cell histiocytosis classically associated with paraproteinemia attributable to plasma-cell dyscrasias or lymphoproliferative disorders. Despite the morbidity of NXG, the literature is limited to case reports and small studies, and diagnostic criteria are lacking.

Objective

To evaluate the characteristics of NXG and propose diagnostic criteria.

Design, Setting, and Participants

This multicenter cross-sectional study was conducted at tertiary academic referral centers and followed by a systematic review and a consensus exercise. The multicenter cohort included patients with NXG diagnosed at the Brigham and Women's and Massachusetts General Hospitals (2000-2018), the University of Iowa Hospitals and Clinics (2000-2018), and the University of Pennsylvania Health System (2008-2018). The systematic review was conducted in 2018 and included patients with NXG identified in the Cochrane, Ovid EMBASE, PubMed, and Web of Science databases. The consensus exercise was conducted by 8 board-certified dermatologists to identify diagnostic criteria.

Main Outcomes and Measures

Demographic factors, comorbidities, clinical features, and treatment response.

Results

Of 235 included patients with NXG (34 from the multicenter cohort and 201 from the systematic review results), the mean (SD) age at presentation was 61.6 (14.2) years; 147 (62.6%) were female. Paraproteinemia was detected in 193 patients (82.1%), most often IgG-κ (117 patients [50.0%]). A malignant condition was detected in 59 patients (25.1%), most often multiple myeloma (33 patients [14.0%]). The overall rate of paraproteinemia and/or a malignant condition was 83.8% (197 patients). In the multicenter cohort, evolution of paraproteinemia into multiple myeloma was observed up to 5.7 years (median [range], 2.4 [0.1-5.7] years) after NXG presentation. Cutaneous lesions consisted of papules, plaques, and/or nodules, typically yellow or orange in color (113 of 187 [60.4%]) with a periorbital distribution (130 of 219 [59.3%]). The eye was the leading site of extracutaneous involvement (34 of 235 [14.5%]). In the multicenter cohort, intravenous immunoglobulin had the best treatment response rate (9 of 9 patients [100%]), followed by antimalarial drugs (4 of 5 patients [80%]), intralesional triamcinolone (6 of 8 patients [75%]), surgery (3 of 4 patients [75%]), chemotherapy (8 of 12 patients [67%]), and lenalidomide or thalidomide (5 of 8 patients [63%]). The consensus exercise yielded 2 major criteria, which were (1) clinical and (2) histopathological features consistent with NXG, and 2 minor criteria, consisting of (1) paraproteinemia, plasma-cell dyscrasia, and/or other associated lymphoproliferative disorder and (2) periorbital distribution of cutaneous lesions. In the absence of foreign body, infection, or another identifiable cause, fulfillment of both major and at least 1 minor criterion were proposed to establish the diagnosis of NXG.

Conclusions and Relevance

Necrobiotic xanthogranuloma is a multisystem disorder associated with paraproteinemia and malignant conditions. The proposed diagnostic criteria may advance clinical research and should be validated.

Adult xanthogranulomatous disease of the orbit: case report of spontaneous regression and review of treatment modalities

Adult xanthogranulomatous disease of the orbit is a rare and incompletely understood entity. It can be limited to the orbit or be associated with systemic disease. While routine systemic surveillance is the standard of care for patients with orbital xanthogranulomatous disease, there is no universally accepted protocol for managing periorbital and orbital involvement. The authors report a case of adult orbital xanthogranuloma, without systemic disease, who, after 10 years of observation, demonstrated sustained radiographic regression of the lesions. To the authors' knowledge, this represents one of the first reports of spontaneous regression of untreated orbital xanthogranuloma, and supports observation of lesions that do not compromise ocular function. We present our case in the context of a major review of various treatment strategies described in the literature, including surgical resection, radiotherapy, plasmapheresis, corticosteroids, multiple immunomodulatory medications.