Rosai-Dorfman disease with a concurrent mantle cell lymphoma

Intracranial Rosai‑Dorfman disease complicated by mucosa‑associated lymphoid tissue: A case report

Intracranial Rosai-Dorfman disease (RDD) is a rare, self-limiting histiocytic disease of unknown etiology. Extranodal marginal zone lymphoma of the mucosa-associated lymphoid tissue (MALT lymphoma) is also rare and intracranial RDD complicated by MALT lymphoma is even rarer. The present study reports a case of a 55-year-old female who was admitted to The Second Affiliated Hospital of Jiaxing University (Jiaxing, China) with headache for half a month and ptosis of the right eyelid for 4 days. Computerised tomography and magnetic resonance imaging revealed a right parasellar tumor and, subsequently, subtotal resection of the tumor was performed. Postoperative pathology revealed intracranial RDD complicated by MALT lymphoma. The patient received chemotherapy after surgery and achieved good therapeutic effects. After 12 months of follow-up, the residual tumor disappeared and the ptosis prominently improved. To the to the best of the authors' knowledge, the present case is the first reported case of an adult intracranial RDD complicated by MALT lymphoma.

How I Diagnose Rosai-Dorfman Disease

OBJECTIVES

Rosai-Dorfman disease (RDD) is one of 3 major types of histiocytosis, along with Erdheim-Chester disease and Langerhans cell histiocytosis. While historically, RDD was considered a benign self-limited condition, current data show MAPK/ERK pathway mutations in 30% to 50% of cases, indicative of a clonal process. Rosai-Dorfman disease was incorporated as a histiocytic neoplasm in the fifth edition of the World Health Organization classification of hematopoietic tumors and the International Consensus Classification.

METHODS

We discuss the diagnosis of RDD using 2 illustrative cases, interpretative challenges, and a diagnostic algorithm.

RESULTS

Rosai-Dorfman disease involves nodal and extranodal sites, including skin, sinuses, salivary gland, orbit, central nervous system, kidney, and bone. In a subset, RDD can coexist with other neoplasms (lymphomas, other histiocytosis) or autoimmune disease. Morphologically, RDD histiocytes are characterized by enlarged round to oval nuclei, distinct nucleoli, and voluminous cytoplasm with engulfment of inflammatory cells (emperipolesis). By immunohistochemistry, they express CD68, CD163 (majority), S100, OCT2, and cyclin D1. Appropriate use of ancillary studies is important to support the diagnosis of RDD while excluding other histiocytic neoplasms and reactive histiocytic proliferations.

CONCLUSIONS

Management of RDD is dependent on the extent of organ involvement and clinical symptoms. In patients who require therapy, next-generation sequencing is recommended to identify MAPK/ERK pathway mutations for targeted therapy.

Painless cervical lymphadenopathy in an elderly patient – a rare case of Rosai-Dorfman disease and Hodgkin's lymphoma

Rosai-Dorfman disease (RDD) is a rare, benign disease with extensive lymphadenopathy. In this case, an 81-year-old gentleman with previous pulmonary tuberculosis presented painless cervical lymphadenopathy associated with generalized weakness, loss of appetite, and cough. The causes of cervical lymphadenopathy in the elderly are comprehensive; thorough history, examination, and appropriate investigations are vital in diagnosing diseases. A lymph node biopsy is recommended if blood investigations and imaging are inconclusive. He was later diagnosed with RDD associated with Hodgkin’s lymphoma, and dexamethasone treatment was initiated. Concomitant diagnoses are rare but should not be disregarded. This case report is a reminder that RDD remains a differential diagnosis of cervical lymphadenopathy. Regular monitoring is required as immune dysregulation from the treatment of RDD may exacerbate quiescently treated pulmonary tuberculosis.

Ocular Adnexal MALT Lymphoma in Association With Rosai-Dorfman Disease in a Child

A 12-year-old boy presented with persistent proptosis and periorbital swelling after a school altercation. MRI revealed a mass in the right superonasal orbit extending along the orbital roof to the frontal bone and right frontal sinus, and intracranially to the dura of the right frontal lobe. Immunohistochemistry revealed CD20- and CD43-positive B cells consistent with a low-grade B-cell lymphoma. The patient was diagnosed with stage I ocular adnexal MALT lymphoma and treated with radiation therapy, followed by systemic chemotherapy. However, an enhancing orbital and intracranial mass remained on follow-up imaging, leading to a repeat biopsy, which was consistent with a diagnosis of Rosai-Dorfman disease. This is the first reported pediatric case of ocular adnexal MALT lymphoma with subsequent development of Rosai-Dorfman disease.

NRAS Mutations May Be Involved in the Pathogenesis of Cutaneous Rosai Dorfman Disease: A Pilot Study

Background: Purely cutaneous Rosai-Dorfman disease (RDD) is a rare histiocytic proliferative disorder limited to the skin. To date, its pathogenesis remains unclear. Owing to recent findings of specific mutations in the mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) pathway in histiocytic proliferative disorders, it provides a novel perspective on the pathomechanism of cutaneous RDD. We aim to investigate the genomic mutations in MAPK/ERK pathway in cutaneous RDD. Methods: We retrospectively recruited all cases of cutaneous RDD from two hospitals in Taiwan from January 2010 to March 2020 with the clinicopathologic features, immunohistochemistry, and treatment. Mutations of neuroblastoma RAS viral oncogene homolog (NRAS), Kirsten rat sarcoma 2 viral oncogene homolog (KRAS), and v-raf murine sarcoma viral oncogene homolog B1 (BRAF) in MAPK/ERK pathway were investigated by the highly sensitive polymerase chain reaction with Sanger sequencing. Results: Seven patients with cutaneous RDD were recruited with nine biopsy specimens. The median age was 46 years (range: 17–62 years). Four of seven patients (57.1%) received tumor excision, while the other three chose oral and/or topical or intralesional steroids. NRAS mutation was detected in 4 of 7 cases (4/7; 51.7%), and NRAS A146T was the most common mutant point (n = 4/7), followed by NRAS G13S (n = 2/7). There is no KRAS or BRAF mutation detected. Conclusions: We report the NRAS mutation is common in cutaneous RDD, and NRAS A146T was the most frequent mutation in this cohort. Mutations in the NRAS gene can activate the RAS/MAPK signaling and have been reported to be associated with various cancers. It indicates that NRAS mutation in MAPK/ERK pathway may involve the pathogenesis of cutaneous RDD.

Rosai-Dorfman disease: an overview

CONTEXT

Rosai-Dorfman disease is an uncommon histiocytic disorder most frequently presenting as bilateral cervical lymphadenopathy in children and young adults. Extranodal disease occurs in a significant proportion of patients. It has been recently classified as part of the 'R group' of histiocytoses by the Histiocyte Society in 2016. Cutaneous Rosai-Dorfman disease is regarded as a separate disease entity that falls into the 'C group' of histiocytoses according to this classification system. The pathogenesis was previously poorly understood; however, recent evidence demonstrating clonality in a subset of cases raises the possibility of a neoplastic process. A possible association with IgG4-related disease remains controversial.

OBJECTIVES

To provide a comprehensive review of Rosai-Dorfman disease, including nodal, extranodal and cutaneous forms, with a particular emphasis on new insights into the possible clonal nature of the disease; to discuss the recently revised classification of the histiocytoses by the Histiocyte Society; and to summarise the findings from the literature regarding the controversial association with IgG4-related disease.

DATA SOURCES

This review is based on published peer-reviewed English literature.

CONCLUSIONS

Classic Rosai-Dorfman disease, which may be sporadic or familial, is considered a separate entity from cutaneous disease, which is reflected in the revised classification of histiocytoses. An increase in IgG4-positive plasma cells may be seen in Rosai-Dorfman disease. This finding in isolation is of limited significance and should be interpreted with caution. Studies investigating the molecular profile of the disease show that in at least a subset of cases the disease is a clonal process. The classification of Rosai-Dorfman disease is therefore likely to change as our understanding of the aetiopathogenesis evolves.