Consensus recommendations for the diagnosis and clinical management of Rosai-Dorfman-Destombes disease

Recurrent central nervous system Rosai-Dorfman disease with KRAS mutation: a case report

BACKGROUND

Rosai-Dorfman disease (RDD) is a rare, non-Langerhans cell histiocytosis of unknown etiology. we report a very rare case of recurrent central nervous system RDD with KRAS gene mutation and review the literature to improve our understanding of this disease.

CASE PRESENTATION

A 19-year-old male patient was admitted to our hospital for headache. Cranial magnetic resonance imaging revealed a mass of abnormal signal shadows in the prepontine cistern. The mass was surgically removed and the patient was consequently diagnosed with intracranial Rosai-Dorfman disease. Seven months later, pathological examination confirmed that the RDD had recurred. Next-generation sequencing found KRAS mutation in exon 4 (C.351A > C. P. K117n).

CONCLUSION

RDD of the CNS has no distinct clinical manifestations and imaging characteristics, and the final diagnosis should be based on the results of the pathological examination. Although RDD is not currently classified as a neoplastic disorder, some evidence of clonality has changed our understanding of it. Follow up examinations over a long period are necessary to determine the efficacy of treatment.

Craniocervical Rosai-Dorfman Disease presentation: Case report and review of literature

Rosai Dorfman Disease (RDD) is a benign histiocytic lymphoproliferative disease that has variable presentations. The concurrent presentation of RDD in the spinal cord and brain parenchyma is an extremely rare entity. Here, we report another case of a 24-year-old gentleman who presented with a tuberculum sellae and bilateral cavernous extra-axial tumors extending to the subtemporal lobe and was found to have craniocervical lesions. Axillary lymph node biopsy was done showing markedly dilated sinuses filled with large histiocytes and emperipolesis of numerous lymphocytes and plasma cells confirming the diagnosis of RDD. Because the definitive diagnosis of RDD is always pathological, the clinical presentation plays a major role in widening the margin of differential diagnosis. Finally, surgical intervention is the first option to treat RDD with relatively satisfactory follow-up outcomes, and other adjuvant therapies optimize the prognosis.

Rosai-Dorfman Disease: Case Series and Literature Review

Rosai-Dorfman Disease (RDD), also known as sinus histiocytosis with massive lymphadenopathy, is an uncommon histiocytic condition characterized by massive histopathological aggregation of CD1-a negative, CD68-positive, and S100-positive histiocytes. It was initially described by Destombes in 1965 under the term "adenitis with lipid excess." However, it is named after Rosai and Dorfman who reported further histopathological features of the disease in 1969. The diagnosis of this non-Langerhans cell histiocytosis can be challenging and requires high clinical suspicion. The diagnostic process usually involves imaging, tissue biopsies, and genetic testing as needed. In this case series, we are presenting three cases of rare disease. Case 2 had both nodal and extranodal forms, which makes this case rarer than cases 1 and 3, which present with extranodal lesions.

Subglottic Masses Revealing Rosai-Dorfman Disease

Rosai-Dorfman disease (RDD) is an uncommon lymphoproliferative disorder; RDD with oropharyngeal involvement is extremely rare, especially in adults. A 65-year-old woman with a complaint of progressive dyspnoea since 2016 presented with laryngeal involvement of RDD. A laryngoscopy examination revealed two solid, polypoid masses in the subglottic region, and a laryngeal biopsy concluded chronic inflammation without signs of malignancy. A second biopsy of axillary lymph nodes was performed, supporting the diagnosis of histiocytosis. The patient was treated with corticosteroids and then lost to follow-up. In 2019, she suffered from dyspnoea and a hoarse voice. Laryngoscopy examination showed a polypoid lesion causing airway obstruction at 70% and thickening of the lateral wall of the cavum. Physical examination found left axillary and submandibular adenopathy, and computed tomography revealed thickening of the supraglottic larynx narrowing the laryngeal pathway. Lymphadenectomy with immunohistochemical analysis revealed typical protein positive S-100 histiocytes and emperipolesis. The patient was treated with high doses of corticosteroids for six weeks then these were progressively decreased. The outcome was favourable; the laryngeal lesion disappeared after two weeks of treatment.

LEARNING POINTS

Rosai-Dorfman disease is a rare cause of lymphadenopathy in adults. Extranodal presentation of the disease is possible mainly in the head and the neck region.The diagnosis is based on histological examination with the presence of histiocytes, which are S-100 positive, CD68 positive, and CD1a negative immunohistochemistry.The outcome is usually good in asymptomatic forms of the disease with no critical organ involved. The surgical resection is appropriate to the localised symptomatic form of the disease while corticosteroids are indicated in disseminated RDD as a first-line therapy.Inspired by our case, rare localisation of Rosai-Dorfman disease (RDD), led to clinical and therapeutic issues. That is why a review of the literature must be undertaken, to share experiences.

Scattered Reddish-brown Nodules on the Head in an Elderly Man: A Quiz

Abstract is missing (Quiz)

Erdheim-Chester disease with Rosai-Dorfman-like lesions: treatment with methotrexate, anakinra and upadacitinib

Erdheim-Chester disease (ECD) is a non-Langerhans cell histiocytosis characterised by clonal expansion of histiocytes in various organs. These induce an inflammatory environment, which leads to damage of the affected areas. Recently, a new disease entity was proposed encompassing key features of ECD but also of Rosai-Dorfman-Destombes disease, another histiocytosis. Mitogen-activated protein kinase kinase 1 (MAP2K1) mutations seem to present a specific genetic lesion for this subtype.Here, we describe a case of this new disease entity with clinical, radiological and genetic findings compatible with ECD but histological findings compatible with Rosai-Dorfman-Destombes disease. In particular, there were intraabdominal and retroperitoneal lesions, which tested positive for a (c.167A>C; p.Q56P) mutation of the MAP2K1 gene. On histological examination, S100-positive, giant histiocytes with focal emperipolesis of haematological cells in addition to infiltration by lymphocytes and granulocytes were seen.As described for this rare variant of ECD, there was also bilateral testicular infiltration. We also describe a manifestation of oligoarthritis in this patient with ECD.The patient was treated with methotrexate and prednisolone. While radiological response to this regime was excellent, arthritis persisted. We added anakinra, which induced a response of the arthritis for more than a year. Due to treatment failure therapy was switched to upadacitinib, which induced a remission of the arthritis as well.This case adds a rare phenotype to an already rare presentation of ECD. The patient responded to immunosuppressive therapy.

The Impact of PET/CT on Paediatric Oncology

This review paper will discuss the use of positron emission tomography/computed tomography (PET/CT) in paediatric oncology. Functional imaging with PET/CT has proven useful to guide treatment by accurately staging disease and limiting unnecessary treatments by determining the metabolic response to treatment. ¹⁸F-Fluorodeoxyglucose (2-[¹⁸F]FDG) PET/CT is routinely used in patients with lymphoma. We highlight specific considerations in the paediatric population with lymphoma. The strengths and weaknesses for PET/CT tracers that compliment Meta-[¹²³I]iodobenzylguanidine ([¹²³I]mIBG) for the imaging of neuroblastoma are summarized. 2-[¹⁸F]FDG PET/CT has increasingly been used in the staging and evaluation of disease response in sarcomas. The current recommendations for the use of PET/CT in sarcomas are given and potential future developments and highlighted. 2-[¹⁸F]FDG PET/CT in combination with conventional imaging is currently the standard for disease evaluation in children with Langerhans-cell Histiocytosis (LCH) and the non-LCH disease spectrum. The common pitfalls of 2-[¹⁸F]FDG PET/CT in this setting are discussed.

Case report: Rosai-Dorfman disease with rare extranodal lesions in the pelvis, heart, liver and skin

Rosai-Dorfman disease (RDD), a rare form of non-Langerhans cell histiocytosis, can involve systemic extranodal lesions. Skin lesions are the most common, whereas intrapelvic, cardiac, and hepatic lesions are infrequent. The present study describes a 74-year-old woman with multiple extranodal lesions in the pelvis, heart, liver, and skin that were successfully treated with glucocorticoid therapy. She had experienced fever and persistent inflammation without cervical lymphadenopathy for several months and ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET) showed abnormal FDG uptake in the left cheek; cervical, axillary, inguinal lymph nodes; periatrium; and pelvis. She was diagnosed with RDD based on skin and pelvic biopsies. Although this was an atypical case without bilateral cervical lymphadenopathy, the FDG-PET detection of inflammatory lesions led to selection of suitable biopsy sites, and pathological examination led to a correct diagnosis. Findings in this patient indicate that RDD can present with an atypical distribution of infrequent extranodal lesions, with attention required to prevent a delayed diagnosis.

Extranodal Rosai-Dorfman disease: A rare mimicker of metastatic renal cell carcinoma

A 29-year-old female presented with the history of pain in the abdomen and a palpable lump in the right hypochondrium, lumbar, and the umbilical regions for the past 2 months. On evaluation with contrast-enhanced computed tomography (CECT) and positron emission tomography CT, she was found to have a heterogeneously enhancing mass entirely replacing the mid and the lower pole of the right kidney, the pelvis, and the upper ureter with loss of fat planes with the inferior vena cava, psoas muscle, and the hepatic flexure, along with pericardial deposits and soft tissue lesions at multiple paravertebral regions and the right thigh. Owing to a high suspicion of metastatic renal cell carcinoma (RCC), a right cytoreductive nephrectomy was performed. Histopathology revealed extranodal Rosai-Dorfman disease, which was mimicking a metastatic RCC on imaging. The patient was started on oral steroids to control the distant lesions and to prevent progression of the disease and is doing well at follow up.

Case report: BRAF-inhibitor therapy in BRAF-mutated primary CNS tumours including one case of BRAF-mutated Rosai-Dorfman disease

BRAF V600E oncogene mutations have been reported in multiple central nervous system (CNS) tumor types, and emerging evidence supports the use of targeted therapy in BRAF-mutated gliomas. BRAF oncogene mutations have been recently identified in Rosai-Dorfman disease (RDD)-a rare non-Langerhans cell histiocytosis. This series describes three patients from two neurosurgical centers in Ireland with BRAF V600E-mutated CNS tumors. The study participants include a 19-year-old male patient with ganglioglioma with anaplastic features, a 21-year-old male patient with CNS involvement of RDD, and a 28-year-old female patient with ganglioglioma with anaplastic features. Two patients received radiation with concurrent temozolomide before BRAF-targeted therapy. This case series describes clinical and radiological responses to BRAF-targeted therapy in BRAF V600E-mutated gliomas across multiple tumor grades and is only the second published report of response to targeted therapy in BRAF-mutated RDD. The durability of disease control with BRAF-targeted therapy was generally superior to that achieved with chemoradiation; one patient has experienced ongoing disease control for 5 years. The reported case of treatment response in BRAF-mutated RDD supports the strategy of genotyping and utilization of targeted therapy in this rare disease. The optimal sequencing of BRAF-targeted therapy in BRAF-mutated gliomas/glioneuronal tumors remains unclear, and further prospective studies are required to guide the use of genome-matched therapy in this patient population.

Case report: A rare case of Rosai-Dorfman-Destombes disease after the COVID-19 infection

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is known to cause immune dysregulation and, therefore, has varied and often rare presentations. Rosai-Dorfman-Destombes disease (RDD) is an unusual non-Langerhans cell (non-LC) histiocytosis presenting with massive lymphadenopathy and various systemic symptoms. A 55-year-old Asian-American woman with no significant medical history or recent use of new drugs initially presented with cervical lymphadenopathy and urticarial rash 1 week after receiving the COVID-19 messenger RNA (mRNA) vaccine (Moderna, mRNA-1273) against SARS-CoV-2. The biopsy of the skin rash was consistent with a drug reaction. Approximately 2 months later, she developed mild flu-like symptoms and was diagnosed with a COVID-19 infection. Her symptoms were mild and self-resolving. Approximately 3 months later, she developed a generalized patchy erythematous rash on the face and the body that gradually worsened; diffuse lymphadenopathy involving the bilateral cervical, axillary, and inguinal areas; and constitutional symptoms. Laboratory results were consistent with lymphopenia, anemia, and an elevated sedimentation rate. Supraclavicular lymph node biopsy showed Rosai-Dorfman disease with a marked polyclonal plasmacytosis. She was started on a tapering dose of corticosteroids and showed clinical improvements over the next few weeks. Herein, we present a rare case of a histiocytic disorder that developed after contracting the SARS-COV2 infection in the event of receiving a recent mRNA COVID vaccination.

Perforating Colitis Secondary to Immune Checkpoint Inhibitor Use in a Patient With Pericolonic Involvement by Rosai-Dorfman Disease

Recently, the use of immunotherapy has increased substantially for the treatment of several malignancies. It is associated with several gastrointestinal adverse events; however, severe complications such as intestinal perforation are rare. We present a 75-year-old man with metastatic melanoma, presented with profuse diarrhea and abdominal pain, after ipilimumab and nivolumab administration. Shortly after, he developed fulminant colitis and intestinal perforation and was found to have concurrent Rosai-Dorfman disease of pericolonic lymph nodes. With the increasing use of immunotherapy, reporting of serious adverse events and their mimics is essential. In addition, further studies are required to investigate whether an association exists between Rosai-Dorfman disease and immunotherapy.

Bone Marrow Infiltration in Rosai-Dorfman Disease

Rosai-Dorfman disease (RDD) is a rare and benign nonLangerhans cell histiocytosis. RDD commonly affects children and young adults typically presenting with massive, painless, and bilateral cervical lymphadenopathy. Extranodal involvement is present in about 40% of cases, and bone marrow infiltration is rare and unusual. RDD prognosis is usually good, however, involvement of bone marrow is associated with poor prognosis. We report a case of RDD with bone marrow involvement occurring in a 5-year-old female. She was admitted for asthenia, gingival bleeding, and diffuse bone pain without fever. Physical examination showed pallor, petechiae over the abdomen, painless and bilateral cervical lymphadenopathy, and several bony nodules, without splenomegaly or hepatomegaly. Cell blood count revealed microcytic hypochromic anemia with thrombocytopenia. Bone marrow aspiration showed infiltration by large histiocytes with hypochromatic nuclei and abundant vacuolated cytoplasm without emperipolesis. Biopsies of bone marrow, lymph node, and bone revealed immunohistochemical features of RDD: the histiocytes were positive for CD68 and S100 protein, but negative for CD1a. The patient initially received symptomatic treatment. One week after admission, she died of septic shock before the final establishment of RDD diagnosis. This case report highlights that bone marrow involvement in RDD is rare and associated with poor prognosis. We also aim to emphasize the obligation of bone marrow exploration in patients with RDD and presenting cytopenias in order to make an early diagnosis of bone marrow infiltration.

Case report: A new pathogenic variant of LRBA deficiency with a complex phenotype and Rosai-Dorfman disease

We reported a new pathogenic variant of LRBA deficiency with a complex phenotype-neonatal diabetes, very early-onset inflammatory bowel disease, and polyarthritis-who presented with lymph node enlargement. A case of Rosai-Dorfman's disease (RDD) was confirmed. The occurrence of an RDD lesion in LRBA-deficiency has never been reported so far.

Outcomes After Treatment With Cobimetinib in Patients With Rosai-Dorfman Disease Based on KRAS and MEK Alteration Status

Importance

Rosai-Dorfman disease (RDD) is a rare histiocytic neoplasm with recent studies showing alterations in the MAPK pathway, most commonly in the KRAS and MEK genes in about 40% of patients. Reports on the use of MEK-inhibitor therapy in RDD have been limited to small case studies. There are no approved treatments for this neoplasm, and therefore patients with RDD need efficacious treatments.

Objective

To study the outcomes after treatment with cobimetinib based on MAPK pathway alterations in patients with RDD.

Design, Setting, and Participants

This retrospective cohort study conducted at 2 tertiary care centers included patients with RDD who underwent treatment with cobimetinib between January 1, 2013, and December 1, 2021. Cobimetinib was administered at a dosage of 20 to 60 mg orally once daily as a single agent for 21 days in a 28-day cycle. Pathology was centrally reviewed. Response assessment was centrally conducted and was based on the established positron emission radiography response criteria used for clinical trials of targeted therapies in histiocytosis.

Main Outcomes and Measures

Main outcomes were overall response rate (ORR), progression-free survival (PFS), adverse events (AEs) of cobimetinib in the entire cohort, and ORRs and PFS based on MAPK pathway alterations in patients with RDD.

Results

A total of 16 patients (median [range] age at cobimetinib initiation, 57 [31-74] years; 11 [69%] women) were included in the study. The median follow-up duration was 19.0 months (95% CI, 8.4-27.8 months). The ORR was 63% (n = 10), including 5 complete responses and 5 partial responses. Somatic alterations in the KRAS or MEK genes were detected in 8 (50%) patients. Patients with KRAS or MEK alterations had significantly higher ORR (88% vs 38%; P = .03), deeper responses (complete responses among responders: 71% vs 0%; P = .002), and better PFS (at 1 year, 100% vs 29% were free from progression or death, respectively; P < .001) compared with those without such alterations. Grade 2 or higher AEs occurred in 12 (75%) patients, and 9 (56%) required dose reduction or temporary/permanent treatment discontinuation due to AEs.

Conclusions and Relevance

In this cohort study, treatment with cobimetinib was associated with positive outcomes in KRAS- or MEK-variant RDD. However, AEs requiring dose modifications were common.

68Ga-FAPI and 18F-FDG PET/CT Images of a Patient With Rosai-Dorfman Disease With Liver Involvement

ABSTRACT

Rosai-Dorfman disease is a rare non-Langerhans cell histiocytosis that is histopathologically characterized by the accumulation of CD68-positive and S100-positive histiocytes. The pathological changes are mostly discovered in lymph nodes. We report a case of Rosai-Dorfman disease with liver and bone marrow involvement. In this case, 18F-FDG PET/CT revealed FDG avidity in multiple lymph nodes, liver, and bone marrow. 68Ga-FAPI PET/CT showed higher uptake of 68Ga-FAPI than that of 18F-FDG in the same lesions. The findings of 68Ga-FAPI PET/CT in this patient highlighted the potential value of 68Ga-FAPI for staging in Rosai-Dorfman disease.

Challenges and positive impact of rare cancer caregiving: A mixed-methods study of caregivers of patients with Erdheim-Chester disease and other histiocytic neoplasms

BACKGROUND

The importance of deriving benefit and meaning has been identified among cancer caregivers, but this has yet to be examined in the context of rare cancers. We sought to characterize unmet needs and experiences of caregivers of patients with Erdheim-Chester disease (ECD) and other histiocytic neoplasms (HN) and to identify factors associated with finding benefit and meaning-making in providing care for patients with rare cancers.

METHODS

Caregivers of patients with ECD and other HN completed quantitative surveys. Linear univariable regression modeling examined associations between unmet needs, social and family support, and intolerance of uncertainty with benefit finding and meaning-making. A subset participated in qualitative interviews assessing experiences of rare cancer caregiving that were analyzed with applied thematic analysis (NCT039900428).

FINDINGS

Of caregivers (N = 92, M = 54 years old, 68% female) of patients with ECD (75%) and other HN (25%), 78% reported moderately or severely unmet support needs, most frequently informational (58%) and psychological/emotional (66%) needs. Caregivers with unmet informational, psychological/emotional, and social support needs, difficulty tolerating uncertainty, a longer duration of the patient's illness, lower social support, more family conflict, and higher anxiety and depression symptoms demonstrated less benefit finding and meaning-making (ps <.05). Qualitative interviews (N = 19) underscored information and support needs and the capacity to derive meaning from caregiving.

INTERPRETATION

Rare cancer caregivers report numerous unmet information and support needs, needs that arise from disease rarity itself and which are associated with diminished capacity for deriving benefit and meaning from caregiving. Findings highlight targets for interventions to improve support for caregivers with HN and other rare cancers.

FUNDING

NIH P30 CA008748 (PI: Craig Thompson, MD), NIH T32 CA009461 (H.M.; PI: Jamie Ostroff, PhD), Frame Family Fund (E.L.D.), Applebaum Foundation (E.L.D.).

Cervical Lymphadenopathy and Airway Masses in a Child

A previously healthy 12-year-old boy presented with a 3-month history of nasal obstruction, progressive dysphonia, recurrent deep neck abscesses, and tender, bulky cervical lymphadenopathy. What is your diagnosis?

Rosai–Dorfman disease of the central nervous system: A clinical, radiological, and prognostic study of 12 cases

Background

Rosai–Dorfman disease (RDD) is a rare benign non-Langerhans cell histiocytic proliferative disease. RDD with central nervous system (CNS) involvement (CNS-RDD) is extremely rare. Its etiology is unclear, and there are no consensus recommendations for its treatment. More studies are needed to elucidate the clinical and radiological manifestations and prognosis of CNS-RDD.

Methods

From January 2012 to June 2022, 12 patients with CNS-RDD (intracranial or spinal) were retrospectively evaluated, including collecting clinical data, imaging data, and pathological findings; summarizing imaging characteristics; and conducting follow-up studies on CND-RDD patient treatment and prognosis.

Results

Twelve CNS-RDD patients (nine male and three female patients, aged 12–67 years) were enrolled in this study. Nine patients represented convex and/or skull base RDD (eight with edema, six with lobulation and/or pseudopodium sign, four with multiple intracranial lesions), two patients had parenchymal RDD, and one patient had spinal cord subdural lesions. Symptoms of patients would vary according to the locations of the lesion, including but not limited to headaches, dizziness, seizures, cranial nerve dysfunction, and visual impairment. The immunohistochemistry of RDD showed positive expression of S100 and CD68 but not CD1a. Total resection (n = 7), subtotal resection (n = 3), partial resection (n = 1), and stereotaxic biopsy (n = 1) were achieved, respectively. A combination of chemotherapy plus steroid therapy was performed on two patients (relapsing case and residual lesion) and showed a remarkable effect.

Conclusion

CNS-RDD, as a rare disease, presents a significant diagnostic challenge for clinicians. Solitary CNS-RDD are easily misdiagnosed as meningioma. However, when the MRI imaging of the disease represents dura-based masses with significant edema, homogeneous enhancement, lobulation, and/or pseudopodium sign, we should consider it might be the CNS-RDD. Surgery is an important and effective therapy for CNS-RDD. Steroids and chemotherapy are safe and effective for the postoperative treatment of relapsing cases or residual lesions.

Rosai-Dorfman Disease between Proliferation and Neoplasia

Rosai-Dorfman disease (RDD) is a rare myeloproliferative disorder of histiocytes with a broad spectrum of clinical manifestations and peculiar morphologic features (accumulation of histiocytes with emperipolesis). Typically, the patient with RDD shows bilateral painless, massive cervical lymphadenopathy associated with B symptoms. Approximately 43% of patients presented with extranodal involvement. According to the 2016 revised histiocytosis classification, RDD belongs to the R group, including familial and sporadic form (classical nodal, extranodal, unclassified, or RDD associated with neoplasia or immune disease). Sporadic RDD is often self-limited. Most RDD needs only local therapies. Nevertheless, a small subpopulation of patients may be refractory to conventional therapy and die of the disease. Recent studies consider RDD a clonal neoplastic process, as approximately 1/3 of these patients harbor gene mutations involving the MAPK/ERK pathway, e.g., NRAS, KRAS, MAP2K1, and, rarely, the BRAF mutation. In addition to typical histiocytic markers (S100/fascin/CD68/CD163, etc.), recent studies show that the histiocytes in RDD also express BCL-1 and OCT2, which might be important in pathogenesis. Additionally, the heterozygous germline mutation involving the FAS gene TNFRSF6 is identified in some RDD patients with an autoimmune lymphoproliferative syndrome type Ia. SLC29A3 germline mutation is associated with familial or Faisalabad histiocytosis and H syndrome.

Strong Coexpression of Transcription Factors PU.1 and Oct-2 in Rosai-Dorfman Disease

OBJECTIVES

Rosai-Dorfman disease (RDD) is a rare disorder characterized by the accumulation of large S100 protein-positive histiocytes that typically exhibit emperipolesis. The recently reported expression of Oct-2 in RDD histiocytes led us to explore whether PU.1, a transcription factor that is required for monocyte and B-cell development, could similarly function as a diagnostic marker in RDD.

METHODS

We evaluated the expression of PU.1 and Oct-2 using immunohistochemistry in 19 patients diagnosed with RDD involving nodal, extranodal, and cutaneous sites.

RESULTS

Both PU.1 and Oct-2 were positive in all cases studied, with a strong intensity of staining in 84% of cases in which more than 50% of the lesional cells were positive. In three patients, both markers showed weak to moderate intensity of staining. Two patients had concomitant RDD and Langerhans cell histiocytosis in which PU.1 stained both types of histiocytes while Oct-2 stained only the RDD component.

CONCLUSIONS

PU.1 emerged as a robust marker with crisp nuclear staining in RDD histiocytes as well as in engulfed inflammatory cells. Strong coexpression of PU.1 and Oct-2 is a useful diagnostic marker in differentiating histiocytic/dendritic cell proliferations.

A unique case of isolated thoracic spinal Rosai-Dorfman disease related to IgG4

Rosai-Dorfman disease (RDD) is a rare benign histiocytosis usually characterized by massive cervical lymphadenopathy and systemic manifestations. Extranodal, especially spinal involvement, is extremely rare. Our case was deemed worthy of presentation because it was the first reported isolated case of spinal RDD related to IgG4 and mimicked meningioma clinically and radiologically. A case with an intradural extramedullary mass causing neurological compression findings in the thoracic spinal region and radiologically mimicking meningioma is presented. In the histomorphological examination of the resection material, polymorphonuclear leukocytes in the dura, histiocytes showing emperipolesis, an increase in collagenized fibrous connective tissue, and intense lymphoplasmacytic cell infiltration accompanied by obliterative phlebitis were observed. Immunohistochemically, the histiocytic cells were found to be S-100 protein, CD68, and CD163 positive and CD1a and langerin negative, and more than half of the plasma cells were immunoglobulin-G4 (IgG4) positive. Although rare, RDD or IgG4-related meningeal disease should be considered in the differential diagnosis of dural-based spinal masses that radiologically suggest meningioma. The pathologist should be aware that these two histopathological entities may coexist. To our knowledge, this is the first case of "isolated spinal RDD related to IgG4" reported in the literature.

Rosai-Dorfman disease mimicking gastrointestinal tuberculosis and fungal sinusitis: A case report

Every organ can be affected by Rosai-Dorfman disease, the most common being skin and soft tissue, bone and upper respiratory tract. Here we present a Rosai-Dorfman disease patient who manifested with multiple organ involvement. A 33-year-old male presented with multiple joint pain, diarrhea, a purulent nasal discharge and sinus pain. After having serials of investigations he was misdiagnosed as having tuberculosis and fungal sinusitis. Finally, cytology from lymph node aspiration suggested Rosai-Dorfman disease. The sino nasal presentation of Rosai-Dorfman disease can be misdiagnosed as fungal sinusitis and the gastrointestinal manifestation can mimic gastrointestinal tuberculosis. Diffuse joint involvement could also be an initial manifestation of Rosai-Dorfman disease.

Histiocytic Disorders of Childhood

Histiocytic disorders of childhood represent a wide spectrum of conditions that share the common histologic feature of activated or transformed "histiocytes." Langerhans cell histiocytosis (LCH) is the most common, with an incidence of approximately 5 per million children. LCH may be difficult to distinguish from more ubiquitous causes of skin rashes, bone pain, or fever. Current chemotherapy fails to cure more than 50% of children with multifocal disease, and treatment failure is associated with increased risks of long-term sequelae. Somatic activating mitogen-activated protein kinase (MAPK) pathway-activating mutations (most often BRAFV600E) have been identified in hematopoietic precursors in patients with LCH. Opportunities to improve outcomes with targeted therapies are under investigation. Juvenile xanthogranuloma (JXG) and Rosai-Dorfman disease (RDD) are less common than LCH and are distinguished by specific histologic and clinical features. Recurrent MAPK pathway gene mutations are also identified in JXG and RDD. In many cases, these conditions spontaneously resolve, but disseminated disease can be fatal. Although there has been historic debate regarding the nature of these conditions as inflammatory versus neoplastic, LCH, JXG, and RDD are now considered myeloid neoplastic disorders. In contrast, hemophagocytic lymphohistiocytosis (HLH) is clearly a disorder of immune dysregulation. HLH is characterized by extreme immune activation driven by hyperactivated T cells. HLH arises in approximately 1 child per million and is nearly universally fatal without prompt recognition and immune suppression. Outcomes of treated children are poor, with approximately 60% survival. Emapalumab, which targets interferon-γ signaling, was recently approved for patients with recurrent or refractory HLH, and additional cytokine-directed therapies are under investigation.

Rosai-Dorfman Disease Presenting as Massive Mediastinal Lymphadenopathy in an Elderly Man

We present a patient case of a 73-year-old man with new-onset substernal chest pain and B symptoms, found on computed tomography imaging to have massive mediastinal lymphadenopathy of more than 6 cm. Positron emission tomography imaging revealed fluorodeoxyglucose-avid nodes further extending to the axillary, abdominal, and inguinal regions. After a broad patient work-up for infectious, malignant, and rheumatic causes, he was ultimately diagnosed with Rosai-Dorfman disease, a rare histiocytic neoplasm, by excisional lymph node biopsy.

Treatment-Refractory Nodular Scleritis

A 59-year-old woman with a 5-year history of intermittent bilateral uveitis and scleritis presented with painful left uveitis and an episcleral nodule shown to be a uveal-episcleral lesion on ultrasound biomicroscopy. Biopsy of a nasal sinus mass 3 years earlier showed a histiocytic infiltrate with emperipolesis, consistent with Rosai-Dorfman-Destombes disease. What would you do next?

A lesion of the patella: An unexpected location of Rosai-Dorfman disease: A case report

Introduction

Primary osseous Rosai-Dorfman disease (RDD) is a rare and benign disease that can pose diagnosis challenges.

Presentation of the case

We report the case of a 29-year-old woman who presented with pain in her left patellar region for the past 6 months with no other clinical sign especially no lymphadenopathy associated. A surgical excision was done. Histopathology confirmed the diagnosis of a primary RDD patellar disease. The patient was followed up for 2 months without any recurrence. The aim of this study was to present a rare case of RDD in a patellar location and to review clinicopathological features, therapeutic modalities, evolutionary aspects and prognosis of a primary patellar RDD.

Discussion and conclusion

The diagnosis of a primary osseous RDD without associated lymphadenopathy should be kept in mind when a sclero-lytic lesion is found. Excision of the lesion is the gold standard of the treatment.

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Isolated patellar RDD is rare.

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The diagnosis is made on histopathological examination of resected tissue

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Prognosis is good and disease course is not aggressive

Radiological features of Rosai-Dorfman disease: case series and review of the literature

AIM

To improve the accuracy of diagnosis of Rosai-Dorfman disease (RDD) by summarising the computed tomography (CT) and magnetic resonance imaging (MRI) characteristics.

MATERIALS AND METHODS

The clinical manifestations, imaging findings, and pathological characteristics of 14 patients with histopathologically confirmed RDD were analysed retrospectively and a literature review was undertaken.

RESULTS

Of the 14 patients, nine had multiple lesions and five had single lesions. Eight patients had extranodal lesions, while six had mixed-type lesions. In patients with head and neck lesions, plain CT/MRI revealed irregularly shaped, well-defined, homogeneous, and mainly progressive lesions, with marked homogeneous enhancement on multiphasic contrast-enhanced imaging. One patient had dural lesions, one of which iso-intense to grey matter, with patchy hypo-intensity on T2-weighted imaging, meningeal tail signs, and characteristic crabfoot-like enhancement. Three patients with skeletal system involvement exhibited osteolytic bone destruction without sclerosis at the edges, associated soft-tissue masses, or periosteal reactions. Two patients had well-defined subcutaneous lesions, inhomogeneous density, and progressive parenchymal enhancement on contrast-enhanced CT. One patient had multiple intestinal lesions with inhomogeneous nodular thickening of the blind ascending colon and ileum, with marked and progressive enhancement.

CONCLUSION

RDD involvement is mainly multifocal, primarily in the head and neck regions. Plain CT/MRI revealed well-defined, irregularly shaped lesions with homogeneous density/signal, with marked and progressive enhancement on multiphasic contrast-enhanced imaging; however, histopathology is still required to confirm the diagnosis of RDD.

Dramatic Efficacy of Interferon and Vemurafenib on Psychiatric Symptoms Revealing BRAFV600E -Mutated Erdheim-Chester Disease: A Case Report

Erdheim–Chester disease (ECD) is a rare condition with underestimated neurological involvement. Mild psychiatric symptoms such as mood swings have been rarely described in the clinical spectrum of neuro-ECD. We here describe the first patient with psychiatric manifestations of delirium revealing ECD with neurological involvement with favorable evolution under interferon followed by BRAF inhibitor monotherapy. An 81-year-old woman was referred to the hospital because of delirium and severe cognitive impairment associated with a cerebellar syndrome. Brain magnetic resonance imaging showed “FLAIR-changes” lesions in the pons and upper cerebellum peduncles. Blood and cerebrospinal fluid (CSF) analyses showed normal results except for an elevated neopterin level in the CSF. Whole-body CT scan (¹⁸FDG-PET) showed peri-nephric fat infiltration and aorta adventitia sheathing with radiotracer uptake in the pons, vessels, peri-nephric fat, and bone lesions, which was characteristic of ECD. The diagnosis was confirmed on perirenal tissue biopsy, which also showed a BRAF^V600E mutation. Treatment with interferon resulted in the resolution of delirium, and treatment with BRAF inhibitor subsequently resulted in a partial remission of all active sites. This case highlights that delirium can be the first manifestation of neurodegenerative ECD. ECD should be screened in unexplained psychiatric features as interferon and targeted therapy appear to be effective in this situation.

Localized retroperitoneal Rosai-Dorfman-Destombes disease as a cause of fever of unknown origin in adults. Case report and review of the literature

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The localized abdominal RDD could be a possible cause of FUO.

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RDD should be considered in the differential diagnosis of localized retroperitoneal mass and FUO.

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FDG-PET/CT is a useful diagnostic tool for initial diagnosis, staging, and follow-up.

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In localized RDD, the surgery can be a definitive treatment.

Malignant histiocytosis associated with mediastinal germ cell tumor: A case report

BACKGROUND

Germ cell tumors (GCTs) account for 2% of human malignancies but are the most common malignant tumors among males aged 15-35. Since 1983, an association between mediastinal GCT (MGCT) and hematologic malignancies has been recognized.

CASE SUMMARY

We report a case in which malignant histiocytosis was associated with mediastinal GCTs. The clinical data of a male patient with MGCT admitted to Beijing Children's Hospital were collected retrospectively. The patient was first diagnosed according to imaging and pathological features as having MGCT, and was treated with surgery and chemotherapy. One year after stopping chemotherapy, imaging showed metastases in the right supraclavicular, mediastinum, hilar region and retroperitoneal lymph node, right pleura, right lung, and right para-cardiac margin. Pathological diagnosis of the liver nodular and hilar lymph nodes included systemic juvenile xanthogranuloma and Rosai-Dorfman lesions with malignant transformation (i.e., morphological characteristics and immunophenotype of histiocytic sarcoma). Following diagnosis, the patient accepted chemotherapy with vindesine, cytarabine and dexamethasone. Positron emission tomography–computed tomography showed partial remission. The patient was followed-up for 10 mo after the diagnosis of malignant histiocytosis, and no sign of progression or relapse was observed.

CONCLUSION

Physicians should recognize the possibility of hematologic malignancies being associated with MGCT. Suitable sites should be selected for pathological examination.

Xanthogranulomatous orchitis: A rare case of testicular mass

Xanthogranulomatous orchitis is a rare non-malignant condition. This study reports a new case of xanthogranulomatous orchitis in a 77-year-old male, who presented with acute right scrotal mass. Ultrasound and computed tomography showed a heterogenous lesion involving the testis, with a loculated collection in the overlying scrotal wall. Scrotal exploration revealed an abscess involving the scrotal skin, with hard mass involving the testis, with histological evidence of infiltration and replacement of most testicular parenchyma. This case highlights this important consideration for xanthogranulomatous orchitis in the differential of testicular mass, particularly when associated with a purulent collection.

Section headings

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Inflammation and Infection

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General Urology

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Xanthogranulomatous orchitis (XGO) is a rare inflammatory condition, limited to 26 case reports within published literature.

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XGO can be difficult to differentiate from a testicular neoplasm and is usually treated with orchidectomy.

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This case highlights important inflammatory and infectious differentials for XGO, and how their treatment would differ.

Rosai-Dorfman Disease of the Spine: A Case Report of a Rare Disease and Review of the Literature

Rosai-Dorfman disease (also known as sinus histiocytosis with massive lymphadenopathy or Rosai-Dorfman-Destombes disease) is a rare reactive histiocytic disease, classically involving the lymph nodes of the neck, but it can also occur in extranodal sites. Isolated spinal involvement is rare but important to identify as it can mimic malignancy with males being affected more than females. We present a case of a 52-year-old female patient who had breast cancer and was admitted with long-standing anal and sacral pain. The MRI lumbar spine showed a mass concerning for metastasis. CT-guided biopsy results showed sheets of histiocyte-like cells, some of which were positive with S100 and showed emperipolesis along with plasma cells, lymphocytes, and neutrophils. Features were in keeping with Rosai-Dorfman syndrome. The patient responded to steroids. The familiarity with this entity saved the patient from going through the agony of this being considered a metastasis of her primary malignancy.

Case report of H-syndrome with a review from a rheumatological perspective

A woman in her 20s, symptomatic since the age of 4 with short stature, hearing loss, skin hyperpigmentation and induration over the medial aspect of the thigh, hypertrichosis, histiocytes on biopsy, lymphadenopathy, dilated scleral vessels, pancreatic exocrine deficiency, pericardial thickening, swelling of the eyelids and resistant retroperitoneal fibrosis. Whole-genome sequencing showed a mutation in SLC29A3, confirming 'H'-syndrome. She is on steroids and methotrexate. This case highlights the rheumatological mimics of this rare disorder.

A Report of Rosai–Dorfman Disease in an Adolescent

Rosai–Dorfman disease (RDD) is a rare disease of unknown cause. It is a benign self-limiting condition characterized by the accumulation of activated histiocytes in the sinusoids of lymph nodes and/or extranodal tissues. Massive cervical lymphadenopathy as the initial manifestation tends to raise the initial odds in favour of a lymphoma, and thus reducing the threshold to performing a simple biopsy cannot be overestimated. Herein, we report a 13-year-old adolescent who presented with a progressive posterior left-sided neck swelling. Our diagnosis of RDD was established by demonstrating emperipolesis in histology and S100 positivity in immunohistochemistry as stated in the literature. Although the condition is known to be self-limiting, evidence from the literature and our case management shows that medical therapy can hasten remission in pediatric cases.

Cyclin D1 expression and molecular genetic findings in periocular histiocytoses and neoplasms of macrophage-dendritic cell lineage

PURPOSE

Frequent activating mutations in the mitogen-activated protein kinase (MAPK) pathway genes have been identified in histiocytoses. MAPK signaling consistently upregulates Cyclin D1. The goal of this study was to determine whether Cyclin D1 expression by immunohistochemistry is a useful diagnostic marker for periocular histiocytoses and to further characterize their genetic basis.

DESIGN

Retrospective observational case series.

METHODS

Pathology records were searched for all patients with histiocytoses diagnosed between 1995-2020. Eleven histiocyte-rich inflammatory lesions and 10 xanthelasma served as controls. Cyclin D1 immunohistochemistry was performed on all tissues. A subset of histiocytoses was evaluated by next-generation sequencing (NGS) and droplet digital PCR (ddPCR).

RESULTS

There were 36 patients, 15 (42%) males and 21 (58%) females, with histiocytoses: 9 (25%) juvenile xanthogranuloma, 8 (22%) adult-onset asthma and periocular xanthogranuloma, 7 (19%) Langerhans cell histiocytosis, 5 (14%) Rosai-Dorfman disease, 5 (14%) xanthogranuloma not otherwise specified, 1 (3%) Erdheim-Chester disease, and 1 (3%) histiocytic sarcoma. Moderate-to-strong nuclear Cyclin D1 expression was present in ≥50% of lesional cells in histiocytoses (23/36, 64%), significantly more when compared to histiocyte-rich inflammatory lesions (0/11, 0%, P<.001) and xanthelasma (0/10, 0%, P<.001). Cyclin D1 was expressed in <10% of lesional cells in all 11 histiocyte-rich inflammatory lesions (P<.001) and all 10 xanthelasma lesions (P<.001). MAPK pathway gene mutations were detected in 12 of 14 (86%) histiocytoses successfully assayed by NGS and/or ddPCR.

CONCLUSIONS

Our study confirms that the Cyclin D1 immunohistochemical stain is a useful diagnostic marker for periocular histiocytoses, correlating with underlying mutations in MAPK pathway genes.

Neurology and the histiocytoses: a case of Rosai-Dorfman-Destombes disease

The histiocytoses are a group of rare disorders characterised by the accumulation of neoplastic or non-neoplastic activated histiocytes in various tissues. Phenotypes vary widely from cutaneous lesions or lymphadenopathy that regress spontaneously to disseminated disease with poor prognosis. Neurological symptoms can be a presenting feature or appear during the course of disease. We present a challenging diagnostic and management case of Rosai-Dorfman-Destombes disease in a 48-year-old woman with a relapsing, partially steroid-responsive syndrome comprising patchy, non-length-dependent radiculoneuropathy with diffuse pachymeningitis and widespread systemic disease, and recent dramatic response to novel mitogen-activated kinase pathway inhibition. We discuss the clinical characteristics, diagnosis, recent breakthroughs in pathogenesis and emerging treatment options for Rosai-Dorfman disease and for the histiocytoses with neurological sequelae, including Langerhans cell histiocytosis and Erdheim-Chester disease.

A 54-Year-Old Woman with Cutaneous Nodules

A 54-Year-Old Woman with Cutaneous NodulesA 54-year-old woman presented with chronic cutaneous nodules and plaques. How do you approach the evaluation, and what is the diagnosis?

Differential diagnosis in Rosai-Dorfman disease: A rare case of isolated hepatic presentation mimicking a metastatic tumor with positive 18-FDG uptake

Rosai-Dorfman disease (RDD) is also called sinus histiocytosis with massive lymphadenopathy, and it is caused by a histiocytic disorder with unclear etiology. It usually involves cervical lymph nodes, but it may also present with extranodal involvement. We report a rare condition of isolated hepatic RDD without nodal involvement, clinically manifested with three-month abdominal pain and tenderness of the right hypochondrium. CT- and PET-CT scans were compatible with a secondary lesion from an unknown primary tumor. Therefore, the patient underwent an atypical liver resection. Immunohistochemistry and histological results were compatible with a diagnosis of RDD. RDD is characterized by phenomena of emperipolesis, histiocytic proliferation and positive immunostaining for CD14, CD68 and S-100 protein. Cases of isolated gastrointestinal localization of RDD are particularly rare, especially in the liver. Instrumental exams might confuse RDD with other malignancies. RDD is a rare entity, which might be misdiagnosed using PET-CT due to its similarities with malignant tumors. An accurate multidisciplinary approach may help to clear diagnostic clues of this uncommon disease.