Dendritic cell neoplasms: an overview

Virus-Host Interactions in Foot-and-Mouth Disease Virus Infection

Foot-and-mouth disease (FMD) is a highly contagious disease of cloven-hoofed animals, which has been regarded as a persistent challenge for the livestock industry in many countries. Foot-and-mouth disease virus (FMDV) is the etiological agent of FMD that can spread rapidly by direct and indirect transmission. FMDV is internalized into host cell by the interaction between FMDV capsid proteins and cellular receptors. When the virus invades into the cells, the host antiviral system is quickly activated to suppress the replication of the virus and remove the virus. To retain fitness and host adaptation, various viruses have evolved multiple elegant strategies to manipulate host machine and circumvent the host antiviral responses. Therefore, identification of virus-host interactions is critical for understanding the host defense against virus infections and the pathogenesis of the viral infectious diseases. This review elaborates on the virus-host interactions during FMDV infection to summarize the pathogenic mechanisms of FMD, and we hope it can provide insights for designing effective vaccines or drugs to prevent and control the spread of FMD and other diseases caused by picornaviruses.

[Extramammary myofibroblastoma affecting the pelvic region: a case report]

Un myofibroblastome de type mammaire est une tumeur molle rare; les myofibroblastomes extramammaires sont particulièrement rare. Un homme de 78 ans s'est présenté en consultation pour des douleurs pelviennes soulagées par la défécation ou les urines. Le toucher rectal retrouve une masse en avant de la paroi rectale antérieure. L'imagerie par résonance magnétique (IRM) montre une masse de 10 x 6 x 8cm, bien circonscrite et hétérogène, située en arrière de la vessie qu'elle refoule vers l'avant, en avant du recto-sigmoïde. L'immunohistochimie montre des cellules tumorales co-exprimant CD34 et la desmine de façon diffuse, expression de Rb dans la majorité des cellules, expression des récepteurs aux œstrogènes, expression intense et diffuse de la P16, un index de prolifération avec le ki67 estimé à 25%. Il n'y a pas eu de récidive après 8 mois de radiothérapie d'induction suivie de chirurgie. Un myofibroblastome de type mammaire est une tumeur rare et bénigne. La récidive n'est quasiment pas observée après traitement local. Ce cas permet de mettre en avance la possibilité d'utiliser la radiothérapie afin de faciliter la chirurgie.

U-DCS: characterization of the first permanent human dendritic sarcoma cell line

A dendritic cell sarcoma cell line, U-DCS, was established from a dendritic cell sarcoma in a 53-year-old Caucasian male patient. Since its establishment, U-DCS has maintained stable phenotypic characteristics in vitro and has a doubling time of approximately 2 days under standard culture conditions. U-DCS is growing with typical dendritic cell morphology in tissue and expresses the dendritic cell sarcoma immunophenotypic markers S100 protein, MHCI, MHCII, and vimentin. Expression analysis revealed transcripts for the toll-like receptors TLR3, -4, -9 and DDX58 (RIG-I), but not for TLR2. U-DCS shows functional features of dendritic cells with the ability of phagocytosis and antigen-specific T cell stimulation. Karyotype-, CGH-, and mFISH analysis point to a chromosomal instability and a hypotetraploid karyotype with approximately 130 chromosomes. U-DCS is the first immortalized human dendritic cell sarcoma cell line and has some morphological and functional features of dendritic cells without dependency on growth factors.

Leukemic Phase of Histiocytic Sarcoma of the Digestive System: A Rare Manifestation of a Rare Disease

Histiocytic sarcoma (HS) is a rare, malignant, and aggressive subtype of histiocytosis. We present an unusual case of aggressive HS presenting in the gastrointestinal tract and gallbladder that progressed after several lines of chemotherapy with a leukemic phase. We review the clinical, pathological, and molecular characteristics of HS in this case and review the literature on HS involving the digestive system as well as on overt leukemic phase of this disease. HS is often diagnosed at an advanced stage, and mortality is high. We discuss the therapeutic approach to patients with HS. We highlight the role of overexpression and somatic alterations in the RAF-MEK-ERK pathway in the pathogenesis of HS and discuss potential targeted approaches to treat these rare tumors.

18F-FDG PET/CT in Follicular Dendritic Cell Sarcoma With Paraneoplastic Pemphigus as the First Manifestation

A 48-year-old woman presented with refractory oral ulcers and skin rashes on the palms and trunk, diagnosed as paraneoplastic pemphigus. The chest x-ray revealed a mass in the right lower chest, and the F-FDG PET/CT scan showed the lesion in the right anterior-inferior mediastinum with intense F-FDG uptake, accompanied by right parasternal adenopathy and pleural effusion. The surgical pathology proved a follicular dendritic cell sarcoma, with right parasternal lymph node metastasis.

Follicular dendritic cell sarcoma in the right chest wall: A case report

RATIONALE

Follicular dendritic cell sarcoma (FDCS) is a rare malignant tumor that originates from germinal center follicular dendritic cells, and can occur at both nodal and extranodal sites. There are very few described cases of FDCS arising in the chest wall.

PATIENT CONCERNS

A 44-year-old male patient presented with a history of right chest wall pain for 5 months.

DIAGNOSES

Positron emission tomography/computed tomography showed a significant increase in F-fluorodeoxyglucose uptake and multiple small axillary lymph nodes without hypermetabolic lesions. Immunohistochemistry results of a core-needle biopsy indicated FDCS, which was consistent with the postoperative pathological examination.

INTERVENTIONS

The patient underwent tumor resection with lymphadenectomy of level I axillary nodes. No metastasis in the lymph nodes was observed in the postoperative pathological examination. The patient did not accept chemotherapy or radiotherapy.

OUTCOMES

After 18 months, the patient remains in good condition with no evidence of disease recurrence.

LESSONS

This report highlights a rare case of a FDCS arising in the chest wall. Accurate clinical diagnosis and staging of this rare malignant sarcoma is essential for the developmnt of effective treatment strategies. Preoperative F-fluorodeoxyglucose positron emission tomography/computed tomography scanning combined with core-needle biopsy could provide differentiation between benign and malignant tumors, as well as lymph node involvement and metastatic status.

Interdigitating dendritic cell sarcoma of the spleen with hepatic failure after chemotherapy: A case report

RATIONALE

Interdigitating dendritic cell sarcoma (IDCS) is an extremely rare disease originating from dendritic cells (DCs). There are few cases report interdigitating dendritic cell sarcoma of spleen along with their pathological characteristics and treatment.

PATIENT CONCERNS

Here we report a case of IDCS in 53-year-old female who presented spleen enlargement and thrombocytopenia.

DIAGNOSES

The patient underwent surgical resection of spleen, and the pathology confirmed IDCS.

INTERVENTIONS

She received surgical resection of spleen and one cycle of chemotherapy (ABVD with ifosfamide and oxaliplatin) after surgery.

OUTCOMES

She died of severe hepatic failure caused by chemotherapy.

DISCUSSION

IDCS is a rare disease with insufficient treatment guidelines. We adopted chemotherapy of ABVD with ifosfamide and oxaliplatin which showed no improvement but led to life-threatening liver damage.

TUBB1 dysfunction in inherited thrombocytopenia causes genome instability

Inherited thrombocytopenia is a genetically heterogeneous disease characterized by varying degrees of thrombocytopenia and risk of haematological malignancy, and the genetic cause of many cases remains unknown. We performed whole-exome sequencing of a family with thrombocytopenia and myeloid malignancy and identified a novel TUBB1 variant, T149P. Screening of other thrombocytopenia pedigrees identified another TUBB1 variant, R251H. TUBB1 encodes the tubulin β-1 chain, a major component of microtubules abundant in megakaryocytes. Variant TUBB1 disrupted the normal assembly of microtubules and impaired proplatelet formation in vitro. In addition, DNA damage response was severely attenuated by loss of TUBB1. We found that the nuclear accumulation of p53 (also termed TP53) and the expression of pro-apoptotic genes triggered by genotoxic stress were blocked in TUBB1-deficient cells and, accordingly, apoptosis after DNA damage was diminished by knockdown of TUBB1. Thus, we have demonstrated that microtubule dysfunction confers resistance to apoptosis, even in DNA damage-accumulated cells, which explains genome instability in the affected individuals. These studies will lead us to a better understanding of how microtubule dysfunction can contribute to the accumulation of DNA damage, genetic instability and leukaemogenesis.

Role of Adjuvant Chemotherapy in Extranodal Follicular Dendritic Cell Sarcoma

Extranodal follicular dendritic cell sarcomas (FDCSs) are an uncommon entity, commonly misdiagnosed because of the morphologic similarities with other neoplasias. Previously, FDCSs were not considered a differential diagnosis because of the limited use of immunohistochemistry. Surgical excision is the treatment of choice for localized FDCS. The role of chemotherapy has not been determined for this rare disease. We report 2 cases of metastatic extranodal intra-abdominal FDCS, initially misdiagnosed as gastrointestinal stromal tumor, their clinicopathological features, literature review, and the role of adjuvant chemotherapy.

Profiles of genomic alterations in primary esophageal follicular dendritic cell sarcoma: A case report

RATIONALE

Follicular dendritic cell (FDC) sarcoma is a rare tumor with FDC differentiation that typically arises within lymph nodes but can also occur extranodally. To date, the primary esophageal FDC sarcoma has not been reported in the English literature.

PATIENT CONCERNS

We described a 67-year-old female who foremostly presented with dysphagia, and the patient was readmitted due to a dry cough and pain of his right shoulder 2 years after initial treatment.

DIAGNOSES

Primary esophageal FDC sarcoma with the right superior mediastinal lymph node metastasis.

INTERVENTIONS

The esophageal tumor was removed by endoscopic submucosal dissection at the first hospitalization. At the second hospitalization 2 years after the initial visit, the tracheal stent loaded with (125) iodine radioactive seeds was placed. The profiles of genetic variations and immunotherapeutic biomarkers were also explored by next-generation sequencing protocol from the patient's blood, esophageal primary, and mediastinal metastatic tumor samples.

OUTCOMES

The patient's symptom transitorily relieved, but she gave up further treatment and died 2 months after the tracheal stent was placed. As for the genomic alterations, we found 9 gene mutations in all the samples, including checkpoint kinase 2(CHEK2), FAT atypical cadherin 1 (FAT1), tumor protein 53 (TP53), DPYD, ERBB2 interacting protein (ERBB2IP), FBXW7, KMT2D, PPP2R1A, TSC2, whereas amplification of MYC was only in the metastatic example. The analysis of clonal evolution and phylogenetic tree showed the propagation and replay of polyclonal esophageal FDC sarcoma. At the same time, the detection of biomarkers for immunotherapy revealed microsatellite stable and mismatch repair-proficient (pMMR), which predicted a relatively poor anti-programmed death (PD-1)/programmed death ligand (PD-L1) immunotherapy outcome. On the contrary, the tumor mutational burdens were 10 mutations per 1 million bases in both the primary and metastatic tumor sample, which ranked the top 23.3% in solid tumors mutational burdens database of Geneseeq and might be a good predictor of the efficacy of anti-PD-1/PD-L1 immunotherapy.

LESSONS

To the best of our knowledge, this case report announced the first case of extranodal primary esophageal FDC sarcoma in the world, and firstly revealed its unique genetic alterations profiles, which might contribute to further in-depth study of this rare disease.

Interdigitating dendritic cell sarcoma located in the groin: a case report and literature review

Interdigitating dendritic cell sarcoma (IDCS) is an extremely rare subtype of dendritic cell neoplasms, and current knowledge on this tumor is limited. We herein report a case of an IDCS in a 64-year-old man who presented with a right inguinal mass combined with extensive retroperitoneal, pulmonary, hepatic, renal, and bone marrow infiltration. Because of the advanced stage of the disease, we performed five cycles of chemotherapy, including cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP); doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD); and ABVD combined with cisplatin, and one cycle of radiotherapy. The patient’s inguinal mass became smaller during the treatment, but there was no change in the extent of infiltration at the other sites. The patient died 8 months after the initial diagnosis. We also herein review the etiology, diagnosis, differential diagnosis, treatment, and prognosis of IDCS, and analyze the characteristics of IDCS in Chinese patients.

Follicular Dendritic Cells of Lymph Nodes as Human Immunodeficiency Virus/Simian Immunodeficiency Virus Reservoirs and Insights on Cervical Lymph Node

A hallmark feature of follicular dendritic cells (FDCs) within the lymph nodes (LNs) is their ability to retain antigens and virions for a prolonged duration. FDCs in the cervical lymph nodes (CLNs) are particularly relevant in elucidating human immunodeficiency virus (HIV)-1 infection within the cerebrospinal fluid (CSF) draining LNs of the central nervous system. The FDC viral reservoir in both peripheral LN and CLN, like the other HIV reservoirs, contribute to both low-level viremia and viral resurgence upon cessation or failure of combined antiretroviral therapy (cART). Besides prolonged virion retention on FDCs in LNs and CLNs, the suboptimal penetration of cART at these anatomical sites is another factor contributing to establishing and maintaining this viral reservoir. Unlike the FDCs within the peripheral LNs, the CLN FDCs have only recently garnered attention. This interest in CLN FDCs has been driven by detailed characterization of the meningeal lymphatic system. As the CSF drains through the meningeal lymphatics and nasal lymphatics via the cribriform plate, CLN FDCs may acquire HIV after capturing them from T cells, antigen-presenting cells, or cell-free virions. In addition, CD4+ T follicular helper cells within the CLNs are productively infected as a result of acquiring the virus from the FDCs. In this review, we outline the underlying mechanisms of viral accumulation on CLN FDCs and its potential impact on viral resurgence or achieving a cure for HIV infection.

Dysfunction of antigen processing and presentation by dendritic cells in cancer

The ability to mount an effective anti-tumor immune response requires coordinate control of CD4 T cell and CD8 T cell function by antigen presenting cells (APCs). Unfortunately, tumors create an immunosuppressive microenvironment that helps protect tumor cells from immune recognition. In many cases this defect can be traced back to a failure of APCs (most importantly dendritic cells (DCs)) to recognize, process, and present tumor antigens to T cells. In this review, we will summarize work addressing the role of different DC subsets in anti-tumor immunity and the various mechanisms used by tumor cells to suppress the ability of APCs to stimulate potent anti-tumor T cell responses.

Intraabdominal Follicular Dendritic Cell Sarcoma: A Report of Three Cases and Review of the Literature

Follicular dendritic cell sarcoma (FDCS) is a rare neoplasm that originates from follicular dendritic cells in lymphoid follicles. FDCS has been increasingly reported in recent years. However, data on FDCS are mostly based on single case reports or case series and its natural history and standard treatment are not clear. To increase the understanding of this rare disease, we report our experience of three cases of FDCS with an analysis of the morphological and immunophenotypic characteristics, clinical course, treatment options and response to treatment. In addition, we reviewed the literature on FDCS.

Characteristics, management, and outcomes of patients with follicular dendritic cell sarcoma

Dendritic cell sarcomas are rare tumours of antigen presenting cells. Data regarding their biology, management and outcomes are sparse. We analysed 66 patients with follicular dendritic cell sarcoma (FDCS). Six patients also had Castleman disease, 9 had another malignancy and 13 had an autoimmune disease. Fifty-four per cent of patients presented with localized disease and 46% with systemic involvement. The median progression-free (PFS) and overall survival (OS) following frontline therapy was 21 and 50 months, respectively. Survival outcomes were significantly inferior in patients with extranodal, bulky or intra-abdominal disease at presentation. Stage was not associated with survival. Management approaches were heterogeneous. Patients who underwent an upfront gross total resection (GTR) experienced better PFS and OS (both P < 0·0001). In patients who underwent a GTR, consolidative radiotherapy was associated with improved local control (P = 0·03), PFS (P = 0·04) and OS (P = 0·05). In patients with measureable disease, gemcitabine with a taxane yielded an overall response rate of 80%. The pattern of relapse was predominantly locoregional. Salvage rates after recurrence were poor. Studies are underway at our institution to define the genomic profile in FDCS and identify potential novel therapeutic targets.

Clinicopathological Profile and Outcomes of Follicular Dendritic Cell Sarcoma of the Head and Neck Region - A Study of 10 Cases with Literature Review

INTRODUCTION

Follicular Dendritic Cell Sarcomas (FDCS) are rare disorders of the lymph node and soft tissues. Accurate characterization of these neoplasms is important in planning optimal treatment given its potential for recurrence and metastasis.

AIM

To analyse the clinicopathological profile and outcomes of a series of 10 cases of follicular dendritic cell sarcoma arising in the head and neck region diagnosed at our regional cancer centre.

MATERIALS AND METHODS

A series of 10 cases of FDCS of the head and neck region from the hospital registry of head and neck cancers diagnosed between 2007 and 2013 were collected and analysed retrospectively. Clinical details, pathologic features, immuno-phenotypic profile, treatment approach and outcomes over a period of 5 years were noted. The Recurrence Free Survivals (RFS) of all the patients were recorded.

RESULTS

The median age of the patients was 57 years and the mean age was 50.9 years. Male: female ratio was 7:3. In eight of the 10 patients, the tumours were located in the tonsils. All the tumour cells showed diffuse cytoplasmic CD21 and CD23 positivity by IHC. All the 10 cases underwent surgical excision of the tumour and three cases underwent additional neck dissection for cervical lymph node enlargement. All the patients with high grade tumours were uniformly managed with Tri-modality treatment (Surgery followed by radiotherapy and chemotherapy). The overall recurrence rate was 70%. The mean and median recurrence free survival was 39.6 and 44 months, respectively. Two of the three patients who remained recurrence free at the end of the 60 months had low grade tumours.

CONCLUSION

Early recognition of follicular dendritic cell sarcomas requires a high index of suspicion and bi-modality or tri-modality treatment may cure a subset of low and high grade tumours respectively and prolong recurrence in a large subset of patients. Surgery is the mainstay and the definitive modality of treatment; the advantages and benefit of adjuvant radiotherapy and chemotherapy are yet to be established. Tri-modality management may have a role in high grade patients which needs to be substantiated in future studies.

Braf mutation in interdigitating dendritic cell sarcoma: a case report and review of the literature

Interdigitating dendritic cell sarcoma is an extremely rare tumor. The diagnosis is difficult and is based on clinical, pathological and immunohistochemical evaluation. Differential diagnosis includes melanoma, mesenchymal and hematological malignancies. The mainstay of treatment is surgery for limited disease and different chemotherapy combinations have been tested for advanced disease. No evidence from prospective trials is currently available. We report the case of a 59 year-old male patient who experienced axillary lymphadenopathy with initial diagnosis of large-cell lung cancer on tumor biopsy. He underwent surgical resection with radical intent. Pathological diagnosis of interdigitating dendritic cell sarcoma was obtained on surgical samples. Nine months after radical surgery, he experienced systemic recurrence of disease and underwent chemotherapy with epirubicin and ifosfamide for 4 courses. During chemotherapy, he developed brain disease progression and underwent whole-brain radiotherapy. Systemic progression was then observed and molecular characterization was performed. B-RAF evaluation resulted positive for V600E mutation and the patient was treated with Vemurafenib according to molecular findings. He thus obtained initial clinical benefit but eventually died of brain hemorrhage. In conclusion, we report a case of B-RAF mutation detected in an interdigitating dendritic cell sarcoma patient treated with targeted therapy. B-RAF pathway could have a role in pathogenesis and evolution of this rare disease and could open new perspectives of treatment.

Complete Remission in Systemic Skin Interdigitating Dendritic Cell Sarcoma after ABVD Chemotherapy

Interdigitating dendritic cell sarcoma (IDCS) is a rare and aggressive neoplasm that is thought to arise from dendritic cells. This disease usually involves the lymph nodes and, rarely, extra-nodal sites. We report a 62-year-old man presenting skin nodules in the head, body, and extremities, as well as bone marrow involvement. Morphologic analysis of a biopsied specimen from the skin lesion was consistent with IDCS. Immunohistochemical staining demonstrated that the tumor cells were positive for IDCS-associated antigens such as CD4, CD45, CD68 (KP-1), and S-100 protein. Complete remission was achieved by treatment with 6 cycles of ABVD (adriamycin, bleomycin, vinblastine, and dacarbazine) chemotherapy. Although the optimal treatment of IDSC remains unknown, the experience in the current case supports the notion that ABVD chemotherapy may be effective for IDCS, and further extends this idea to rare patients presenting multiple skin lesions.

Mammary myofibroblastoma in the right lateral abdominal wall

Background

A mammary-type myofibroblastoma is a rare soft tumor; extramammary myofibroblastomas are especially rare.

Case presentation

A 51-year-old woman presented to our department for evaluation of a mass on the right lower abdominal wall. The mass was then excised completely. Gross examination showed a huge, well-circumscribed soft tissue mass. The pathologic diagnosis was an extramammary myofibroblastoma. There was no recurrence after excision at the 6-month follow-up visit.

Conclusions

A mammary-type myofibroblastoma is a benign soft tissue neoplasm. No malignant behavior and/or recurrence of mammary-type myofibroblastomas after surgical resection have been described as a function of size and location. The present case aimed to provide a possible differential diagnosis for such abdominal masses.

Histiocytic differentiation in acute monocytic leukemia

Myeloid histocytes of dendritic cells (DCs), Langerhans cells (LCs), and macrophages in varied tissues, as leukemic blasts in acute monoblastic and monocytic leukemia (AML-M5a and M5b), are derived from monocyte progenitors in bone marrow. Based on DC induction from hematopoietic stem cells, myeloid progenitors, and monocytes, and occasional expressions of histocyte-related antigens (HRAs) in M5, we presume some M5 cases share histiocytic phenotypes originally. To clarify the conception, 93 M5 cases were tested with antibodies for HRAs, CD1a, CD163, S100, fascin, and langerin by immunostaining, and their morphologic characteristics were studied by light and transmission electron microscopy. The study revealed that 23 M5 cases were positive for two or more kinds of HRAs and shared a serial of histocytic immunophenotype and morphologic features, which were closely associated with M5b subtype and expression of CD14 in M5.

Antitumor cytotoxicity induced by bone-marrow-derived antigen-presenting cells is facilitated by the tumor suppressor protein p53 via regulation of IL-12

Activated antigen-presenting cells (APC) deliver the three signals cytotoxic T cells require to differentiate into effector cells that destroy the tumor. These comprise antigen, co-stimulatory signals and cytokines. Once these cells have carried out their function, they apoptose. We hypothesized that the tumor suppressor protein, p53, played an important role in generating the antitumor response facilitated by APC. CD11c⁺ APC derived from p53 wild-type (wt) mouse (wt p53) GM-CSF bone marrow cultures (BMAPC) and activated had reduced survival compared to BMAPC from p53 null consistent with p53-mediated apoptosis following activation. There was a lower percentage of antigenic peptide/MHC I complexes on antigen-pulsed p53 null cells suggesting p53 played a role in antigen processing but there was no difference in antigen-specific T cell proliferative responses to these cells in vivo. In contrast, antigen-specific cytotoxicity in vivo was markedly reduced in response to p53 null BMAPC. When these cells were pulsed with a model tumor antigen and delivered as a prophylactic vaccination, they provided no protection against melanoma cell growth whereas wt BMAPC were very effective. This suggested that p53 might regulate the requisite third signal and, indeed, we found that p53 null BMAPC produced less IL-12 than wt p53 BMAPC and that p53 bound to the promoter region of IL-12. This work suggests that p53 in activated BMAPC is associated with the generation of IL-12 required for the differentiation of cytotoxic immune responses and an effective antitumor response. This is a completely new role for this protein that has implications for BMAPC-mediated immunotherapy.

Follicular dendritic cell sarcoma: two rare cases and a brief review of the literature

Follicular dendritic cell sarcoma (FDCS) is a rare malignant tumor recognized in recent years. It accounts for only 0.4% of soft-tissue sarcomas, and its underlying causes are largely unknown. A correct diagnosis can be difficult to make. Diagnosis of FDCS depends on the combined clinical examination, histopathologic features, electron microscopic examination and confirmation with immunohistochemical studies. Here, we report two rare cases of FDCS: one case involving multiple bones, and the other involving extensive abdominal and pelvic cavities. Clinical, histopathological, and immunohistochemical aspects, therapeutic options, and a related literature review of the two cases are discussed. As the prevalence of FDCS is increasing, the details of these rare cases may highlight the importance and facilitate treatment of similar diseases.

Follicular dendritic cell sarcoma with extensive lymph node involvement: A case report

Follicular dendritic cell sarcoma (FDCS) is an extremely rare neoplasm originating from the follicular dendritic cells in the lymphoid follicles. Current knowledge on its pathogenesis is limited and a well-defined treatment is required. The main channel through which clinicians obtain practical information on FDCS is via studying published case reports. To enrich the existing available literature and enhance the understanding of this rare disease, the present study describes a case of FDCS with extensive lymph node involvement in a 65-year-old male patient whose predominant symptom was a recurrent fever. The diagnosis of FDCS was eventually established based on the immunohistochemical staining of biopsy specimens of the cervical lymph nodes. The patient improved and symptoms disappeared after one cycle of systemic chemotherapy.

Fatal juvenile xanthogranuloma presenting as a sellar lesion: case report and literature review

INTRODUCTION

Juvenile xanthogranuloma (JXG) is a histiocytic condition in the spectrum of non-Langerhans histiocytosis that preferentially affects children. Rarely this condition can involve the central nervous system (CNS) with devastating consequences.

METHODS

The authors report the unique case of an 11-year-old child who initially presented with a sellar lesion without evidence of the cutaneous stigmata typical of JXG. She was later discovered to have JXG following initial diagnosis of granulomatous hypophysitis, with development of widespread intracranial disease and subsequent neurological deterioration. She underwent subtotal resection of her sellar lesion followed by whole brain radiation and systemic chemotherapy; however, she succumbed to her disseminated disease within 1 month of the JXG diagnosis.

CONCLUSIONS

This is a rare case of fatal disseminated intracranial JXG without cutaneous manifestations. Additionally, the initial presentation as a sellar lesion is particularly unusual and seldom described in the literature.

Langerhans cell histiocytosis with multisystem involvement in an infant: A case report

Langerhans cell histiocytosis (LCH) is a proliferative disease of histiocyte-like cells, with a wide range of clinical presentations that vary from a solitary lesion to more severe multifocal or disseminated lesions. The disease can affect any age group; however, the peak incidence rate is in infants aged between 1 and 3 years-old. Diagnosis of LCH should be based on the synthetical analysis of clinical presentations, in addition to features of imaging and histopathology. Although certain cases regress spontaneously, other patients require systemic chemotherapy together with the administration of steroids. The present study reports the case of an infant with LDH with multisystem involvement, including that of the bone, skin, orbit, spleen and lungs. The patient received chemotherapy and obtained rapid improvement in the involved systems. A total of 2.5 years after completion of the therapy, the patient still remains in follow-up and no evidence of active disease has been noted.

Follicular dendritic cell sarcoma with atypical features surrounding undescended testis: description of a rare case

Dendritic cell tumors are extremely rare neoplasms and occur both in nodal and extranodal sites. We report a case of an intra-abdominal follicular dendritic cell sarcoma (FDCS). The aim of this study is to describe histological, immunohistochemical, and ultrastructural features of FDCS in order to better define an abdominal mass with unusual immunophenotype and atypical clinical and radiological presentation.

Follicular dendritic cell sarcoma of the stomach: case report and review of the literature

Follicular dendritic cell sarcoma (fdcs) is a rare entity, often presenting a diagnostic challenge for both the pathologist and the clinician. It accounts for only 0.4% of soft-tissue sarcomas, and its underlying causes are largely unknown. Most of these tumours occur in lymph nodes, and extranodal involvement is uncommon. In the gastrointestinal tract, fdcs is extremely rare. Here, we report a case of primary fdcs originating in the stomach. Upon review of the literature, we identified only 2 additional cases of fdcs presenting as a primary stomach tumour. Given the rarity of this tumour in gastrointestinal sites and the lack of consensus on treatment, evaluation of this entity must continue.

Splenic inflammatory pseudotumor-like follicular dendritic cell tumor

Inflammatory pseudotumor of the spleen with expression of follicular dendritic cell markers is an extremely rare lesion with only a few cases reported previously. The present study reports on an inflammatory pseudotumor of the spleen 10 × 8 × 7 cm in size that was incidentally found in a 61-year-old man and increased gradually in size during a period of 3 months. Abdominal ultrasonography revealed a well-circumscribed splenic mass, and abdominal computed tomography confirmed the presence of a well-circumscribed isodense lesion in the splenic hilum with inhomogenous enhancement in the early-phase images and no enhancement on delayed-phase contrast-enhanced images. Magnetic resonance imaging of the abdomen showed a well-defined isodense tumor on T1-weighted images with mildly increased signal intensity on T2-weighted images, and this is only the second study that provides MRI findings of this entity. The patient underwent an uncomplicated open splenectomy for definitive histologic diagnosis. Under microscopic examination, the lesion was an admixture of lymphocytes, plasma cells and spindle cells. In situ hybridization analysis for Epstein-Barr virus (EBV) revealed that most of the spindle cells were positive for EBV, and immunochemistry showed the expression of the follicular dendritic cell markers CD21, CD35 and CD23 within the tumor. The diagnosis of inflammatory pseudotumor-like follicular dendritic cell tumor was established.

Transformation of Castleman's disease into follicular dendritic cell sarcoma, presenting as an asymptomatic intra-abdominal mass

Follicular dendritic cell (FDC) sarcoma is an extremely rare malignant neoplasm arising from FDCs. The exact origin of FDCs remains unclear; both a hematopoietic lineage origin and a stromal cell derivation have been proposed. Proliferation of FDCs can lead to benign reactive lesions or generate neoplastic conditions. The lesions are most commonly found in lymph nodes and usually involve the head and neck area. Castleman's disease is a rare non-neoplasitic lymphoproliferative disorder. Rare cases of hyaline-vascular Castleman's disease have been associated with FDC sarcoma, but a clonal relationship has not been convincingly demonstrated. A pathway toward tumor evolution, beginning with hyperplasia and dysplasia of FDCs, has been proposed. Despite this known association between Castleman's disease and FDC sarcoma, there have only been few reported cases of sarcoma arising as a complication of pre-existing Castleman's disease, especially in abdominal lesions. We describe here a 51-year-old female with an FDC sarcoma arising from unicentric, hyaline-vascular type Castleman's disease in an intra-abdominal mass. Pathologically, the lesion showed a series of changes during the process of transformation from Castleman's disease to FDC sarcoma. (Korean J Gastroenterol 2013;62:131-134).

A 46-year-old Chinese woman presenting with retroperitoneal follicular dendritic cell sarcoma: a case report

Introduction

Follicular dendritic cells are non-phagocytic, non-lymphoid cells of the immune system that are necessary for antigen presentation and the regulation of reactions in the germinal centers of the lymph nodes. Follicular dendritic cell sarcoma is an unusual cancer, particularly in the intra-abdominal region. In the present report we describe an unusual case of retroperitoneal follicular dendritic cell sarcoma that emphasizes the difficulty of diagnosing and treating this tumor. Retroperitoneal follicular dendritic cell sarcoma has only been rarely reported in the literature to date.

Case presentation

A 46-year-old Chinese woman of Han ethnicity presented with chronic right lower quadrant abdominal pain over the preceding 4 weeks. The tumor was resected and submitted to histopathological examination. The case was verified as retroperitoneal follicular dendritic cell sarcoma by microscopic examination and immunohistochemical analysis. After diagnosis, she received postoperative radiotherapy and chemotherapy. She has survived 3 years postoperatively, although she has a pulmonary metastasis.

Conclusions

Retroperitoneal follicular dendritic cell sarcoma may demonstrate aggressive potential. This study indicated that postoperative adjuvant radiotherapy and chemotherapy could extend the survival of a patient with retroperitoneal follicular dendritic cell sarcoma.

Follicular Dendritic Cell Sarcoma of Ileoceacal Region in a Young Woman: A Rare Case Report with Review of Literature

Follicular dendritic cell sarcoma arises from the follicular dendritic cells present in the lymph nodes, especially of the head and neck area. Rarely, extranodal sites may be affected including tonsil, the oral cavity, liver, spleen and the gastrointestinal tract. Here, we report a case of intra-abdominal follicular dendritic cell sarcoma presenting as a huge mass in the ileocecal region of a 24-year young woman.

Interdigitating dendritic cell sarcoma presenting simultaneously with acute myelomonocytic leukemia: report of a rare case and literature review

Interdigitating dendritic cell sarcoma (IDCS) is an extremely rare tumor derived from interdigitating dendritic cells. We report the first case of a 64-year-old Chinese woman who was diagnosed with simultaneous IDCS and acute myelomonocytic leukemia (AML-M4). The patient had undergone chemotherapy for breast cancer 6 years previously. Based on the laboratory results, both the IDCS and the AML-M4 in this patient were determined to be of myelogenous origination. Furthermore, a review of 62 IDCS cases (Medline database, key word: IDCS) reported to date revealed that as many as 17 % of the patients had malignant disease and received radiotherapy and/or chemotherapy prior to developing IDCS, and that this group of patients showed worse prognosis compared with counterparts. The patient in the present report showed poor response to four cycles of sequential chemotherapy, and died 6 months after the initial diagnosis.

Paraneoplastic pemphigus associated with dendritic cell neoplasm and Castleman’s disease: report of a new case and review of the literature

We report on a patient with longstanding multicentric Castleman’s disease, hyaline-vascular type, who developed a follicular dendritic cell sarcoma, and finally presented a fatal paraneoplastic pemphigus. We review all four cases of such a triple association described in the literature so far.

Follicular dendritic cells: origin, function, and different disease-associated patterns

Follicular dendritic cells (FDCs) are a specialized type of antigen-presenting dendritic cells that are largely restricted to lymphoid follicles. They form dense three-dimensional meshwork patterns within benign follicles, which maintain the follicular architecture. The FDC function is to bind and retain antigens by linking to complement and immune complexes and then present these antigens to germinal center B cells that start the secondary immune response. FDCs aid in the rescue of bound B cells from apoptosis, and induce the differentiation of B cells into long-term memory B cell clones or plasma cells. We will discuss the different patterns of the FDC meshwork observed in different types of reactive and neoplastic disorders, which may be due to underlying different roles that FDCs may play in these disorders and whether changes in the architecture of the FDC meshwork can be useful in routine diagnostic practice or have a prognostic value.

Successful treatment of disseminated interdigitating dendritic cell sarcoma with adriamycin, bleomycin, vinblastine, and dacarbazine chemotherapy

Interdigitating dendritic cell sarcoma (IDCS) is a very rare and aggressive neoplasm that arises from antigen presenting cells. IDCS usually involves lymph nodes; however, extra-nodal involvement has also been reported. Because a consistent standard therapy for IDCS has not been established to date, we report a case of the successful treatment of disseminated IDCS using ABVD chemotherapy (doxorubicin, bleomycin, vinblastine, and dacarbazine). A 64-year-old man was diagnosed with IDCS on the basis of immunohistochemical findings of a biopsy specimen of the inferior nasal concha. Immunohistochemical staining showed a positive reaction for CD68, leukocyte common antigen, and S-100 protein, but a negative reaction for CD34, CD1a, and CD21. Imaging studies showed cervical and axillary lymphadenopathies, subcutaneous nodules, and a soft tissue lesion in the nasal cavity. Treatment with the ABVD regimen resulted in complete remission after 8 cycles of chemotherapy.