Follicular dendritic cell tumor of the liver associated with Epstein-Barr virus

Mesenchymal Neoplasms of the Liver

Mesenchymal neoplasms of the liver can be diagnostically challenging, particularly on core needle biopsies. Here, I discuss recent updates in neoplasms that are specific to the liver (mesenchymal hamartoma, undifferentiated embryonal sarcoma, calcifying nested stromal-epithelial tumor), vascular tumors of the liver (anastomosing hemangioma, hepatic small vessel neoplasm, epithelioid hemangioendothelioma, angiosarcoma), and other tumor types that can occur primarily in the liver (PEComa/angiomyolipoma, inflammatory pseudotumor-like follicular dendritic cell sarcoma, EBV-associated smooth muscle tumor, inflammatory myofibroblastic tumor, malignant rhabdoid tumor). Lastly, I discuss metastatic sarcomas to the liver, as well as pitfalls presented by metastatic melanoma and sarcomatoid carcinoma.

Case report: Hepatic inflammatory pseudotumor-like follicular dendritic cell sarcoma: a rare case and review of the literature

Inflammatory pseudotumor-like follicular dendritic cell sarcoma (IPT-like FDCS) is a rare subtype of follicular dendritic cell sarcoma (FDCS) that primarily occurs in the liver and spleen. The etiology of IPT-like FDCS is unknown, and it has nonspecific clinical manifestations, imaging performance and laboratory test results. Recently, a patient with IPT-like FDCS was admitted to our hospital because of abdominal distension and anemia. Over the past 3 years, the patient has been followed up after a liver mass was found in a physical examination. The lesion gradually enlarged and caused compression symptoms. In November 2022, a tumor with a diameter of approximately 20 cm was found in the right posterior lobe of the liver after abdominal enhanced Magnetic resonance imaging (MRI) in our hospital. Liver tumor biopsy before the operation revealed a large number of hyperplastic plasma cells and a small number of spindle cells, and the spindle cells were atypical. After a complete examination, the patient underwent liver resection. Pathology after surgery confirmed liver IPT-like FDCS.

Challenges in the Diagnosis of Epstein-Barr Virus-positive Inflammatory Follicular Dendritic Cell Sarcoma: Extremely Wide Morphologic Spectrum and Immunophenotype

Epstein-Barr virus (EBV)-positive inflammatory follicular dendritic cell (FDC) sarcoma (EBV + IFDCS) is a rare entity, and its histopathological characteristics have not been fully described. Here, we investigated the wide morphologic spectrum and immunophenotype of this tumor with the aim to help avoid misdiagnosis. Thirteen cases of EBV + IFDCS were retrospectively analyzed, combined with a review of 70 cases reported in the literature. The median age of patients was 49 (range, 29 to 67 y). Six patients were male and 7 were female. Most cases (92.3%, 12/13) occurred in the liver or spleen, and only 1 case affected an extra-hepatosplenic site (lung, 7.7%, 1/13). Tumors were assessed for a variety of histologic features and assigned to the following morphologic groups: classic type (53.8%, 7/13), lymphoma-like subtype (38.5%, 5/13), and hemangioma-like subtype (7.7%, 1/13). The classic type had distinct EBV-positive neoplastic cells with a fascicular or storiform growth pattern, variable lymphoplasmacytic infiltrates, and blood vessels. The lymphoma-like subtype had extremely prominent lymphoplasmacytic infiltrates (resembling marginal zone lymphoma with plasmacytoid differentiation) with singly dispersed distinct EBV-positive neoplastic cells, highlighted by in situ hybridization for EBV-encoded small RNA. The hemangioma-like subtype had extremely prominent blood vessels with hyaline and/or fibrinoid degeneration, singly dispersed distinct EBV-positive neoplastic cells, and limited lymphoplasmacytic infiltrates. Immunohistochemically, the neoplastic cells showed variable staining for FDC markers (CD21, CD35, CD23, and SSTR2) and the fibroblastic marker SMA, with the staining ranging from very focal to extensive. The number of EBV-positive neoplastic cells ranged from 80 to 400/HPF. All cases showed variable expression of PD-ligand 1 (PD-L1) (CPS: 5-90). IgG4-positive cells ranged from rare up to 100/HPF. Interestingly, 2 cases satisfied the criteria proposed in a previous study, mimicking IgG4-related disease. EBV + IFDCS is an entity with an extremely wide morphologic spectrum and immunophenotype. Awareness of the spectrum of morphologic presentations of this rare tumor, specifically the lymphoma-like subtype and hemangioma-like subtype, is important for accurate diagnosis.

Epstein-Barr virus-associated inflammatory pseudotumor variant of follicular dendritic cell sarcoma of the liver: a case report and review of the literature

BACKGROUND

Follicular dendritic cell sarcoma is a rare stromal tumor with no standard treatment. However, some reports have revealed that follicular dendritic cell sarcoma has an inflammatory pseudotumor variant associated with Epstein-Barr virus infection that has a relatively good prognosis. In this report, we present a case of a resected inflammatory pseudotumor variant of follicular dendritic cell sarcoma of the liver, and have reviewed the literature on the clinicopathological, molecular, and genomic features of this tumor.

CASE PRESENTATION

The inflammatory pseudotumor variant of follicular dendritic cell sarcoma originates only in the liver or spleen, causes no symptoms, and is more common in middle-aged Asian women. It has no characteristic imaging features, which partially explains why the inflammatory pseudotumor variant of follicular dendritic cell sarcoma is difficult to diagnose. Pathologically, the inflammatory pseudotumor variant of follicular dendritic cell sarcoma has spindle cells mixed with inflammatory cells and is variably positive for follicular dendritic cell markers (CD21, CD23, and CD35) and Epstein-Barr virus-encoded RNA. On genetic analysis, patients with this tumor high levels of latent membrane protein 1 gene expression and extremely low levels of host C-X-C Chemokine Receptor type 7 gene expression, indicating that the inflammatory pseudotumor variant of follicular dendritic cell sarcoma has a latent Epstein-Barr virus type 2 infection.

CONCLUSIONS

The inflammatory pseudotumor variant of follicular dendritic cell sarcoma is an Epstein-Barr virus-associated tumor and a favorable prognosis by surgical resection, similar to Epstein-Barr virus-associated gastric cancer.

Promising clinical outcome after body gamma knife radiotherapy for mediastinal follicular dendritic cell sarcoma with thoracic spine invasion and iliac metastasis: A case report and literature review

Background

Follicular dendritic cell sarcoma (FDCS) is a rare type of intermediate grade tumor. Mediastinal FDCS with spinal invasion has not been well described. The treatment options include surgical resection and radiation therapy. The body gamma knife is a stereotactic body radiotherapy (SBRT) technology that is widely used in China. The pathological evaluation of a bone lesion after a body gamma knife procedure has not been reported. Here, we report a case of a patient with FDCS with thoracic spine invasion and iliac metastasis treated with surgery and body gamma knife.

Case summary

A 36-year-old male patient was hospitalized at Zhongshan Hospital, Fudan University, due to a gradually aggravated pain on the lateral side of the left scapula for 6 months. Imaging examination showed neoplastic lesions on the left side of C7-T2 invading the vertebral body of T1, T2, and caput costae of the second rib and suspected metastasis in the left ilium. FDCS was diagnosed after performing a computed tomography (CT)-guided core needle biopsy, and the thoracic lesion was surgically resected. The body gamma knife was used as an adjuvant radiotherapy for the thoracic lesion and a primary therapy for the left ilium lesion. Iliac bone lesion resection was performed at Zhongshan Hospital, Fudan University, 10 weeks after RT. Compared with the biopsy report, the body gamma knife treatment resulted in a pathological complete response (PCR). The magnetic resonance imaging (MRI) examinations showed stable disease of the thoracic lesion after body gamma knife radiosurgery.

Conclusion

This case report describes the treatment of mediastinal FDCS with thoracic spinal invasion and iliac metastasis. The promising outcome suggests that separation surgery is an effective treatment option for mediastinal FDCS with spinal column invasion. It also demonstrates the application prospects of the body gamma knife treatment in malignant lesions of the axial bones.

Hepatic Follicular Dendritic Cell Sarcoma with Epithelioid Morphology: Histopathologist's Perspective

Follicular dendritic cell (FDC) sarcoma is an uncommon tumor of the liver with only 30 previous cases reported in the English literature. Histopathological examination is the gold standard for the diagnosis of FDC sarcoma although the diagnosis is often missed because of its rarity. It usually presents with spindle-cell morphology although epithelioid/biphasic morphology is also well-known. This morphological variation can also pose a diagnostic challenge. We discuss a case of unresectable hepatic FDC sarcoma in an adult male who was diagnosed in core biopsy. We highlight the relevant histomorphological differentials and diagnostic approaches to FDC sarcoma in this anecdote.

Hepatic inflammatory pseudotumor-like follicular dendritic cell tumor with hepatic lymphoma history: A case report and literature review

RATIONALE

Hepatic inflammatory pseudotumor (IPT)-like follicular dendritic cell (FDC) sarcoma is a very rare disease. Till now, only 19 cases were reported in the English literature. However, the coexistence of IPT-like sarcoma and non-Hodgkin lymphoma (NHL) in the same patient has never been reported. In this report, we presented a case of hepatic IPT-like FDC with hepatic NHL history of which both were successfully resected.

PATIENT CONCERNS

We reported a case of a 47-year-old male patient who presented with right upper abdominal discomfort. Nineteen years ago, he underwent liver resection of segment VII for hepatic NHL (B-cell lymphoma). He had a history of chronic hepatitis B virus infection. Serum alpha fetoprotein level was normal. However, imaging studies revealed a well-circumscribed, solid mass in the right hepatic lobe, he came back to the clinic because he was worried about a recurrence of the B-cell lymphoma.

DIAGNOSES

Based on the patient's past medical history and magnetic resonance imaging results, and he was diagnosed as hepatocellular carcinoma or hepatic NHL preoperatively.

INTERVENTIONS

Right hemi-hepatectomy was performed on this patient.

OUTCOMES

Histological report showed features of a mixture of chronic inflammatory cells and variable amounts of spindle cells. Also, immuno-histo-chemical studies demonstrated that all the tumor cells showed strong nuclear in situ labeling for EBV-encoded small RNAs and strongly positive stainings with CD21 and CD35. The patient tolerated the surgery well, recovered smoothly and he was discharged on postoperative day 7 (day 7). The patient is still disease free after a follow-up of over 50 months.

CONCLUSIONS

To our knowledge, this is the first report demonstrating hepatic IPT-like FDC sarcoma in a patient with primary hepatic NHL history. In regards to treatment, complete surgical resection should be performed and would acquire excellent long-term outcomes.

Imaging features and radiologic-pathologic correlations of inflammatory pseudotumor-like follicular dendritic cell sarcoma

Background

Inflammatory pseudotumor-like follicular dendritic cell sarcoma (IPT-like FDCS) is a rare tumor. This study aimed to reveal the radiological characteristics of IPT-like FDCS by radiologic-pathologic correlation.

Results

We analyzed two cases of IPT-like FDCS in the liver, nine in the spleen, and two in both the liver and spleen concomitantly. IPT-like FDCS presented as well-defined iso- or hypodense masses on unenhanced computed tomography (CT) images in both the liver and spleen. Hyperintensities on T1-weighted images and hypointensities on T2-weighted images with hypointense rings were characteristic features in splenic cases. “Halo signs” were observed in two out of three liver tumors. Hepatic lesions showed significant enhancement, whereas splenic lesions showed only mild enhancement. Delayed annular enhancement was observed in both liver and spleen cases. On ultrasonographic examination, IPT-like FDCS presented as hypoechoic lesions with enhancement similar to that observed on CT. Hyaline fibrous pseudocapsules, which correlated with the hypointensities on T2-weighted images, were microscopically observed at the tumor edge. IPT-like FDCS was characterized by an abundance of small blood vessels and capillaries. Capillaries were also found in the fibrous capsule of some IPT-like FDCSs, which may explain the delayed annular enhancement.

Conclusions

The manifestations of IPT-like FDCS in the liver and spleen showed differences that warrant them to be approached differently during diagnosis. Characteristic radiological findings of IPT-like FDCS included different enhancement patterns between liver and spleen tumors and rim-like hypointensities on T2-weighted images, as well as annular enhancement on CT and magnetic resonance images. These imaging features correlated with tumor pathology.

Epstein-Barr virus-negative inflammatory pseudotumor-like variant of follicular dendritic cell sarcoma of the liver: A case report and literature review

Follicular dendritic cell sarcoma (FDCS) can be divided into the conventional type, and the inflammatory pseudotumor (IPT)-like variant type. Epstein-Barr virus (EBV) infection is considered to be closely associated with the pathogenesis of IPT-like variant of FDCS. Hepatic FDCS has an exceedingly low incidence of only 29 cases reported, with most of these tumors being classified as the IPT-like type. We report a case of an IPT-like variant of FDCS of the liver in a 61-year old man who presented with no marked symptoms. The patient underwent laparoscopic surgery for the mass and was well during a 13-month follow-up periods. The postoperative pathological examination found a proliferation of spindle cells and a diffuse infiltration of inflammatory cells within the tumor. Immunohistochemistry revealed that neoplastic cells were positive for CD23, clusterin, fascin, and PD-L1, and weakly positive for CD35, SMA, and D2-40. The infiltrating lymphocytes were strongly positive for PD1, and IgG4-positive plasma cells were less than 10 cells/high-power field. In situ hybridization for Epstein-Barr virus encoded RNA (EBER) was negative. To our knowledge, the present case is the second case of hepatic IPT-like variant of FDCS without EBV involvement, indicating that EBV infection is not an absolute prerequisite for a diagnosis of the IPT-like variant of FDCS.

Follicular dendritic cell sarcoma detected in hepatogastric ligament: A case report and review of the literature

The most common organ where follicular dendritic cell sarcoma (FDCS) occurs is in cervical lymph nodes, while few cases are found in extranodal organs such as liver, spleen, and soft tissue. This is a case report that FDCS occurs in the hepatogastric ligament. To our knowledge, there is no such case that has been reported previously. A 47-year-old male patient was found to have an intraabdominal mass during an annual physical examination. Computed tomography showed a 4.2 cm × 4.1 cm mass located at the lesser curvature of the stomach, above the pancreas. During operation, a tumor mass was found in the hepatogastric ligament and a radical resection was performed. The tumor was diagnosed as FDCS by pathology and immunohistochemical testing. The patient had a favorable recovery, and no obvious abnormality was found 3 months post-operation.

Follicular dendritic cell sarcoma of the liver with metachronous small bowel and splenic metastases: a case report and literature review

Follicular dendritic cell sarcoma (FDCS) of the liver is an extremely rare disease, accounting for a mere 0.4% of all soft tissue sarcomas. FDCS most commonly involves lymph nodes but also affects extranodal sites such as the gastrointestinal system, oral cavity, liver, spleen and pancreas, albeit less commonly. It is widely considered a low-to-intermediate grade malignancy. We report a case of FDCS with metachronous involvement of the liver, small intestines and spleen, its imaging, histological findings and its management.

Hepatic inflammatory pseudotumour-like follicular dendritic cell tumor: A case report

Hepatic inflammatory pseudotumor (IPT)-like follicular dendritic cell (FDC) tumor is a rare neoplasm. We herein report the case of 19-year-old female patient with an IPT-like FDC tumor and summarize 24 cases of hepatic FDC tumors previously reported in the English literature. The patient presented with complaints of abdominal discomfort, without significant laboratory abnormalities, and underwent surgical removal of a hepatic tumor. The resected tumor was 6 cm in the longest diameter and the tumor cells were positive for CD21, CD35 and Epstein-Barr virus (EBV). The postoperative course was uneventful and there have been no metastases or recurrence during 1 year of follow-up. The majority of the cases of hepatic IPT-like FDC tumors have a female predominance and exhibit an association with EBV infection. Their clinical manifestations and image findings are usually non-specific and the diagnosis of this disease mainly relies on pathology.

Extranodal Follicular Dendritic Cell Sarcoma Originating in the Pancreas: A Case Report

Follicular dendritic cell (FDC) sarcoma is a type of malignant tumor that originates from immune system-related FDCs. Pancreatic FDC sarcoma is a rare disease, and the specificity of the clinical presentation and laboratory results is unknown. We report the clinical process and imaging features of one case of pancreatic FDC sarcoma. A 67-year-old woman presented with a hypoechoic mass between the spleen and left kidney during a medical examination. The patient was hospitalized for further diagnosis. Her laboratory results did not present any obvious abnormal changes. Unenhanced and contrast-enhanced pancreatic computed tomography scans indicated a round mass with heterogeneous attenuation in the pancreatic tail, and a 3.5 × 3.6-cm solid mass with a cystic component was noted. Clear-cut, slight contrast enhancement was present in the solid part, whereas contrast enhancement was not observed in the cystic part. In addition, no obvious dilation was observed in the pancreatic duct, and no swollen lymph nodes were noted in the posterior peritoneum. Routine and contrast-enhanced pancreatic magnetic resonance imaging scans showed an abnormal signal indicative of a mass in the pancreatic tail, with a diameter of ∼35 mm and a clear boundary. A T2-weighted imaging scan showed a slight hyperintensity coupled with part of a hyperintensity, whereas T1-weighted imaging showed a slight hypointensity coupled with part of a hypointensity, and diffusion-weighted imaging showed a heterogeneous hyperintensity. The solid part of the lesion showed poor contrast enhancement through contrast-enhanced scanning, but contrast enhancement was not observed in the cystic part. Surgical tumor resection was performed, and the pathological diagnosis was pancreatic FDC sarcoma. The tumor did not recur based on short-term CT reexamination. Pancreatic FDC sarcoma is a rare disease, and the established clinical examinations and laboratory tests lack specificity. Imaging reveals a solid mass with a cystic component and a clear boundary. In addition, the solid part exhibits poor contrast enhancement. Although pancreatic occurrence is rare, a clinical pancreatic solid tumor with a cystic component should be identified by differential diagnosis.

Inflammatory Pseudotumor-like Follicular Dendritic Cell Tumor of the Spleen: Case Report and Review of the Literature

A 74-year-old woman underwent contrast-enhanced (CE) computed tomography (CT) that revealed an enlarging splenic lesion. This splenic tumor was suspected as metastasis because the patient had been diagnosed with right breast cancer with lung and right axillary lymph node metastases 4 years earlier and had undergone surgery and hormone therapy at another hospital. T2-weighted imaging of magnetic resonance (MR) imaging demonstrated the tumor with slightly high intensity with a rim of low intensity at the margin. On dynamic contrast-enhanced (DCE)-MR imaging after intravenous administration of gadolinium diethylenetriamine pentaacetic acid, delayed enhancement was observed in the center and margin of the tumor. On positron emission tomography with 2-deoxy-2-[18F] fluoro-D-glucose (FDG) integrated with CT, the tumor showed high FDG uptake. Splenic metastasis was considered based on the imaging findings, lack of inflammation on laboratory data, and clinical course, so she underwent splenectomy. Histopathologically, the tumor was encapsulated by a fibrous structure, which was depicted as the rim at the tumor margin on T2-weighted imaging and DCE-MR imaging. Immunohistochemical study allowed the diagnosis of inflammatory pseudotumor (IPT)-like follicular dendritic cell tumor (FDCT). FDCT is a primary neoplasm of lymph nodes that shows features of follicular dendritic cell differentiation, and it is rare at the spleen. Differential diagnosis is difficult between IPT-like FDCT and similar splenic tumors, such as IPT, splenic metastases, hamartoma and hemangioma. However, in addition to the enhancement pattern within a tumor on DCE-MR imaging, detection of the capsular-like rim on MR imaging might aid the diagnosis of splenic IPT-like FDCT.

Follicular Dendritic Cell Sarcoma of the Inflammatory Pseudotumor-like Variant Presenting as a Colonic Polyp

Follicular dendritic cell (FDC) sarcoma is rare and is classified either as conventional type or inflammatory pseudotumor (IPT)-like variant. Extranodal presentation is uncommon and nearly all gastrointestinal FDC tumors are of the conventional type. IPT-like variant tumors occur almost exclusively in the liver and spleen and are consistently associated with Epstein-Barr virus (EBV). Here we report the case of a 78-year-old woman with an IPT-like FDC sarcoma presenting as a pedunculated colonic polyp. Histologically, scanty atypical ovoid to spindle cells were mixed with a background of florid lymphoplasmacytic infiltrate, which led to an initial misdiagnosis of pseudolymphoma. These atypical cells expressed CD21, CD23, CD35, and D2-40, and were positive for EBV by in situ hybridization, confirming the diagnosis. The patient was free of disease five months after polypectomy without adjuvant therapy. Although extremely rare, the differential diagnosis for colonic polyp should include FDC sarcoma to avoid an erroneous diagnosis. A review of the 24 cases of IPT-like FDC sarcoma reported in the literature reveal that this tumor occurs predominantly in females with a predilection for liver and spleen, and has a strong association with EBV.

Follicular dendritic cell sarcoma of parapharyngeal space: a case report and review of the literature

Follicular dendritic cell sarcoma (FDCS) of the parapharyngeal space is a rare malignant tumor. Only eleven cases of FDCS of the parapharyngeal space have been reported in English literature. Most of the reported cases developed tumor recurrence within 1 year or had metastasis. Because of the rarity of FDCS in the parapharyngeal space and peculiar histology, it can be misdiagnosed as undifferentiated carcinoma or meningioma. Therefore, pathologists should be aware of the existence of FDCS in this location. This paper aims to report a unique case of FDCS of the parapharyngeal space without recurrence in 26 months follow up with a review of the literature.

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.

Follicular dendritic cell sarcoma of the pharyngeal region

Follicular dendritic cell sarcoma (FDCS) is a rare neoplasm arising most commonly from follicular dendritic cells in the lymph nodes. It is exceedingly rare in extranodal sites, particularly in the pharyngeal region. The present study reports 3 cases occurring in the pharyngeal region. Case 1 had tonsil and cervical lymph node involvement, while case 3 also had tonsil involvement. Cases 1 and 3 relapsed locally at 3 and 17 months after surgery, respectively. Case 2 was diagnosed with a tumor in the parapharyngeal space and the patient succumbed to the disease 5 months after treatment with combined surgery and chemotherapy. All 3 cases were misdiagnosed initially. Pathological biopsy examination, including histopathology and immunohistochemistry, was essential for diagnosis. The data for 52 cases, including cases from the literature and the present cases, were analyzed. The results indicated that 57% (26/46) of the initial diagnoses were inaccurate, while the recurrence, metastasis and mortality rates were 40, 16 and 10%, respectively. The statistics supported the theory that FDCS of the pharyngeal region is a low-grade sarcoma. Involvement of the tonsils (52%, 27/52) and parapharyngeal space (19%, 10/52) were observed most commonly, while FDCS at various sites showed different prognoses. The various survival rates were calculated in the present study. The large tumors (≥4 cm) had a poorer prognosis than the small tumors (<4 cm; P<0.05). Among the 50 cases with available follow-up data, 46% (23/50) were treated with surgery alone, 52% (26/50) with combination therapy (surgery followed by chemotherapy and/or radiotherapy) and 2% (1/50) with surveillance. There was no statistically significant evidence (P>0.05) that combination therapy improves survival rates, compared with surgery alone.

Interdigitating dendritic cell sarcoma of the liver and lung: a case report with morphohological and immunohistochemical features of tumor

Interdigitating dendritic cell sarcoma is extremely rare neoplasm that mainly occurs in the lymph nodes. Only 45 cases have been reported in the literature to date. We report a case of this sarcoma arising from the liver and lung, a previosly unreported site for this neoplasm. An 19-year-old girl deteriorated rapidly after artificial abortion and died 4 weeks later. Autopsy showed markedly enlarged liver and lung with numerous nodules up to 0.5 centimeters in diameter. Microscopically, nodules was composed of large pleomorphic cells that were immunohistochemically positive for proteins S-100 and vimentin, some of them expressed positivity to fascin and CD 68, with a rich small CD3 positive T lymphocytic infiltrateite around them. Based of these findings, the present case was diagnosed as interdigitating dendritic cell sarcoma, a neoplasm that remains a diagnostic and clinical challenge, because it can mimic a wide variety of other malignant tumors and tumor-like lesions.

Inflammatory angiomyolipoma of the liver: a rare hepatic tumor

Angiomyolipoma (AML) is a rare mesenchymal neoplasm of the tumor, composed of a varying heterogeneous mixture of three tissue components: blood vessels, smooth muscle and adipose cells. Hepatic AML may demonstrate a marked histological diversity. We herein present one case of hepatic AML exhibiting prominent inflammatory cells in the background, which happened in a 61-year-old Chinese female patient, without signs of tuberous sclerosis. Histologically, the striking feature was the infiltration of numerous inflammatory cells in the background, including small lymphocytes, plasma cells, and eosnophils. The tumor cells were spindled and histiocytoid in shape, with slightly eosinophilic cytoplasm, and arranged along the vessels or scattered among the inflammatory background. Sinusoid structure was obviously seen in the tumor. Mature adipocytes and thick-walled blood vessels were focally observed at the boundaries between the tumor and surrounding liver tissues. The tumor cells were positive immunostaining for HMB-45, Melan-A, and smooth muscle actin. The inflammatory AML should be distinguished from other tumors with inflammatory background such as inflammatory myofibroblastic tumor and follicular dendritic cell tumor and deserves wider recognition for its occurrence as a primary hepatic tumor.

Follicular dendritic cell sarcoma of the liver: unusual presentation of a rare tumor and literature review

BACKGROUND

Hepatic follicular dendritic cell (FDC) sarcoma is an extremely rare neoplasm. Most commonly, FDC sarcoma presents as a solitary mass in lymph nodes, however, several extra-nodal locations have been identified.

METHODS

We report a case of a 53-year-old female who presented with symptoms of abdominal pain, fever, anemia, and jaundice. After an extensive review of the literature, we have found only 12 cases of hepatic FDC sarcoma.

RESULTS

The tumor was 11.5 cm in diameter and composed of spindle and epithelioid cells with ovoid nuclei and associated with mixed inflammatory infiltrate. Immunohistochemical stains were positive for CD35 and CD21. The patient underwent a left hepatic lobectomy.

CONCLUSIONS

Liver follicular dendritic cell sarcoma is a very rare tumor. Most cases present with abdominal pain and weight loss, and most of them can be managed by hepatic resection with excellent short-term outcomes.

Imaging findings of follicular dendritic cell sarcoma: report of four cases

Follicular dendritic cell sarcoma is a rare malignant neoplasm and little is known about its radiological features. We present here four cases of follicular dendritic cell sarcomas and we provide the image characteristics of these tumors to help radiologists recognize this entity when making a diagnosis.

Clinicopathologic features of hepatic follicular dendritic cell sarcoma

AIM: To investigate the clinicopathologic features, diagnosis, treatment and prognosis of hepatic follicular dendritic cell sarcoma.

METHODS: The clinical, pathological and immunohistochemical data for three patients with hepatic follicular dendritic cell sarcoma who were treated at our hospital were collected to analyze the clinicopathologic features, diagnosis, treatment and prognosis of the disease. A literature review was also performed to reveal the characteristics of the disease.

RESULTS: All the tumors showed an infiltrative growth pattern. Two tumors were located in the left lobe of the liver, and one in the right lobe. Histopathology revealed co-existence of the components of spindle cell sarcoma and inflammatory cells. Coagulation necrosis was noted in some areas. Immunohistochemically, tumor cells were strongly positive for CD21, CD23, CD35, vimentin, weakly positive for CD45 and EMA, but negative for CK (Pan), CD34, CD117, Dog-1, actin, SMA, caldesmon, desmin, CD10, CD15, CD30, CD1a, ALK, CD68, CD163, HMB45 and S-100. Inflammatory cells were positive for CD20, CD79a, CD2, CD3, CD45RO and CD38. In all three cases, tumor cells were positive for EBER and EBV. A diagnosis of hepatic follicular dendritic cell sarcoma was made.

CONCLUSION: Hepatic follicular dendritic cell sarcoma is a rare tumor with a high degree of malignancy and should be differentiated from interdigitating dendritic cell sarcoma, sarcomatoid hepatocellular carcinoma, inflammatory myofibroblastoma, extra-gastrointestinal stromal tumor, and histiocytosarcoma.

Follicular dendritic cell sarcoma: a report of six cases and a review of the Chinese literature

Goals

The main purpose of this study is to broaden the clinicopathological spectrum and increase recognition of follicular dendritic cell sarcoma (FDCS) through analysis of the clinical and pathological features of 50 cases.

Methods

The clinicopathological features of total 50 cases of FDCS were analyzed including a review of 44 cases reported in Chinese literature before October 2009 and six original cases from the pathology files conducted by the authors.

Results

The youngest patient came under observation in this study is only seven years old. Including the cases contributed by the authors, our literary review indicated that male dominated the tumor cases (M: F = 3: 2). 28 cases (56%) present with this disease in extranodal sites. Tumor cells demonstrated positive staining for the follicular dendritic cell markers CD21 (47/49), CD35 (43/45), CD23 (20/23) and CD68 (23/25). In situ hybridization for Epstein-Barr virus-encoded RNA was performed in 10 cases. Nevertheless, EBV expression was absent in all these cases. The follow-up analysis of all cases shows that 26 (81.2%) patients were alive and disease free; 6 (18.8%) patients were alive with recurrent disease or metastasis; and nobody had died of this disease at the time of last follow-up.

Conclusions

The diagnosis of the FDCS is based on the findings of morphology and immunohistochemistry. The FDCS occurred in China should be viewed and treated as a low-grade sarcoma, and the role of the EBV in the pathogenesis of this tumor is still uncertain. There is a possibility that the tumor might be racial or geographic correlated, because most cases were reported from Eastern Asia area; it's particular the case of the liver or spleen tumor.

Inflammatory angiomyolipomas of the liver: a clinicopathologic and immunohistochemical analysis of 5 cases

Hepatic angiomyolipoma (AML) may demonstrate a marked histologic diversity. We report 5 cases of hepatic AML exhibiting prominent inflammatory cells in the background (inflammatory AML). The patients were 4 females and 1 male, with age ranged from 21 to 48 years (mean, 39.2 years). Three tumors were in the left lobe and 2 in the right lobe. The tumor size was from 5.5 to 10 cm in the greatest dimension (mean, 7.46 cm). No patient had clinical features of tuberous sclerosis. Histologically, the striking feature was the infiltration of numerous inflammatory cells in the background of the tumors, including small lymphocytes, plasma cells, and histiocytes. The percentage of tumor area with heavy inflammatory infiltration was more than 50% in all cases. The myoid cells were spindled and epithelioid in shape, with eosinophilic or clear cytoplasm, and were arranged in fascicles and clusters. Scattered adipose cells and sinusoidal and thick-walled blood vessels were variably present in all tumors. Focal trabecular arrangement was present in 2 of the 5 tumors. There was no nuclear atypia, and mitotic figures were rare. The myoid cells were diffusely positive for vimentin, smooth muscle actin, and HMB-45 in all cases. All patients showed no evidence of disease after the initial surgical excision during a follow-up period from 3 to 9 years. The inflammatory AMLs should be distinguished from other tumors with inflammatory background such as inflammatory myofibroblastic tumor and follicular dendritic cell tumor.

Clinicopathological features and prognosis assessment of extranodal follicular dendritic cell sarcoma

AIM: To establish a model for prognosis assessment of extranodal follicular dendritic cell (FDC) sarcoma.

METHODS: Nine lesions were examined by routine and molecular approaches. Clinicopathological factors from the new cases and 97 reported cases were analyzed for their prognostic values.

RESULTS: The current lesions were found in five male and four female patients, located mainly in the head and neck area and averaging 7.2 cm in size. Six patients had recurrence or metastasis and three remained free of disease. The 106 patients (male/female ratio, 1.1:1) were aged from 9 to 82 years (median, 44 years). The tumor sizes ranged from 1.5 to 21 cm (mean, 7.4 cm). Abdominal/pelvic region was affected most frequently (43%). Surgical resection was performed in 100 patients, followed by radiation and/or chemotherapy in 35 of them. Follow-up data were available in 91 cases, covering a period of 3-324 mo (mean, 27 mo; median, 19 mo). Of the informative cases, 38 (42%) had recurrence or metastasis, and 12 (13%) died of the disease. These tumors were classified histologically into low- and high-grade lesions. A size ≥ 5 cm (P = 0.003), high-grade histology (P = 0.046) and a mitotic count ≥ 5/10 HPF (P = 0.013) were associated with tumor recurrence. The lesions were defined as low-, intermediate- and high-risk tumors, and their recurrence rates were 16%, 46% and 73%, and their mortality rates 0%, 4% and 45%, respectively.

CONCLUSION: Extranodal FDC tumors behave like soft tissue sarcomas. Their clinical outcomes are variable and can be evaluated according to their sizes and grades.

Follicular Dendritic Cell Tumor in Liver: A Case Report and Collective Review

Follicular dendritic cells (FDC) are a subset of the immune system and present in the germinal centers of lymphoid follicles in the spleen and lymph nodes. They are functionally as antigen-presenting cells and thus improving the quality of the humoral immune response. Follicular dendritic cell tumor is rare but considered low-grade sarcoma. Including our case, there were totally 17 cases with FDC tumor involved the liver from Medline. In these cases, the mean age was 47 years old, ranged from 19 to 82. It was much more common in females than in males (13:4). The clinical manifestations of these patients included abdominal discomfort, palpable mass, weight loss and malaise. The average size of the tumor was 11 cm. Most of the FDC tumors were associated with Epstein-Barr virus expression, 13/17 (76.5%). Surgical resection remains the mainstay of the treatment.

Follicular dendritic cell sarcoma of the abdomen: the imaging findings

Follicular dendritic cell sarcoma is a rare neoplasm that originates from follicular dendritic cells in lymphoid follicles. This disease usually involves the lymph nodes, and especially the head and neck area. Rarely, extranodal sites may be affected, including tonsil, the oral cavity, liver, spleen and the gastrointestinal tract. We report here on the imaging findings of follicular dendritic cell sarcoma of the abdomen that involved the retroperitoneal lymph nodes and colon. It shows as a well-defined, enhancing homogenous mass with internal necrosis and regional lymphadenopathy.