Enhanced CT Findings in a Case of Recurrent Pelvic Follicular Dendritic Cell Sarcoma.

INTRODUCTION: Follicular Dendritic Cell Sarcomas (FDCS)was first found in 1986; the specificity of the disease is its rarity, with an incidence of only 0.4%, numerous doctors for its lack of understanding, the accuracy of imaging diagnosis is not great, which is easy to delay the treatment. This article summarizes several characteristic imaging manifestations of FDCS to provide imaging physicians with an understanding of the imaging properties of this rare disease. When faced with complex cases, the radiologist can consider this disease and include it in the differential diagnosis. FDCS occurs mainly in lymph nodes, mainly in the head and neck. The main symptoms are fatigue, local pain, or painless mass. The treatment method is not uniform, but scholars agree that we should strive for the opportunity of surgery as much as possible. CASE PRESENTATION: This paper reported a case of FDCS with pelvic recurrence 3 years after surgery. The patient was suspected to have lymphoma by postoperative pathology in the local hospital, and it is recommended that the patient be reexamined regularly. A soft tissue mass was recently found again in the left pelvic cavity. After an enhanced CT examination, the radiologist was skeptical of the previous diagnosis of lymphoma. Subsequently, a needle biopsy was performed at Peking University Shougang Hospital. The pathological results rejected the prior diagnosis of lymphoma after consultation with additional hospitals, and the patient was diagnosed with FDCS. CONCLUSIONS: The imaging manifestations of FDCS lack absolute specificity, but it also has imaging characteristics, such as large areas of necrosis in the huge mass, rough mass calcification in the mass, enhanced scan showed "fast in and slow out" mode, and there were blood vessels in the tumor. FDCS mainly occurs in lymph nodes and is easily misdiagnosed as GIST, inflammatory myoblastoma, lymphoma, etc. Radiologists should continue to collect cases of this disease and include suspected cases in the differential diagnosis in clinical work.

18 F-FDG PET/CT Versus 68 Ga-FAPI PET/CT in a Case of Isolated Nodal-Type Follicular Dendritic Cell Sarcoma.

ABSTRACT: Follicular dendritic cell sarcoma is a rare low-grade sarcoma originating from mesenchymal dendritic cells. We presented 18 F-FDG and 68 Ga-FAPI PET/CT findings in a 32-year-old woman with pathologically confirmed nodal-type follicular dendritic cell sarcoma. In this case, follicular dendritic cell sarcoma demonstrated lower uptake with FAPI than FDG.

FDG PET/CT in Follicular Dendritic Cell Sarcoma of the Jejunum With Hepatic Metastasis.

ABSTRACT: Follicular dendritic cell sarcoma of the gastrointestinal tract is a rare malignancy. We describe contrast-enhanced CT and FDG PET/CT findings in a case of jejunal follicular dendritic cell sarcoma with hepatic metastasis. The primary jejunal tumor showed inhomogeneous enhancement on contrast-enhanced CT and intense FDG uptake on PET/CT mimicking adenocarcinoma or gastrointestinal stromal tumor. The hepatic metastatic tumor showed hypovascularity on contrast-enhanced CT and mild FDG uptake on PET/CT. This case indicates that follicular dendritic cell sarcoma should be included in the differential diagnosis of the hypermetabolic intestinal lesions.

18 F-FDG PET/CT in Extensive Follicular Dendritic Cell Sarcoma With Response Assessment to Chemotherapy.

ABSTRACT: Follicular dendritic cell sarcoma (FDCS) is a low-grade sarcoma of mesenchymal dendritic cell origin, and it constitutes <0.4% of soft tissue sarcomas. We report a rare case of FDCS in a 32-year-old man. 18 F-FDG PET/CT demonstrated the involvement of cervical, axillary, mediastinal, abdominal, and pelvic groups of lymph nodes and spleen. A cervical lymph node biopsy suggested FDCS. 18 F-FDG PET/CT scan done after 3 cycles of chemotherapy (CHOP regime) revealed a complete metabolic response. This case presents the rarity of extensive presentation and complete response to the CHOP regime.

Pancreatic follicular dendritic cell sarcoma: one case report and literature review.

Pancreatic follicular dendritic cell sarcoma (FDCS) is a rare neoplasm with unclear pathological characteristics. In this study, we report one case of pancreatic FDCS and review published cases to summarize the characteristics and treatment of pancreatic FDCS. A man in his early 30 s was admitted for jaundice, abdominal fullness, and weight loss for 15 days. Computed tomography revealed a large capsule solid mass in the pancreatic head together with a dilated bile duct and enlarged retroperitoneal lymph nodes. Serum biochemistry revealed high total bilirubin levels (313.9 µmol/L) and normal tumor marker levels. Pancreatoduodenectomy was performed, but no chemotherapy was administrated at the patient's behest. The pathologic diagnosis was pancreatic FDCS infiltrating the duodenal seromuscular layer and common bile duct. The patient presented with liver metastasis 3 months after surgery and died 8 months after surgery from multiorgan failure. Pancreatic FDCS is a rare disease with high invasiveness. Our previous case exhibited paraneoplastic syndrome together with this disease, and further investigation is needed to confirm whether paraneoplastic syndrome is a typical syndrome of pancreatic FDCS.

Radiologic and Histopathologic Features of a Neck-Localised Follicular Dendritic Cell Sarcoma: A Case Report and Literature Review.

Follicular dendritic cell sarcoma (FDCS) is an uncommon tumour. The pathological features of FDCS have been extensively described in the literature, but there are few reports on its imaging features. A 48-year-old man presented at our hospital with a mass in the left submandibular region without associated oral complaints. Contrast-enhanced magnetic resonance imaging revealed a mass with smooth margins, and postoperative histopathological and immunohistochemical findings were consistent with FDCS. At present, our understanding of FDCS is still insufficient, and its diagnosis is dependent on pathological evaluation. We aim to provide a bit of information for clinicians to consider when they see these types of tumours. Key Words: Follicular dendritic cell sarcoma, Magnetic resonance imaging, Imaging features, Histopathology.

Concomitant malignancies in the neck: follicular dendritic cell sarcoma; a rare tumour presenting as a right-sided neck nodal mass and papillary carcinoma thyroid.

Follicular dendritic cell sarcoma is a rare low-grade sarcoma of mesenchymal origin. It involves the lymph nodes more commonly and rarely extranodal sites. The most common lymph node is cervical and usually presents as a painless asymptomatic mass. More often, it is a misdiagnosis, and there is a delay in treatment. It is rarely associated with Castleman disease, myasthenia gravis. Diagnosis of this condition is by histopathology and immunochemistry. Surgery is the primary modality of treatment, and adjuvant therapy has been tried with no definite trials due to the rarity of the disease. Here, we report a case of concomitant follicular dendritic sarcoma of the right cervical lymph node and papillary carcinoma of the thyroid managed in our institute. There was a line of investigations approaching towards a diagnosis, and she underwent total thyroidectomy and right modified radical neck dissection.

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.

Intra-muscular follicular dendritic cell sarcoma in the thigh: A case report.

RATIONALE: Follicular dendritic cell sarcoma (FDCS) is an intermediate-grade malignancy originating from follicular dendritic cells. Nodal FDCS is the most common type, meaning that the extranodal type may not be recognized and could be easily misdiagnosed. Reported extranodal sites include the head and neck, retroperitoneum, spleen, liver, and gastrointestinal tract. FDCS in the soft tissue is extremely rare. PATIENT CONCERNS: A 75-year-old male presented with complaints of a localized swelling and intra-muscular soft tissue mass in the left upper thigh. DIAGNOSIS: The present tumor consisted of fascicular or vague storiform-arranged spindle cells with less pleomorphism and many lymphoid aggregates. Tumor cells were positive for CD21, CD35, CD68, vimentin, and EGFR. Intra-muscular FDCS was confirmed by immunohistochemical studies. INTERVENTIONS: The patient received a wide marginal excision, followed by adjuvant radiotherapy. OUTCOMES: Symptomatic improvements were achieved and no subsequent relapses were observed. LESSONS: If the tumor arises in the extranodal sites, especially in the soft tissue, it is difficult to include FDCS in the differential diagnosis. When the immunoprofile is not consistent with that of common spindle cell tumors, immunostaining for follicular dendritic cell markers such as CD21, CD23, and CD35, as well as further immunohistochemistry for D2-40, CD68, EGFR, Epstein-Barr virus, and BRAF can be helpful for the diagnosis and subtyping of FDCS. To the best of our knowledge, the present case is the first case of intramuscular FDCS.

Postoperative liver metastasis of primary inflammatory pseudotumorous follicular dendritic cell sarcoma of the spleen: a case report.

Follicular dendritic cell sarcoma (FDCS) is a rare and low incidence tumor. So far, there is no standard treatment for the disease. Surgery is the main treatment for FDCS. Here, we report the case of a 51-year-old woman who was admitted with the chief complaint of "spleen-occupying lesion detected via physical examination more than 1 month ago". Spiral plain scan and enhanced computed tomography (CT) of the upper abdomen showed a vascular-derived tumor, with a high possibility of hemangioma or hemangiolymphangioma. Later, on 25 December 2019, the patient underwent laparoscopic splenectomy, and the pathological diagnosis of primary splenic FDCS was made. The patient did not receive adjuvant chemotherapy or radiotherapy. At a regular follow-up inspection 11 months later, on 18 December 2020, an abdominal scan + enhanced CT revealed multiple new abnormal intrahepatic nodules, which combined with her history, indicated the possibility of metastases. Subsequently, she was readmitted to hospital and surgical treatment was decided upon after multi-disciplinary consultation and discussion. Laparoscopic S1/S3/S4/S5 hepatectomy plus cholecystectomy was performed on 31 December 2020. The postoperative pathology findings revealed (liver tumor, S3, S4, S5) metastatic inflammatory pseudotumor follicular dendritic sarcoma, tumor diameter 0.6-1.2 cm. Due to the lack of clinical reports on postoperative organ metastasis of this disease, less experience, and controversy in drug selection of radiotherapy and chemotherapy, the patient refused to receive radiotherapy and chemotherapy. She now undertakes regular outpatient reexamination, and has been followed-up until now, during which time she has not progressed, and the efficacy is considered satisfactory.

Hepatic inflammatory pseudotumor-like follicular dendritic cell tumor: a case report.

BACKGROUND: Inflammatory pseudotumor-like follicular dendritic cell sarcoma is a rare histological variant of follicular dendritic cell sarcoma involving typically the spleen and the liver, often linked to the presence of Epstein-Barr virus infection. Definite diagnosis of this type of sarcoma is difficult to make owing to nonspecific clinical and imaging findings and is based on histopathological features. Inflammatory pseudotumor-like follicular dendritic cell sarcoma is described as a low-aggressivity tumor with a favorable prognosis. CASE PRESENTATION: We report the case of a 34-year-old Caucasian woman, Epstein-Barr virus positive, diagnosed with hepatic inflammatory pseudotumor-like follicular dendritic cell sarcoma and surgically treated in November 2014, who developed 6 years later a recurrence for which she underwent once again surgical treatment. As far as we know, fewer than 30 reports of inflammatory pseudotumor-like follicular dendritic cell liver tumors have been reported in the English literature. CONCLUSIONS: Although it is an uncommon tumor, inflammatory pseudotumor-like sarcoma is a diagnostic worth being taken in consideration, and surveillance is recommended owing to the possibility of recurrence.

18F-FDG PET/CT in Uterine Follicular Dendritic Cell Sarcoma.

ABSTRACT: A 46-year-old woman presented with menorrhagia, abdominal distension, and neck mass for 3 months. Ultrasonography detected a large intra-abdominal mass and enlarged neck lymph nodes. Further 18F-FDG PET/CT scan revealed lesions with intense 18F-FDG avidity in abdominal cavity and neck. The patient underwent a biopsy of the uterine, and the diagnosis of uterine follicular dendritic cell sarcoma was finally achieved. After 6 cycles of CHOP-like chemotherapy, 18F-FDG PET/CT showed complete metabolic and morphologic resolution for follicular dendritic cell sarcoma.

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.

Follicular Dendritic Cell Sarcomas: CT and MRI Findings in 20 Patients.

OBJECTIVE. The objective of this study was to assess the imaging features of follicular dendritic cell sarcoma (FDCS) on CT and MRI. MATERIALS AND METHODS. The clinical data and pretreatment findings of 20 patients with pathologically proven FDCS on CT (n = 15), MRI (n = 7), or both (n = 2) were analyzed retrospectively. Tumor location, number, size, morphology, attenuation or signal intensity, margin, presence of metastases, and contrast enhancement were evaluated. RESULTS. FDCS originated from lymph nodes (n = 6) or a variety of extranodal sites (n = 14). The tumors were typically solitary and well-circumscribed. Extranodal lesions (mostly in the abdomen or mediastinum with mean diameter, 11.8 cm) were larger than nodal lesions (mean diameter, 6.5 cm). Nodal-type cases presented with homogeneous masses on CT and MRI. However, on CT, all extranodal tumors (n = 12) showed heterogeneous attenuation, of which 91.7% (11/12) contained areas of lower attenuation because of internal necrosis and 50.0% (6/12) showed calcifications. On MRI, primary hepatic or splenic tumors (n = 3) also appeared as large heterogeneous masses. Seven patients (35.0%) had advanced-stage disease, and intraabdominal extranodal cases were more likely to have regional lymphadenopathy (n = 4) and distant metastases (n = 5). Hypervascularity was seen in 90.0% (18/20) of patients and progressive enhancement was seen in 11 (78.6%) of 14 tumors with multiphase imaging. CONCLUSION. FDCS is a rare, mostly solitary, well-delineated malignancy. A nodal-type FDCS typically presents as a small homogeneous mass, whereas an extranodal FDCS in the mediastinum or abdomen manifests as a large heterogeneous mass with internal necrosis and calcifications accompanied by regional lymphadenopathy. Hypervascularity and progressive enhancement can be seen in the majority of tumors.