Clinicopathological and Imaging Characteristics of EBV Positive Inflammatory Follicular Dendritic Cell Sarcoma

doi:10.21203/rs.3.rs-4891123/v1

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Clinicopathological and Imaging Characteristics of EBV Positive Inflammatory Follicular Dendritic Cell Sarcoma

https://doi.org/10.21203/rs.3.rs-4891123/v1

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Objective

EBV-positive inflammatory follicular dendritic cell sarcoma (EBV + inflammatory FDCS) is a rare tumor that has been less systematically studied. This study aims to improve the understanding of EBV + inflammatory FDCS by analyzing radiological imaging data and clinicopathological features.

Methods

A retrospective analysis was performed on twelve patients with EBV + inflammatory FDCS confirmed pathologically. Ten patients underwent computed tomography (CT) scans, six underwent magnetic resonance imaging (MRI) scans, and four patients underwent CT and MRI scans simultaneously.

Results

Twelve patients (six in the liver and six in the spleen) had clinically asymptomatic or asymptomatic, and six cases were found on physical examination. Pathologically, the tumor cells dispersed in a background of inflammatory cells. All cases showed positive expression of at least one follicular dendritic cell (FDC) marker and EBV. On unenhanced CT images, nine cases of EBV + inflammatory FDCS presented as well-defined iso-or hypodense masses, and one liver case had an irregularly shaped lesion with unclear borders. All cases showed iso-or hypodensity signals on T1WI and mixed signals on T2WI. The hepatic lesions showed marked enhancement in arterial phase and diminished enhancement in portal vein phase and delayed phase, whereas the splenic lesions showed mild enhancement in arterial phase and continued enhancement in portal vein phase and delayed phase .

Conclusion

EBV + inflammatory FDCS is a rarely low-grade malignant tumor, which exists the possibility of local lymph node metastasis and recurrence. Therefore, the preoperative diagnosis is expected to improve by carefully analyzing the imaging features and clinical characteristics of the patients.

EBV positive inflammatory follicular dendritic cell sarcoma

computed tomography

magnetic resonance imaging

ultrasonography

Infammatory pseudotumor-like follicular dendritic cell sarcomais a rare, Epstein-Barr virus (EBV)–associated neoplasm, characterized by spindly tumor cells dispersed in a background of small lymphocytes and plasma cells. In 2022, the World Health Organization has named infammatory pseudotumor-like follicular dendritic cell sarcomais as EBV positive inflammatory follicular dendritic cell sarcoma (EBV + inflammatory FDCS). EBV + inflammatory FDCS is inert in biological behavior, and surgical resection can achieve good long-term efficacy^[1]. Therefore, accurate diagnosis before surgery is very important. To our knowledge, EBV + inflammatory FDCS has mainly been reported in case studies analyzing clinicopathological features with only a little previous literatures incorporating imaging findings. The purpose of this study is to improve the diagnosis of EBV + inflammatory FDCS and provide a basis for clinical diagnosis by analyzing the radiological and clinicopathological features of twelve cases with EBV + inflammatory FDCS from Hunan Provincial People’s Hospital /The First Affiliated Hospital of Hunan Normal University.

Subjects

Twelve patients with EBV + inflammatory FDCS confirmed by surgical pathology were enrolled from January 2018 and June 2023. As shown in Table 1, the patients included three males and nine females, with an average age of 53-year-old (rang, 31–71years). Six patients (50.0%) presented with abdominal distention or abdominal pain or fever, and six patients (50.0%) were incidentally found during health checkups. Serum tumor marker examinations including α-fetoprotein (AFP), carcinoembryonic antigen (CEA), carbohydrate antigen 199 (CA199), and carbohydrate antigen 125 (CA125) revealed that twelve patients had no significant abnormalities. Hepatitis B virus surface antigen was negative in twelve patients. Preoperative images and postoperative pathological data of all patients were reviewed. Follow-up data were obtained by telephone. Informed consent was obtained from patients upon research authorization by the Medical Ethics Committee of Hunan Provincial People Hospital (IRB Approval No.[2024]-72).

Table 1

Clinical characteristics of EBV + inflammatory FDCS patients (n = 12)
Case no	Sex	Age (years)	Location	Symptoms	Examination method	Initial Diagnosis	Treatment	outcome
1	F	56	Spleen	No	CT and MRI	SANT	Surgical excision	Tumor-free survival
2	F	35	Liver (S6)	No	MRI, ultrasound	HCC	Surgical excision	Tumor-free survival
3	F	71	Spleen	Pain in the right upper abdomen	CT, ultrasound	Spleen space -occupying lesions	Surgical excision	Tumor-free survival
4	F	31	Liver (right lobe)	Intermittent fever	MRI, ultrasound	HCC	Surgical excision	Tumor-free survival
5	M	48	Liver (right lobe)	No	CT, ultrasound	HCC	Surgical excision	Recurrence, survival with tumor
6	F	65	Spleen	No	CT	Dysplasia	Surgical excision	Tumor-free survival
7	F	61	Spleen	No	CT and MRI ultrasound	Spleen space -occupying lesions	Surgical excision	Tumor-free survival
8	M	66	Spleen	Pain in the left upper abdomen	CT and MRI ultrasound	SANT	Surgical excision	Tumor-free survival
9	M	32	Liver (S6)	Pain in the right upper abdomen	CT, ultrasound	HCC	Surgical excision	Tumor-free survival
10	F	57	Liver (S8)	Pain in the right upper abdomen	CT, ultrasound	Liver space -occupying lesions	Surgical excision	Tumor-free survival
11	F	59	Spleen	No	CT	SANT	Surgical excision	Tumor-free survival
12	F	60	Liver (S7)	Pain in the abdomen	CT and MRI ultrasound	ICC	Surgical excision	Tumor-free survival
Note—F = female, M = male, HCC = hepatocellular carcinoma, ICC = intrahepatic cholangiocarcinoma, SANT = sclerosing angiomatoid nodular transformation of the soleen.

Image Acquisition

Patients underwent the abdominal CT or MRI examinations. CT was performed in ten patients, MRI in six patients, both CT and MRI in four patients.

The CT examinations were performed using the following two systems: Philips Brilliance iCT (Netherlands) (n = 4) or Neusoft NeuViz 64i CT (Shenyang, China) (n = 6). The acquisition parameters were as follows: tube voltage of 120 kVp, tube current of165–375 mA determined by automatic tube current adjustment, slice thickness of 5 mm, and pitch of 0.984:1. Contrast-enhanced CT was performed after a bolus intravenous injection of 1.5 mL/kg of a nonionic contrast agent (350mgI/mL, 100mL, Shanghai General Electric Pharmaceutical Co., Ltd, Shanghai, China) through the anterior cubital vein by dual cylinder high-pressure injector (Ulrich, Germany) at a rate of 3.0–4.0mL/s. After injection of contrast agent, the arterial phase (AP)and portal vein phase (PP) and delayed phase (DP)scanning were performed at a delay of 25–30s, 60–65s and 120s, respectively.

MRI was performed using a Siemens Magnetom Trio A Tim System 3.0t MR scanner (Germany) with a torso coil. The routine MRI protocol was performed and consists of the following MRI sequences: a T2-weighted imaging (T2WI) fast spin-echo or turbo spin-echo sequence, a fat-suppressed respiratory-triggered heavily T2WI sequence, and a T1-weighted imaging (T1WI) gradient-recalled echo sequence with and without chemically selective fat suppression. diffusion-weighted imaging(DWI)was performed using a respiratory-triggered single-shot echo-planar sequence with b values of 0 and 800 s/mm2. Contrast-enhanced MRI was performed with dimeglumine gadopentetate (12mL, Guangzhou Kangchen Pharmaceutical Co., Ltd, Guangzhou, China) was intravenously injected through the anterior cubital vein by dual cylinder high-pressure injector, the dose of contrast agent was about 20–24mL(0.4mL/kg), and the flow rate was 2.0 ~ 3.0mL/s. Contrast enhanced images were obtained with a scanning delay of 20 ~ 25s (AP) and 60–65s (PP) and 120s (DP) after the start of contrast agent injection.

Nine of the twelve patients underwent ultrasound imaging using the Philips S2000 or Toshiba Aplio500 (Toshiba, Tokyo, Japan) system, and one of them underwent contrast-enhanced ultrasound. The frequency of the convex array probe is 3.5-5.0 MHz.

Image Analysis

Two associate professors read the images independently, and the resulting quantitative data were averaged. If the qualitative data were inconsistent, the two radiologists read the images again and reached a verbal consensus. Main parameters include lesion site (accurate to segment), number (single or multiple), size (maximum diameter(cm), accurate to one decimal point), shape (round, oval, irregular or lobulated), margin (clear or unclear, capsule or not), density/signal (homogeneous or heterogeneous, calcification, hemorrhage, cystic/necrosis), enhanced images (enhanced mode, degree), adjacent tissues and metastasis (invasion of adjacent viscera, vascular embolus, lymph node, metastasis).

Ultrasonography analysis: Two associate professors read the images independently and the resulting quantitative data were averaged. If the qualitative data did not agree, the two sonographers would read the images again and reach a verbal consensus. The main parameters included: lesion site, number, size, shape, margins, internal echoes, color doppler flow, enhancement.

Pathologic Evaluation

In all twelve cases, the tumors were resected, and the tissue samples were examined using hematoxylin and eosin (HE) staining as well as immunohistochemical EnVision staining. The antibodies that were used are listed in Table 2. Two pathologists with 18 years of experience analyzed the histopathologic specimens after surgery. Appropriate positive and negative controls were evaluated simultaneously. In situ hybridization for Epstein–Barr virus (EBV)-encoded RNA (EBER) was performed in the twelve cases using an EBV probe in situ hybridization kit (Novocastra, Newcastle upon Tyne, United Kingdom). The manufacturer’s instructions were followed with no modification, and a known positive control was used to ascertain the sensitivity of the assay.

Table 2

Antibodies used for immunostaining
Antibodies	Source	Clonality	Dilution	pretreatment
CD21	Maixin	Monoclonal	ready-to-use	HT
CD35	Maixin	Monoclonal	ready-to-use	HT
CD23	Maixin	Monoclonal	ready-to-use	HT
CD30	Maixin	Monoclonal	ready-to-use	HT
CD34	Maixin	Monoclonal	ready-to-use	HT
S-100	Maixin	Monoclonal	ready-to-use	HT
Desmin	Maixin	Monoclonal	ready-to-use	HT
ALK	Maixin	Monoclonal	ready-to-use	HT
SMA	Maixin	Monoclonal	ready-to-use	HT
CD68	Maixin	Monoclonal	ready-to-use	HT
CD1a	Maixin	Monoclonal	ready-to-use	HT
CD20	Maixin	Monoclonal	ready-to-use	HT
CD3	Maixin	Monoclonal	ready-to-use	HT
CK-P	Maixin	Monoclonal	ready-to-use	HT
HT High-temperature repair 20min in Titan Instrument DNS Repair solution

Surgical Method

All patients underwent surgical excision. Two liver case hepatic segments (S6) resection; hepatic segments (S7) performed in one liver case; hepatic segments (S8) performed in one liver case; hepatic right lobectomy resection in two liver case, and the lymph node dissection was performed in one case. All six spleen cases underwent splenectomy. No tumor tissue was found at the cutting edge of any of the pathologic specimens.

Ultrasonography Findings

As shown in Table 3 and Figs. 1–2. Six patients with hepatic lesions and four patients with splenic lesions underwent ultrasonography examination. One patient had two hepatic lesions and the remaining nine patients had single lesions. Ten lesions were regular or lobulated with well-defined borders (maximal diameters range: 1.4 to 10.6 cm), and only one hepatic lesion was irregular shape with ill-defined border (maximum diameter:10.9 cm). Eight lesions showed uneven internal echoes with peripheral hypoechoic or hyperechoic halo in three hepatic lesions and even internal echoes in three lesions. Color Doppler flow imaging showed punctate or striated flow signals within eight lesions, in which peripheral circumferential flow signals were seen in three hepatic lesions and two splenic lesions. Only one patient with hepatic lesion underwent contrast-enhanced ultrasonography, which showed rapid hyperenhancement in AP and hypoenhancement in PP and DP.

Table 3

Preoperative US Findings of Eleven Patients with EBV + inflammatory FDCS
Case No.	Site	Number	Maximum Diameter (cm)	Shape	Margins	internal echo	CDFI	Enhancement Pattern
1	Liver (S6)	1	1.8	regular	clear	even internal echoes	NA	Rapid high enhancement AP, low enhancement in PP and DP
2	Liver (right lobe)	2	3.8 and 2.1	regular	clear	low uneven internal echoes and peripheral ring hyperechoic bands	flow signals around the tumor	None
3	Liver (right lobe)	1	10.9	irregular	unclear	uneven internal echoes	rich flow signals within the tumor	None
4	Liver (S6)	1	5.6	regular	clear	slightly high even internal echoes, and peripheral hypoechoic halo	punctate flow signals within and around the tumor	None
5	Liver (S8)	1	1.4	regular	clear	even internal echoes	NA	None
6	Liver (S7)	1	5.4	regular	clear	low uneven internal echoes, and peripheral hypoechoic halo	punctate flow signals within tumor	None
6	Spleen	1	6.1	regular	clear	low uneven internal echoes	punctate flow signals within the tumor	None
7	Spleen	1	7.2	regular	clear	low uneven internal echoes	NA	None
8	Spleen	1	10.6	lobulated	clear	low uneven internal echoes	punctate or striated flow signals within and around the tumor	None
9	Spleen	1	4.4	regular	clear	low uneven internal echoes	flow signals within and around the tumor	None
Note— NA = not available. CDFI = color doppler flow.

CT Findings

As shown in Table 4 and Figs. 1–2, the imaging characteristics of EBV + inflammatory FDCS differed slightly between the liver and spleen. Four liver cases and six spleen cases underwent CT examination. Nine cases showed heterogeneous hypodensities with rounded or lobulated borders on unenhanced CT, with multiple punctate foci of calcification within one splenic lesion. Only one hepatic lesion had an irregular shape with ill-defined accompanied by multiple lymph node metastases in the portahepatric area, and the diameter of largest lymph node was approximately 3.5 cm. On enhancement scanning, all four hepatic lesions showed significant enhancement in AP, decreased enhancement in PP and DP. In these four hepatic lesions, one hepatic lesion showed "fast in -fast washout" with nonenhancement necrosis area in the lesion; and one hepatic lesion showed striated foci of relative hypoenhancement in the center of the lesion in AP, and the extent of relative hypoenhancement in the center was smaller than before in PP and DP. All six splenic lesions showed mild to moderate enhancement in AP and continued enhancement in PP and DP. Among the 6 splenic lesions, four lesions showed patches of necrosis without enhancement, and one lesion showed irregular peripheral enhancement. Two liver cases were misdiagnosed as HCC, one liver case was misdiagnosed as ICC; three spleen cases were misdiagnosed as sclerosing angiomatous nodular transformations (SANT), and one spleen case was misdiagnosed as a misshapen tumor or hemangioma.

Table 4

Preoperative CT Findings of Eleven Patients with EBV + inflammatory FDCS
Case No.	site	Number	Maximum Diameter (cm)	Shape	No-contrast	Arterial phase	Portal phase and delayed phase	Dynamic enhancement pattern
1	Liver (right lobe)	1	10.9	I	Huge ill-defined heterogeneous hypodensity	marked heterogeneous enhancement with necrosis without enhancement	Enhancement attenuation	fast in -fast washout
2	Liver (S6)	1	5.6	O	Well-defined heterogeneous hypodensity	marked enhancement with relatively low enhancement focus in the center	Enhancement attenuation and relative smaller low enhancement extent in the center than before	fast in -fast washout
3	Liver (S8)	1	1.4	O	Well-defined heterogeneous hypodensity	marked enhancement	Enhancement attenuation	fast in -fast washout
^a4	Liver (S7)	1	5.4	O	Well-defined heterogeneous hypodensity	heterogeneous enhancement	Enhancement attenuation
^a5	Spleen	1	8.1	O	Well-defined heterogeneous hypodensity	Heterogeneous mild enhancement	marked heterogeneous enhancement with patchy necrosis without enhancement	Heterogeneous sustained enhancement
6	Spleen	1	6.1	O	Well-defined heterogeneous hypodensity	Patchy marked enhancement	Progressive enhancement with some non-enhancement hypointense foci	Heterogeneous sustained enhancement
7	Spleen	1	5.1	O	Well-defined heterogeneous hypodensity	Uneven hypoenhancement	Progressive enhancement with patchy non-enhancement foci	Heterogeneous sustained enhancement
^a8	Spleen	1	7.2	O	Well-defined heterogeneous hypodensity	Irregular peripheral enhancement	Irregular peripheral enhancement	Heterogeneous sustained enhancement
^a9	Spleen	1	10.6	L	Well-defined heterogeneous hypodensity with multiple punctate calcifications	Mild enhancement	Progressive mild enhancement	Heterogeneous sustained enhancement
10	Spleen	1	4.4	O	Well-defined heterogeneous iso-low density	Mild enhancement	Progressive mild enhancement with some non-enhancement hypointense foci	Heterogeneous sustained enhancement
Note—O = oval, L = lobulated, I = irregular. a = Cases 4, 5, 8 and 9 had both CT and MRI scans.

MRI Findings

As shown in Table 5 and Figs. 1–2, three liver cases underwent MRI examination, which revealed four well-defined quasi-circular lesions, one case had two lesions (maximum diameters: 2.1 cm and 3.8 cm, respectively) and the other two cases had one lesion each (maximum diameter: 1.8 cm and 3.8 cm, respectively). All four liver lesions showed mild low signals on T1WI and mild high signals on T2WI, and exhibited high signal on DWI. The two liver cases were markedly enhanced in AP, with clearing changes observed in the venous phase and low uptake changes observed in the hepatobiliary-specific phase (HSP). The other two liver lesions showed mild enhancement with low uptake changes in the HSP. The three spleen cases underwent MRI examination, and all had single lesions (maximum diameters: 7.2 cm, 10.5 cm, and 10.6 cm, respectively) with well-defined. All three splenic lesions showed iso-or low signals on T1WI and mixed signals on T2WI. The splenic lesions showed heterogeneous mild enhancement in AP and progressive enhancement in PP and DP with irregular non-enhancing areas within one lesion and irregular peripheral enhancement in one case.

Table 5

Preoperative MRI Findings of Eleven Patients with EBV + inflammatory FDCS
Case No.	site	Number	Maximum Diameter (cm)	Shape	No-contrast	Arterial phase	Portal phase and delayed phase	Hepatobiliary phas	Dynamic enhancement pattern
1	Liver (S6)	1	1.8	O	Well-defined, slightly longer T1 signal and slightly longer T2 signal, DWI high signal, corresponding ADC value reduced.	marked heterogeneous enhancement	Clearance changes occurred in venous phase	Low uptake rate	fast in -fast washout
2	Liver (S6)	2	3.8 and 2.1	O	Well-defined, long T1 and slightly longer T2,	No obvious enhancement	Mild enhancement	Low uptake rate	Heterogeneous sustained enhancement
^a3	Liver (S7)	1	5.4	O	Well-defined, long T1 signal and long T2 signal, DWI high signal, corresponding ADC value reduced.	heterogeneous enhancement	Enhancement attenuation,Clearance changes	Low uptake rate
^a4	Spleen	1	8.1	O	Well-defined, slightly longer T1 and slightly longer T2, (mixed central signals)	heterogeneous mild enhancement	Progressive enhancement	No	Heterogeneous sustained enhancement
^a5	Spleen	1	7.2	O	Well-defined	Irregular peripheral enhancement	Progressive irregular peripheral enhancement	No	Heterogeneous sustained enhancement
^a6	Spleen	1	10.6	L	Well-defined T1WI slightly longer signal and T2 mixed signal	heterogeneous mild enhancement	Progressive enhancement	No	Heterogeneous sustained enhancement
Note—O = oval, L = lobulated. a = Cases3, 4, 5 and 6 had both CT and MRI scans.

Pathology results

As shown in Fig. 1–2, the pathologic features of EBV + inflammatory FDCS in the liver and spleen were very similar. Macroscopically, the masses were round or oval, solid, grayish-white or grayish-red on section, with well-defined borders, and visible fibrous pseudocapsules extruding into the surrounding tissues. necrosis was present in four cases of larger lesions, and hemorrhage was present in one case. Histological examination showed that the tumor cells were dispersed or arranged in bundles among prominent lymphocytes and plasma cells, with granulomatous changes in two of the splenic cases. Tumor cells were spindle-shaped with indistinct borders and abundant reddish cytoplasm. The nuclei were elongated and vesicular, and the nucleoli were small and obvious. Nuclear division was rare, and multinucleated giant cells were seen in some cases. Immunophenotypically, CD21, CD23 and CD35 were expressed in varying degrees in all twelve cases. By in situ hybridization analysis, all cases were positive for EBER.

EBV + inflammatory FDCS was first reported in 2001 by CHEUK et al^[2]. Its histopathology is different from classical FDCS and is closely related to EBV infection. Compared with classical FDCS, EBV + inflammatory FDCS is more frequently observed in adult female patients, and our study is similar to previous findings[1].The majority of patients were clinically asymptomatic or asymptomatic, in our study population, there were no significant typical symptoms other than those of abdominal discomfort and fever, in addition, the levels of serum tumour markers AFP, CEA, CA199 and CA125 observed in our study were within the normal range, which is consistent with previously reported results^[3]. EBV + inflammatory FDCS is an inert sarcoma, and surgical resection is the first choice of treatment. For patients with tumor recurrence or those who cannot be treated by surgery, chemotherapy or radiotherapy can be administere^[4–7]. Among the twelve patients, only one liver patient with hilar lymph node metastasis recurred more than two years after the first surgical resection, underwent a second surgery and four courses of chemotherapy, and now coexists with the tumor. This suggests that although EBV + inflammatory FDCS is low-grade malignant, local lymph node metastasis and recurrence are still possible.

The diagnosis of EBV + inflammatory FDCS is based on variable numbers of tumor cells in a background of severe inflammation, coupled with supportive immunohistochemistry and is associated with the Epstein–Barr virus, and the best available immunohistochemical markers for EBV + inflammatory FDCS are CD21, CD23 and CD35^{[2; 8]}. All patients in our cohort were positive for at least one FDC marker (CD21, CD35, CD23) and the Epstein–Barr encoding region, so the diagnosis of EBV + inflammatory FDCS was clear.

To date, the imaging findings of EBV + inflammatory FDCS are rarely reported, with most imaging reports coming from individual cases or small cohorts^[9–11]. In our study, we found that EBV + inflammatory FDCS had nonspecific findings on unenhanced ultrasonography, making it difficult to distinguish from other tumours^{[12; 13]}. Only one liver patient underwent CEUS in this study, which showed rapid hyper-enhancement in the arterial phase and hypo-enhancement in the portal and delayed phases, which was consistent with MRI finding. On CT and MRI, intrahepatic and splenic tumours are usually homogeneously or heterogeneously hypointense. In our study, the findings of CT and MRI of EBV + inflammatory FDCS in the liver and spleen are both similar and different. Eight out of ten patients showed heterogeneous density on CT, which may be related to hemorrhagic necrosis of the tumor. The varying degree of tumor necrosis in these cases may be related to the larger size of the tumor as larger masses are more prone to necrosis, seven out of eleven of our cases (diameter > 5 cm) had areas of necrosis with central hypodensity. EBV + inflammatory FDCS revealed weaker enhancement in the spleen than in the liver, which may be related to splenic parenchymal enhancement. All lesions showed inhomogeneous enhancement in the arterial phase, decreased enhancement in the PP of liver lesions, and progressive inhomogeneous enhancement in the PP and DP of splenic lesions. On MRI, like MRI enhancement imaging reported in the literature^{[13; 14]}showing progressive enhancement of tumor parenchyma, in our study, two liver cases showed significant enhancement in AP and diminished enhancement in PP; the other liver case (2 lesions) showed no significant enhancement in AP and mild enhancement in PP and DP, suggesting that MRI enhancement pattern of hepatic FDCs was nonspecific, which may be related to the fact that there were fewer cases in our study. All three splenic lesions showed isointensity or hypointensity on T1WI and heterogeneous on T2WI. Enhancement showed inhomogeneous mild enhancement on AP and progressive enhancement on PP and DP, with irregular non-enhanced areas within one lesion and irregular peripheral enhancement in one case. This may be related to the large size of the mass with hemorrhagic necrosis. Therefore, the imaging manifestations of hepatic and splenic IPT-like FDCS have their own characteristics and need to be differentiated in diagnosis.

The differential diagnosis of EBV + inflammatory FDCS of liver should include inflammatory pseudotumor, HCC, ICC, metastatic tumor, leiomyosarcoma, malignant fibrous histiocytoma, and in spleen should include sclerosing hemangiomatoid nodular transformation (SANT), hamartoma, hemangioma/angiosarcoma, malignant lymphoma. The imaging features of these tumors overlap with those of EBV + inflammatory FDCS, Thus the differential diagnosis is very difficult. Given the rarity of EBV + inflammatory FDCS. Preoperative imaging diagnosis of these tumors can be challenging. The correct final diagnosis depends on histopathological examination and immunohistochemical markers.

EBV + inflammatory FDCS is very rare, usually located in the spleen and liver, and has a lack of clinical specificity. We believe that complete CT and MRI examination may be of great help in the diagnosis of EBV + inflammatory FDCS. When single or multiple masses show different types of enhancement on CT and MRI, EBV + inflammatory FDCS should be considered in the differential diagnosis. However, the final diagnosis should be based on pathological morphology and immunohistochemical examination.

Acknowledgements

Not applicable.

Authors’ contributions

The research was conceived by JZ, XT and HY. XL, YZ and YL conducted a search and analysis of the data. XZ was the one who authored the first draft of the paper and KW drew the figures and tables. The manuscript was revised by JZ, XT and HY. The final document has been reviewed and approved by all of authors.

Funding This study did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Availability of data and materials

The data that supports the fndings of this study are available on request from

the corresponding author upon reasonable request.

Ethics approval and consent to participate

The study was conducted in full compliance with ethical standards, with prior informed consent forms being duly obtained from all patients and their respective family members. Moreover, this research endeavor was approved by the Medical Ethics Committee of Hunan Provincial People Hospital (IRB Approval No.[2024]-72 )

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests

Ge R, Liu C, Yin X, Chen J, Zhou X, Huang C, Yu W, Shen X. Clinicopathologic characteristics of inflammatory pseudotumor-like follicular dendritic cell sarcoma. Int J Clin Exp Pathol 7(5):2421–9.
Cheuk W, Chan JK, Shek TW, Chang JH, Tsou MH, Yuen NW, Ng WF, Chan AC, Prat J. Inflammatory pseudotumor-like follicular dendritic cell tumor: a distinctive low-grade malignant intra-abdominal neoplasm with consistent Epstein-Barr virus association. Am J Surg Pathol. 2001;25(6):721–31. 10.1097/00000478-200106000-00003.
Nguyen BD, Roarke MC, Yang M. Synchronous hepatic and splenic inflammatory pseudotumour-like follicular dendritic cell sarcomas. Liver Int. 2015;35(7):1917. 10.1111/liv.12738.
Choe JY, Go H, Jeon YK, Yun JY, Kim YA, Kim HJ, Huh J, Lee H, Shin DH, Kim JE. Inflammatory pseudotumor-like follicular dendritic cell sarcoma of the spleen: a report of six cases with increased IgG4-positive plasma cells. Pathol Int. 2013;63(5):245–51. 10.1111/pin.12057.
Zhang BX, Chen ZH, Liu Y, Zeng YJ, Li YC. Inflammatory pseudotumor-like follicular dendritic cell sarcoma: A brief report of two cases. World J Gastrointest Oncol. 2019;11(12):1231–9. 10.4251/wjgo.v11.i12.1231.
Aparicio Serrano A, Castro J, Rodríguez E, Gallego, Jiménez, Barrera Baena P. Inflammatory pseudotumor-like follicular dendritic cell sarcoma of the liver. Rev Esp Enferm Dig. 2021;113(5):378–9. 10.17235/reed.2020.7602/2020.
Zhao M, Du X, OuYang B, Li M, Yang H. Inflammatory pseudotumor-like follicular dendritic cell sarcoma mimicking a colonic polyp. J Gastrointest Surg. 2021;25(9):2429–30. 10.1007/s11605-021-04961-y.
Pagliuca F, Ronchi A, Auricchio A, Lieto E, Franco R. Inflammatory pseudotumor-like follicular/fibroblastic dendritic cell sarcoma: focus on immunohistochemical profile and association with Epstein-Barr virus. Infect Agent Cancer. 2022;17(1):63. 10.1186/s13027-022-00474-8.
Bui PL, Vicens RA, Westin JR, Jensen CT. Multimodality imaging of Epstein-Barr virus-associated inflammatory pseudotumor-like follicular dendritic cell tumor of the spleen: case report and literature review. Clin Imaging. 2015;39(3):525–8. 10.1016/j.clinimag.2014.12.021.
Xue N, Xue X, Sheng C, Lu M, Wang Y, Zhang S, Xu Y. Imaging features of inflammatory pseudotumor-like follicular dendritic cell sarcoma of the spleen. Ann Palliat Med. 2021;10(12):12140–8. 10.21037/apm-21-2776.
Chen F, Li J, Xie P. Imaging and pathological comparison of inflammatory pseudotumor-like follicular dendritic cell sarcoma of the spleen: A case report and literature review. Front Surg. 2022;9:973106. 10.3389/fsurg.2022.973106.
Corvino A, Catalano O, Corvino F, Petrillo A. Rectal melanoma presenting as a solitary complex cystic liver lesion: role of contrast-specific low-MI real-time ultrasound imaging. J Ultrasound. 2016;19(2):135–9. 10.1007/s40477-015-0182-1.
Yan S, Yue Z, Zhang P, Yuan L, Wang H, Yin F, Ju L, Chen L, Cai W, Ni Y, Wu J. Case report: Hepatic inflammatory pseudotumor-like follicular dendritic cell sarcoma: a rare case and review of the literature. Front Med (Lausanne). 2023;10:1192998. 10.3389/fmed.2023.1192998.
Xu L, Ge R, Gao S. Imaging features and radiologic-pathologic correlations of inflammatory pseudotumor-like follicular dendritic cell sarcoma. BMC Med Imaging. 2021;21(1):52. 10.1186/s12880-021-00584-6.

No competing interests reported.

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Clinicopathological and Imaging Characteristics of EBV Positive Inflammatory Follicular Dendritic Cell Sarcoma

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Pathologic Evaluation

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MRI Findings

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