Extraskeletal osteosarcoma infiltrating pancreas, spleen, gastric, and left kidney: a case report.

BACKGROUND: Extraskeletal osteosarcoma is an extremely rare malignancy that accounts for 1% of soft tissue sarcoma and 4.3% of all osteosarcoma. Extraskeletal osteosarcoma can develop in a patient between the ages of 48 and 60 years. The incidence of extraskeletal osteosarcoma is slightly higher in male patients than in females. CASE PRESENTATION: A 50-year-old Caucasian male patient presented with a 6-month history of intermittent lower-left back pain that limits his activity. Prior ultrasonography and abdominal computed tomography scan showed a diagnosis of kidney stone and tumor in the lower-left abdomen. The computed tomography urography with contrast revealed a mass suspected as a left retroperitoneal malignant tumor. Hence, the tumor was resected through laparotomy and the patient continued with histopathological and immunohistochemistry examination with the result of extraskeletal osteosarcoma. CONCLUSION: Extraskeletal osteosarcoma presents diagnostic challenges requiring multimodal examination, including histological and immunohistochemistry analyses. This case underscores the aggressive nature and poor prognosis despite undergoing the current suggested treatment.

Differentiating malignant from benign splenic lesions: a meta-analysis and pictorial review of imaging features.

OBJECTIVES: Splenic lesions might exhibit overlapping imaging features, varying from benign entities like cysts and hemangiomas to malignancies such as lymphoma and angiosarcoma. This meta-analysis aims to delineate imaging characteristics that distinguish malignant from benign splenic lesions. METHODS: Adhering to PRISMA guidelines, we searched PubMed, Scopus, and Web of Science for studies on imaging features differentiating malignant from benign splenic lesions. We extracted data on splenic pathology and imaging characteristics and assessed the methodological quality via QUADAS-2. Odds ratio meta-analyses were performed using STATA (Version 17.0, Stata Corp, College Station, TX). RESULTS: Portal phase hypoenhancement, hypovascular enhancement pattern, diffusion restriction, and late phase hypoenhancement, with odds ratios above 10, highly indicate malignancy. Other features suggestive of malignancy include solid morphology, lymphadenopathy, presence of perisplenic fluid, arterial hypoenhancement, hypoechogenicity on ultrasound, splenomegaly, and presence of multiple lesions. In contrast, cystic morphology, hypervascular-washout and hypervascular-persistent pattern of enhancement, late phase hyperenhancement, anechogenicity on ultrasound, portal phase hyperenhancement, well-defined borders, and calcification are in favour of benign pathology. CONCLUSION: The study underscores the critical role of contrast-enhanced and diffusion-weighted imaging in distinguishing malignant from benign splenic lesions, emphasizing the role of features like portal phase hypoenhancement and restricted diffusion in diagnosing malignancies. Additionally, the study emphasizes the value of contrast-enhanced ultrasound, which allows for the visualization of key contrast-enhancement patterns without the risk of ionizing radiation exposure.

Imaging findings of Epstein-Barr Virus-positive inflammatory follicular dendritic cell sarcoma of spleen: A case report.

BACKGROUND: Spleen Epstein-Barr Virus (EBV)-positive inflammatory follicular dendritic cell sarcoma (FDCS) is rare, and the imaging signs are unclear. The COVID-19 has been confirmed to be the cause of pneumonia and can cause a variety of diseases including myocarditis. However, it has not been reported to be the cause of the exacerbation or activation of EBV-positive inflammatory FDCS. OBJECTIVE: The objective is to extract the imaging features of EBV-positive inflammatory FDCS in the spleen and analyze the reasons for the special features of this case. METHODS: By analyzing the patient's treatment process and imaging examinations (A 77-year-old female was admitted to the hospital due to generalized discomfort and pain symptoms. When she was admitted to the hospital a year earlier with COVID-19 pneumonia, a chest CT scan showed that she had a splenic tumor. During this admission, CT scans showed two irregularly shaped and unevenly dense soft tissue density masses within the spleen, with uneven enhancement on contrast-enhanced im-aging within the solid components and along the edges. PET/CT scans revealed elevated glucose metabolism in the masses. Postoperative pathological diagnosis confirmed splenic EBV-positive inflammatory FDCS.), reading the literature, sorting out the disease cognitive process, epidemiology, and pathological data of EBV-positive inflammatory FDCS, we discussed the imaging manifestations and possible differential diagnosis of the disease. RESULTS: The patient was finally diagnosed with splenic EBV-positive inflammatory FDCS. CONCLUSIONS: Imaging features of EBV-positive inflammatory FDCS in the spleen include a high incidence of hemorrhage and necrosis, persistent moderate enhancement of the solid portion, a "capsular-like enhancement" structure at the tumor edge, and possibly active glucose metabolism with high Standardized Uptake Values (SUVs). COVID-19 infection and long-term COVID-19 sequelae may exacerbate and activate EBV-positive inflammatory FDCS in the spleen, and the mechanism remains to be further studied.

Atypically located accessory splenic hemangiosarcoma in a Dog: Diagnostic value of triple-phase computed tomography.

A 10-year-old Cocker spaniel presented with lethargy. Triple-phase computed tomography was obtained with a contrast test bolus at the level of porta hepatis, which revealed a right lower abdominal mass. The mass was not connected to other abdominal organs; however, a linear structure was observed connecting the splenic hilum to the mass, which was suspected to be the feeding vessel. The arterial phase image was obtained again with a contrast bolus at the level of the celiac artery. A prominent contrast-enhanced feeding artery originating from the splenic artery to the mass was observed. Histopathology confirmed an accessory splenic hemangiosarcoma.

Incidental Detection of Synchronous Benign Hepatic and Splenic Hemangiomas on 18 F-PSMA PET/CT.

ABSTRACT: A 51-year-old man with biochemical failure after brachytherapy for prostatic adenocarcinoma (PSA 5 µg/L rising to 6.45 µg/L) underwent a PSMA PET/CT scan. The scan revealed focal 18 F-PSMA activity at the right apex suggestive of local residual or recurrent disease. In addition, 18 F-PSMA images demonstrated 2 focal 18 F-PSMA-avid liver and spleen lesions; both lesions were further evaluated by abdominal MRI, and the final radiological diagnosis was synchronous hepatic and splenic hemangiomas.

Littoral cell angioma of the spleen: A study of 10 cases case series and literature review.

BACKGROUND: Current study aimed to investigate the clinical characterization, differential diagnosis, and treatment of splenic littoral cell angioma (LCA). METHODS: A retrospective analysis was performed for 10 LCA cases admitted to Huzhou Central Hospital from 2007 to 2023, for clinical manifestations, hematological tests, imaging features, pathological features, treatment methods, and prognosis along with the relevant literature was also reviewed. RESULTS: During examinations, no specific clinical manifestations and hematological abnormalities were seen in all 10 cases of LCA. Imaging observations depicted single or even multiple spherical lesions in the spleen. Plains shown by computed tomography (CT) were found somewhat equal or slightly lower in density. On the other hand, magnetic resonance imaging (MRI) plain scans viz. T1 weighted image showed equal low and mixed signals while T2-weighted showed high and low mixed signals. Moreover, punctate low signals could be seen in high signals named "freckle sign" in MRI scans. On contrast-enhanced CT scans, the enhancement of the lesions was not obvious in the arterial phase, and some of the lesions showed edged ring-like enhancements and "filling lake" progressive enhancement during the venous phase and delayed phase. In multiple lesions, the number of enhanced scan lesions showed a variable changing pattern "less-more-less." MRI-enhanced scan showed the characteristics of "fast in and slow out." Microscopic examinations identified tumor tissue actually composed of sinus-like lacunae that anastomosed with each other in the form of a network. Furthermore, cystic expansion and pseudopapillary protrusions were also seen in the dilated sinus cavity which was lined with single-layer endothelial cells having conspicuous cytoplasmic hemosiderin. High immunophenotypic expressions of vascular endothelial cell phenotype (CD31, CD34, FVIII) and tissue cell phenotype (CD68) were also seen. Total and partial splenectomy were performed in 8 and 2 patients, respectively, and follow-up examinations showed survival in all patients with no recurrence. CONCLUSION: LCA is a rare splenic benign lesion with atypical clinical manifestations. CT and MRI imaging are important tools in preoperative diagnosis based on pathomorphological and immunohistochemical examinations. Splenectomy is a superior therapeutic choice with significant impacts and prognosis.

Littoral cell angioma of the spleen: case report and literature review.

Littoral cell angioma is an extremely rare splenic vascular tumor originating from the cells lining the splenic red pulp sinuses. Approximately 150 cases of littoral cell angioma have been reported since 1991. Its clinical manifestation is usually asymptomatic and is mostly diagnosed as an incidental finding through abdominal imaging. Herein, we present a case of littoral cell angioma in a 41-year-old woman with no previous comorbidities, which initially presented as a nonspecific splenic lesion diagnosed on imaging in the emergency room. The patient was treated through laparoscopic intervention.

Sclerosing angiomatoid nodular transformation of spleen: A rare case report.

ABSTRACT: Sclerosing angiomatoid nodular transformation (SANT) is a reactive non-neoplastic, rare vascular lesion of the spleen. The histology shows multiple angiomatoid nodules surrounded by proliferative stroma. A 31-year-old lady presented with an abdominal mass for 6 months. Contrast-enhanced computed tomography (CECT) abdomen was suggestive of hemangiopericytoma/hemangioendothelioma. An open splenectomy was performed, and the resected specimen was sent for histopathology examination. The gross examination showed a bosselated mass present at the lower pole of the spleen measuring 8 × 8 cm with peripherally located coalescing red-brown nodules embedded in a dense fibrous stroma on the cut surface. On microscopy, multiple circumscribed angiomatoid nodules comprising irregular slit-like vascular channels lined by plump endothelial cells were seen embedded in dense sclerotic stroma. Because of the lack of specific diagnostic features, it is difficult to diagnose SANT clinically and radiologically. However, the typical histopathological findings are a clue in clinching the diagnosis.

A case of multifocal sclerosis angiomatoid nodular transformations of the spleen occurring after partial splenic infarction with transcatheter arterial embolization for splenic artery aneurysm.

A 48-year-old woman underwent transcatheter arterial embolization (TAE) for a splenic artery aneurysm, which resulted in a partial splenic infarction in the middle lobe. Five years after TAE, a 20-mm diameter mass in the noninfarcted area of the spleen was detected on imaging, which grew to 25 mm in diameter after 6 months. MRI after gadolinium administration showed a 35 × 34 mm mass within the superior pole and 15 × 12 mm mass within the inferior pole. The patient underwent laparoscopic splenectomy and had an uneventful postoperative recovery. No evidence of recurrence was observed during the 2-year follow-up period after surgery. The mass was pathologically confirmed to be sclerosing angiomatoid nodular transformation (SANT) of the spleen. While some studies hypothesize that SANT is a response to vascular injury or trauma, to the best of our knowledge, there have been no previous reports of SANT occurring after procedures directly affecting splenic blood flow. Additionally, multifocal SANTs are reported to be very rare, accounting for only 4.7% of all reported SANTs of the spleen. We highlight a rare course of SANT of the spleen and discuss the possible relationship between blood flow abnormalities and the appearance of SANT.

Intense 18 F-PSMA-1007 Uptake of Splenic Hemangioma.

ABSTRACT: A 77-year-old man was referred for 18 F-PSMA-1007 PET/CT scan for initial staging of biopsy-proved prostate adenocarcinoma. 18 F-PSMA-1007 PET/CT showed focal intense 18 F-PSMA-1007 of the prostate adenocarcinoma and a focal intense activity (SUV max , 27) in the spleen. The 18 F-PSMA-1007-avid splenic lesion corresponded to a splenic hemangioma, which was initially detected on contrast-enhanced CT 7 months ago and unchanged in size and enhancement pattern on follow-up contrast-enhanced CT. This case indicates that splenic hemangioma should be included in the differential diagnosis of PSMA-avid splenic lesions.

Laparoscopic partial splenectomy in a patient with splenic hemangioma after distal gastrectomy for a neuroendocrine tumor.

Herein, we report the case of a patient with splenic hemangioma after distal gastrectomy who was treated with laparoscopic partial splenectomy. A 64-year-old woman previously underwent laparoscopic distal gastrectomy with regional lymph-node dissection for a gastric neuroendocrine tumor (G3) with venous infiltration and no lymph-node metastases. Periodic follow-up abdominal computed tomography revealed a well-defined, heterogeneous mass in the lower pole of the spleen 5 years after the operation, which grew from 12 to 19 mm 1 year later. A laparoscopic partial splenectomy was planned. During surgery, a smooth-surfaced mass with a lighter color than that of the surrounding area was observed at the lower pole of the spleen. The inferior polar branch of the splenic artery was transected, and the ischemic area of the lower pole of the spleen, where the tumor was present, was confirmed. First, the line used to perform splenic transection was determined using soft coagulation. The splenic parenchyma was then gradually transected using a vessel-sealing device system, and partial splenectomy was possible with almost no bleeding. The patient was discharged on postoperative day 8 without any complications. Pathological examination revealed a hemangioma without any malignant findings. Laparoscopic partial splenectomy is a safe and useful procedure that can be performed, considering the tumor size and location.

Exploration of predictors associated with bleeding in computed tomography-guided core needle splenic biopsy: A retrospective study.

Splenic diseases may be caused by infections and can be either malignant, such as lymphoma and lung cancer, or benign, such as hemangioma. In some cases, diagnostic uncertainty of imaging persists, and image-guided splenic needle biopsy is a useful diagnostic tool to avoid the disadvantages of incorrect diagnosis, including performing unnecessary splenectomy or not giving the necessary treatment. Splenic biopsies can be divided into ultrasound-guided, computed tomography (CT)-guided fine-needle aspiration, or core needle biopsy (CNB). However, few studies have focused exclusively on complications associated with CT-guided CNB of the spleen. Therefore, we assessed bleeding, the most common complication of CT-guided CNB of the spleen, and evaluated factors associated with the bleeding. Using the biopsy database maintained at the institution, all patients who underwent CT-guided CNB of the spleen between May 2012 and September 2022 were identified retrospectively. The 18 identified patients were divided into post-biopsy bleeding and non-bleeding groups for analysis. In total, 17 patients (94.4%) could be diagnosed accurately with CT-guided CNB. Bleeding complications occurred in 7 cases of CT-guided CNB; of these, 2 patients with Common Terminology Criteria for Adverse Events grade 4 disease required transcatheter arterial embolization. The bleeding group was characterized by diffuse spleen tumors in all cases, with significantly more diffuse spleen tumors than the non-bleeding group. CT-guided CNB is a useful option for neoplastic lesions of the spleen that are difficult to diagnose using imaging alone. However, consideration should be given to post-biopsy bleeding in patients with diffuse splenic tumors.

[Multimodal ultrasound techniques for the differential diagnosis of splenic lesions - A diagnostic challenge]. / Multimodale Ultraschalltechniken zur Differenzialdiagnose von Milzherden ­ eine diagnostische Herausforderung.

BACKGROUND: Splenic tumors are rare and can pose a differential diagnostic challenge, especially as an incidental imaging finding. Due to a lack of large scale biopsy studies the available literature is limited with respect to clear imaging criteria for dignity. OBJECTIVE: The present work is intended to show the chances of a targeted elicitation of the medical history as well as the possibilities and limitations of multimodal sonography in order to achieve the correct diagnosis of a splenic lesion using simple and gentle methods. MATERIAL AND METHODS: Selective literature search and clinical case studies. RESULTS: In the differential diagnostics of focal splenic lesions, information about pre-existing hemato-oncological or inflammatory rheumatological diseases is essential in order to correctly classify incidental findings in particular. In addition to B­mode ultrasound (B-US) and color-coded Doppler ultrasound (CD-US), contrast-enhanced ultrasound (CEUS) in particular provides crucial differential diagnostic information. While hyperechoic foci in B­US or arterially hypervascularized splenic foci in CD-US/CEUS are usually benign, hypoechoic and arterially hypoperfused foci in CD-US/CEUS must be further clarified. Although the ultrasound-guided biopsy of the spleen has a higher risk of bleeding than a liver biopsy, it is still the gentlest and most effective method for achieving the histological clarification of splenic lesions when the indications are correct. CONCLUSION: Through the combination of the medical history and multimodal ultrasound methods, if necessary supplemented by an ultrasound-guided biopsy, focal splenic lesions can be successfully classified in most cases with a direct impact on further clinical procedures.

[Surgery for primary splenic tumors and metastases of the spleen]. / Chirurgie bei primären Milztumoren und Metastasen der Milz.

The correct indications for surgical treatment of primary splenic tumors as well as metastases of the spleen are challenging due to the rarity of the various entities. Primary solid splenic tumors include benign lesions, such as hemangiomas, hamartomas and sclerosing angiomatous nodular transformation (SANT) of the spleen. In these cases, surgical treatment is indicated only in the case of inconclusive imaging and after careful consideration of the risk-benefit ratio, even in the case of pronounced symptoms. In contrast, primary angiosarcoma or undifferentiated pleomorphic sarcoma as highly malignant tumors represent an urgent indication for surgery. Although more frequent than primary splenic malignancies, secondary splenic tumors are also not that frequent. Solitary splenic metastases are rare; however, from an oncological point of view they can be treated by resection. In the case of oligometastasis with splenic involvement, splenectomy is used only as part of a palliative concept in cases of pronounced symptoms or in the context of cytoreductive surgery. In general, the laparoscopic approach is to be preferred when the operation is technically feasible as it is associated with fewer pulmonary and infectious complications and a shorter hospital stay. In addition, to reduce the risk of severe infections after splenectomy, the option of partial splenectomy should be considered, especially for benign lesions. A thorough informing of the patient regarding both intraoperative and perioperative risks as well as potential long-term sequelae, especially severe infectious diseases, is an essential component of informed consent before surgery.

False-Positive Uptake in Splenic Hemangioma on 68 Ga-DOTATATE PET/CT.

ABSTRACT: Somatostatin receptor imaging using 68 Ga-DOTATATE PET is widely popular for evaluation of neuroendocrine tumors. 68 Ga-DOTATATE PET/CT shows highest physiologic uptake in spleen followed by other organs such as kidneys, adrenal glands, and liver. Hemangiomas, although rare, are the most common primary benign neoplasm of the spleen, composed of endothelial-lined vascular channels. We present a case of 77-year-old man who underwent 68 Ga-DOTATATE PET/CT scan for evaluation of pancreatic neuroendocrine tumor and incidentally demonstrated intense radiotracer uptake in splenic hemangiomata.

Can CT texture analysis parameters be used as imaging biomarkers for prediction of malignancy in canine splenic tumors?

Splenic hemangiosarcoma has morphological similarities to benign nodular hyperplasia. Computed tomography (CT) texture analysis can analyze the texture of images that the naive human eye cannot detect. Recently, there have been attempts to incorporate CT texture analysis with artificial intelligence in human medicine. This retrospective, analytical design study aimed to assess the feasibility of CT texture analysis in splenic masses and investigate predictive biomarkers of splenic hemangiosarcoma in dogs. Parameters for dogs with hemangiosarcoma and nodular hyperplasia were compared, and an independent parameter that could differentiate between them was selected. Discriminant analysis was performed to assess the ability to discriminate the two splenic masses and compare the relative importance of the parameters. A total of 23 dogs were sampled, including 16 splenic nodular hyperplasia and seven hemangiosarcoma. In each dog, total 38 radiomic parameters were extracted from first-, second-, and higher-order matrices. Thirteen parameters had significant differences between hemangiosarcoma and nodular hyperplasia. Skewness in the first-order matrix and GLRLM_LGRE and GLZLM_ZLNU in the second, higher-order matrix were determined as independent parameters. A discriminant equation consisting of skewness, GLZLM_LGZE, and GLZLM_ZLNU was derived, and the cross-validation verification result showed an accuracy of 95.7%. Skewness was the most influential parameter for the discrimination of the two masses. The study results supported using CT texture analysis to help differentiate hemangiosarcoma from nodular hyperplasia in dogs. This new diagnostic approach can be used for developing future machine learning-based texture analysis tools.

Solitary Splenic Metastasis From Endometrial Carcinoma Revealed on FDG PET/CT.

ABSTRACT: Solitary splenic metastasis from endometrial carcinoma is rare. We report a case of imaging findings of solitary splenic metastasis in a 53-year-old woman who underwent resection surgery of endometrial carcinoma of uterus 1 year ago. On FDG PET/CT, it presented as a solitary soft tissue mass with an SUVmax of 18.44. The postoperative pathology supported metastasis from endometrial carcinoma.