Sclerosing angiomatoid nodular transformation of the spleen: CT and MRI features with pathologic correlation. AJR Am J Roentgenol. 2013;200:W353-W360. [PMID: 23521478 DOI: 10.2214/ajr.12.9522]

Sclerosing angiomatoid nodular transformation of the spleen: Case reports and literature review

RATIONALE

Sclerosing angiomatoid nodular transformation (SANT) of the spleen is an uncommon benign vascular lesion with an obscure etiology. It predominantly affects middle-aged women and presents with nonspecific clinical signs, making preoperative diagnosis challenging. The definitive diagnosis of SANT relies on pathological examination following splenectomy. This study aims to contribute to the understanding of SANT by presenting a case series and reviewing the literature to highlight the clinical presentation, diagnostic challenges, and treatment outcomes.

PATIENT CONCERNS

In this retrospective study, we analyzed the clinical data of 3 patients with confirmed SANT admitted from November 2013 to October 2023. The cases include a 25-year-old male, a 15-year-old female, and a 39-year-old male, each with a splenic mass.

DIAGNOSES AND INTERVENTIONS

All of the three cases were treated by laparoscopic splenectomy (LS). Pathological examination confirmed SANT in all cases.

OUTCOMES

No recurrence or metastasis was observed during a 10-year follow-up for the first 2 cases, and the third case showed no abnormalities at 2 months postoperatively. Despite its rarity, SANT is a significant condition due to its potential for misdiagnosis and the importance of distinguishing it from malignant lesions. The study underscores the utility of LS as a safe and effective treatment option.

LESSONS

SANT is a rare benign tumor of the spleen, and the preoperative diagnosis of whom is challenging. LS is a safe and effective treatment for SANT, with satisfactory surgical outcomes and favorable long-term prognosis on follow-up. The study contributes to the limited body of research on this rare condition and calls for larger studies to validate these findings and improve clinical management.

Sclerosing Angiomatoid Nodular Transformation of the Spleen: Radiological Findings and Radiological-pathological Correlation

Introduction

The objective of this study was to describe the CT and MRI features of sclerosing angiomatoid nodular transformation (SANT) of the spleen with pathologic correlation.

Materials and Methods

Ten patients with surgically resected and pathologically confirmed SANTs were included. Clinical history was reviewed, and gross pathologic, histologic, and immunohistochemical findings were recorded. CT and MRI examinations were evaluated by two radiologists.

Results

Patients included seven men and three women, with a mean age of 42.9±16.7 years. Pathologic features of SANTs involved multiple angiomatous nodules in a radiating pattern with a central stellate fibrous scar and evidence of hemosiderin deposition. 9 cases showed a lobulated demarcated margin, 8 cases a slight hypoattenuating, 1 isoattenuating, and 1 case with two lesions demonstrated a slight hyperattenuating margin, respectively. Multiple scattered punctate calcifications were involved in 2 cases. 5 cases manifested hypointensity on in-phase imaging, 1 iso-intensity, and 4 iso-hypointensity on out-of-phase imaging. Progressive and centripetal enhancement were exhibited in 10 cases, spoke-wheel pattern in 3 cases, and nodular enhancement in 4 cases, respectively. The central fibrous scar was identified in 8 cases during delayed enhancement.

Conclusion

Characteristics of SANTs on CT/MRI reflected the underlying pathology. Hypointensity on DWI and T2WI, and change of signal on T1 chemicalshift imaging were found to be due to hemosiderin deposition and fibrous tissue. Typical feature was a solitary, round, lobulated mass with a fibrous scar. Progressive and centripetal enhancement, spoke-wheel pattern, nodular enhancement, and delayed enhancement of central fibrous scar were observed.

Sclerosing angiomatoid nodular transformation of the spleen in a child with anemia: a case report and review of the literature

BACKGROUND

Sclerosing angiomatoid nodular transformation of the spleen is a relatively rare benign vascular lesion in both adult and pediatric age groups with unclear etiopathogenesis and variable clinical presentations. Many benign and also malignant splenic masses could mimic sclerosing angiomatoid nodular transformation, both clinically and radiologically. Herein, we report our experience with a case of sclerosing angiomatoid nodular transformation in a 3-year-old girl.

CASE REPORT

A 3-year-old Iranian girl presented with abdominal pain, back pain, and constipation for 2 weeks. She was being followed up by a pediatrician due to her short stature and persistent anemia. Physical examination showed stable vital signs, short stature, pallor, and a puffy face. Laboratory evaluation showed normochromic normocytic anemia with a normal reticulocyte count, ferritin, and hemoglobin electrophoresis. Radiologic assessments revealed a hypoechoic lesion in the spleen with high vascularity, clinically suspected to be lymphoma. She was operated on, and after partial splenectomy, pathologic evaluation of the spleen showed a solitary, well-demarcated, and unencapsulated dark mass. Microscopic examination revealed micronodular appearance composed of irregular-shaped vascular spaces lined by plump endothelial cells and surrounded by concentric collagen fibers, features in keeping with sclerosing angiomatoid nodular transformation. The patient's anemia was resolved after surgery, and no clinical or radiologic deficits were noted during the 10-month follow-up visits.

CONCLUSION

Although sclerosing angiomatoid nodular transformation is exceedingly rare in children, it should be considered a differential diagnosis in pediatric splenic neoplasms with concurrent hematologic manifestations, such as anemia.

Sclerosing angiomatoid nodular transformation of the spleen: multimodality imaging features and literature review

OBJECTIVE

The purpose of this study was to evaluate the CT and MRI findings, clinicopathologic features, and differential diagnosis of Sclerosing angiomatoid nodular transformation (SANT).

METHODS AND MATERIALS

Seven men and seven women with pathological diagnoses of SANT were included in this retrospect study. Patients underwent at least one radiological examination before surgery. The number, shape, margin, size, attenuation, signal intensity, homogeneity, and enhancing pattern of the lesion were evaluated by two abdominal radiologists independently. Immunohistochemistry reports were available for 11 patients. The immunoreactivity to the vascular markers CD8, CD31, and CD34 was assessed.

RESULTS

The 14 SANT patients (7 men, 7 women; mean age, 43.5 years; age range, 24-56 years) presented with a single lesion and showed no specific clinical symptoms. Among 14 patients, 12 patients underwent MR scan, 5 patients underwent CT scan and 3 patients underwent PET-CT. On CT, all 5 lesions showed hypodensity on non-contrast images and spoke-wheel enhancing pattern after contrast administration, and calcification was observed. On T2WI, 10 cases(83.3%)showed hypointensity and 2 cases (16.7%) showed hyperintensity with central hypointensity. On T1WI, 10 cases (83.3%) were isointense and 2 cases (16.7%) were slightly hypointense. 10 cases (83.3%) showed hypointensity on DWI and 2 cases (16.7%) showed slightly hyperintensity on DWI. After contrast administration, all 12 lesions showed progressive enhancement. 18 F-fluorodeoxyglucose (FDG) uptake in the tumor was seen in all three cases that underwent PET-CT. The maximum standardized uptake value (SUVmax) was 4.5, 5.1, and 3.8 respectively.

RESULTS

Apart from the progressive spoke-wheel enhancing pattern, DWI and ADC findings will add value to the diagnosis of SANT.

Algorithmic Approach to the Splenic Lesion Based on Radiologic-Pathologic Correlation

Splenic lesions are commonly discovered incidentally at imaging, without clinical signs or symptoms that may aid in diagnosis. As such, the differential diagnosis and subsequent management are based primarily on imaging characteristics. Much has been written about the myriad pathologic conditions that can occur in the spleen; however, there is little guidance on the approach to an incidental splenic mass. Applying an approach frequently used in imaging to the splenic mass-based on the number and consistency of lesions and refined by supplementary imaging features-allows formulation of a useful differential diagnosis. Solitary cystic masses include true cysts, pseudocysts, and parasitic cysts. When multiple cystic lesions are present, the differential diagnosis expands to include infectious lesions (abscess or microabscesses) and lymphangioma (a benign cystic neoplasm). Hemangioma is the most common solitary solid mass, although other vascular lesions (hamartoma, sclerosing angiomatoid nodular transformation) and nonvascular lesions (inflammatory pseudotumor, lymphoma) manifest as solitary and solid. When multiple solid masses are present, diffuse inflammatory disease (sarcoidosis), littoral cell angioma, and lymphoma should be considered. Malignancies, such as angiosarcoma or metastasis, can manifest as solitary or multiple and solid or cystic masses but are typically associated with symptoms or widespread primary malignancy. Careful assessment of the multimodality imaging characteristics of splenic lesions based on this approach aids the radiologist faced with the incidental splenic lesion. Online supplemental material is available for this article. Work of the U.S. Government published under an exclusive license with the RSNA.

Sclerosing Angiomatoid Nodular Transformation of the Spleen: A Diagnostic Conundrum

A splenic lesion often represents a diagnostic challenge due to relative scarcity and the broad differential diagnosis. Sclerosing Angiomatoid Nodular Transformation (SANT) of the spleen is usually encountered only incidentally. Although benign, patients with SANT often receive splenectomy, due to its rarity, diagnostic uncertainty and sometimes intimidating imaging morphology and size. Imaging features on computed tomography, magnetic resonance and positron emission tomography have a high diagnostic value for SANT and help differentiate this entity from other splenic lesions. When the imaging parameters are matched with core needle biopsy tissue analysis, further watchful waiting can be recommended in order to avoid splenectomy.

Ultrasonographic atlas of splenic lesions

Ultrasonography (US) is widely used for abdominal imaging. Its noninvasiveness, extensive range of application, and low cost make US a useful and valuable tool for the detection, diagnosis, and follow-up of splenic abnormalities. Concomitantly with the increasing frequency of imaging, more splenic lesions are being discovered and the requirements for the differential diagnosis are rising. In this pictorial essay, we introduce the representative US findings of many different splenic lesions, including normal sonographic findings, normal variants and congenital anomalies, infectious conditions, benign and malignant neoplasms, and non-neoplastic lesions. Knowledge of the US features of various splenic lesions will help narrow the differential diagnosis and guide clinical decision-making.

Sclerosing angiomatoid nodular transformation of the spleen: a case report

Sclerosing angiomatoid nodular transformation (SANT) of the spleen is an uncommon primary benign condition with specific histopathological characteristics. The majority of the patients are usually asymptomatic and present for treatment after an incidental finding on a routine abdominal imaging. The differential diagnosis includes other benign tumours, as well as primary malignancy or metastases of unknown origin. We report a 55-year-old woman who was presented to the surgical team of our hospital for splenectomy after the investigation of an incidental splenic lesion led to the diagnosis of SANT. The pathology report of the specimen repeated the initial diagnosis. The patient has not yet presented any complication or recurrence of the disease 8 months after the operation. From such infrequent cases, the most valuable conclusion which can be yielded is that the more the number of patients reported, the more the knowledge about the disease is broadened.

WFUMB Position Paper-Incidental Findings, How to Manage: Spleen

The World Federation for Ultrasound in Medicine and Biology (WFUMB) is addressing the issue of incidental findings (IFs) with a series of publications entitled "Incidental Imaging Findings-The Role of Medical Ultrasound." IFs are less commonly encountered in the spleen than in many other abdominal organs but remain a frequent dilemma in clinical practice. A histological diagnosis is rarely necessary for patient management. Many IFs, such as secondary spleens and splenic cysts, are harmless and do not require any further investigation. The diagnosis of many other focal splenic lesions is, however, often problematic. The following overview is intended to illustrate a variety of incidentally detected spleen pathologies such as size variants, shape variants, secondary spleens, focal splenic lesions and splenic calcifications. It should aid the examiner in establishing the diagnosis. Moreover, it should help the ultrasound practitioner decide which pathologies need no further investigation, those requiring interval imaging and cases in which immediate further diagnostic procedures are required.

Incidental Splenic Findings on Cross-Sectional Imaging

Incidental splenic focal findings are commonly encountered in clinical practice and frequently represent a diagnostic dilemma due to nonspecific imaging features. Most are benign, particularly in patients without a history of malignancy and without symptoms of fever, weight loss, or left upper quadrant or epigastric pain. Incidental malignant splenic processes are exceedingly rare. This article reviews imaging characteristics of incidental focal splenic findings, and proposes a practical approach for management of such findings, which can prevent unnecessary workup and its related drawbacks in clinical practice.

Revisiting the Spleen—An Imaging Review of the Common and Uncommon Splenic Pathology

The spleen is the largest lymphatic organ and is responsible for both hematological and immunological functions. Several common etiologies such as trauma, developmental variants, infectious/inflammatory conditions, and benign and malignant lesions can occur in the spleen. The role of imaging modalities such as ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI) in diagnosing these conditions continues to evolve. The main objective of this review article is to illustrate the role of imaging in identifying the common and uncommon pathology of the spleen.

Iron-containing pathologies of the spleen: magnetic resonance imaging features with pathologic correlation

Systemic and non-systemic pathologies that involve iron deposition within the spleen have characteristic features on MRI due to the susceptibility properties of deposited iron, or hemosiderin. These lesions will have signal loss on longer echo sequences due to the T2* effect when evaluated with dual-echo gradient-echo sequences. The pathophysiology of systemic and localized iron sequestration disease processes can elucidate an underlying diagnosis based on these imaging features in conjunction with clinical information.

Septic shock due to Granulicatella adiacens after endoscopic ultrasound-guided biopsy of a splenic mass: A case report

BACKGROUND

Endoscopic ultrasound-guided fine needle aspiration or biopsy (EUS-FNA or FNB) has become a popular method for diagnosing various lesions of the gastrointestinal tract and surrounding tissue due to the accuracy and safety. To the best of our knowledge, no case report of severe infection after EUS-FNB of a solid lesion in the spleen has been described. Herein, we report a rare case of septic shock after EUS-FNB of a splenic mass.

CASE SUMMARY

A 45-year-old male patient presented to the outpatient clinic due to an incidentally detected splenic mass. A definitive diagnosis could not be established based on the abdominal magnetic resonance imaging. EUS of the spleen showed a 6 cm-sized, relatively well-demarcated, heterogeneous mass, and EUS-FNB with a 22G needle was performed. Ten days after the procedure patient developed septic shock and a splenic abscess was identified. Blood culture revealed growth of Granulicatella adiacens. After the treatment with antibiotics the patient underwent surgical resection, and the pathological examination showed diffuse large B-cell lymphoma. The patient received chemotherapy and he is in complete remission.

CONCLUSION

Infection of a splenic mass after EUS-FNB is a rare complication and prophylactic antibiotics might be considered.

CT and MRI features of sclerosing angiomatoid nodular transformation of the spleen: A report of 18 patients with pathologic correlation

PURPOSE

The purpose of this study was to describe the computed tomography (CT) and magnetic resonance imaging (MRI) features of sclerosing angiomatoid nodular transformation (SANT) of the spleen and correlate imaging features with those obtained at histopathologic analysis.

MATERIALS AND METHODS

A total of 18 patients (9 men, 9 women; mean age, 42.2±10.7 [standard deviation (SD)] years; range, 23-59 years) with histopathologically confirmed SANT were retrospectively evaluated. The presenting symptoms, gross pathologic changes, and histopathologic and correlative immunohistochemical results were recorded. CT (n=8) and MRI (n=12) features were analyzed by two radiologists and included number, size, shape, boundary, attenuation, signal intensity, and enhancement patterns.

RESULTS

Seventeen patients (17/18; 94%) had a single SANT without specific clinical symptoms and one patient (1/18; 6%) had multiple SANTs with left-upper-quadrant bloating and pain. The largest lesion diameter exceeded 3cm. On plain CT images, SANTs were slightly hypoattenuating in seven patients (7/8; 88%), isoattenuating in one patient (1/8; 13%), and contained calcification in two patients (2/8; 25%). On T2-weighted MR images, SANTs displayed hypointensity in ten patients (10/12; 83.3%), isointensity in one patient (1/12; 8%) and hyperintensity in one patient (1/12; 8%). On T2-weighted images, stellate or scattered fibrous scars were observed in all patients (12/12; 100%). On diffusion-weighted images, SANTs appeared as heterogenous or homogeneous hypointense in 12 patients (12/12; 100%). Compared to out-of-phase images, SANTs displayed decreased local signal intensity on in-phase images in 12 patients (12/12; 100%). On enhanced CT and MRI images, SANTs had clear boundaries (17/18; 94%), oval (7/18; 39%) or lobular (7/18; 39%) shape, displayed progressive centripetal enhancement (18/18; 100%), spoke-wheel pattern (14/18; 78%), nodular enhancement (11/18; 61%), or delayed enhancement of central fibrous scar (9/18; 50%).

CONCLUSIONS

SANT of the spleen predominantly manifests as a solid, single, oval or lobular, and well-defined lesion with a fibrous scar and occasional calcification. Typical enhancement characteristics include progressive and centripetal enhancement, spoke-wheel pattern, nodular enhancement, and delayed enhancement of central fibrous scar. Hypointensity on T2- and diffusion-weighted images are due to hemosiderin deposition and fibrous tissue.

Sclerosing angiomatoid nodular transformation presenting with thrombocytopenia after laparoscopic splenectomy - Case report and systematic review of 230 patients

Background

Sclerosing angiomatoid vascular transformation (SANT) is a rare vascular disease of the spleen, which is difficult to diagnose due to its pre-intervention appearance of malignancy. Case Report: An 85-year-old male was transferred to our clinic for thrombocytopenia and splenic mass. A contrast enhanced abdominal CT and MRI showed nodular lesions, the largest 50mm in diameter, and several areas of heterogeneous contrast field involvement in the spleen parenchyma. Laparoscopic splenectomy was performed with normal range of platelet level. The patient's postoperative course was uneventful and he was discharged on the 6th postoperative day. Histopathology revealed SANT. The patient is now in the 18 th month of remission with platelet levels within normal range and with no recurrence.

Results

Between 2004 and April 2020, a total of 230 SANT patients who underwent laparoscopic or open splenectomy or biopsy were reported in the literature. Most patients were female (52.1%), and the median age was 46 years (9 weeks-85 years). Most patients were asymptomatic (56%). Open splenectomy was performed on 166 patients (72.1%),laparoscopic splenectomy on 35 patients (15.2%) and laparoscopic partial splenectomy on 15 patients (6.5%). The median operation time and spleen weight were 143 minutes (88-213) and 260gr (68-2,720), respectively. Median follow-up time was 12 months (0-166). No recurrence was seen in patients undergoing total splenectomy.

Conclusion

SANT is an unusual disease of the spleen. In the light of this systematic review, a minimally invasive method for total or partial splenectomy,specifically laparoscopy, can be preferred as the treatment of choice.

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SANT is a rare, benign vascular disease of the spleen.

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The correct diagnosis of SANT pre-intervention or preoperatively is a significant for treatment.

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Laparoscopic splenectomy is curative treatment for SANT.

Sclerosing angiomatoid nodular transformation of the spleen: unusual case presentation in an intravenous drug user

An unusual presentation of sclerosing angiomatoid nodular transformation in a 42-year-old man who was admitted with jaundice, deranged liver function tests and subsequently diagnosed with acute hepatitis C infection in the context of recent intravenous drug use. During his admission, he had an ultrasound of the abdomen followed by a CT thorax, abdomen and pelvis which showed splenomegaly and a large splenic lower pole mass that was hypoechoic and concerning for lymphoma. A bone marrow biopsy showed no evidence of lymphoma and an ultrasound-guided biopsy of the splenic mass suggested unusual features with vascular proliferation, either neoplastic or reactive, with no evidence of lymphoma or high-grade sarcoma. Given the concern for malignancy, an open splenectomy was required to determine the nature of the lesion with histologic findings consistent with a non-neoplastic benign vascular lesion favouring sclerosing angiomatoid nodular transformation.

Laparoscopic Splenectomy in a Patient with Sclerosing Angiomatoid Nodular Transformation

Sclerosing angiomatoid nodular transformation (SANT) of the spleen is a specific, tumor-forming, non-neoplastic, vascular lesion with few reported cases worldwide. Herein, we describe the case of a patient who underwent laparoscopic splenectomy for SANT. A 47-year-old woman underwent upper gastrointestinal endoscopy for suspected gastric submucosal tumor. Contrast-enhanced abdominal computed tomography revealed the presence of a gradually enhancing lesion in the splenic hilum. Although we suspected splenic fibrotic hamartoma, malignancy could not be ruled out. Therefore, the patient underwent laparoscopic splenectomy, resulting in the histopathological diagnosis of SANT. Although SANT is a benign tumor, it may be difficult to obtain definitive diagnosis using preoperative imaging alone. Because the long-term natural history of SANT is unknown, we believe that splenectomy could be an appropriate technique for the diagnosis and treatment of SANT.

Imaging Features of Sclerosing Angiomatoid Nodular Transformation in Spleen

The purpose of this study was to evaluate the features of sclerosing angiomatoid nodular transformation (SANT) in spleen on the imaging of computed tomography (CT) and magnetic resonance (MR).

Sclerosing angiomatoid nodular transformation of the spleen

The authors described a case of sclerosing angiomatoid nodular transformation of the spleen (SANT) in a 50-year-old woman presented with persistent neutrophilia and unintentional weight loss. An incidental splenic mass was initially found on abdominal ultrasound. It was found to be progressive in size and with high likelihood of central necrosis on further CT of abdomen and pelvis. The patient subsequently underwent an uneventful laparoscopic splenectomy. The splenic specimens were sent for laboratory analysis and the histopathological findings were highly suggestive of SANT. The patient then had routine surgical follow-ups and was eventually discharged with no further clinical concern.

Sclerosing angiomatoid nodular transformation of the spleen: case report of a metastatic carcinoma-simulating disorder

Sclerosing angiomatoid nodular transformation (SANT) is a rare nonneoplastic splenic disorder of unknown etiopathogenesis. This condition is usually found incidentally on imaging studies. Because of its similar features, SANT can wrongly be described as metastatic carcinoma. A 61-year-old Caucasian male was referred to our general surgery outpatient clinic regarding unusual splenic nodular formations in a routine abdominal ultrasound. All diagnostic exams performed confirmed metastatic splenic lesions, but no primary tumor was found. A laparoscopic splenectomy was performed for diagnostic purposes. Histopathology revealed SANT. Benign tumors of the spleen are uncommon entities and can easily be mistaken by malignant secondary lesions. The differential diagnosis of SANT should include other vascular lesions as well as metastatic carcinoma and inflammatory pseudotumor. It is widely recommended that a splenectomy should be performed because only by histopathology and immunohistochemistry staining, the definitive diagnosis of SANT can be made.

Sclerosing angiomatoid nodular transformation of the spleen (SANT) in a patient with clear cell carcinoma of the uterus: a case report

Background

Sclerosing angiomatoid nodular transformation of the spleen is a very rare benign vascular lesion recently described. Usually, sclerosing angiomatoid nodular transformation of the spleen is an incidental finding; the association with malignant tumors is extremely rare. To the best of our knowledge, we report the first case of sclerosing angiomatoid nodular transformation of the spleen associated with uterine clear cell carcinoma.

Case presentation

A 49-year-old Arabic woman presented to our institute with abdominal pain and distention. An abdominal computed tomographic scan was obtained, which showed a 14-cm uterine malignant tumor and a 4-cm isolated splenic nodule suggesting a metastatic lesion. The tumor was limited to the uterus but did not extend beyond. The patient underwent surgical treatment, and the histopathological examination of the resected uterine and splenic specimens disclosed invasive uterine clear cell carcinoma and sclerosing angiomatoid nodular transformation of the spleen, respectively. The patient had no signs of the disease 17 months after surgical treatment.

Conclusions

Sclerosing angiomatoid nodular transformation of the spleen is a very rare benign disease with a misleading presentation when associated with a malignant tumor. Pathological assessment of the resected spleen is the only way to achieve the correct diagnosis.

Sclerosing angiomatoid nodular transformation of the spleen: A case report of thrombocytopenia and a hypervascular splenic mass

Introduction

Sclerosing Angiomatoid Nodular Transformation of the spleen is a benign vascular lesion with no known etiology.

Presentation of Case

We report a new case in a symptomatic twenty-one-year old female with thrombocytopenia and a hypervascular splenic mass discovered on ultrasound. Two MRIs were performed prior to hand-assisted laparoscopic splenectomy. The specimen was sent for histopathologic analysis with confirmation of final diagnosis from an outside facility.

Discussion

Sclerosing Angiomatoid Nodular Transformation of the spleen is most often discovered incidentally as a solitary splenic mass. The presence of a spoke-wheel pattern should alert the radiologist to this as a possibility.

Conclusion

Ultrasound and MR imaging findings can be used to accurately diagnose cases of splenic Sclerosing Angiomatoid Nodular Transformation. Susceptibility artifact within the lesion may be directly related to the amount of iron deposition.

Splenomegaly: A Combined Clinical and Radiologic Approach to the Differential Diagnosis

An enlarged spleen (splenomegaly) is a common imaging finding and may be related to a broad array of underlying conditions. The multifaceted functions of the spleen make it susceptible to involvement by a variety of pathophysiologic processes. Understanding these conditions and incorporating all relevant clinical and radiologic data allow narrowing the differential diagnosis.

Sclerosing angiomatoid nodular transformation of the accessory spleen: A case report and review of literature

RATIONALE

Sclerosing angiomatoid nodular transformation (SANT) is a rare case which usually occurs in spleen, but our case occurs in accessory spleen.

PATIENT CONCERNS

We reported a case of a 27 year old man who was identified with an isodense mass in the left abdominal cavity by ultrasonicphysical examination without symptoms. Blood routine and tumor markers (alpha fetal protein, carcinoembryonic antigen, CA19-9, CA125) were normal.

DIAGNOSES

The tumor was firstly diagnosed as left abdominal mass and its origin was considered as small intestinal by the radiologist. The pathological diagnosis was the sclerosing angiomatoid nodular transformation (SANT) of the accessory spleen.

INTERVENTIONS

Laparoscopic splenectomy is a more reliable method for the treatment of SANT.

OUTCOMES

Non-enhanced CT showed iso-intensity lesion of the accessory spleen, and enhanced CT showed progressive enhancement. According to the above characteristics, we should consider the diagnosis of spleen SANT. We reviewed some literatures to summarize the characteristics of SANT.

The Incidental Splenic Mass at CT: Does It Need Further Work-up? An Observational Study

Purpose To evaluate whether an incidentally noted splenic mass at abdominal computed tomography (CT) requires further imaging work-up. Materials and Methods In this institutional review board-approved HIPAA-compliant retrospective study, a search of a CT database was performed for patients with splenic masses at CT examinations of the abdomen and chest from 2002 to 2008. Patients were divided into three groups: group 1, patients with a history of malignancy; group 2, patients with symptoms such as weight loss, fever, or pain related to the left upper quadrant and epigastrium; and group 3, patients with incidental findings. Patients' CT scans, follow-up examinations, and electronic medical records were reviewed. Final diagnoses of the causes of the masses were confirmed with imaging follow-up (83.9%), clinical follow-up (13.7%), and pathologic examination (2.4%). Results This study included 379 patients, 214 (56.5%) women and 165 (43.5%) men, with a mean age ± standard deviation of 59.3 years ± 15.3 (range, 21-97 years). There were 145 (38.3%) patients in the malignancy group, 29 (7.6%) patients in the symptomatic group, and 205 (54.1%) patients in the incidental group. The incidence of malignant splenic masses was 49 of 145 (33.8%) in the malignancy group, eight of 29 (27.6%) in the symptomatic group, and two of 205 (1.0%) in the incidental group (P < .0001). The incidental group consisted of new diagnoses of lymphoma in one (50%) patient and metastases from ovarian carcinoma in one (50%) patient. Malignant splenic masses in the incidental group were not indeterminate, because synchronous tumors in other organs were diagnostic of malignancy. Conclusion In an incidental splenic mass, the likelihood of malignancy is very low (1.0%). Therefore, follow-up of incidental splenic masses may not be indicated. ^© RSNA, 2018.

A case of sclerosing angiomatoid nodular transformation of the spleen with increased accumulation of fluorodeoxyglucose after 5-year follow-up

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Although sclerosing angiomatoid nodular transformation (SANT) of the spleen is a new entity defined as a benign pathologic lesion, it is very difficult for ruling out the malignancy in preoperative imaging studies.

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Even when accumulation of fluorodeoxyglucose increased slightly during the follow-up period and suggested the possibility of malignant diseases, it is necessary to make a diagnosis of splenic SANT comprehensively.

Introduction

Sclerosing angiomatoid nodular transformation (SANT) of spleen is a new entity defined as a benign pathologic lesion. Fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) shows weak accumulation, thereby ruling out the malignancy in preoperative diagnosis is difficult. Herein, we reported a case of shrinking SANT with increased FDG accumulation during a 5-year follow-up period, which was treated by laparoscopic splenectomy.

Presentation of case

A 64-year-old female had been referred to our hospital for the evaluation of a splenic tumor. Initial contrast-enhanced computed tomography (CT) showed a well-defined, and ovoid hypoattenuating lesion, measuring 52 mm in diameter in the spleen. Initial PET/CT revealed accumulation of FDG in the tumor (maximum standardized uptake value [SUVmax]: 2.8). The mass was diagnosed as SANT, and the patient was followed-up every 6–12 months for 5 years. Follow-up PET/CT revealed increased accumulation of FDG (SUVmax: 3.5). As it was suspicious considering the differential diagnosis, including malignant lymphoma and inflammatory pseudotumor, she underwent laparoscopic splenectomy. The pathological results showed three types of vessels including capillaries, ectatic small veins, and sinusoids-like vessels, consistent with the features of SANT.

Discussion

A SANT may have features that resemble those of malignancy, including the growing mass and the increase of FDG accumulation.

Conclusion

Although the preoperative diagnosis of SANT is difficult, it is necessary to make a diagnosis of SANT comprehensively, even when accumulation of FDG increased slightly during the follow-up period and suggested the possibility of malignant diseases.

Sclerosing Angiomatoid Nodular Transformation of the Spleen: An uncommon Cause of Abdominal Pain

Sclerosing angiomatoid nodular transformation (SANT) is a rare and benign lesion arising from the red pulp of the spleen, with an unknown etiopathogenesis. These tumors are usually asymptomatic or cause nonspecific abdominal pain. Most SANTs are found incidentally on radiographic examination, or during surgery for an unrelated condition. Therefore, high clinical suspicion is of great importance for the diagnosis. Splenectomy provides complete cure, and no recurrence and/or malignant transformation was reported to date. In this study, a rare case of SANT was reported in a young adult male, and was discussed with the relevant literature.

How to cite this article: Atas H, Bulus H, Akkurt G. Sclerosing Angiomatoid Nodular Transformation of the Spleen: An uncommon Cause of Abdominal Pain. Euroasian J Hepato-Gastroenterol 2017;7(1):89-91.

Sclerosing Angiomatoid Nodular Transformation of the spleen, focal nodular hyperplasia and hemangioma of the liver: A tale of three lesions

Sclerosing Angiomatoid Nodular Transformation (SANT) of the spleen is a benign vascular lesion with peculiar histological features. The pathogenesis of SANT is still largely unknown and variable etiologies have been proposed, including autoimmune, inflammatory, and/or vascular disorders. The present report describes a unique case of splenic SANT, associated with focal nodular hyperplasia and a sclerosing hemangioma of the liver. The clinic-pathological features of such an unusual case are thoroughly illustrated. Its possible pathogenic mechanisms are also briefly addressed.

Sclerosing angiomatoid nodular transformation of the spleen: A case report and literature review

Sclerosing angiomatoid nodular transformation (SANT) is a rare benign splenic vascular lesion. Since it was first defined in 2004, a total of 132 cases of SANT have been reported in ~50 studies in the English literature. However, it remains difficult to form a definitive pre-operative differential diagnosis of SANT compared with other splenic tumors or malignant lesions. The present study reports a pathologically proven case of SANT in a 29-year-old man who initially presented with left upper quadrant and back discomfort. The study also provides a review of the current knowledge on the condition, including the clinical profile, imaging features, cytological features, differential diagnosis and treatment of SANT. The most important distinguishing features of SANT are its typical vascular character and lack of other features that are typical of a granuloma. A splenectomy is required and the diagnosis is based on pathological analysis.

The value of contrast-enhanced dynamic and diffusion-weighted MR imaging for distinguishing benign and malignant splenic masses

OBJECTIVE

To assess the value of contrast-enhanced dynamic and diffusion-weighted (DW) MR imaging for differentiating malignant from benign splenic lesions.

METHODS

This retrospective study included 51 patients with 35 benign and 16 malignant focal splenic lesions. All patients underwent contrast-enhanced dynamic and DW MR imaging. Two radiologists evaluated the MR images in consensus. Significant imaging findings on univariate and multivariate analyses were identified and their diagnostic performance for predicting the malignant splenic lesion was analyzed. Using receiver-operating characteristic analysis, the optimal cut-off of the apparent diffusion coefficient (ADC) value corresponding to the maximal Youden's index (J) for differentiating the two groups was determined.

RESULTS

In univariate analysis, low signal intensity (SI) on the arterial, portal and 3-min delayed-phase images, high or iso SI on the DW image, iso or low SI on the ADC map, the presence of diffusion restriction and arterial hypovascularity with a progressive enhancement pattern were more frequently observed (p < 0.05) in malignant splenic lesions. The ADC value was significantly lower for malignancy than for benignancy (0.78 ± 0.24 vs 1.16 ± 0.53 × 10(-3) mm(2) s(-1); p < 0.001). The optimal cut-off ADC value for differentiating the two groups was 0.995 × 10(-3) mm(2) s(-1). In multivariate analysis, findings that differentiated malignant from benign splenic lesions were low SI on the 3-min delayed-phase image [odds ratio (OR), 27.68; p = 0.006] and the presence of diffusion restriction (OR, 48.01; p = 0.002). When two of these criteria were combined, 12 (75.0%) of 16 malignant splenic masses were identified with a specificity of 100%.

CONCLUSION

Contrast-enhanced dynamic and DW MR imaging may be helpful for differentiating malignant from benign splenic lesions. A low SI on the 3-min delayed phase and diffusion restriction are the most reliable findings for the differentiation of malignant from benign splenic lesions.

ADVANCES IN KNOWLEDGE

Dynamic and DW MR imaging help in distinguishing malignant from benign splenic lesions. A low SI on the 3-min delayed phase and diffusion restriction are the most reliable findings for the differentiation of malignant from benign splenic lesions.

Sclerosing angiomatoid nodular transformation of the spleen

Sclerosing angiomatoid nodular transformation (SANT) of spleen is a very rare benign entity with unknown etiology. Here, we report this unusual case in a fit middle-aged gentleman and discuss various diagnostic modalities along with the management of this condition.

Two cases of sclerosing angiomatoid nodular transformation of the spleen with gradual growth: usefulness of diffusion-weighted imaging

Sclerosing angiomatoid nodular transformation (SANT) is a recently recognized and rare, nonneoplastic lesion of the spleen. Some papers have reported an increased SANT diameter during the follow-up period. We present two cases of SANT whose size increased during the follow-up period. Diffusion-weighted magnetic resonance imaging (DWI) findings correlated well with the pathological findings of SANT, the multinodular high-intensity area as the angiomatoid nodules and the peripheral low-intensity area as fibrous tissues. Therefore, DWI may be a useful imaging tool.

Hand-assisted laparoscopic splenectomy for sclerosing angiomatoid nodular transformation of the spleen complicated by chronic disseminated intravascular coagulation: a case report

A 36-year-old man who presented with a nosebleed and anemia was referred to our hospital. Laboratory test results showed platelet depletion, decreased levels of fibrinogen, and increased fibrinogen degeneration products. CT showed a 13-cm splenic tumor. T2 -weighted MRI revealed a high-intensity mass. We preoperatively diagnosed splenic hemangioma with chronic disseminated intravascular coagulation and scheduled an operation to relieve the disseminated intravascular coagulation. We also performed hand-assisted laparoscopic splenectomy to ensure easy handling of the splenomegaly. The resected specimen microscopically consisted of hemorrhages and hemangiomatous lesions, and multiple angiomatoid nodules were scattered and separated by fibrocollagenous stroma with inflammatory cells. Three types of vessels (capillaries, sinusoids and small veins) were contained in the angiomatoid nodules, and the pathological diagnosis was sclerosing angiomatoid nodular transformation. The results of this case suggest that we should consider sclerosing angiomatoid nodular transformation in the differential diagnosis of patients with splenic tumors, as sclerosing angiomatoid nodular transformation with hemangiomatous features may cause coagulation disorders for which splenectomy should be performed.