Sclerosing angiomatoid nodular transformation of the spleen: case report

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 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, a rare cause for splenectomy: Two case reports

BACKGROUND

Sclerosing angiomatoid nodular transformation (SANT) is a rare benign disease of the spleen with unknown origin. Clinical symptoms are inhomogeneous, and suspicious splenic lesion often found incidentally, leading to splenectomy, as malignancy cannot securely be ruled out. Diagnosis is made histologically after resection.

CASE SUMMARY

Two cases of German, white, non-smoking, and non-drinking patients of normal weight are presented. The first one is a 26-year-old man without medical history who was exhibiting an undesired weight loss of 10 kg and recurring vomiting for about 18 mo. The second one is a 65-year-old woman with hypertension who had previously undergone gynecological surgery, suffering from a lasting feeling of abdominal fullness. Both showed radiologically an inhomogeneous splenic lesion leading to splenectomy approximately 6 and 9 wk after surgical presentation. Both diagnoses of SANT were made histologically. Follow-up went well, and both were treated according to the recommendation for asplenic patients.

CONCLUSION

SANT is a rare cause of splenectomy and an incidental histological finding. Further research should focus on clinical and radiological diagnosis of SANT as well as on treatment of patients with asymptomatic and small findings.

Sclerosing angiomatoid nodular transformation (SANT) of spleen mimicking a splenic abscess: Case report and review of the literature

INTRODUCTION

SANT of the spleen is a benign lesion that does not recur after splenectomy with unknown etiology.

PRESENTATION OF THE CASE

We report a case of sclerosing angiomatoid nodular transformation (SANT) of the spleen mimicking a splenic abscess in a patient with imaging studies that failed to differentiate this lesion from other splenic lesions.

DISCUSSION

SANT of the spleen is a rare condition, with only less than 100 cases reported in the literature. Clinically, SANT is only a kind of described pathological diagnostic conception. As in our case, these splenic lesions are often incidental findings on imaging studies performed for other reasons.

CONCLUSION

The patient was treated with splenectomy, which has proved to be both diagnostic and therapeutic. Although histology can lead to the diagnosis of vascular tumor, immunohistochemistry is the only way to confirm the diagnosis.

Multimodality imaging of splenic sclerosing angiomatoid nodular transformation

Sclerosing angiomatoid nodular transformation (SANT) is an exceedingly rare, benign and proliferative vascular lesion that arises from the splenic red pulp. It is often an incidental finding on imaging. The diagnosis of SANT is confirmed via histopathological examination of the resected spleen. Herein, we present a case of SANT and describe its typical imaging characteristics. An asymptomatic 39-year-old man was found to have a 3.1 cm × 2.7 cm × 2.3 cm hypoechoic splenic lesion during abdominal ultrasonography, which was performed to investigate his elevated gamma-glutamyl transpeptidase and alanine transaminase levels. Contrast-enhanced computed tomography suggested a vascular splenic lesion, while magnetic resonance imaging demonstrated features consistent with SANT. In view of the increasing size of the lesion on follow-up imaging, the patient elected for splenectomy. Histopathological examination confirmed SANT, and the lesion was completely resected by laparoscopic splenectomy.

Sclerosing angiomatoid nodular transformation of the spleen: CT and MRI features with pathologic correlation

OBJECTIVE

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

MATERIALS AND METHODS

Nine patients with surgically resected and pathologically confirmed sclerosing angiomatoid nodular transformation were included in the study. Clinical history was reviewed to determine patient demographics and symptoms at presentation. Gross pathologic, histologic, and immunohistochemical findings were recorded. CT (n = 9) and MRI (n = 4) examinations were evaluated for lesion shape and margins, intrinsic characteristics, and enhancement pattern.

RESULTS

Patients included were six women and three men, with a mean age of 41.2 years. Pathologic features of sclerosing angiomatoid nodular transformation included multiple angiomatous nodules in a radiating pattern with a central stellate fibrous scar and evidence of hemosiderin deposition. On imaging, the lesions were solitary and round, 78% having a lobulated margin. They were heterogeneously hypoenhancing during the arterial and portal venous phases of contrast-enhanced CT or MRI, with peripheral enhancing radiating lines in 88% of lesions. They showed progressive enhancement and were isoenhancing or hyperenhancing in the delayed phase. A hypoenhancing central scar was shown on imaging in 22% of lesions. All lesions were hypointense on T2-weighted images.

CONCLUSION

Sclerosing angiomatoid nodular transformation shows characteristic CT and MRI findings reflecting the underlying pathology. Typical features are a solitary, round, lobulated mass with early peripheral enhancing radiating lines and progressive enhancement of the angiomatous nodules; delayed enhancement of the fibrous tissue; and hypo-intense T2 signal intensity from hemosiderin deposition.

Sclerosing angiomatoid nodular transformation of the spleen related to IgG4-associated disease: report of a case

Sclerosing angiomatoid nodular transformation (SANT) of the spleen is a rare benign vascular mass, with fewer than 100 cases documented. It is generally recognized as a vascular lesion that develops in the red pulp of the spleen; however, its pathogenesis is not clearly defined. We report a case of SANT of the spleen, which presents evidence to support the hypothesis that this disease entity is associated with IgG4-associated disease. Microscopically, the tumor was composed of multiple vascular structures separated by fibrous connective tissue and immunohistochemical examination revealed positive staining for CD31, CD34, factor VIII, and IgG4. Further research based on large number of cases is warranted to clarify the pathogenesis of this tumor.

Sclerosing Angiomatoid Nodular Transformation (SANT) of the spleen: Case report and review of the literature

INTRODUCTION

Sclerosing Angiomatoid Nodular Transformation of the spleen (SANT) is a rare benign vascular lesion of the spleen with extensive sclerosis and unknown etiology.

PRESENTATION OF CASE

We report a new case of SANT of the spleen found in a 53-year-old female following detection of a splenic mass on a routine computed tomography (CT). The patient underwent an uncomplicated laparoscopic splenectomy and the specimen was sent for histopathologic examination.

DISCUSSION

A review of the 97 reported cases of SANT found in the literature was undertaken. There were 43 males and 54 females with a median age of 46 years (range: 11-82 years). SANT is classically considered to be a female predominant disease, however 44.3% of reported case were male and the gender predilection may soon be neutralized as more cases are reported. 65 of the 97 (67%) patients were in 30-60 year age group. The majority of lesions (n=50) were incidentally found on imaging, and for those patients presenting with symptoms, abdominal pain (n=18) was the predominant symptom.

CONCLUSION

The diagnosis of SANT should be considered in any patient presenting with a splenic lesion that contains an angiomatoid or inflammatory component. As the differential diagnosis for SANT includes malignant pathologies, and currently no reliable diagnostic radiological feature has been identified to differentiate between these conditions, SANT will continue to be diagnosed on the basis of surgical histopathology.

Sclerosing angiomatoid nodular transformation of the spleen treated by laparoscopic partial splenectomy

The authors describe a case of sclerosing angiomatoid nodular transformation (SANT) of the spleen treated at the 2^nd Department of Surgery, Jagiellonian University, Medical College. The patient was a 23-year-old woman. Clinically she presented with 2-year history of recurrent mild fever, diffuse joint pain, abdominal discomfort and iron deficiency anaemia of chronic disease. The laboratory tests revealed a non-characteristic chronic inflammatory response. A splenic solid lesion 9 cm in diameter was found on abdominal computed tomography. The patient underwent uneventful laparoscopic resection of the upper half of the splenic parenchyma. The resected tumour showed characteristic histological and immunophenotypical findings of SANT as previously described in the literature. In long-term follow-up, improvement of preoperative symptoms and abnormalities in the blood tests was documented.

Sclerosing angiomatoid nodular transformation of the spleen: CT, MR, PET, and ⁹⁹(m)Tc-sulfur colloid SPECT CT findings with gross and histopathological correlation

Sclerosing angiomatoid nodular transformation (SANT) is a benign, proliferative vascular lesion affecting the spleen. Few reports detailing the cross sectional and PET appearance of this lesion are available, and the lesion’s behavior with ^99mTc-sulfur colloid scintigraphy is previously unreported. Sclerosing nodular transformation of the spleen shows increased tracer accumulation on positron emission tomography, and a central scar-like appearance with an enhancing capsule and radiating septae on CT and MR studies that reflects the gross and histopathological features of the lesion may be visible. An understanding of this pathological finding may allow prospective recognition of the sclerosing nodular transformation of the spleen on cross sectional imaging studies.

Clonal X-chromosome inactivation suggests that splenic cord capillary hemangioma is a true neoplasm and not a subtype of splenic hamartoma

Splenic hamartoma is a rare tumor-like lesion composed of structurally disorganized red pulp elements. It has been hypothesized that two other splenic lesions, cord capillary hemangioma and myoid angioendothelioma, may fall within the spectrum of splenic hamartoma, simply representing morphological variants. In this study, we compared the vascular and stromal composition of cord capillary hemangioma and myoid angioendothelioma with those of classical hamartoma. In addition, we assessed the clonal vs polyclonal nature of the lesions in nine female cases by performing clonality analysis for X-chromosome inactivation at the human androgen receptor locus (HUMARA) on laser-assisted microdissected samples. In 15 of 17 cases, increased reticulin and/or collagen content was observed. The classical hamartoma cases showed a vasculature predominantly composed of CD8+ CD31+ CD34- splenic sinuses, whereas cases of cord capillary hemangioma and myoid angioendothelioma contained many CD8- CD31+ CD34+ cord capillaries, but very little CD8+ vasculature. All cases lacked expression of D2-40 and Epstein Barr virus-encoded RNA. All cases showed a proliferation index of ≤5% by Ki-67. Cases of classical hamartoma lacked significant perisinusoidal expression of collagen IV and low-affinity nerve growth factor receptor. Both markers were variably expressed in the other lesions. Increased CD163-positive histiocytes were found in four cases (three cord capillary hemangiomas and one myoid angioendothelioma). HUMARA analysis was informative in all nine tested cases, of which three cases showed a non-random X-chromosome inactivation pattern, indicating clonality. All three clonal cases were cord capillary hemangiomas. Our study has shown that in spite of considerable morphologic heterogeneity and overlapping features, classical hamartoma and cord capillary hemangioma and myoid angioendothelioma are different in terms of their vascular and stromal composition. Clonality analysis supports a true neoplastic origin for the cord capillary hemangioma. A larger study using additional immunohistochemical and molecular studies is necessary to further evaluate the biological significance of the current findings.

Sclerosing angiomatoid nodular transformation of the spleen masquerading as a sarcoma metastasis

We report a case of sclerosing angiomatoid nodular transformation (SANT) of the spleen presenting as an incidental splenic mass in a patient with a history of retroperitoneal spindle cell sarcoma. Imaging studies and preoperative fine needle biopsy failed to differentiate this lesion from other vascular splenic lesions or a metastatic focus of a prior sarcoma. The patient was treated with splenectomy, which has proved both diagnostic and therapeutic in this and other cases of SANT. Although histology can lead to the diagnosis of vascular tumor, immunohistochemistry is the only way to confirm the diagnosis of SANT. The etiology of SANT is unknown. SANT of the spleen is a benign lesion that does not recur after splenectomy.

Sclerosing angiomatoid nodular transformation of the spleen masquerading as a sarcoma metastasis

We report a case of sclerosing angiomatoid nodular transformation (SANT) of the spleen presenting as an incidental splenic mass in a patient with a history of retroperitoneal spindle cell sarcoma. Imaging studies and preoperative fine needle biopsy failed to differentiate this lesion from other vascular splenic lesions or a metastatic focus of a prior sarcoma. The patient was treated with splenectomy, which has proved both diagnostic and therapeutic in this and other cases of SANT. Although histology can lead to the diagnosis of vascular tumor, immunohistochemistry is the only way to confirm the diagnosis of SANT. The etiology of SANT is unknown. SANT of the spleen is a benign lesion that does not recur after splenectomy.

Sclerosing Angiomatoid Nodular Transformation (SANT) of the Spleen: A Report of 3 Cases

The authors describe 3 cases of sclerosing angiomatoid nodular transformation (SANT) of the spleen diagnosed at Memorial Sloan-Kettering Cancer Center within a 1-year period (July 2008 to June 2009). All patients were female, older than 50, with lesions ranging in size from 2 to 4 cm. All were alive and well after splenectomy. All the cases showed characteristic histological and immunophenotypical findings as previously described in the literature, including scattered IgG4positive plasma cells in the fibrosclerotic stroma. Of the 3 patients, 2 had a history of carcinoma, and metastasis was of concern, but a PET scan in one of these patients showed minimal to absent FDG activity suggesting that this process was of a benign indolent nature. However, in 1 patient, a PET scan revealed positive FDG activity, heightening clinical concern for malignancy.