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

Controversies in the Spleen: Histiocytic, Dendritic, and Stromal Cell Lesions

Histiocytic, dendritic, and stromal cell lesions that occur in the spleen are challenging diagnostically, not well studied due to their rarity, and therefore somewhat controversial. New techniques for obtaining tissue samples also create challenges as splenectomy is no longer common and needle biopsy does not afford the same opportunity for examination of tissue. Characteristic primary splenic histiocytic, dendritic, and stromal cell lesions are presented in this paper with new molecular genetic findings in some entities that help differentiate these lesions from those occurring in non-splenic sites, such as soft tissue, and identify possible molecular markers for diagnosis.

Conventional and contrast-enhanced ultrasound of scleroring angiomatoid nodular transformation of the spleen

Sclerosing angiomatoid nodular transformation (SANT) is an uncommon non-tumorous disease of the spleen. The low morbidity and non-specific clinical symptoms of SANT might cause a misdiagnosis. The present study reported a case of a 31-year-old female with a SANT of the spleen. Findings on clinical manifestations and examinations, especially on contrast-enhanced ultrasound (CEUS), were carefully analyzed, and relevant literatures have also been reviewed.

Sclerosing angiomatoid nodular transformation (SANT) of the spleen: a rare cause of acute abdomen

Sclerosing angiomatoid nodular transformation (SANT) of the spleen is an extremely rare benign lesion. It originates from the spleen's red pulp; however, its pathogenesis is not clearly defined. These tumors are usually asymptomatic or cause nonspecific abdominal symptoms. Most SANTs are found incidentally on radiographic examination or during surgery for an unrelated condition. The differential diagnosis from other splenic tumors or malignant lesions can be challenging due to the risk for a possible malignancy of the suspicious lesion. As more SANTs are being discovered and treated, they should always be considered in the differential.

We present the case of an otherwise healthy 30-year-old female; she presented with abdominal pain and a mass in her spleen. Surgery was performed, and an SANT was discovered. The patient underwent full recovery, and on follow-up is doing well.

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 presenting with abdominal hemorrhage: First report in infancy

A limited number of sclerosing Angiomatoid Nodular Transformation (SANT) have been reported in pediatric age. We describe the first case of SANT occurring in a nine-week-old female infant that was admitted to our unit for severe abdominal distension and rectal bleeding. Enlarged spleen was detected on physical examination. Laboratory investigations revealed severe anemia and coagulation abnormalities. Abdominal ultrasound and computed tomography revealed ascites and splenomegaly with a large mass at the lower medial splenic pole. A diagnosis of intraabdominal hemorrhage was presumed and an exploratory laparotomy was performed. A complete transformation of the giant splenomegaly to bossellated masses and multiple bleeding capsular ruptures without subcapsular hematoma were found and an urgent splenectomy was performed. At histology, a SANT was diagnosed (CD34, CD31, CD8 positivity). The postoperative follow up was uneventful. SANT may also occur in infancy with a potentially lifethreatening presentation. Splenectomy may represent the only treatment in severe cases.

Sclerosing angiomatoid nodular transformation in the spleen: A case series study and literature review

To assess the clinicopathologic features, differential diagnosis, and pathogenesis of sclerosing angiomatoid nodular transformation (SANT) of the spleen.The clinical characteristics of 7 cases with SANT were retrospectively analyzed. Histochemical and immunohistochemical (EnVision method) examinations were performed. Moreover, quantitative assessment of IgG4 and IgG-positive cells was performed.The 7 SANT patients included 1 female and 6 males, with ages ranging from 7 to 60 years (mean 33.4 years). They showed no specific clinical manifestations. Macroscopically, the surface of the excised masses was gray-white, and vague nodularity was observed. Mass sizes ranged from 3.0 to 7.0 cm (mean 5.5 cm). Microscopically, all cases were characterized based on multiple angiomatoid nodules of various sizes embedded in a fibrosclerotic stroma. The nodules were round and sometimes convoluted. Moreover, the nodules were composed of slit-like, irregularly-shaped, or slightly dilated vascular spaces lined by plump endothelial cells, and interspersed with a population of spindly or ovoid cells. Immunohistochemical examination showed a heterogeneous staining pattern, with the lining cells of small capillaries expressing CD34 and those of sinusoid-like structures expressing CD8. CD31 was stained in the lining and interspersed cells, thus resulting in a complex meshwork. Additionally, the lining cells were focally positive for CD68. Vimentin and smooth muscle antibody were expressed in all 7 cases, whereas no desmin or CD21 was detected. IgG4-positive cells accounted for 2 to 5 per high-power field (mean 3.7). Furthermore, the IgG-positive cells accounted for 2 to 8 per high-power field (mean 4.2).SANT is a rare primary benign tumor-like lesion of the spleen, and has characteristic histopathological features and immunohistochemical profiles. SANT should be distinguished from other angiomatoid tumors and tumor-like lesions. Moreover, SANT could be treated by splenectomy, with favorable prognosis. The relationship between SANT and IgG4-related sclerosing lesions remains to be clarified.

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.

Infrequent organ involvement of IgG4-related diseases: a literature review

IgG4-related disease (IgG4-RD) is a chronic and systemic disease that can involve multiple organs. The most commonly involved organs include the salivary glands, orbital adnexal structures, paranasal sinus, thyroid, lungs, breasts, aorta, pancreas, biliary ducts, kidneys, retroperitoneum, lymph nodes, prostate, pituitary, and endocranium. Due to increased disease research, several new site-specific nuances of IgG4-RD have been described. The authors have reviewed the recent literature and briefly summarize the infrequent organ involvement of IgG4-RD.

Sclerosing angiomatoid nodular transformation of the spleen presenting rapid growth after adrenalectomy: Report of a case

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SANT displayed a rapid growth in size from 20 mm to 70 mm during 3 years after adrenalectomy.

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Splenectomy was performed by hand assisted laparoscopic surgery (HALS).

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Corticosteroids might be useful for treating SANT.

Introduction

Sclerosing angiomatoid nodular transformation (SANT) is a rare benign lesion with an unknown natural history and pathogenesis. So far fewer than 100 cases were documented, but detailed incidence and prevalence are unknown.

Presentation of case

We report a case of SANT of the spleen in a 37-year-old man that showed rapid growth after adrenalectomy for primary aldosteronism. Computed tomography showed a nodule in the spleen that increased in size from 2.0 cm to 7.0 cm during 3 years of observation.

Discussion

This case is reported because data regarding growth rates and natural history of these lesions are limited and few cases have been reported to show the rapid growth progression seen in this case.

Conclusion

Decreases in glucocorticoid concentrations following adrenalectomy may have contributed to the rapid growth of SANT of the spleen, because SANT is considered to be related to immunoglobulin G4-associated disease.

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.

Multifocal sclerosing angiomatoid nodular transformation of the spleen: a case report and review of literature

Sclerosing angiomatoid nodular transformation (SANT) is a relatively new entity in the spleen, which usually presents in the form of single nodule. Only 5 multifocal SANT cases have been reported in English literature. The present case is the first report of a 38-years-old male patient with SANT in the form of multiple nodules, who has been cured via laparoscope. In comparison to solitary SANT, multifocal SANT occurs more likely in males than females and association with malignant neoplasm has not been described yet. Multifocal SANT as well as solitary SANT show some relationships with IgG4-related sclerosing disease.

The changing faces of IgG4-related disease: Clinical manifestations and pathogenesis

Since the earliest reports in 2001, immunoglobulin G4 (IgG4)-related disease has been defined as an autoimmune systemic disease characterized by the lymphoplasmacytic infiltration of affected tissues leading to fibrosis and obliterative phlebitis along with elevated serum IgG4 levels. Prior to this unifying hypothesis, a plethora of clinical manifestations were considered as separate entities despite the similar laboratory profile. The pathology can be observed in virtually all organs and may thus be a challenging diagnosis, especially when the adequate clinical suspicion is not present or when obtaining a tissue biopsy is not feasible. Nonetheless, the most frequently involved organs are the pancreas and exocrine glands but these may be spared. Immunosuppressants lead to a prompt clinical response in virtually all cases and prevent histological sequelae and, as a consequence, an early differential diagnosis from other conditions, particularly infections and cancer, as well as an early treatment should be pursued. We describe herein two cases in which atypical disease manifestations were observed, i.e., one with recurrent neck lymph node enlargement and proptosis, and one with jaundice. Our understanding of the pathogenesis of IgG4-related disease is largely incomplete but data support a significant role for Th2 cytokines with the contribution of innate immunity factors such as Toll-like receptors, macrophages and basophils. Further, macrophages activated by IL4 overexpress B cell activating factors and contribute to chronic inflammation and the development of fibrosis. We cannot rule out the possibility that the largely variable disease phenotypes reflect different pathogenetic mechanisms and the tissue microenvironment may then contribute to the organ involvement.