Lymph nodes & spleen, nonlymphoma

Spleen-vascular tumors

Sclerosing angiomatoid nodular transformation

Last author update: 1 January 2014
Last staff update: 2 June 2022 (update in progress)

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PubMed Search: Sclerosing angiomatoid nodular transformation of the spleen

Vijay Shankar, M.D.
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Cite this page: Shankar V. Sclerosing angiomatoid nodular transformation. website. Accessed January 28th, 2023.
Definition / general
  • Sclerosing angiomatoid nodular transformation (SANT): rare benign lesion of spleen with unknown etiology (Arch Pathol Lab Med 2013;137:1309)
  • Also called multinodular hemangioma
  • 2/3 women, mean age 48 years, range 30 - 60 years
  • Probably reactive, not neoplastic
  • May be splenic hamartomas which have undergone an unusual form of sclerosis, with a peculiar reactionary transformation of red pulp due to an exaggerated stromal response
Clinical features
  • Presents as asymptomatic splenic mass, abdominal pain or splenomegaly
Radiology description
  • Abdominal ultrasound, CT scans and MRI shows hypodense, sometimes multinodular splenic mass
  • CT or MRI with contrast cannot distinguish SANT from the surrounding spleen parenchyma
Radiology images

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Well circumscribed, highly vascularized

Expansible low density mass

5 cm tumor in hilus

Hypointensity of tumor

Splenic lesion at medial aspect

Lesion in lower spleen

Hypoenhancing mass

Prognostic factors
  • More aggressive if early age of onset
Case reports
  • Splenectomy is standard treatment
  • Indications for splenectomy included increase in mass size, marked splenomegaly or lingering suspicion of malignancy
Clinical images

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Solid tumor

Laparoscopic view

Gross description
  • Bosselated mass, solitary lesion, 3 - 17 cm, sharply demarcated from remaining spleen
  • Composed of coalescing red-brown nodules in dense fibrous stroma
Gross images

Case #364

Images hosted on other servers:

Well defined nonencapsulated lesion

Well demarcated,
dark brown mass

0.3 - 0.5 cm red-brown multinodular lesions

Splenic resection

Microscopic (histologic) description
  • Micronodular appearance of slit-like, round or irregular shaped vascular spaces lined by plump endothelial cells with interspersed ovoid or spindle cells
  • Smaller nodules surrounded by concentric collagen fibers
  • Also numerous red blood cells
  • Stroma contains myxoid to dense fibrous tissue with scattered myofibroblasts, inflammatory cells
  • No / minimal atypia, no / rare mitotic figures, no necrosis
Microscopic (histologic) images

Case #364

H&E images




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Angiomatoid nodules

Slit-like, round irregular shaped vascular spaces

Concentric rims of collagen fibrils

CD31 highlights the abundant vascular structures

CD34 highlights the capillaries

CD8 highlights occasional sinusoid-like spaces

CD68 highlights scattered single cells

Positive stains
Electron microscopy description
  • Small vascular spaces lined by endothelial cells with pinocytotic vesicles but no Weibel-Palade bodies
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