Lymph nodes & spleen, nonlymphoma
Spleen-vascular tumors
Sclerosing angiomatoid nodular transformation
Author: Vijay Shankar, M.D.
Last author update: 1 January 2014
Last staff update: 2 June 2022 (update in progress)
Copyright: 2003-2023, PathologyOutlines.com, Inc.
PubMed Search: Sclerosing angiomatoid nodular transformation of the spleen
Table of Contents
Definition / general | Epidemiology | Pathophysiology | Clinical features | Radiology description | Radiology images | Prognostic factors | Case reports | Treatment | Clinical images | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Electron microscopy description | Differential diagnosisCite this page: Shankar V. Sclerosing angiomatoid nodular transformation. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/spleensclerosingangiomatoid.html. 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
Epidemiology
- 2/3 women, mean age 48 years, range 30 - 60 years
Pathophysiology
- 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
Images hosted on other servers:
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
- 11 year old boy with SANT and inflammatory pseudotumor-like areas (Indian J Pathol Microbiol 2011;54:829)
- 23 year old woman treated by laparoscopic partial splenectomy (Wideochir Inne Tech Malo Inwazyjne 2011;6:249)
- 23 year old woman treated with laparoscopic splenectomy (J Korean Surg Soc 2011;80:S59)
- 38 year old man with laparoscopic splenectomy (IJCRI 2012;3:34)
- 44 year old man with splenic mass (Case #364)
- 53 year old woman (Int J Surg Case Rep 2012;3:492)
- 65 year old man with SANT masquerading as sarcoma metastasis (Rare Tumors 2010;2:e45)
Treatment
- Splenectomy is standard treatment
- Indications for splenectomy included increase in mass size, marked splenomegaly or lingering suspicion of malignancy
Clinical images
Images hosted on other servers:
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,
unencapsulated,
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
CD8
CD31
CD34
Images hosted on other servers:
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
Differential diagnosis
