Sclerosing Angiomatoid Nodular Transformation of the Spleen: A Systematic Review

Sclerosing angiomatoid nodular transformation of the spleen (SANT) is a rare benign tumor. Its epidemiological and morphological characteristics remain unknown. The main objective of this work is to reveal the epidemiological, biological and morphological characteristics of a SANT.

Seventy-three publications were included in this review describing 188 cases of SANT. The average age of the patients was 45.9 years and the gender ratio was 0.66. SANT was found incidentally in 60% of the cases. In most cases (85.6%), there was no anomaly in biological tests. Abdominal ultrasound showed a hypoechoic mass which is heterogeneous. Abdominal CT scan was performed in 49.5% of the cases. It showed a hypodense (92%), heterogeneous (92%) mass. After contrast agent injection, the spoke wheel aspect was observed (100%). In all cases, the density of the mass was lower than that of the non-tumoral splenic parenchyma. Abdominal MRI was performed in 23.9% of the cases. After dynamic injection of Gadolinium, it showed the same aspect as in the CT scan. All patients were operated either immediately (88.2%) or after clinical and/or radiological changes during monitoring (9.6%).

The diagnosis of SANT remains a real challenge for the clinician and the radiologist. Establishing the differential diagnosis with other rare tumors is important in order to develop a standardized management protocol.