Clinicopathological features of sclerosing angiomatoid nodular transformation of the spleen.

Purpose: To explore the clinicopathological features of sclerosing angiomatoid nodular transformation (SANT) of the spleen.

Methods: The clinicopathological data of 26 SANT patients were analyzed.

Result: There were 15 men and 11 women, aged 23-62 years (mean: 43.9 years; median: 43 years). Twenty patients were found during health check-ups. Magnetic resonance imaging had significantly higher specificity than other imaging modes in the diagnosis of SANT. Macroscopically, the lesions were gray-red and gray-white, along with well-demarcated nodules. Microscopy showed multiple angiomatoid nodules embedded in hyperplastic fibrous tissues and dense collagen fiber; the angiomatoid structures inside the nodules had varied morphology. Patchy and nodular fresh and old hemorrhages were observed in each lesion. Proliferative fibroblasts were seen in the stroma, along with infiltration of a few mixed inflammatory cells. Serum tumor markers were negative. Fourteen patients (53.8 %) had benign or malignant lesions in other parts of the body, including the liver, kidneys, and adrenal and pituitary glands which were similar to von Hippel-Lindau (VHL) syndrome. The reasons for occurrence of SANT may be as follows: hemangioma/lymphangioma or splenic congestion with extensive hemorrhage and secondary changes.

Conclusions: SANT is a rare benign vascular lesion with some clinical manifestations similar to VHL syndrome. Patients have good prognosis after tumor removal.