Splenic sclerosing angiomatoid nodular transformation in a patient with right renal carcinoma: A case report

Sclerosing angiomatoid nodular transformation mimicking a splenic metastasis from rectal cancer: A case report

Sclerosing angiomatoid nodular transformation (SANT) is a rare, benign lesion of the spleen. Preoperative diagnosis of SANT without pathological examination poses significant challenges, particularly in patients with a previous history of malignancy. The present study describes the case of a 53-year-old woman that presented to our institution with general fatigue and anemia. Based on a diagnosis of rectal cancer, the patient underwent curative surgery. Postoperatively, with minor leakage and the need for endoluminal drainage, the patient was monitored without adjuvant chemotherapy. A total of 1 year post-operation, enhanced computed tomography (CT) revealed a low-density lesion measuring 7 mm in the spleen. While metachronous metastasis was considered, there was no accumulation of 18F-fluorodeoxyglucose, and the levels of tumor markers, such as carcinoembryonic antigen and carbohydrate antigen 19-9, remained unremarkable. Regular surveillance through contrast-enhanced CT was performed. Over a period of 3 years, the tumor gradually increased to 25 mm. After a diagnosis of metachronous metastasis from rectal cancer, the patient opted for surgery, and laparoscopic splenectomy was performed successfully. Histopathological examination of multiple angiomatoid nodules in the fibrosclerotic stroma confirmed the diagnosis of SANT. The postoperative course of the patient was uneventful. In cases of SANT following a prior malignancy, splenectomy should be considered for both diagnostic and therapeutic purposes.

Two Rare Benign Lesions on 18F-FDG PET/CT: Peliosis Hepatis and SANT

Peliosis hepatis (PH) and sclerosing angiomatoid nodular transformation of the spleen are uncommon benign lesions. Diagnosis can be difficult in some patients. Herein, we present the case of a 28-year-old woman referred with abdominal pain who had spleen lesions. 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography revealed multiple non-FDG avid lesions in the liver and hypermetabolic lesions in the spleen. In addition, abdominal magnetic resonance imaging was performed. Histopathology revealed sclerosing angiomatoid nodular transformation in the spleen and PH in the liver.

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.