Sclerosing angiomatoid nodular transformation of the spleen: A case report of thrombocytopenia and a hypervascular splenic mass

Sclerosing Angiomatoid Nodular Transformation of the Spleen: A Diagnostic Conundrum

A splenic lesion often represents a diagnostic challenge due to relative scarcity and the broad differential diagnosis. Sclerosing Angiomatoid Nodular Transformation (SANT) of the spleen is usually encountered only incidentally. Although benign, patients with SANT often receive splenectomy, due to its rarity, diagnostic uncertainty and sometimes intimidating imaging morphology and size. Imaging features on computed tomography, magnetic resonance and positron emission tomography have a high diagnostic value for SANT and help differentiate this entity from other splenic lesions. When the imaging parameters are matched with core needle biopsy tissue analysis, further watchful waiting can be recommended in order to avoid splenectomy.

Rapidly growing sclerosing angiomatoid nodular transformation of the spleen

Sclerosing angiomatoid nodular transformation (SANT) of the spleen is a rare benign vascular lesion with unknown pathogenesis and no definitive pathognomonic radiological features. The majority of patients with SANT are asymptomatic, and the lesion is an incidental finding on cross-sectional imaging performed for unrelated reasons or during intra-abdominal surgery. However, in the symptomatic minority, abdominal pain is the most commonly reported symptom. SANT generally remains stable or has very slow growth, making it amenable to surveillance using serial cross-sectional imaging. Herein, we report the unusual case of SANT in a 30-year-old female with rapid growth from 6.0 × 5.6 × 4.4 cm to 8.0 × 6.6 × 7.2 cm over 21 months. Given the rapid growth, it was imperative to rule out malignancy. Thus, the patient underwent a laparoscopic total splenectomy. For SANT, splenectomy serves the dual purpose of diagnosis and definitive therapy.

Sclerosing angiomatoid nodular transformation presenting with thrombocytopenia after laparoscopic splenectomy - Case report and systematic review of 230 patients

Background

Sclerosing angiomatoid vascular transformation (SANT) is a rare vascular disease of the spleen, which is difficult to diagnose due to its pre-intervention appearance of malignancy. Case Report: An 85-year-old male was transferred to our clinic for thrombocytopenia and splenic mass. A contrast enhanced abdominal CT and MRI showed nodular lesions, the largest 50mm in diameter, and several areas of heterogeneous contrast field involvement in the spleen parenchyma. Laparoscopic splenectomy was performed with normal range of platelet level. The patient's postoperative course was uneventful and he was discharged on the 6th postoperative day. Histopathology revealed SANT. The patient is now in the 18 th month of remission with platelet levels within normal range and with no recurrence.

Results

Between 2004 and April 2020, a total of 230 SANT patients who underwent laparoscopic or open splenectomy or biopsy were reported in the literature. Most patients were female (52.1%), and the median age was 46 years (9 weeks-85 years). Most patients were asymptomatic (56%). Open splenectomy was performed on 166 patients (72.1%),laparoscopic splenectomy on 35 patients (15.2%) and laparoscopic partial splenectomy on 15 patients (6.5%). The median operation time and spleen weight were 143 minutes (88-213) and 260gr (68-2,720), respectively. Median follow-up time was 12 months (0-166). No recurrence was seen in patients undergoing total splenectomy.

Conclusion

SANT is an unusual disease of the spleen. In the light of this systematic review, a minimally invasive method for total or partial splenectomy,specifically laparoscopy, can be preferred as the treatment of choice.

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SANT is a rare, benign vascular disease of the spleen.

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The correct diagnosis of SANT pre-intervention or preoperatively is a significant for treatment.

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Laparoscopic splenectomy is curative treatment for SANT.