Answer: Sclerosing Angiomatoid Nodular Transformation of the Spleen
The removed spleen measured 9 × 7 × 5 cm and weighed 133 g. Grossly, the lesion was a single, well-circumscribed, round-to-bosselated mass that measured 4 × 3.5 cm (Figure 2). At its periphery, multiple dark brown nodules were interspersed with stellate whitish fibrotic stroma. On microscopic examination, multiple angiomatoid nodules were seen submerged in a fibrotic stroma, with sharp demarcation of the lesion from the adjacent splenic parenchyma (Figure 2). The angiomatoid nodules were composed of complex disorganized vasculature with 3 distinct types of vessels that showed immunostain reactivity to CD34, CD8, and CD31. The lesion was consistent with sclerosing angiomatoid nodular transformation (SANT).
Cut surface of the spleen showing a bosselated mass with multiple dark brown nodules interspersed with stellate whitish fibrotic stroma.
Sclerosing angiomatoid nodular transformation of the spleen is an entity recently described by Martel et al1 and earlier under the term capillary cord hemangiomas by Krishnan et al.2 It is usually asymptomatic, seen in women in middle age, and diagnosed on imaging studies performed on patients for other reasons, usually in a background of malignancy. Patients may present to the surgeon with abdominal pain, raised erythrocyte sedimentation rate, fever, and anemia, requiring an extensive evaluation.
Hemangioma is the most common vascular tumor of the spleen and is distinguished from SANT by nuclear imaging. Histologically, it is composed of a single type of blood vessel similar to littoral cell angioma and lacks the distinctive angiomatoid nodular features seen in SANT.3 Epithelioid hemangioendothelioma is a rare splenic tumor of borderline malignant potential. It may be differentiated from SANT by the presence of cytological atypia and a low mitotic index.4
Splenic hamartomas contain structurally disorganized red pulp tissue and are differentiated from SANT by the absence of angiomatoid nodular pattern. Metastases to the spleen may also present as multiple nodules owing to exaggerated stromal response and are easily differentiated on histology. Kaposi sarcoma is usually seen in immunocompromised patients with human immunodeficiency virus or after transplant.
Splenectomy is uniformly curative in all patients with SANT. No recurrence has been reported to date.
Return to Quiz Case.
The Editor welcomes contributions to the Image of the Month. Manuscripts should be submitted via our online manuscript submission and review system (http://manuscripts.archsurg.com). Articles and photographs accepted will bear the contributor's name. Manuscript criteria and information are per the Instructions for Authors for Archives of Surgery (http://archsurg.ama-assn.org/misc/ifora.dtl). No abstract is needed, and the manuscript should be no more than 3 typewritten pages. There should be a brief introduction, 1 multiple-choice question with 4 possible answers, and the main text. No more than 2 photographs should be submitted. There is no charge for reproduction and printing of color illustrations.
Correspondence: Shankar R. Raman, MD, MRCS, 1770 Grand Concourse 12L, Bronx, NY 10457 (firstname.lastname@example.org).
Accepted for Publication: March 19, 2009.
Author Contributions:Study concept and design: Raman. Acquisition of data: Raman. Analysis and interpretation of data: Raman, Parithivel, and Niazi. Drafting of the manuscript: Raman. Critical revision of the manuscript for important intellectual content: Parithivel and Niazi. Administrative, technical, and material support: Raman, Parithivel, and Niazi. Study supervision: Parithivel and Niazi.
Financial Disclosure: None reported.
J Sclerosing angiomatoid nodular transformation (SANT): report of 25 cases of a distinctive benign splenic lesion. Am J Surg Pathol
1268- 1279PubMedGoogle ScholarCrossref
D Use of anti-factor VIII-related antigen (F8) and QBEN10 (CD34) antibodies helps classify the benign vascular lesions of the spleen. Mod Pathol
LM Splenic vascular tumors: a histologic, immunophenotypic, and virologic study. Am J Surg Pathol
827- 835PubMedGoogle ScholarCrossref