Splenic hamartomas in children

Abstract

Splenic hamartomas (SHs) are uncommon, benign vascular lesions of unclear etiology and are mostly found incidentally on abdominal images, at surgery, or at autopsy. Since the first case description, in 1861, less than 50 pediatric SH cases have been reported in the literature. In this article, we have performed an analysis of all SH cases in children published in the literature to date and presented our case of an 8-year-old male with SH. These lesions in children were shown to cause symptoms more often than in the adult population. The observed SH sizes in children ranged from a few millimeters to 18 cm, and the symptomatic lesions were mostly larger or multiple. The most common clinical finding was splenomegaly. Signs of hypersplenism were present in children with a single SH larger than 4.5 cm (diameter range: 4.5-18.0 cm) and in those with multiple hamartomas, ranging from a few millimeters to 5 cm. Eighty percent of patients with available laboratory findings had hematological abnormalities such as anemia, thrombocytopenia, or pancytopenia. Other symptoms and signs included abdominal pain, recurrent infections, fever, night sweats, lethargy, growth retardation, and weight loss. The use of multiple imaging modalities may suggest the preoperative diagnosis of a splenic mass in children and determine the therapeutic approach. However, the final diagnosis of SH relies on histopathological evaluation. Surgery, including total or partial splenectomy (PS), is the mainstay of SH management. Although total splenectomy carries a greater risk of overwhelming post-splenectomy infection than PS it has remained the most performed surgical procedure in children with SH. In the majority of pediatric patients with symptomatic SH, resolution of symptoms and resolution or improvement of cytopenias occurred after surgical treatment.

Keywords: Clinical features; Histopathology; Pediatric; Radiological features; Splenic hamartoma; Splenoma; Treatment.

Figure 1

Possible etiopathogenesis of splenic hamartoma.

Figure 2

Gross appearance of splenic hamartoma. A nodular circumscribed unencapsulated lesion is visible on the cross-section, representing splenic hamartoma.

Figure 3

Microscopic images of the splenic hamartoma. A: Splenic hamartoma adjacent to normal splenic parenchyma was observed in the upper left of the panel, and compressed splenic parenchyma was observed in the lower right [hematoxylin and eosin (HE) × 50]; B: The lesion was composed of disorganized vascular channels lined by endothelial cells without significant cytological atypia (HE × 200); C: No mitosis or atypical cells were observed (HE × 400).

Figure 4

Immunohistochemical staining of the splenic hamartoma. A: CD8 was positive in the lining cells of vascular channels and in rare lymphocytes (× 200); B: Strong staining for CD31 was observed in the lesion (× 200); C: The lining cells of sinus-like spaces in the hamartoma were immunoreactive for CD34 (× 200).