About 650 patients with non-parasitic cysts of the spleen were reported to 19783
and more than 1000 by 2002.1
Twenty per cent of splenic cysts remain asymptomatic. Left upper abdominal quadrant pain and tenderness are the most common clinical findings.2
A variety of radiological signs, because of adjacent organ displacement, have been reported.4
Details on the position, size, rim calcification, cystic component, presence of diaphragms, vascularisation and coexistence of other pathologies can be obtained by US and CT scans, which help pre-operative differential diagnosis.
Earlier classifications of splenic cysts were based on the cyst lining.5 6
A recent review combining the mechanisms of pathogenesis and clinical, macroscopic and microscopic characteristics classified cysts as parasitic or non-parasitic. The latter were further subdivided into primary, including congenital and neoplastic, and secondary, including traumatic and necrotic.7
A glistening white inner surface and trabeculation are considered features of primary epithelial cysts.7
The variability of the lining epithelium has been attributed to secondary alterations,8
and it has been proposed that when the lining epithelium is mesothelial, transitional or epidermoid, the cysts can be considered to be primary and congenital in origin.1 7
Stomata-like pores that connect the lumen of the cysts with the capillaries of the wall of the cyst or the adjacent splenic sinuses have been demonstrated by electronic microscopy.8
The influx of blood cells and fluid through these stomata has been implicated in the growth of cysts and in their symptomatology.8
The observed degradation of blood in the fluid of the cyst and the microscopic rupture of the cyst in the present case report are indications of preceding increased tension in the wall of the cyst. Increasing tension may also explain the observed abdominal pain and tenderness.
High concentrations of CA 19-9 have been found in the serum and fluid of cysts in association with immunoreactivity to CA 19-9 of the epithelium of primary spleen cysts.9
High concentrations of CEA and cancer CA 125 have also been found in the serum and fluid of primary epithelial spleen cysts.10
Tumour markers have been found despite the non-cancerous nature of the cysts.
The primary goal of surgical treatment is to remove the wall of the cyst and its lining without leaving cystic remnants in situ1
because recurrences have been reported following incomplete removal.11
En block excision of the spleen and intact cyst achieves this goal.
The second consideration is conserving splenic parenchyma to preserve splenic function. A partial splenectomy with complete removal of the entire cyst fulfils both of the above aims. However, a partial splenectomy that leaves the wall of the cyst in situ in juxtaposition with the splenic parenchyma, often referred to as ‘decapsulation’, carries the risk of cyst recurrence.
Excision can be performed by open laparotomy or laparoscopic techniques.1 11–13
Immunisation against pneumococci, Haemophilus influenzae B
and meningococci as well as antimicrobial prophylaxis is recommended.14 15
- Abdominal pain and tenderness were the main clinical findings.
- Degradation of blood in the fluid of the cyst and a microscopic rupture are indications of preceding increased tension.
- Raised serum CA 19-9 was found in the absence of malignancy.
- Dissection between the splenic parenchyma and the wall of the cyst proved safe.
- Excision without leaving cystic remnants prevented recurrence.
- Conservation of splenic parenchyma preserved splenic function.