If the spleen is enlarged and irritates the spleen capsule as a result, patients usually feel a feeling of pressure or even severe pain. If an enlarged spleen is suspected, the easiest way to clarify this is by means of imaging procedures. In the case of splenic cysts, a distinction can be made between true cysts and pseudocysts. If you experience acute pain in the upper abdominal region, you should always think of a cyst rupture.
Cysts are encapsulated, fluid-filled masses in a tissue or organ. There may be one or more chambers in the interior. A distinction is made between true and pseudocysts. True cysts are lined with their own layer of cells, whereas pseudocysts are only surrounded by connective tissue [1]. Possible causes of cysts are listed in Overview 1 .
Symptoms and diagnosis depend on the type and location of the cyst. Those close to the surface of the skin, such as on the breast, are often seen or felt due to swelling. However, if internal organs such as the kidneys or liver are affected, the diagnosis is usually accidental, for example during an imaging examination. The main localizations can be found in Overview 2.
Cysts can be solitary or multilocular. Genetic changes as the cause of cysts in syndromes are possible, e.g. in Hippel-Lindau syndrome or Autosomal Dominant Polycystic Kidney Disease – ADPKD as a common hereditary disease that affects around 1 in 1000 people.
Congenital splenic cysts are generally unproblematic as long as they do not exceed a certain size and do not displace other organs or cause complications such as bleeding [2]. A healthy spleen is insensitive to pain. However, if the organ is enlarged and irritates the spleen capsule, patients usually experience a feeling of pressure or even severe pain. An acute onset of pain in the upper abdominal region should always suggest a cyst rupture [4]. If the consecutive enlargement of the spleen leads to anemia, patients often have a pale complexion, are tired and feel physically exhausted. If the number of thrombocytes also falls, nosebleeds or minor bleeding of the oral mucosa occur more frequently. An enlarged spleen can also reduce the number of white leukocytes required for immune defense. This makes the body more susceptible to infectious diseases.
An enlarged spleen under the left costal arch can be detected on palpation and confirmed by imaging procedures such as sonography, computerized tomography or magnetic resonance imaging; the resulting erythro- or leukopenia can be verified in the laboratory examination.
Various cystic lesions should be considered in the differential diagnosis [5], listed in Overview 3.
X-rays can contribute little to the diagnosis of splenic cysts. Pronounced wall calcifications are occasionally recognizable as arch-shaped shadows in the left upper abdomen.
Computed tomography scans allow the exact size of the spleen to be determined in all planes. The detection of parenchymal changes, especially calcifications, is very successful. Cysts can be delineated very well and density measurements allow conclusions to be drawn about the protein content of the cysts.
Magnetic resonance imaging is also very well suited for determining the size of the spleen and detecting various masses. However, smaller calcifications can escape detection.
Sonography is very good at detecting structural changes in the spleen. However, determining the overall size of the spleen in the case of splenomegaly can be somewhat more complex compared to the other cross-sectional imaging techniques
Case study
The case study shows the course over several years of an initially large and symptomatic cyst of the spleen. The patient, who was 50 years old at the time of the initial diagnosis and in good general health, complained of undulating pain and a feeling of pressure in the left upper abdomen. There were no relevant concomitant diseases or a history of trauma. A particular exposure for parasitic diseases was not known, the usual laboratory values showed no relevant deviation from the norm. An MRI of the upper abdomen was requested in March 2015 to clarify the diagnosis. An uncomplicated cyst measuring over 9 cm in diameter was detected in the enlarged spleen (Fig. 1A and B). The patient refused invasive treatment. Sonographic checks three months after initial diagnosis and in August 2018 did not document any significant change in size and structure (Fig. 1C) . An MRI of the upper abdomen in February 2024 showed a significant reduction in the size of the cyst and, with a predominantly inhomogeneous hypointense internal structure in all sequences, a pronounced calcification was suspected (Fig. 1D and E). There was no triggering event in the sense of trauma or inflammation. Abdominal computed tomography four weeks later confirmed the significant reduction in size of the splenic cyst and subtotal, coarse calcification. Further small parenchymal calcifications were detectable (Fig. 1F and G).
Take-Home-Messages
- Cysts are encapsulated volumes of fluid that can occur solitary or multiple in various tissues and organs.
- A distinction is made between true and pseudocysts.
- The cysts are usually asymptomatic, but can cause a feeling of pressure and pain depending on their size and location.
- Mostly benign, inflammatory complications, bleeding, ruptures or degeneration are possible.
- Sonography, computer tomography and magnetic resonance imaging are suitable for diagnostic imaging.
Literature:
- “Cysts”, https://medikamio.com/de-de/krankheiten/zysten,(last accessed 04/17/2024)
- “Splenic cyst”, www.klinikum.uni-heidelberg.de/erkrankungen/milzzyste-200073,(last accessed 17.04.2024)
- Kala PS, et al: Primary epithelial splenic cyst: A rare encounter. Indian J Pathol Microbiol. 2019; 62(4): 605-607.
- Res LC, et al: Spontaneous rupture of a non-parasitic splenic cyst. BMJ Case Rep 2019 Oct; 12(10).
- Warshauer DM, Hall HL: Solitary splenic lesions. Semin Ultrasound CT MR 2006; 27(5): 370-388.
InFo ONCOLOGY & HEMATOLOGY 2024; 12(3): 34-36
