Splenic solid lesions

Benign

Inflammatory
- Sarcoidosis
Congenital
- Lymphangioma
  - Rare, benign, slow-growing
  - Mainly seen in childhood
  - Endothelium-lined cysts
  - Present as splenomegaly secondary to cyst enlargement
  - Lymphangiosarcoma can be found within the lesion
  - Splenectomy appropriate
- Primary cyst
Acquired
- False cyst
- Infarction
Vascular
- Haemangioma
  - Most common
  - Usually incidental
  - Usually solitary
  - Mostly <2cm (larger lesions associated with rupture)
  - Can be classified as either cavernous haemagioma or capillary haemangioma
- Hamartoma
  - Malformed splenic red pulp elements without organised lymphoid follicles
  - Usually <3cm
  - Spontaneous rupture has been described, but mostly not
  - Frequently splenectomy is necessary for a definitive diagnosis
- Littoral cell angioma
  - Multiple nodular masses leading to splenomegaly and hypersplenism
  - Usually seen as multiple masses of varying sizes that isodense on noncon CT, hypodense on early portal phase, isodense an delayed phase
- Sclerosing angiomatous nodular transformation (SANT)
Infectious
- Pyogenic abscess
- Fungal abscess
- Tuberculosis
- Hydatid cyst

Lymphoma
- See section on 'splenectomy for haematologic diseases'
Angiosarcoma
- Highly aggressive, poor prognosis
- Splenomegaly is common, and spontaneous rupture occurs in up to 25%
- Liver mets commonly found at presentation
- Can also present with haemolytic anaemia, ascites, or pleural effusions
- Linked with environmental exposures - thorium dioxide and monomeric vinyl chloride
Haemangiopericytoma
Splenic metastasis
- Most commonly melanoma, breast, lung
- Can also see ovarian, and rarely pancreatic, colon, stomach
- Radiological appearance variable
- Can see implants in serosal surface in peritoneal carcinomatosis
- Splenectomy can provide palliation of splenomegaly symptoms and prevent rupture, for carefully-chosen patients
- (relatively uncommon, maybe because of a lack of afferent lymphatics, but are found in up to 7% of cancer patients at autopsy)

Inflammatory pseudotumour (inflammatory myofibroblastic tumour)
- Uncertain aetiology
- Mainly incidental
- Spindle cell proliferation admixed with abundant inflammatory cells
- Most cases >10cm in diameter
- CT: hypodense mass with delayed enhancement, with a central scar without enhancement
- Final diagnosis usually made after splenectomy