Thymolipoma

Epidemiology

This rare tumour may occur at any age, but is most common in young adults.

Clinical features

Most cases are asymptomatic and are found incidentally. They may mimic cardiomegaly1. About 7% of cases are associated with myasthenia gravis. Rarely, there is associated aplastic anaemia or Graves disease.

Histopathology

Mature adipose tissue is interspersed with residual thymic tissue. There is a single report of a type B2 thymoma arises within a thymolipoma2.

Differential diagnosis

Lipoma of the thymus is devoid of an epithelial component.
Liposarcoma

Management and Prognosis

Local excision is curative.

References

0 Tumours of the Lung, Pleura, Thymus and Heart. WHO Classification of Tumours. IARC Press 2004.

1 Almog C, Weissberg D, Herczeg E, et al. Thymolipoma simulating cardiomegaly: a clinicopathological rarity. Thorax 1977; 32:116-20

2 Argani P, de Chiocca IC,Rosai J. Thymoma arising with a thymolipoma. Histopathology 1998; 32:573-4

This page last revised 17.1.2006.