Mnemonic

The 4 Ts of an Anterior Mediastinal Mass

A mnemonic for the differential diagnosis of an anterior mediastinal mass.

Expansion

Thymoma, Teratoma, Thyroid (retrosternal), Terrible lymphoma

Expansion

  • T - Thymoma and other thymic tumours
  • T - Teratoma and other germ cell tumours
  • T - Thyroid, that is a retrosternal extension of a goitre
  • T - Terrible lymphoma

The anterior mediastinum is the narrow space between the sternum and the pericardium, so it contains little more than the thymus, fat, lymph nodes and the internal thoracic vessels. Anything filling it out on a lateral chest radiograph therefore comes from a short list.

Learning note

Pair this with the posterior mediastinum, where neurogenic tumours predominate, and the middle mediastinum, where the commonest masses are lymphadenopathy, bronchogenic cysts and vascular abnormalities.