It is a diagnostic procedure, in which a piece of tissue from the mass (tumour) is taken out for pathological examination. It can usually be done by key-hole surgery. It is usually performed when other tests like needle biopsy fail to give a specific diagnosis.

Many a times, tumours occur in the middle of the chest (anterior mediastinum) or back side of the chest (posterior mediastinum). These are usually benign i.e. non-cancerous, but continue to grow none the less. Some of the m may be associated with various complications also. By enlarge, once diagnosed, they should be removed as early as feasible. The removal can be done by key-hole method with the help or robot or if the tumour is too large, an open surgery may be required. Complete resection usually cures these patients.