Gross tumour volume



Gross tumour volume (GTV) is the primary tumour or other tumour mass shown by clinical examination, at examination under anaesthetic (EUA) or by imaging. GTV is classified by staging systems such as TNM (UICC), AJCC or FIGO. Tumour size, site and shape may appear to vary depending on the imaging technique used and an optimal imaging method for each particular tumour site must therefore also be specified. A GTV may consist of primary tumour (GTV-T) and/or metastatic lymphadenopathy (GTV-N) or distant metastases (GTV-M). GTV always contains the highest tumour cell density and is absent after complete surgical resection.

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