Staging using the tumour–node– metastasis (TNM) sy

Staging using the tumour–node– metastasis (TNM) system

The TNM staging system for prostate cancer is shown in Figure 84.14 . /uni25CF T1a , T1b and T1c . These are incidentally found tumours in a clinically benign gland after histologi - cal examination of a prostatectomy specimen. T1a is a tumour involving less than 5% of the resected specimen; these tumours are usually well or moderately well di ff er - entiated. T1b is a tumour involving >5% of the resected specimen. T1c tumours are impalpable tumour s found fol - lowing investigation of a raised PSA. /uni25CF T2a disease presents as a suspicious nodule ( Figure 84.15 ) on rectal examination that is confined within the prostate capsule and involves one lobe. /uni25CF T2b means that the cancer is in more than half of one side of the prostate gland, but not both sides. /uni25CF T2c means that the cancer is in both sides but is still inside the prostate gland. /uni25CF T3 tumour extends through the capsule: /uni25CF T3a, uni- or bilateral extension; /uni25CF T3b, seminal vesical extension. /uni25CF T4 is a tumour that is fixed or invading adjacent structures other than seminal vesicles – levator muscles, external sphincter, rectum or pelvic side wall. Summary box 84.6 The natural history of prostate cancer /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF

T0 T1 T2b T2a T2c T4 T3 Figure 84.14 Tumour–node–metastasis staging system for prostate cancer. This depends on the stage and grade of disease: T1 and T2 The progression rate of well-differentiated T1a prostate cancer is very low: 10–14% after 8 years. For moderately differentiated tumours, the rate is about 20%. For T1b and T2 tumours, the rate is in excess of 35% T3 and T4 (M0) About 50% progress to bony metastases after 3–5 years M1 The median survival of men with metastatic disease is about 3 years