5 Implications for the NHS
5.1 Patients who receive treatment with trastuzumab should be monitored for the possibility of cardiotoxicity.
5.2 The manufacturer estimated the gross impact of providing trastuzumab plus paclitaxel instead of paclitaxel alone and trastuzumab monotherapy to be approximately £17 million per annum. This estimate is based on the following assumptions: HER2 status is assessed in 20,000 patients with metastatic disease at a cost of £21 per test; 1600 patients receive monotherapy at a cost of £5,300 per person; 450 patients receive combination therapy costing an additional £15,500 to provide trastuzumab and paclitaxel instead of paclitaxel alone; each person receives four cardiac tests at a cost of £580 for each set of four tests. (Overall calculation: [20,000 x £21] + [1,600 x £5,300] + [450 x £15,500] + [1,600 x £580]).