I am HER2 positive and have secondary breast cancer, liver mets. I am currently on herceptin and pertuzumab every 3 weeks. I have neuropathy in my hands and feet and more recently in my lips and tongue which is gradually getting worse. Over the last 4/5 months I have noticed cognitive changes - I forget things, I misplace things, I am easily confused and also struggle at times to remember words I am trying to say. Is this likely to be nerve damage as well or could it be something else I should be concerned about. I was first diagnosed in December 2019 and had chemotherapy, surgery, radiotherapy and have been on immunotherapy for over 5 years.