Chemo Vein

Hello,My mother has just finished her 4th chemo cycle with cisplatin and gemcitabine. She is due for at least 1 or 2 more cycles before the end of the year. She has stage 4 nonsmall cell lung cancer. She was on Tarceva for about a year before the cancer spread to her bones and her brain and she was switched from Tarceva to chemo.She's bit quite sick on the chemo, it's been tough for her with the fatigue and nausea. We noticed a new issue a few days ago though. She usually gets her chemo IV in her right hand. She's noticed that one of the veins in that hand is sticking up and it's very hard, like a rock. The nurse mentioned it could be phlebitis. Mum says it's quite sore to the touch.Has anyone else had the same problem? Is this serious or nothing to worry about?Many thanks,Helen