Bump on dog's lip

this started out as a small bump and has been getting bigger and bigger. not sure if it needs vet appointment.

Hello!  Your dog appears to have a lump on their lip.  This may be a tumour, benign or malignant, or may be related to the papilloma virus, which can be transmitted between dogs (ie is infectious).   We would advise showing it to your vet to decide what is most likely and how best to handle it.  It could be helpful to ask them about transmission to other dogs if there is a chance that it may be viral (you could search in the blog for an article called 'Why does my dog have warts?' to find out more about that possibility). Please do let us know how you get on!