Conversation: The conversation between human and AI assistant.
[|Human|] I have a lump on my back that feels like a bubble of gas or water, about the size a baseball. It moves around a bit when I put presure on it, or when I lie down. It does not hurt much and it is under my left shoulder blade...What is it. I am 50 years old in general good health.
[|AI|]  Hello and welcome to Chat Doctor, A mobile lump which feels like gas, or fluid filled like can be a cyst. However, certain investigations are required before management can be planned. Imaging preferably an ultrasound of the back is required to assess the site and origin of the lesion. After assessing the site and origin, an aspiration cytology can be planned. In this investigation, cells are aspirated using a needle, stained and examined microscopically. Management/ treatment can be planned after investigations. Thanks and take care Chat Doctor.