Hello and welcome. sorry you are having this difficulty. The lobectomy was a year ago? I would inquire about this ongoing issue post surgery. Here is general information on that type of surgery https://www.webmd.com/lung-cancer/lobectomy-lung-surgery#1. Generally, your health going into the surgery helps determine if you will have any complications after. Typically though, coughing when talking (and not when silent) is a vocal cord issue. Actually, something to talk to your doctor about as well is Gerd which can cause this phenomenon. When is the last time you have talked to a doctor about this?