My father recently received a diagnosis of stage 4 esophageal cancer. I am seeking guidance on this site to better understand the implications of a "stage 4" diagnosis. However, based on the information provided here, my father's condition does not seem to align with the criteria for stage 4. We have been informed that he has a tumor in his esophagus and that cancer has been detected in a lymph node in his neck. He is currently undergoing further evaluation due to shadows observed on his lungs during an X-ray over the summer, which may be related to his work environment. This has not yet been confirmed as cancer. He brought this to the attention of his medical team during the consultation where he was informed of the stage 4 diagnosis, and they did not confirm that the cancer had spread to his lungs. Furthermore, there has been no mention of any other organs being affected, nor of more than this single lymph node in his neck. I guess my question is, is the staging purely based on spread of the cancer or is it also based on the aggressiveness? I don't want to give my father false hope by alerting him to this but also feel if it is stage 4, we haven't been given the full picture by medical teams?

Thank you