I am sorry to hear that.
I think in english it is called Lymphoma i.e. a form of malignant growth of the lymph nodes and lymphatic system. There are several types including Non-Hodgkins Lymphoma and Hodgkins Lymphoma.
I doubt if they will let you fly again until after all the Chemo is over, but concentrate first on getting yourself better, and worry about that later
All the best, and good luck.