Hi, my father had a 1.5 cm squamous cell Stage 1 cancer removed with a lobectomy in April of the upper right part of the lung. He went for his first check up in August. The xray appeared clear and the doctor was very happy with his quick recovery. He has now gone for another xray in November and the doctor and spotted a "fullness in the hylem of the middle lung". My father also has moderate COPD and has a cough with shortness of breath, which could be the result of having the surgery. He was a smoker for 50 years and is 76 years old. The doctor is ordering a CATS scan. What could this now be? Could it be the cancer reaccurring somewhere else or could it be pnemonia or just nothing?