I Am A 63 Yr Old Male,that Has Had Tongue

I am a 63 yr old male,that has had tongue cancer and then neck cancer. I had radiation and chemo for head and neck within the last 4 months.I just had a cat scan for follow up and now have been told I have a spot on my left lower lung,that measures 1.3 x1.4 cm. Is it likely that the original cancer has metastasized to my lung now.?????