When Rob was first diagnosed,i inevitably asked questions relating to possible future scenarios regarding his recovery and survival chances.
The head and neck specialist told us then that it was not common for oral cancer to spread downwards,partly due to removal of the lymph drainage network at surgery,and partly because the natural progression of the disease is more likely to take it up in to the brain and other close by structures.
Upper body scans done before surgery are to rule out spread of the cancer before diagnosis, and can influence treatment choices etc,which makes sense.

What i cant get my head round is how come so many people on this forum are being hit with lung mets,after treatment is finished,or even like Bren finding that it is the other way round and lung primaries are spreading to head and neck.,and if oral cancer doesnt commonly spread downwards why do so many have scans of their lungs done post tx?

Robs post tx scan done when his oral recurrance occured showed four tumours in his lungs but he had 62 lynph glands removed at surgery six months before, and a clear scan.