If the margins of resection at the time of the 2011 surgery were not involved by the tumor
, i.e were free (this will be in the biopsy
report), then the likelihood of the tumor recurring are remote. Also, more than 2 years have now passed without him having any problems. If such a cancer recurs, it generally comes back at the site of previous surgery or in the front of neck (not back). All these factors point towards this being an unrelated thing.You have not mentioned the duration of this lump. If it is recent it is even less likely to be cancer. I will suggest you to take Tab. Ciprofloxacin
500mg twice daily + Tab. Ibuprofen
1 thrice daily + Tab. Ranitidine
150mg twice daily for 7 days. If the lesion persists then get a FNAC (needle test) done by a pathologist from the lesion. Also, if you are a diabetic, get a blood sugar done, they maybe high, which can cause infections in this area.