Redness below the collarbone is not a sign of pre-cancer. If there is redness above the clavicle, it may be caused by bacterial infection, pay attention to see if there are hard nodules, redness, swelling and pain. If the disease is caused by bacterial infection, you need to take oral antibiotic treatment, a generation of cephalosporin or second-generation cephalosporin can be, such as cefradine or cefixime. While paying attention to the period of taking antibiotic treatment, is the redness and swelling reduced in scope, is it improved? If the redness and swelling increase in size, or even if an abscess forms, surgery is needed to remove the abscess. Cancer usually does not show localized redness and swelling, but only localized nodules. The nodules are usually hard and can be examined by ultrasound or puncture for pathology. If the pathology finds cancer cells, then it is cancer.