Normally tongue cancer
is treated with surgery and if required followed by radiotherapy. Only in cancer of the back part of the tongue (called base of tongue) is radiotherapy (RT) the primary treatment. Even in that case, the radiotherapy is generally combined with low dose chemotherapy
to enhance the effect of RT. The chemo is deferred only in cases where the patients tolerance and general condition are poor. If that is not the case, then i am afraid to say but your husband has been undertreated. As far as the nodule is concerned, there can be a number of reasons for the nodule, including infection or cancer. But since they have biopsied it, they must have thought it to be cancerous. Also, the fact that he has not been properly treated makes it more likely to be cancer. I am sorry to be worrying you more than you already are, but i'd rather tell you the truth. Wait for the biopsy
report and keep your fingers crossed.