I would think that the chemo-radiation in this case is to prevent a stray cell from getting into the lymphatic or blood circulatory system an migrate to other parts of the body. The number of chemo treatments depend on the dosage. There are patients who get 3 “big bags” (which my husband had) or a smaller dose each time but with more treatments. The same applies to radiation. My husband got 70 grays (units of radiation) for a total of 35 days, I.e. 2 grays each day , but in his subsequent radiation treatments, each time he got 20 grays in total over 5 days, I.e. 4 grays each day. So he actually got a stronger dose for his subsequent treatments. You may want to ask the doctors about this.