Brief Answer:
side effects are usually manageable

Detailed Answer:
Hi
Thanks for your query.

For rectal cancer upfront radiation with oral chemotherapy is a standard for most patients. Usually it is well tolerated if the patient is in active health without too many other illnesses. Only age on the higher side will not make it difficult.

Common side effects are pain, irritation in rectum with or without discharge or frequent small volume stools. Sometimes abdominal pain or urinary discomfort or burning. As his tumor is in upper rectum/ lower colon, side effects should be less.

Hope this helps.
Regards

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