Suggest Treatment For Chest And Back Pain While On Radiotherapy

my dad has stomach cancer and has had chemotherapy and a stent fitted but seems to have had bad chest and back pains since the stent was fitted even more so now he has had radiotherapy. The tumour has reduced significantly and the lymph nodes are back to normal. The consultant says the chest and back pains may be because the stent may have been affected by the radiotherapy. He is sick every day and is in agony. His next scan is not for another 4 weeks and fear he may not have to energy to last this long. Please can you help i cannot bear to see him in this pain. He has a water infection and is living on morphine.