Question asked by: 
Attendee at Being Together Plymouth
Date asked: 
Oct 2015
Is proton therapy ever appropriate in ovarian cancer?
Proton therapy is a new radiotherapy that’s very expensive, and is pretty much unavailable to most of us in Europe. It's used in tumours resistant to radiotherapy, but there is no data that ovarian cancer is resistant.
Response by Guest experts from Being Together Plymouth

The question is radiotherapy, and it is just high dose x-rays and is quite good at treating cancers and shrinking them down. Before the advent of carboplatin, ladies used to have, what was called 'whole abdominal radiotherapy'. So basically the whole abdomen and pelvis would be bathed by radiotherapy, from the machine on the outside. The introduction of carboplatin, showed the results to be similar to whole abdominal radiotherapy, but less toxic. There was then a switch from whole abdominal radiotherapy to carboplatin, and the other chemotherapies.

Radiotherapy now, pretty much in all the world, is used in palliative settings. So you have some bleeding from the vagina or one lump that you want to treat with radiotherapy, and that is very good at treating that one lump. As we have gone from whole abdominal radiotherapy from chemotherapy, there is a question, I think, as to whether there is room for more limited, smaller volume radiotherapy in addition to chemotherapy. We know that whole abdominal radiotherapy has been replaced by chemo. Chemo does the job, but if we give pelvic radiotherapy, just to the pelvis, does it give you a further advantage? That is not an answered question. 

Practice varies from country to country, centre to centre. There isn’t the literature to guide us on radiotherapy to the pelvis or the evidence there. The unanswered question is, ‘Should we now change the standard after surgery, that selected patients have chemotherapy plus radiotherapy to the pelvis?’ If you have disease by the liver, giving radiotherapy to the pelvis is meaningless. It’s for patients who have what is called stage II disease, where the disease is really limited to the pelvis.

Proton therapy is just a fancy new radiotherapy that’s very expensive, and is pretty much unavailable to most of us in Europe. It is pretty useful to tumours resistant to radiotherapy, but there is no data that ovarian cancer is resistant to ordinary radiotherapy. So I wouldn’t go down the route of proton therapy. If anything, I would explore the road of ordinary radiotherapy to the pelvis.