( CNN ) A British boy whose parents were once arrested for pulling him out of a hospital now appears to be free of cancer , a family spokesman said Monday . Ashya King , 5 , had proton beam therapy and appears to have had no cancer for months , Jonathan Hartley said . Is proton therapy the 'magic bullet ' for cancer ? The family is in Spain . Ashya 's parents , Brett and Naghmeh King , are afraid to return to the United Kingdom for fear of arrest , though they are in talks to return , Hartley said . Britain 's Crown Prosecution Service said in September that it would not arrest the parents . That announcement came after they were arrested in Spain while authorities decided whether to charge them and extradite them to Britain . The Kings had serious concerns about the medical treatment that Ashya was receiving at University Hospital Southampton . So they defied doctors ' orders and took him out . Dr. Hernan Cortes Funes , who 's overseeing Ashya 's treatment , agrees with the assessment that Ashya is cancer-free , he told CNN on Monday . Still , there is a high chance of recurrence , he said . Funes gave CNN details : . In August , Ashya had surgery in Britain to remove the tumor . The kind of tumor Ashya had is very aggressive and can often relapse in the brain or the spinal cord . The standard treatment is radiotherapy in the brain and spinal cord , which can cause serious side effects or even death . Ashya 's parents wanted to instead do a new proton therapy , which is conducted by only a few sites in Europe . One is in the Czech Republic . Since Ashya was born in Marbella , southern Spain , his family contacted a hospital there and then took Ashya to have proton therapy in Prague in September . The next month , the boy began rehabilitation in Marbella . Initially after the proton therapy , Ashya was mute and had no movement . But after three months of intensive treatment , he can walk generally unaided . He has also been swimming and playing with toys , Funes said . His family comes to see him every day . Ashya has difficulty speaking but continues to improve . He can say a few words , and he can give simple answers when asked questions such as whether he is hungry . Medical officials in Madrid will make a molecular profile of the tumor that was removed to help identify the risk of relapse . Doctors have requested a sample from Southampton . The surgery conducted in Southampton was excellent , Funes said .
Ashya King , 5 , had proton beam therapy , Jonathan Hartley says . The British boy appears to have had no cancer for months , he says . Comment: