Since 2009, a new procedure has revolutionised the way that the Mackay Memorial Hospital’s Department for Paediatric Haematology-Oncology, in Taiwan, has treated acute lymphoblastic leukaemia (ALL), which is the most common cancer among children. The hospital has led the way in using intrathecal chemotherapy as the treatment of choice for ALL, which affects the wellbeing of one in every four children who have cancer.
The hospital recently reported that the treatment improves child cancer wellness by decreasing the rate of central nervous system relapses and avoiding the long-term pathological conditions that prophylactic cranial irradiation can cause. This latter treatment, as well as intrathecal chemotherapy injections, is the traditional method of choice, said department director Liu His-che, but the Mackay Memorial Hospital dropped the use of prophylactic irradiation in 1999. Prophylactic irradiation can cause serious complications and chronic conditions, including brain tumours, neurocognitive deficits, endocrinopathy (which is a hormone imbalance) and stunted growth.
According to Liang Der-cherng, an attending physician at the department who has headed the establishment of a national treatment protocol for childhood ALL since 1993, the lumbar puncture that intrathecal chemotherapy requires is usually done at the time of diagnosis, but this has also been delayed in the new procedure. Liang explained that if you perform a lumbar puncture before the chemotherapy drugs have a chance to eliminate the circulating cancer cells, cancer cells in the blood can be taken to the brain, which could inadvertently complicate the disease.
Liu commented, ‘Mackay has treated 152 children with ALL since 1999 with treatment that omitted prophylactic cranial irradiation and nearly 90% of them were cured, with no cases of isolated central nervous system relapses and a combined central nervous system relapse rate of just 1.4%.’ She added that measuring the level of minimal residual leukaemic cells, in order to accurately predict the risk of relapse, and determine and adjust the intensity of therapy, has also furthered the hospital’s success in treating ALL. ‘It’s better to have a minimal residual leukemia level lower than 0.01%, which is one leukemic cell among 10,000 normal cells,’ Liu said. However, the measurement is, unfortunately, not covered by National Health Insurance.