We have known for some time that treatment results can be predicted through PET scanning after about 2-3 months, but now it looks as if scanning even earlier in the treatment course can predict a good result with greater certainty. Furthermore, the early timing means it is possible to adjust the treatment plan depending on the scanning result," said Martin Hutchings, Consultant at the Department of Haematology at Rigshospitalet,
The study has just been published in the prestigious American Journal of Clinical Oncology. In the study a number of researchers from Denmark, the US and Poland monitored patients with Hodgkin lymphoma (Hodgkin's disease) and found that a good scanning result so early in the treatment gives patients at least a 95% chance of being cured.
Martin Hutchings has headed the study and he hopes that the results will lead to new studies to investigate the effects and to adapt treatment according to the results of early PET scanning.
More patients are surviving cancer"The good news is that we've got so good at treating certain types of cancer that more and more patients are surviving and far fewer die of the original sickness. However, the bad news is that many of the patients who do survive risk serious late side effects from their treatment. They risk heart disease or another cancer disease which perhaps won't show itself for 10, 15 or even 20 years. Therefore, we want to be able to identify and help patients who only need mild chemotherapy and who can bypass radiotherapy," said Martin Hutchings, and he continued,
"We can see this especially in young patients with Hodgkin's disease, who should have prospects of a long and good life after completing their treatment. Unfortunately they risk life-threatening sequela which don't show up until later on in life. Of course we hope that by scanning patients so early in their treatment we can dose treatment for the individual patient. With a very early assessment of the effects of treatment, there is every indication that it is still possible to change the treatment plan and intensify doses after the first cycle of chemotherapy, or carry out treatment over a longer period if necessary.
"In my view, our attempts to optimise and tailor treatment as much as we can are a very natural step. But it is a very fine balance. This is because while on the one hand we are trying to make treatment milder, but on the other hand we also still have to offer rapid and effective treatment with the greatest possible chance of survival. The same applies with regard to intensifying treatment for the few patients for whom treatment is not working so well, without over-treating the majority of patients for whom treatment is working and who will be cured.
New studies requiredResearchers have looked at Hodgkin lymphoma first because we know that the cancer cells in this disease are very sensitive to chemotherapy. However, the method could also be relevant in treatment of other cancer diseases.
"I can see a lot of perspective for treatment of cancer patients. In fact, our good results have already led to the Polish health authorities introducing early PET scanning as standard in treatment of Hodgkin's disease, although this has not been done in Denmark," said Martin Hutchings.
In an equally new European study, also published in the Journal of Clinical Oncology and also with Martin Hutchings on the list of authors, a number of researchers have examined the possibilities for a more effective and gentle treatment for Hodgkin lymphoma. Here they applied an early PET scanning after two cycles of chemotherapy and the scanning results were used as a guide for subsequent treatment. However, even though the results have shown good survival rates, and about 90% of patients were cured without using radiotherapy, there was a marginal, but slightly larger, risk of a relapse of the disease than if the patients had undergone radiotherapy.
"So, the question is whether the results of the study would have been different and better if, in the study, we had carried out PET scanning after the first cycle of chemotherapy and at an even earlier phase of the treatment. Perhaps we would then have been able to adjust the treatment according to the results with a greater degree of certainty of a good prognosis. Time will tell, and therefore it is also clear that more and even more comprehensive studies are required, including experiments with this scanning as part of the design, if we are to have any chance at all of changing the guidelines for treatment in Denmark and in similar countries," said Martin Hutchings.