The impact of centralised care of younger AML patients on treatment results: a retrospective analysis of real-world data from a national population-based registry
Abstract
The care for younger patients with acute myeloid leukaemia (AML) requires fully equipped medical facilities that have routine experience with the management of this aggressive disorder. Two independent analyses of real-world data from the United States (US) have showed a lower early mortality after an intensive chemotherapy when the patients are treated in high-volume centres or in National Cancer Institution-Designated Cancer Centres (NCI-CC) compared to the treatment in low-volume or in non-NCI-CC centres [1,2].
The size and experience of the centre has also a statistically significant effect on early mortality after allogeneic transplantation of haematopoietic stem cells (HSCT), as shown by a US study where a lower 100-day mortality after allogeneic HSCT at centres with a higher patient-per-physician ratio was observed [3]. These results were confirmed by a retrospective analysis of the European Group for Blood and Marrow Transplantation (EBMT), in which 100-day survival after unrelated allogeneic HSCT was improved at centres performing >= 20 transplants per year [4].
The reduction in mortality is probably related to a better management of serious complications that require an intensive supportive care. Ross et al. showed a lower 30-day mortality for three common medical conditions, including pneumonia and heart failure, when treated in higher-volume hospitals [5].
On the other hand, the centre effect on the long-term survival of patients with AML is controversial. The positive impact of the academic status of centres on the long-term survival was shown in a retrospective analysis published by Bhatt et al. [6].
However, the effect of hospital size on long-term survival has not been demonstrated in the group of younger patients with AML treated in England and Wales in 1984-94 [7]. Clinical trials of the American cooperative groups SWOG/ECOG-ACRIN report a positive centre effect on complete remission (CR) rate after induction chemotherapy, but the difference in overall survival (OS) was also not statistically significant [8].
In the Czech Republic, the care of younger patients with AML is centralised in seven academic hospitals, which provide care to all 10.5 million inhabitants of this Central European country with a system of compulsory health care insurance. All patients with newly diagnosed AML are referred from local hospitals to the academic centres for therapeutic decision and treatment.
The academic centres cooperate within the CELL group (CzEch Leukemia study group for Life) and maintain a detailed real-world database of AML patients DATOOL-AML (Database of Acute Leukemia-Tool) where all intensively and non-intensively treated subjects are registered. We analysed the results of treatment of younger patients with AML aged 18-59 years over the years 2007-2019 in the Czech academic centres and compared them with those achieved in clinical trials and in other relevant hospitals abroad.
Our analysis evaluated principal outcomes of care of AML patients in the Czech Republic and also attempted to determine factors that affect the results of treatment. The analysis is intent to treat and includes all the registered AML patients treated intensively and non-intensively.
In five Czech centres, >=10 younger patients with AML (range 12-31 pts./year) were treated annually, and allogeneic HSCT was routinely performed in the reporting period. In the two remaining smaller centres, allogeneic HSCT was not performed, and <10 younger patients with AML (range 6-8 pts/year) were treated annually.
One of the two smaller centres has been recently established in the University Hospital Ostrava and nowadays is undergoing rapid development including the effort to launch their own allogeneic transplantation program. The other smaller centre is based in Prague and closely cooperates with the other high volume centre in the capital city.
All patients from the two low volume academic hospitals indicated for allogeneic HSCT were referred to the high volume academic hospitals.