Adolescents with acute lymphoblastic leukaemia: emerging from the shadow of paediatric and adult treatment protocols

Transplants in Adult ALL--? Allo for everyone

The large MRC/ECOG adult acute lymphoblastic leukemia (ALL) study establishes the value of sibling donor allogeneic transplant in standard-risk patients demonstrating superior outcome to conventional chemotherapy. The small but significant number of patients having matched unrelated donor (MUD) transplants on this study protocol appear to do well, and may establish the value of such an approach for those without a sibling. Reduced-intensity conditioning (RIC) conditioning might begin to address the transplant-related mortality problems of the older patients. The youngest adults may not need a transplant at all. If they are now treated on pediatric chemotherapy protocols, their outcome appears to improve significantly. The MRC/ECOG study, the emerging MUD and RIC data all help establish allogeneic transplant more widely in this disease.

Where should adolescents with ALL be treated?

Currently, 50% of adolescents with ALL are treated by adult teams and 50% by paediatric teams (following either adult or paediatric protocols). The aim of this paper is to review the results obtained with first-line chemotherapy and with haematopoietic SCT (HSCT) in adolescents with ALL. Disease biology and host factors are responsible for the differences observed between adolescents and other age categories. The outcome of adolescents with ALL after first-line chemotherapy is poorer as compared with children, although better as compared with adults. Recent studies have shown that adolescents who were enrolled in paediatric trials achieved better results than those who were enrolled in adult trials. This is most likely because of several differences, including protocol design, dose intensity and use of HSCTs, as well as better compliance to treatment and better supportive care. Disparities in the attitude towards treatment between paediatric and adult wards might also contribute to the better outcome that is observed in paediatric institutions. Indications for HSCT in children with ALL are well defined by international protocols. Only very high-risk paediatric patients are eligible for HSCT in CR1, whereas in adult trials, allogeneic or autologous HSCT are frequently offered, even to standard-risk patients in CR1. The outcome of adolescents given HSCT is poorer than in children, though better than in adults. Improving both psychosocial support during therapy and physical exercise habits represent further challenges for teams involved in the treatment of adolescents. Cooperation between paediatric and adult haematologists would surely improve the ability to recruit as many patients as possible and would promote progress in the research on adolescents. In conclusion, redefining age limits according to risk-based strategies, as well as encouraging multi-centre cooperation, should be taken into consideration to improve the outcome of this age category. Adolescents should be referred to research treatment teams that have experience in the management of paediatric ALL and they should be enrolled in international cooperative studies.

Survival of European children and young adults with cancer diagnosed 1995-2002

This study analyses survival in 40,392 children (age 0-14 years) and 30,187 adolescents/young adults (age 15-24 years) diagnosed with cancer between 1995 and 2002. The cases were from 83 European population-based cancer registries in 23 countries participating in EUROCARE-4. Five-year survival in countries and in regional groupings of countries was compared for all cancers combined and for major cancers. Survival for 15 rare cancers in children was also analysed. Five-year survival for all cancers combined was 81% in children and 87% in adolescents/young adults. Between-country survival differences narrowed for both children and adolescents/young adults. Relative risk of death reduced significantly, by 8% in children and by 13% in adolescents/young adults, from 1995-1999 to 2000-2002. Survival improved significantly over time for acute lymphoid leukaemia and primitive neuroectodermal tumours in children and for non-Hodgkin lymphoma in adolescents/young adults. Cancer survival in patients <25 years is poorly documented in Eastern European countries. Complete cancer registration should be a priority for these countries as an essential part of a policy for effective cancer control in Europe.

Epidemiology of leukaemia and lymphoma in children and young adults from the north of England, 1990-2002

AIM

We aimed to describe and contrast the epidemiology of haematological malignancies among 0-14 and 15-24-year-olds in northern England from 1990 to 2002 and compare clinical trial entry by age group.

PATIENTS AND METHODS

Incidence rates were examined by age, sex and period of diagnosis and differences were tested using Poisson regression. Differences and trends in survival were assessed using Cox regression.

RESULTS

1680 subjects were included comprising 948 leukaemias and 732 lymphomas. Incidence rates for acute lymphoblastic leukaemia were significantly higher for 0-14 compared to 15-24-year-olds, whilst Hodgkin lymphoma showed the reverse. No significant changes in incidence were observed. 60% of leukaemia patients aged 15-24 years entered trials compared to 92% of 0-14-year-olds. Survival rates were significantly lower and improved less markedly over time for 15-24 compared to 0-14-year-olds, particularly for leukaemia.

CONCLUSIONS

Trial accrual rates need to be improved amongst 15-24-year-olds and a more structured follow-up approach adopted for this unique population.

A systematic review of treatments for constipation in children and young adults undergoing cancer treatment

Constipation is a common problem in children and young people with cancer. Treatment of this complication is subject to wide variation in practice. We undertook a systematic review of randomized controlled trials to build a rational approach to prophylaxis and treatment of this complication. Randomized controlled trials of any intervention (pharmacologic, physical, complementary, or alternative) to prevent or treat constipation were to be included if they included children and young people 16 years old and younger who were undergoing treatment for malignancy. Of the 1336 abstracts retrieved from the searches, only 3 papers were identified for further assessment, and no studies were suitable for inclusion. There are no good data on which to base the management of constipation in children and young people with cancer. This is not to say that we do not know if laxatives work-they are clearly effective. Our ignorance is of the comparative value of different agents. The practical problems with undertaking specific trials of supportive care measures are large, and integration of such questions into treatment trials is essential.

Comparison of the results of the treatment of adolescents and young adults with standard-risk acute lymphoblastic leukemia with the Programa Español de Tratamiento en Hematología pediatric-based protocol ALL-96

PURPOSE

Retrospective studies have shown that adolescents and young adults with acute lymphoblastic leukemia (ALL) treated with pediatric protocols have better outcomes than similarly aged patients treated with adult protocols, but prospective studies comparing adolescents and young adults using pediatric schedules are scarce. The ALL-96 protocol was addressed to compare the toxicity and results of a pediatric-based protocol in adolescents (age 15-18 years) and young adults (age 19-30 years) with standard-risk (SR) ALL.

PATIENTS AND METHODS

Adolescents (n = 35) and young adults (n = 46) received a standard five-drug/5-week induction course followed by two cycles of early consolidation, maintenance with monthly reinforcement cycles up to 1 year in continuous complete remission (CR) and 1 year with standard maintenance chemotherapy up to 2 years in CR.

RESULTS

Adolescents and young adults were comparable in the main pretreatment ALL characteristics. The CR rate was 98% and. after a median follow-up of 4.2 years, 6-year event-free survival (EFS) and overall survival (OS) were 61% (95% CI, 51% to 72%) and 69% (95% CI, 59% to 79%), respectively, with no differences between adolescents and young adults. The hematologic toxicity in consolidation and reinforcement cycles was higher in young adults than in adolescents. Slow response to induction therapy was the only parameter associated with poor EFS (34% v 67%) and OS (40% v 76%).

CONCLUSION

The response to the pediatric ALL-96 protocol was identical in adolescents and young adults despite a slight increase in hematologic toxicity observed in adults. This justifies the age-unrestricted use of pediatric regimens to treat patients with SR ALL.

Microdeletions are a general feature of adult and adolescent acute lymphoblastic leukemia: Unexpected similarities with pediatric disease

We present here a genome-wide map of abnormalities found in diagnostic samples from 45 adults and adolescents with acute lymphoblastic leukemia (ALL). A 500K SNP array analysis uncovered frequent genetic abnormalities, with cryptic deletions constituting half of the detected changes, implying that microdeletions are a characteristic feature of this malignancy. Importantly, the pattern of deletions resembled that recently reported in pediatric ALL, suggesting that adult, adolescent, and childhood cases may be more similar on the genetic level than previously thought. Thus, 70% of the cases displayed deletion of one or more of the CDKN2A, PAX5, IKZF1, ETV6, RB1, and EBF1 genes. Furthermore, several genes not previously implicated in the pathogenesis of ALL were identified as possible recurrent targets of deletion. In total, the SNP array analysis identified 367 genetic abnormalities not corresponding to known copy number polymorphisms, with all but two cases (96%) displaying at least one cryptic change. The resolution level of this SNP array study is the highest used to date to investigate a malignant hematologic disorder. Our findings provide insights into the leukemogenic process and may be clinically important in adult and adolescent ALL. Most importantly, we report that microdeletions of key genes appear to be a common, characteristic feature of ALL that is shared among different clinical, morphological, and cytogenetic subgroups.

The challenges of clinical trials for adolescents and young adults with cancer

In the United States, Europe, and Australia, and probably all countries of the world, older adolescents and young adults with cancer are under-represented in clinical trials of therapies that could improve their outcome. Simultaneously, the survival and mortality rates in these patients have mirrored the clinical trial accrual pattern, with little improvement compared with younger and older patients. This suggests that the relative lack of participation of adolescent and young adult patients in clinical trials has lessened their chances for as good an outcome as that enjoyed by patients in other age groups. Thus, increased availability of and participation in clinical trials is of paramount important if the current deficits in outcome in young adults and older adolescents are to be eliminated. Regardless of whether there is a causal relationship, the impact of low clinical trial activity on furthering our scientific knowledge and management of cancer during adolescence and early adulthood is detrimental.

The distinctive biology of cancer in adolescents and young adults

One explanation for the relative lack of progress in treating cancer in adolescents and young adults is that the biology of malignant diseases in this age group is different than in younger and older persons, not only in the spectrum of cancers but also within individual cancer types and within the patient (host). Molecular, epidemiological and therapeutic outcome comparisons offer clues to this distinctiveness in most of the common cancers of adolescents and young adults. Translational and clinical research should not assume that the biology of cancers and patients is the same as in other age groups, and treatment strategies should be tailored to the differences.

The treatment of adults with acute lymphoblastic leukemia

Despite the relatively low incidence of acute lymphoblastic leukemia (ALL) in adults, large national and international collaborations have recently improved our understanding of how to treat ALL in adults. This article documents and examines the current evidence base for a "state of the art" therapy in both Philadelphia chromosome-negative and -positive adult ALL. The article comments upon areas of therapeutic debate, such as the role of bone marrow transplantation. In particular, the controversial subject of whether the superior outcome seen in younger patients is predicated on disease biology or therapeutic strategy is examined closely. Promising approaches under development are also discussed.

Participation of adolescents with cancer in clinical trials

Adolescent patients with cancer reside in a "no-man's land" between the world of pediatric oncology and that of "adult" medical oncology. As compared to younger and older patients, adolescents and young adults are under-represented on clinical trials. This relative lack of participation in clinical protocols has been associated to a lack of progress in survival improvement over the last years. One of the main reasons for the deficit in protocol enrolment and the worse outcome of adolescents (when compared in particular to children) is the lack of awareness by the public, community and healthcare systems that cancer may occur in this age group. However, physicians--inadequately trained or reluctant to care for adolescents--have important responsibilities. Most 15- to 19-year-olds diagnosed with cancer are treated at adult facilities, although two-thirds to three-fourths of their cancers are typical of those that occur in the pediatric age range. The best choice may be to treat them according to their type of tumor, not according to their age: "pediatric" tumors treated by pediatric oncologists, "adult" tumors by adult medical oncologists, regardless of the patient's age. This solution, however, is probably appropriate for the tumor, but not necessarily for the patient. Adolescents are neither old children nor young adults, and are very complicated individuals, with unique socio-psychological problems and needs, that may be addressed only by dedicated professionals, adequately trained and supported. The ultimate challenge is the development of a new discipline, adolescent/teenage and young adult oncology, devoted to the care of these patients.

Adolescent and young adult (AYA) oncology: the first A

Whereas adolescents with cancer as a group used to have a better prognosis than children with malignant disease, trends suggest that the overall survival of 15- to 19-year-olds is now worse than in younger patients. Also, the incidence of cancer is higher in 15- to 19-year age span than during the first 15 years of life. In 2006, the U.S. National Cancer Institute (NCI) and the Lance Armstrong Foundation conducted a Program Review Group (PRG) of the Adolescent and young Adult (AYA) problem. Recommendations covered awareness, prevention/cancer control/epidemiology/risk, biology, access, health insurance, clinical care models, clinical trials/research, special populations, psychosocial/behavioral factors, health-related quality of life, and long-term effects. This Commentary reviews each of the primary executive recommendations of the PRG report with respect to their adolescent oncology perspective and application. Primary implementation of the recommendations is responsibility of a new consortium of organizations devoted to assisting adolescents and young adults with cancer, the LiveStrong Young Adult Alliance, a program of the Lance Armstrong Foundation. Prior programs included the Children's Oncology Group AYA Committee and two disease-specific initiatives: the Intergroup Consortium Against Sarcoma and a clinical trial in young adults with acute lymphoblastic leukemia that will be conducted by Cancer and Leukemia Group B, the Southwest Oncology Group, and Eastern Cooperative Oncology Group. Preliminary evidence indicates that these efforts have already had measurable success.

Which Patients with Adult Acute Lymphoblastic Leukemia Should Undergo a Hematopoietic Stem Cell Transplantation? Case-Based Discussion

The decision to proceed to transplant for adult patients with acute lymphoblastic leukemia (ALL) is not clear-cut. Relapse and nonrelapse mortality continue to plague the outcome of hematopoietic stem cell transplantation (HSCT) even when undertaken in complete remission (CR). Those considered to be at high risk for relapse often are considered for HSCT in first complete remission (CR1) while those at lower risk may not be referred until they have relapsed, when their chances for cure are very poor. In some patients who have a suitable histocompatible sibling, disease- or patient-related factors may override the potential benefit of allogeneic HSCT. Because many patients do not have a suitable histocompatible sibling, one has to consider the relative merits of autologous transplantation versus use of an alternative allogeneic stem cell source, such as a matched-unrelated donor (MUD), umbilical cord blood (UCB) donor, or haploidentical donor. Deciding among these options in comparison to chemotherapy even in high-risk patients is difficult. In the review, the risks and benefits of these choices are discussed to determine whether and by what means to proceed to HSCT in adult patients with ALL who are in CR1. Presented are two patients with ALL and a discussion of how the data we provide would lead to a decision about the selection of therapy.

Cancer in children and adolescents in Europe: developments over 20 years and future challenges

This special issue contains 18 articles describing population-based analyses of incidence and survival for cancer among children and adolescents in Europe over the period 1978-1997. The analyses were derived from the large database of the ACCIS project (Automated Childhood Cancer Information System), which was built through collaboration of 62 population-based cancer registries in 19 European countries. Data on 88,465 cancers in children and 15,369 in adolescents (age 15-19 yrs) were included in the various analyses, making this the largest database on cancer in these age-groups in the world. National data were grouped into five European regions to allow comparisons of incidence and survival, for all cancers and by tumour type, including analysis of trends in both over time. This overview paper focuses on the comparability of the data from multiple registries and describes the potential confounding factors. Age-standardised annual incidence rates of many, but not all, cancers in children and adolescents are clearly rising. There are geographical differences in survival for the majority of tumour types. Survival rates increased for nearly all types of cancer in children and adolescents. The implications of these findings for aetiological factors and treatment delivery for cancer in children and adolescents are discussed.

Outcome of 609 adults after relapse of acute lymphoblastic leukemia (ALL); an MRC UKALL12/ECOG 2993 study

Most adults with acute lymphoblastic leukemia (ALL) who achieve complete remission (CR) will relapse. We examined the outcome of 609 adults with recurring ALL, all of whom were previously treated on the Medical Research Council (MRC) UKALL12/ECOG2993 study, where the overall survival (OS) of newly diagnosed patients is 38% (95% confidence interval [CI]=36%-41%) at 5 years. By contrast, OS at 5 years after relapse was 7% (95% CI=4%-9%). Factors predicting a good outcome after salvage therapy were young age (OS of 12% in patients younger than 20 years vs OS of 3% in patients older than 50 years; 2P<.001) and short duration of first remission (CR1) (OS of 11% in those with a CR1 of more than 2 years versus OS of 5% in those with a CR1 of less than 2 years; 2P<.001). Treatment received in CR1 did not influence outcome after relapse. In a very highly selected subgroup of patients who were able to receive HSCT after relapse, some were long-term survivors. We conclude from a large, unselected series with mature follow-up that most adults with recurring ALL, whatever their prior treatment, cannot be rescued using currently available therapies. Prevention of recurrence is the best strategy for long-term survival in this disease.

Leukaemia incidence and survival in children and adolescents in Europe during 1978–1997. Report from the Automated Childhood Cancer Information System project

Leukaemias constitute approximately one-third of cancers in children (age 0-14 years) and 10% in adolescents (age 15-19 years). Geographical patterns (1988-1997) and time trends (1978-1997) of incidence and survival from leukaemias in children (n=29,239) and adolescents (n=1929) were derived from the ACCIS database, including data from 62 cancer registries in 19 countries across Europe. The overall incidence rate of leukaemia in children was 44 per million person-years during 1988-1997. Lymphoid leukaemia (LL) accounted for 81%, acute non-lymphocytic leukaemia (ANLL) for 15%, chronic myeloid leukaemia (CML) for 1.5% and unspecified leukaemia for 1.3% of cases. Adjusted for sex and age, incidence of childhood LL was significantly lower in the East and higher in the North than in the British Isles. The overall incidence among adolescents was 22.6 per million person-years. The incidence of LL was rising in children (0.6% per year) and adolescents (1.9% per year). During 1988-1997 5-year survival of children with leukaemias was 73% (95% CI 72-74) and approximately 44% for infants and adolescents. Similar differences in survival between children and adolescents were observed for LL, much less so for ANLL. Survival differed between regions; prognosis was better in the North and West than the East. Remarkable improvements in survival occurred in most of the subgroups of patients defined by diagnostic subgroup, age, sex and geographic categories during the period 1978-1997. For children with ANLL most improvements in survival were observed in the 1990s.

Myths and Lessons from the Adult/Pediatric Interface in Acute Lymphoblastic Leukemia

The development of effective therapy for children with acute lymphoblastic leukemia (ALL) is one of the great successes of clinical oncology, with long-term survival achieved in over 80% of patients. However, cure rates for adults with ALL remain relatively low, with only 40% of patients cured. With an age-unrestricted, biology-based approach, we anticipate a better understanding about why these outcome differences exist, and think that by extending successful pediatric clinical programs to include adult patients with ALL, we can directly compare uniformly treated adults and children in terms of response to therapy, toxicity and underlying biology.