Risk of hospitalization among survivors of childhood and adolescent acute lymphoblastic leukemia compared to siblings and a general population sample

Manipulating the Gut Microbiome as a Therapeutic Strategy to Mitigate Late Effects in Childhood Cancer Survivors

Recent studies have identified causal links between altered gut microbiome, chronic inflammation, and inflammation-driven conditions such as diabetes and cardiovascular disease. Childhood cancer survivors (CCS) show late effects of therapy in the form of inflammaging-related disorders as well as microbial dysbiosis, supporting a hypothesis that the conditions are interconnected. Given the susceptibility of the gut microbiome to alteration, a number of therapeutic interventions have been investigated for the treatment of inflammatory conditions, though not within the context of cancer survivorship in children and adolescents. Here, we evaluate the potential for these interventions, which include probiotic supplementation, prebiotics/fiber-rich diet, exercise, and fecal microbiota transplantation for prevention and treatment of cancer treatment-related microbial dysbiosis in survivors. We also make recommendations to improve adherence and encourage long-term lifestyle changes for maintenance of healthy gut microbiome in CCS as a potential strategy to mitigate treatment-related late effects.

Long-Term Risk of Hospitalization for Somatic Diseases Among Survivors of Childhood Acute Lymphoblastic Leukemia

Background

Survivors of childhood acute lymphoblastic leukemia (ALL) may be at increased long-term risk of hospitalization for somatic diseases. However, large population-based cohort studies with risk estimates for survivors successfully cured without experiencing a relapse or requiring hematopoietic stem cell transplantation (HSCT) are lacking.

Methods

Danish and Swedish patients diagnosed with ALL before age 20 years in 1982-2008 were identified in the national cancer registries. Five-year survivors and matched population comparisons without childhood cancer were followed for hospitalization for 120 somatic disease categories in the national hospital registries from 5 years postdiagnosis until 2017, and disease-specific hospitalization rate ratios (RR) were calculated. The mean cumulative count method was used to estimate the mean number of multiple and recurrent disease-specific hospitalizations per individual.

Results

A total of 2024 5-year survivors and 9797 population comparisons were included. The overall hospitalization rate was more than twice as high compared with comparisons (RR = 2.30, 95% confidence interval [CI] = 2.09 to 2.52). At 30 years postdiagnosis, the mean cumulative hospitalization count was 1.69 (95% CI = 1.47 to 1.90) per survivor and 0.80 (95% CI = 0.73 to 0.86) per comparison. In the subcohort without relapse or HSCT (n = 1709), the RR was 1.41 (95% CI = 1.27 to 1.58).

Conclusions

Survivors of childhood ALL were at increased long-term risk for disease-specific hospitalizations; however, in survivors without relapse or HSCT, the rate was only modestly higher than in population comparisons without a childhood cancer. The absolute mean numbers of multiple and recurrent hospitalizations were generally low.

Excess morbidity and mortality among survivors of childhood acute lymphoblastic leukaemia: 25 years of follow-up from the United Kingdom Childhood Cancer Study (UKCCS) population-based matched cohort

OBJECTIVES

To examine morbidity and mortality among teenagers and young adults (TYAs) previously diagnosed with acute lymphoblastic leukaemia (ALL) in childhood, and compare to the general TYA population.

DESIGN

National population-based sex-matched and age-matched case-control study converted into a matched cohort, with follow-up linkage to administrative healthcare databases.

SETTING

The study population comprised all children (0-14 years) registered for primary care with the National Health Service (NHS) in England 1992-1996.

PARTICIPANTS

1082 5-year survivors of ALL diagnosed<15 years of age (1992-1996) and 2018 unaffected individuals; followed up to 15 March 2020.

MAIN OUTCOME MEASURES

Associations with hospital activity, cancer and mortality were assessed using incidence rate ratios (IRR) and differences.

RESULTS

Mortality in the 5-year ALL survivor cohort was 20 times higher than in the comparison cohort (rate ratio 21.3, 95% CI 11.2 to 45.6), and cancer incidence 10 times higher (IRR 9.9 95% CI 4.1 to 29.1). Hospital activity was increased for many clinical specialties, the strongest associations being for endocrinology; outpatient IRR 36.7, 95% CI 17.3 to 93.4 and inpatient 19.7, 95% CI 7.9 to 63.2 for males, and 11.0, 95% CI 6.2 to 21.1 and 6.2 95% CI 3.1 to 13.5, respectively, for females. Notable excesses were also evident for cardiology, neurology, ophthalmology, respiratory medicine and general medicine. Males were also more likely to attend gastroenterology; ear, nose and throat; urology; and dermatology, while females were more likely to be seen in plastic surgery and less likely in midwifery.

CONCLUSIONS

Adding to excess risks of death and cancer, survivors of childhood ALL experience excess outpatient and inpatient activity across their TYA years, which is not related to routine follow-up monitoring. Involving most clinical specialties, associations are striking, showing no signs of diminishing over time. Recognising that all survivors are potentially at risk of late treatment-associated effects, our findings underscore the need to take prior ALL diagnosis into account when interpreting seemingly unrelated symptoms later in life.

Matched cohort study of hospitalization in children who have siblings with cancer

BACKGROUND

Health outcomes of children in families affected by cancer are poorly understood. The authors assessed the risk of hospitalization in children who have a sibling with cancer.

METHODS

This was a longitudinal cohort study in which 1600 children who had a sibling with cancer were matched to 32,000 children who had unaffected siblings in Quebec, Canada, from 2006 to 2020. The exposure of interest was having a sibling with cancer. Outcomes included hospitalization for pneumonia, asthma, fracture, and other morbidities any time after the sibling was diagnosed with cancer. The children were followed over time, and Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the impact of having a sibling with cancer on the risk of hospitalization before age 14 years, adjusted for patient characteristics.

RESULTS

Children who had a sibling with cancer had an increased risk of hospitalization compared with unaffected children (HR, 1.15; 95% CI, 1.02-1.29). Conditions associated with a greater risk of hospitalization included pneumonia, hemangioma, other skin conditions, sleep apnea, and inflammatory bowel disease. The risk of hospitalization was greatest for children whose older sibling had cancer (HR, 1.16; 95% CI, 1.01-1.32) and for children whose sibling had hematopoietic cancer (HR, 1.22; 95% CI, 1.01-1.48).

CONCLUSIONS

Children who have a sibling with cancer are at risk of hospitalization for conditions such as pneumonia, inflammatory bowel disease, and other morbidities. Families affected by childhood cancer may benefit from additional support to facilitate care for all children in the family.

LAY SUMMARY

Little is known about the health of children who have a brother or sister with cancer. The authors studied the types of hospitalization experienced by children who have siblings with cancer. The results indicated that having a sibling with cancer increased the chance of being hospitalized for pneumonia and other conditions that could have been preventable. The results also indicated that children who had an older sibling with cancer or a sibling with blood cancer had a greater chance of being hospitalized. The findings highlight the importance of providing timely care for children in families affected by childhood cancer.

Vincristine-Induced Peripheral Neuropathy in Childhood Acute Lymphoblastic Leukemia: Genetic Variation as a Potential Risk Factor

Vincristine (VCR) is the first-line chemotherapeutic medication often co-administered with other drugs to treat childhood acute lymphoblastic leukemia. Dose-dependent neurotoxicity is the main factor restricting VCR’s clinical application. VCR-induced peripheral neuropathy (VIPN) sometimes results in dose reduction or omission, leading to clinical complications or affecting the patient’s quality of life. With regard to the genetic basis of drug responses, preemptive pharmacogenomic testing and simultaneous blood level monitoring could be helpful for the transformation of various findings into individualized therapies. In this review, we discussed the potential associations between genetic variants in genes contributing to the pharmacokinetics/pharmacodynamics of VCR and VIPN incidence and severity in patients with acute lymphoblastic leukemia. Of note, genetic variants in the CEP72 gene have great potential to be translated into clinical practice. Such a genetic biomarker may help clinicians diagnose VIPN earlier. Besides, genetic variants in other genes, such as CYP3A5, ABCB1, ABCC1, ABCC2, TTPA, ACTG1, CAPG, SYNE2, SLC5A7, COCH, and MRPL47, have been reported to be associated with the VIPN, but more evidence is needed to validate the findings in the future. In fact, a variety of complex factors jointly determine the VIPN. In implementing precision medicine, the combination of genetic, environmental, and personal variables, along with therapeutic drug monitoring, will allow for a better understanding of the mechanisms of VIPN, improving the effectiveness of VCR treatment, reducing adverse reactions, and improving patients’ quality of life.

Health care utilisation following childhood acute lymphoblastic leukaemia: a population-based matched cohort study

OBJECTIVES

Survival among children diagnosed with acute lymphoblastic leukaemia (ALL) has increased considerably. However, morbidity in survivors constitutes a potential increasing burden not limited to secondary health care. Our objectives were to compare health care utilisation, including both primary and secondary health care, between childhood ALL survivors and matched references up to 15 years after curative treatment. Moreover, to increase knowledge on survivors' health service seeking behaviour as time from treatment elapsed.

DESIGN AND SETTING

A Danish population-based matched cohort study linking multiple nationwide registries.

PARTICIPANTS

675 cases, diagnosed with childhood (1.0-17.9 years) ALL between 1994 and 2015, and 6750 matched references sampled randomly from the source population (matched on age, gender and geographical region).

PRIMARY OUTCOME MEASURES

Repeated consultations in general practice and hospital (outpatient and inpatient) estimated as yearly rates from 2.5 years after diagnosis and onwards. We compared cases and references with yearly incidence rate ratios (IRRs) from negative binomial regression models.

RESULTS

Survivors of childhood ALL had a mean number of yearly daytime contacts in general practice of 4.75 (95% CI 4.41 to 5.11) the first year, corresponding to an IRR of 1.85 (95% CI 1.71 to 2.00); decreasing to 1.16 (1.01 to 1.34) after 15 years, and without significant impact of gender (p=0.894) or age (p=0.399). For hospital contacts, ALL survivors had a mean number of yearly contacts of 14.21 (13.38-15.08) the first year, corresponding to an IRR of 31.50 (28.29-35.07); decreasing to 2.42 (1.59-3.68) after 15 years. No differences were found across calendar time.

CONCLUSIONS

ALL survivors used significantly more health care services across sectors than the reference population. Decreasing use over 15 years illustrated the dynamics of health care needs; this knowledge may inform the future organisation of integrated follow-up programmes.

TRIAL REGISTRATION NUMBER

NCT03985826.

Phase-specific risks of outpatient visits, emergency visits, and hospitalizations during Children's Oncology Group-based treatment for childhood acute lymphoblastic leukemia: A population-based study

BACKGROUND

Therapy for childhood acute lymphoblastic leukemia (ALL) is associated with substantial health care utilization and burden on families. Little is known about health care utilization during specific treatment phases.

PROCEDURES

We identified children with ALL diagnosed during 2002-2012 in Ontario, Canada and treated according to Children's Oncology Group (COG) protocols. Disease and treatment data were chart abstracted. Population-based health care databases identified all outpatient visits, emergency department (ED) visits, and hospitalizations. In addition to comparing standard and intensified versions of treatment phases, we compared patients receiving different steroids (dexamethasone vs. prednisone) and different versions of interim maintenance (IM) (Capizzi vs. high-dose methotrexate [HD-MTX]).

RESULTS

Six hundred thirty-seven children met inclusion criteria. During intensified consolidation, 76.2% of patients were hospitalized at least once, compared to only 32.3% of patients receiving standard consolidation (p < .0001). Similarly, 72.9% of patients receiving intensified delayed intensification (DI) were hospitalized during this phase compared to 50.3% of patients receiving standard DI (p < .0001). Among patients receiving a four-drug induction, those receiving dexamethasone had an 85% higher rate of ED visits (adjusted rate ratio [aRR] 1.85, 95th confidence interval [95CI] 1.14-3.00; p = .01) and a 44% higher rate of hospitalization (aRR 1.44, 95CI 1.24-1.68) compared to those receiving prednisone. Among high-risk B-ALL and T-ALL patients in IM, Capizzi MTX was not associated with an increased rate of ED visits versus HD-MTX.

CONCLUSIONS

These results can be used to inform anticipatory guidance for families, particularly those undergoing intensified therapy. Our results also suggest that increased toxicity rates associated with dexamethasone during Induction seen in clinical trials reflect real-world practice.

Long-Term Risk of Hospitalization Among Five-Year Survivors of Childhood Leukemia in the Nordic Countries

BACKGROUND

Adverse effects from childhood leukemia treatment may persist or present years after cure from cancer. We provide a comprehensive evaluation of subsequent hospitalization in five-year survivors of childhood acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), and chronic myeloid leukemia (CML).

METHODS

In the Adult Life after Childhood Cancer in Scandinavia Study, we identified 4003 five-year survivors diagnosed with childhood leukemia 1970-2008 in Denmark, Sweden, Iceland, and Finland. Survivors and 129 828 population comparisons were followed for first-time nonpsychiatric hospitalizations for 120 disease categories in the hospital registries. Standardized hospitalization rate ratios and absolute excess rates were calculated. All statistical tests were two-sided.

RESULTS

Survivors of ALL (n = 3391), AML (n = 389), and CML (n = 92) had an increased overall hospitalization rate compared with population comparisons. The rate ratio for any hospitalization was 1.95 (95% confidence interval [CI] = 1.83 to 2.07) in ALL, 3.09 (95% CI = 2.53 to 3.65) in AML, and 4.51 (95% CI = 3.03 to 6.00) in CML survivors and remained increased even 20 years from leukemia diagnosis. Corresponding absolute excess rates per 1000 person-years were 28.48 (95% CI = 24.96 to 32.00), 62.75 (95% CI = 46.00 to 79.50), and 105.31 (95% CI = 60.90 to 149.72).

CONCLUSION

Leukemia survivors have an increased rate of hospitalization for medical conditions. We provide novel insight into the relative and absolute rate of hospitalization for 120 disease categories in survivors of ALL, AML, and CML, which are likely to be informative for both survivors and healthcare providers.

Fine Particulate Matter and Respiratory Healthcare Encounters among Survivors of Childhood Cancers

Some chemotherapies that treat childhood cancers have pulmonary-toxic properties that increase risk for adverse respiratory-health outcomes. PM_2.5 causes similar outcomes but its effect among pulmonary compromised cancer survivors is unknown. This case-crossover study identified the PM_2.5-associated odds for primary-respiratory hospitalizations and emergency department visits among childhood cancer survivors in Utah. We compared risk among chemotherapy-treated survivors to a cancer-free sample. We calculated 3-day-average PM_2.5 by ZIP code and county for event and control days. Conditional logistic regression estimated odds ratios. Models were stratified by cause of admission (infection, respiratory disease, asthma), previous chemotherapy, National Ambient Air Quality Standard (NAAQS), and other variables. Results are presented per 10 µg/m³ of PM_2.5. 90% of events occurred at 3-day PM_2.5 averages <35.4 µg/m³, the NAAQS 24-h standard. For survivors, PM_2.5 was associated with respiratory hospitalizations (OR = 1.84, 95% CI = 1.13⁻3.00) and hospitalizations from respiratory infection (OR = 2.09, 95% CI = 1.06⁻4.14). Among chemotherapy-treated survivors, the PM_2.5-associated odds of respiratory hospitalization (OR = 2.03, 95% CI = 1.14⁻3.61) were significantly higher than the cancer-free sample (OR = 0.84, 95% CI = 0.57⁻1.25). This is the first study to report significant associations between PM_2.5 and respiratory healthcare encounters in childhood cancer survivors. Chemotherapy-treated survivors displayed the highest odds of hospitalization due to PM_2.5 exposure and their risk is significantly higher than a cancer-free sample.

Genetic Variants Associated With Vincristine-Induced Peripheral Neuropathy in Two Populations of Children With Acute Lymphoblastic Leukemia

Vincristine is one of the core chemotherapy agents used in the treatment of pediatric acute lymphoblastic leukemia (ALL). However, one of the major toxicities resulting from vincristine exposure is vincristine-induced peripheral neuropathy (VIPN). When VIPN results in significant morbidity, the vincristine dose may need to be reduced, thus potentially decreasing the effectiveness of treatment. To date, there are no robust biomarkers used clinically to determine which patients will be at risk for worse neuropathy. The current study included genomewide association study (GWAS) in two independent cohorts: Pediatric Oncology Group (POG) ALL trials and a multicenter study based at Indiana University in children with ALL. A meta-analysis of the cohorts identified two single-nucleotide polymorphisms (SNPs), rs1045644 and rs7963521, as being significantly (P value threshold 0.05/4749 = 1.05E-05) associated with neuropathy. Subsequently these SNPs may be effective biomarkers of VIPN in children with ALL.