Development and Validation of a Breast Cancer Risk Prediction Model for Childhood Cancer Survivors Treated With Chest Radiation: A Report From the Childhood Cancer Survivor Study and the Dutch Hodgkin Late Effects and LATER Cohorts

Survivorship after Hodgkin lymphoma and the right to be forgotten

PURPOSE OF REVIEW

The significantly improved survivorship in Hodgkin lymphoma is fraught with challenges, including persistent symptoms, secondary health complications, and socio-professional obstacles. This review highlights the need for comprehensive survivorship care plans that include detection of relapse, assessment of long-term side effects, screening for secondary cancers, psychological support, and assistance with socio-professional integration.

RECENT FINDINGS

Cardiovascular diseases, secondary malignancies and other associated risks remains an important problem related to the effective treatment of patients with Hodgkin lymphoma. Furthermore, fertility concerns and endocrine disorders remain prevalent issues posttreatment. An optimal evaluation of the risks before and after treatment is essential to reduce the impact of these side effects on quality of life. Addressing the socio-professional reintegration of survivors, the concept of the 'Right to be forgotten' emerges as a critical consideration. This principle seeks to eliminate discrimination against cancer survivors in accessing financial services and aims for legislative changes to ensure that past cancer diagnosis does not unfairly affect survivors' futures. Implementation of this 'Right to be forgotten' in the legislature, is currently underway in European countries.

SUMMARY

The focus of survivorship care has shifted towards the holistic management of these long-term outcomes. Quality of life for Hodgkin lymphoma survivors is affected by various treatment-related factors, with evidence suggesting that physical, psychological and socio-professional domains remain impacted years after treatment.

Improving Pediatric Normal Tissue Radiation Dose-Response Modeling in Children With Cancer: A PENTEC Initiative

The development of normal tissue radiation dose-response models for children with cancer has been challenged by many factors, including small sample sizes; the long length of follow-up needed to observe some toxicities; the continuing occurrence of events beyond the time of assessment; the often complex relationship between age at treatment, normal tissue developmental dynamics, and age at assessment; and the need to use retrospective dosimetry. Meta-analyses of published pediatric outcome studies face additional obstacles of incomplete reporting of critical dosimetric, clinical, and statistical information. This report describes general methods used to address some of the pediatric modeling issues. It highlights previous single- and multi-institutional pediatric dose-response studies and summarizes how each PENTEC taskforce addressed the challenges and limitations of the reviewed publications in constructing, when possible, organ-specific dose-effect models.

When Breasts Become a Liability-Discussing Risk-Reducing Mastectomy With Individuals Following Chest Irradiation for Childhood Cancer

This essay describes a woman who had received chest irradiation for childhood cancer and the considerations for and against breast cancer risk–reducing mastectomy.

Improving quality and quantity of life for childhood cancer survivors globally in the twenty-first century

The contributions of cooperative groups to performing large-cohort clinical trials and long-term survivorship studies have facilitated advances in treatment, supportive care and, ultimately, survival for patients with paediatric cancers. As a result, the number of childhood cancer survivors in the USA alone is expected to reach almost 580,000 by 2040. Despite these substantial improvements, childhood cancer survivors continue to have an elevated burden of chronic disease and an excess risk of early death compared with the general population and therefore constitute a large, medically vulnerable population for which delivery of high-quality, personalized care is much needed. Data from large survivorship cohorts have enabled the identification of compelling associations between paediatric cancers, cancer therapy and long-term health conditions. Effectively translating these findings into clinical care that improves the quality and quantity of life for survivors remains an important focus of ongoing research. Continued development of well-designed clinical studies incorporating dissemination and implementation strategies with input from patient advocates and other key stakeholders is crucial to overcoming these gaps. This Review highlights the global progress made and future efforts that will be needed to further increase the quality and quantity of life-years gained for childhood cancer survivors.

Development and Validation of a Prediction Model for Kidney Failure in Long-Term Survivors of Childhood Cancer

PURPOSE

Kidney failure is a rare but serious late effect following treatment for childhood cancer. We developed a model using demographic and treatment characteristics to predict individual risk of kidney failure among 5-year survivors of childhood cancer.

METHODS

Five-year survivors from the Childhood Cancer Survivor Study (CCSS) without history of kidney failure (n = 25,483) were assessed for subsequent kidney failure (ie, dialysis, kidney transplantation, or kidney-related death) by age 40 years. Outcomes were identified by self-report and linkage with the Organ Procurement and Transplantation Network and the National Death Index. A sibling cohort (n = 5,045) served as a comparator. Piecewise exponential models accounting for race/ethnicity, age at diagnosis, nephrectomy, chemotherapy, radiotherapy, congenital genitourinary anomalies, and early-onset hypertension estimated the relationships between potential predictors and kidney failure, using area under the curve (AUC) and concordance (C) statistic to evaluate predictive power. Regression coefficient estimates were converted to integer risk scores. The St Jude Lifetime Cohort Study and the National Wilms Tumor Study served as validation cohorts.

RESULTS

Among CCSS survivors, 204 developed late kidney failure. Prediction models achieved an AUC of 0.65-0.67 and a C-statistic of 0.68-0.69 for kidney failure by age 40 years. Validation cohort AUC and C-statistics were 0.88/0.88 for the St Jude Lifetime Cohort Study (n = 8) and 0.67/0.64 for the National Wilms Tumor Study (n = 91). Risk scores were collapsed to form statistically distinct low- (n = 17,762), moderate- (n = 3,784), and high-risk (n = 716) groups, corresponding to cumulative incidences in CCSS of kidney failure by age 40 years of 0.6% (95% CI, 0.4 to 0.7), 2.1% (95% CI, 1.5 to 2.9), and 7.5% (95% CI, 4.3 to 11.6), respectively, compared with 0.2% (95% CI, 0.1 to 0.5) among siblings.

CONCLUSION

Prediction models accurately identify childhood cancer survivors at low, moderate, and high risk for late kidney failure and may inform screening and interventional strategies.

Premature aging as an accumulation of deficits in young adult survivors of pediatric cancer

BACKGROUND

We aimed to characterize premature aging as an accumulation of deficits in survivors of pediatric cancer compared with community controls and examine associations with host and treatment factors, neurocognition, and mortality.

METHODS

Pediatric cancer survivors (n = 4000, median age = 28.6, interquartile range [IQR] = 23-35 years; 20 years postdiagnosis: IQR = 15-27), and community participants without a history of cancer serving as controls (n = 638, median age = 32, IQR = 25-40 years) completed clinical assessments and questionnaires and were followed for mortality through April 30, 2020 (mean [SD] follow-up = 7.0 [3.4] years). A deficit accumulation index (DAI) score was calculated from 44 aging-related items including self-reported daily function, psychosocial symptoms, and health conditions. Items were weighted from 0 (absent) to 1 (present and/or most severe), summed and divided by the total yielding a ratio (higher = more deficits). Scores less than 0.20 are robust, and 0.06 is a clinically meaningful difference. Linear regression compared the DAI in survivors and controls with an age*survivor or control interaction. Logistic regression and Cox-proportional hazards estimated the risk of neurocognitive impairment and death. Models were minimally adjusted for age, sex, and race and ethnicity.

RESULTS

The adjusted mean DAI among survivors at age 30 years was 0.16 corresponding to age 63 years in controls (33 years premature aging; β = 0.07, 95% confidence interval [CI] = 0.06 to 0.08; P < .001). Cranial and abdominal radiation, alkylators, platinum, and neurosurgery were associated with worse DAI (P ≤ .001). Higher scores were associated with increased risk of neurocognitive impairment in all domains (P < .001) and increased risk of death (DAI = 0.20-0.35, hazard ratio = 2.80, 95% CI = 1.97 to 3.98; DAI ≥ 0.35, hazard ratio = 5.08, 95% CI = 3.52 to 7.34).

CONCLUSION

Pediatric cancer survivors experience clinically significant premature aging. The DAI may be used to identify survivors at greatest risk of poor health outcomes.

Development and Validation of Risk Prediction Models for Coronary Heart Disease and Heart Failure After Treatment for Hodgkin Lymphoma

PURPOSE

Previous efforts to predict absolute risk of treatment-related cardiovascular diseases (CVDs) have mostly focused on childhood cancer survivors. We aimed to develop prediction models for risk of coronary heart disease (CHD) and heart failure (HF) for survivors of adolescent/adult Hodgkin lymphoma (HL).

METHODS

For model development, we used a multicenter cohort including 1,433 5-year HL survivors treated between 1965 and 2000 and age 18-50 years at HL diagnosis, with complete data on administered chemotherapy regimens, radiotherapy volumes and doses, and cardiovascular follow-up. Using cause-specific hazard models, covariate-adjusted cumulative incidences for CHD and HF were estimated in the presence of competing risks of death because of other causes than CHD and HF. Age at HL diagnosis, sex, smoking status, radiotherapy, and anthracycline treatment were included as predictors. External validation for the CHD model was performed using a Canadian cohort of 708 HL survivors treated between 1988 and 2004 and age 18-50 years at HL diagnosis.

RESULTS

After a median follow-up of 24 years, 341 survivors had developed CHD and 102 had HF. We were able to predict CHD and HF risk at 20 and 30 years after treatment with moderate to good overall calibration and moderate discrimination (areas under the curve: 0.68-0.74), which was confirmed by external validation for the CHD model (areas under the curve: 0.73-0.74). On the basis of our model including prescribed mediastinal radiation dose, 30-year risks ranged from 4% to 78% for CHD and 3% to 46% for HF, depending on risk factors.

CONCLUSION

We developed and validated prediction models for CHD and HF with good overall calibration and moderate discrimination. These models can be used to identify HL survivors who might benefit from targeted screening for CVD and early treatment for CVD risk factors.

Questionnaire‐ and linkage‐based outcomes in Dutch childhood cancer survivors: Methodology of the DCCSS LATER study part 1

BACKGROUND

Childhood cancer survivors are at risk for developing long-term adverse health outcomes. To identify the risk of and risk factors for specific health outcomes, well-established cohorts are needed with detailed information on childhood cancer diagnosis, treatment, and health outcomes. We describe the design, methodology, characteristics, and data availability of the Dutch Childhood Cancer Survivor Study LATER cohort (1963-2001) part 1; questionnaire and linkage studies.

METHODS

The LATER cohort includes 5-year childhood cancer survivors, diagnosed in the period 1963-2001, and before the age of 18 in any of the seven former pediatric oncology centers in the Netherlands. Information on health outcomes from survivors and invited siblings of survivors was collected by questionnaires and linkages to medical registries.

RESULTS

In total, 6165 survivors were included in the LATER cohort. Extensive data on diagnosis and treatment have been collected. Information on a variety of health outcomes has been ascertained by the LATER questionnaire study and linkages with several registries for subsequent tumors, health care use, and hospitalizations.

CONCLUSION

Research with data of the LATER cohort will provide new insights into risks of and risk factors for long-term health outcomes. This can enhance risk stratification for childhood cancer survivors and inform surveillance guidelines and development of interventions to prevent (the impact of) long-term adverse health outcomes. The data collected will be a solid baseline foundation for future follow-up studies.

Association of Changes in Cancer Therapy Over 3 Decades With Risk of Subsequent Breast Cancer Among Female Childhood Cancer Survivors: A Report From the Childhood Cancer Survivor Study (CCSS)

Importance

Breast cancer is the most common invasive subsequent malignant disease in childhood cancer survivors, though limited data exist on changes in breast cancer rates as primary cancer treatments have evolved.

Objective

To quantify the association between temporal changes in cancer treatment over 3 decades and subsequent breast cancer risk.

Design, Setting, and Participants

Retrospective cohort study of 5-year cancer survivors diagnosed when younger than 21 years between 1970 and 1999, with follow-up through December 5, 2020.

Exposures

Radiation and chemotherapy dose changes over time.

Main Outcomes and Measures

Breast cancer cumulative incidence rates and age-specific standardized incidence ratios (SIRs) compared across treatment decades (1970-1999). Piecewise exponential models estimated invasive breast cancer and ductal carcinoma in situ (DCIS) risk and associations with treatment exposures, adjusted for age at childhood cancer diagnosis and attained age.

Results

Among 11 550 female survivors (median age, 34.2 years; range 5.6-66.8 years), 489 developed 583 breast cancers: 427 invasive, 156 DCIS. Cumulative incidence was 8.1% (95% CI, 7.3%-9.0%) by age 45 years. An increased breast cancer risk (SIR, 6.6; 95% CI, 6.1-7.2) was observed for survivors compared with the age-sex-calendar-year-matched general population. Changes in therapy by decade included reduced rates of chest (34% in the 1970s, 22% in the 1980s, and 17% in the 1990s) and pelvic radiotherapy (26%, 17%, and 13% respectively) and increased rates of anthracycline chemotherapy exposures (30%, 51%, and 64%, respectively). Adjusting for age and age at diagnosis, the invasive breast cancer rate decreased 18% every 5 years of primary cancer diagnosis era (rate ratio [RR], 0.82; 95% CI, 0.74-0.90). When accounting for chest radiotherapy exposure, the decline attenuated to an 11% decrease every 5 years (RR, 0.89; 95% CI, 0.81-0.99). When additionally adjusted for anthracycline dose and pelvic radiotherapy, the decline every 5 years increased to 14% (RR, 0.86; 95% CI, 0.77-0.96). Although SIRs of DCIS generally increased over time, there were no statistically significant changes in incidence.

Conclusions and Relevance

Invasive breast cancer rates in childhood cancer survivors have declined with time, especially in those younger than 40 years. This appears largely associated with the reduced use of chest radiation therapy, but was tempered by concurrent changes in other therapies.