The risk of late effects following pediatric and adult radiotherapy regimens in Hodgkin lymphoma

Consequences of ionizing radiation exposure to the cardiovascular system

Ionizing radiation is widely used in various industrial and medical applications, resulting in increased exposure for certain populations. Lessons from radiation accidents and occupational exposure have highlighted the cardiovascular and cerebrovascular risks associated with radiation exposure. In addition, radiation therapy for cancer has been linked to numerous cardiovascular complications, depending on the distribution of the dose by volume in the heart and other relevant target tissues in the circulatory system. The manifestation of symptoms is influenced by numerous factors, and distinct cardiac complications have previously been observed in different groups of patients with cancer undergoing radiation therapy. However, in contemporary radiation therapy, advances in treatment planning with conformal radiation delivery have markedly reduced the mean heart dose and volume of exposure, and these variables are therefore no longer sole surrogates for predicting the risk of specific types of heart disease. Nevertheless, certain cardiac substructures remain vulnerable to radiation exposure, necessitating close monitoring. In this Review, we provide a comprehensive overview of the consequences of radiation exposure on the cardiovascular system, drawing insights from various cohorts exposed to uniform, whole-body radiation or to partial-body irradiation, and identify potential risk modifiers in the development of radiation-associated cardiovascular disease.

Successful treatment of paediatric refractory Hodgkin lymphoma with immunotherapy - A case report and literature review

AIM

To describe a rare case of primary refractory Hodgkin lymphoma nodular sclerosis syncytial variant in a child and review immunotherapy in relapsed/refractory Hodgkin lymphoma.

METHODS

We described the treatment course of a child with primary refractory classic Hodgkin lymphoma and discussed different options for salvage therapy, with an emphasis on immunotherapy. We searched PubMed for all published clinical trials investigating immunotherapy in classic Hodgkin lymphoma written in English until 31 June, 2023. The reference list of each identified paper was searched for additional publications.

RESULTS

Our patient was salvaged with anti-programmed cell death 1 (PD-1) antibody therapy followed by high-dose chemotherapy with autologous stem cell rescue. Radiotherapy was avoided. We identified five one-armed phase II trials investigating anti-PD-1 therapy in first relapse/refractory disease in a total of 254 patients aged 9-71 years, of which one included 31 children. The complete remission rate before high-dose chemotherapy was 59%-95% overall and 67%-89% among those with refractory disease.

CONCLUSION

Although it remains to be proven in randomised trials, anti-PD-1 therapy may provide higher complete response rates than traditional chemotherapy. Anti-PD-1 therapy has the potential to increase the chance of cure while decreasing the risk of late effects from chemotherapy and radiotherapy.

Total body irradiation as part of conditioning regimens in childhood leukemia-long-term outcome, toxicity, and secondary malignancies

Background

Total body irradiation (TBI) is an established part of conditioning regimens prior to stem cell transplantation in childhood leukemia but is associated with long-term toxicity. We retrospectively analyzed survival, long-term toxicity, and secondary malignancies in a pooled cohort of pediatric patients (pts.) treated with the same TBI regimen.

Methods

Analyzed were 109 pts. treated between September 1996 and November 2015. Conditioning treatment according to EBMT guidelines and the ALL SCTped 2012 FORUM trial consisted of chemotherapy (CT) and TBI with 2 Gy b.i.d. on 3 consecutive days to a total dose of 12 Gy. Median follow-up was 97.9 months (2–228 months).

Results

Overall survival (OS) in our cohort at 2, 5, and 10 years was 86.1, 75.5, and 63.0%, respectively. Median survival was not reached. Long-term toxicity developed in 47 pts. After chronically abnormal liver and kidney parameters in 31 and 7 pts., respectively, growth retardation was the most frequent finding as seen in 13 pts. Secondary malignancies were rare (n = 3).

Conclusion

TBI-containing conditioning regimens in pediatric stem cell transplantation (SCT) are highly effective. Efforts to replace TBI- with CT-containing regimens have only been successful in subgroups of pts. Although we could show long-term toxicity in 43% of pts., overall survival was 63% at 10 years. Still, long-term effects such as growth retardation can permanently impact the pts.’ quality of life and functioning. Along with new substances, efforts should be undertaken to optimize TBI techniques and accompany the treatment by systematic follow-up programs beyond 5 years to improve detection of rare events.

Evaluation of treatment-associated eye toxicity after irradiation in childhood and adolescence-results from the Registry of the Evaluation of Side Effects after Radiotherapy in Childhood and Adolescence (RiSK)

Purpose

The aim of the study is to evaluate treatment-related acute and late eye toxicity associated with radiation therapy in childhood and adolescence as correlated with RT (radiotherapy) doses.

Methods

From 2001 to 2016, a total of 1725 children and adolescents undergoing radiation therapy were prospectively documented in the Registry of the Evaluation of Side Effects after Radiotherapy in Childhood and Adolescence (RiSK). The RTOG/EORTC criteria were used to classify ocular acute and late effects. Uni- and multivariate analyses were carried out to evaluate the impact of patient age, pre-existing impairments, and radiation dose on ocular toxicity.

Results

Of all documented patients, 593 received dose to the eye and formed the basis of this analysis. In 435 patients, information on acute reaction was available and graded 1, 2, 3, and 4 in 49, 17, 0, and 2 patients, respectively. Information on late toxicity was available in 268 patients and graded 1, 2, 3, and 4 in 15, 11, 11, and 5 patients, respectively. The acute toxicity rate was significantly higher in children who received a maximum dose > 50 Gy to the eye (p < 0.001) and who had a pre-existing eye impairment (p < 0.001 in multivariate analysis). The development of late toxicity was significantly higher for patients experiencing acute toxicity and having received a radiation dose > 50 Gy.

Conclusion

Acute and late toxicity both correlate with high radiation dose to the eye (> 50 Gy) and acute toxicity additionally with pre-existing eye impairments.