Cardiac-Sparing Whole Lung Intensity Modulated Radiation Therapy in Children With Wilms Tumor: Final Report on Technique and Abdominal Field Matching to Maximize Normal Tissue Protection

Dosimetric Advantage of Combined IMRT for Whole Lung and Abdomen Irradiation for Wilms Tumor

Purpose

In patients with Wilms tumor with lung metastases, a cardiac-sparing intensity modulated radiation therapy (CS-IMRT) technique is increasingly being adopted for whole lung irradiation. However, the standard technique for flank and whole abdomen radiation remains 2-dimensional anterioposterior (AP), and overlap at the junction between the whole lung CS-IMRT and abdominal AP fields can result in overdose to normal organs. Here, we compared the dosimetry of patients who received whole lung irradiation and flank or abdominal radiation therapy with CS-IMRT with AP abdominal field (IMRT-AP) versus CS-IMRT with IMRT abdominal field (combined IMRT).

Methods and Materials

We retrospectively reviewed the radiation plans of 2 patients with Wilms tumor who received CS-IMRT and flank or whole abdomen irradiation with a combined IMRT approach. Comparison IMRT-AP plans were generated with equivalent target coverage of 95% receiving the prescribed dose. Maximum doses to normal organs were compared at the junctional overlap.

Results

Overlap at the junction between CS-IMRT and abdominal fields resulted in a significantly lower dose with combined IMRT plans compared with IMRT-AP plan. Differences in maximum doses (in cGy) to normal organs between combined IMRT versus IMRT-AP plans were most significant in the vertebral body (patient 1 = 1277 vs 2065; patient 2 = 1334 vs 2287), lungs (patient 1 = 1298 vs 2081; patient 2 = 1234 vs 1820), spinal cord (patient 1 = 1235 vs 1975; patient 2 = 1345 vs 2253), stomach (patient 1 = 1264 vs 1977; patient 2 = 1118 vs 2062), and liver (patient 1 = 1297 vs 1889; patient 2 = 1334 vs 2237).

Conclusions

The combined IMRT approach for Wilms patients who require whole lung and abdomen irradiation can provide more uniform dose distribution in the junction area and significantly lower doses to normal organs at the junctional overlap.

Long-Term Outcomes After Abdominal Radiation for Wilms Tumor: A 20-Year Experience

BACKGROUND

As radiation therapy (RT) for Wilms tumor (WT) evolves with more conformal techniques, it is necessary to evaluate patterns of failure and toxicity. We sought to determine the rate of local failure (LF) after abdominal RT in WT, specifically focusing on those with contained rupture treated with whole abdominal and pelvic RT (WAPRT) vs flank RT. Secondary objectives were to determine overall survival (OS), distant failure (DF), and late toxicities.

METHODS

A single institution retrospective study of 54 pediatric patients with WT treated with abdominal RT between May 2000 and October 2022. LF and DF were calculated through cumulative incidence function and OS by Kaplan-Meier method.

RESULTS

The median age was 4.5 years and the median follow-up was 6 years. Most patients (91%) had favorable histology. Only 1 patient experienced LF, 15 months from completion of RT (cumulative incidence 2% at 5 y). All patients who received unilateral flank radiation for contained rupture/spillage (n=13) experienced long-lasting intra-abdominal tumor control. A total of 5 patients experienced a DF at a median of 7 months, all in the lung. No patient relapsed in the lungs after upfront whole lung irradiation (n=16). OS was 96% at 5 years. Among 28 patients who followed through puberty, 4 female patients with prior WAPRT experienced hormonal irregularities/infertility.

CONCLUSIONS

Unilateral flank radiation may be a viable alternative to WAPRT for contained rupture/spillage and should be further explored prospectively. Our results may also be utilized in the future for outcome and toxicity comparison as conformal radiation techniques evolve.

Cardiovascular Health Status And Genetic Risk In Survivors of Childhood Neuroblastoma and Nephroblastoma Treated With Doxorubicin: Protocol of the Pharmacogenetic Part of the LESS-Anthra Cross-Sectional Cohort Study

BACKGROUND

In childhood cancer survivors (survival of 5 years or more after diagnosis), cardiac toxicity is the most common nonmalignant cause of death attributed to treatment-related consequences. Identifying patients at risk of developing late cardiac toxicity is therefore crucial to improving treatment outcomes. The use of genetic markers has been proposed, together with clinical risk factors, to predict individual risk of cardiac toxicity from cancer therapies, such as doxorubicin.

OBJECTIVE

The primary aim of this study is to evaluate the value of multimarker genetic testing for RARG rs2229774, UGT1A6 rs17863783, and SLC28A3 rs7853758 for predicting doxorubicin-induced cardiotoxicity. The secondary aim is to replicate previously described associations of candidate genetic markers with doxorubicin-induced cardiotoxicity. Moreover, we will evaluate the prevalence of cardiovascular dysfunction in childhood cancer survivors after neuroblastoma or nephroblastoma.

METHODS

This is the pharmacogenetic substudy of the research project Structural Optimization for Children With Cancer After Anthracycline Therapy (LESS-Anthra). We invited 2158 survivors of childhood neuroblastoma or nephroblastoma treated with doxorubicin according to the trial protocols of SIOP 9/GPOH, SIOP 93-01/GPOH, SIOP 2001/GPOH, NB 90, NB 97, or NB 2004 to participate in this prospective cross-sectional cohort study. The study participants underwent a cardiological examination and were asked to provide a blood or saliva sample for genotyping. The study participants' health statuses and cardiovascular diagnoses were recorded using a questionnaire completed by the cardiologist. Digital echocardiographic data were centrally evaluated to determine the contractile function parameters. Medical data on the tumor diagnosis and treatment protocol were taken from the study documentation. Survivors were screened for variants of several candidate genes by TaqMan genotyping.

RESULTS

This study includes 657 survivors treated with doxorubicin for childhood cancer, the largest German cohort assembled to date to investigate cardiovascular late effects. Data analyses are yet to be completed.

CONCLUSIONS

This study will define the genetic risk related to 3 marker genes proposed in a pharmacogenetic guideline for risk assessment. Moreover, the results of this study will show the prevalence of cardiovascular dysfunction in survivors of pediatric neuroblastoma or nephroblastoma who were treated with doxorubicin. The results will help to improve primary treatment and follow-up care, thus reducing cardiovascular late effects in the growing population of childhood cancer survivors.

TRIAL REGISTRATION

German Clinical Trials Register DRKS00015084; https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00015084.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/27898.

Multidisciplinary Treatment Strategies for Wilms Tumor: Recent Advances, Technical Innovations and Future Directions

Significant progress has been made in the management of Wilms tumor (WT) in recent years, mostly as a result of collaborative efforts and the implementation of protocol-driven, multimodal therapy. This article offers a comprehensive overview of current multidisciplinary treatment strategies for WT, whilst also addressing recent technical innovations including nephron-sparing surgery (NSS) and minimally invasive approaches. In addition, surgical concepts for the treatment of metastatic disease, advances in tumor imaging technology and potentially prognostic biomarkers will be discussed. Current evidence suggests that, in experienced hands and selected cases, laparoscopic radical nephrectomy and laparoscopic-assisted partial nephrectomy for WT may offer the same outcome as the traditional open approach. While NSS is the standard procedure for bilateral WT, NSS has evolved as an alternative technique in patients with smaller unilateral WT and in cases with imminent renal failure. Metastatic disease of the lung or liver that is associated with WT is preferably treated with a three-drug chemotherapy and local radiation therapy. However, surgical sampling of lung nodules may be advisable in persistent nodules before whole lung irradiation is commenced. Several tumor markers such as loss of heterozygosity of chromosomes 1p/16q, 11p15 and gain of function at 1q are associated with an increased risk of recurrence or a decreased risk of overall survival in patients with WT. In summary, complete resection with tumor-free margins remains the primary surgical aim in WT, while NSS and minimally invasive approaches are only suitable in a subset of patients with smaller WT and low-risk disease. In the future, advances in tumor imaging technology may assist the surgeon in defining surgical resection margins and additional biomarkers may emerge as targets for development of new diagnostic tests and potential therapies.

Wilms tumour

Wilms tumour (WT) is a childhood embryonal tumour that is paradigmatic of the intersection between disrupted organogenesis and tumorigenesis. Many WT genes play a critical (non-redundant) role in early nephrogenesis. Improving patient outcomes requires advances in understanding and targeting of the multiple genes and cellular control pathways now identified as active in WT development. Decades of clinical and basic research have helped to gradually optimize clinical care. Curative therapy is achievable in 90% of affected children, even those with disseminated disease, yet survival disparities within and between countries exist and deserve commitment to change. Updated epidemiological studies have also provided novel insights into global incidence variations. Introduction of biology-driven approaches to risk stratification and new drug development has been slower in WT than in other childhood tumours. Current prognostic classification for children with WT is grounded in clinical and pathological findings and in dedicated protocols on molecular alterations. Treatment includes conventional cytotoxic chemotherapy and surgery, and radiation therapy in some cases. Advanced imaging to capture tumour composition, optimizing irradiation techniques to reduce target volumes, and evaluation of newer surgical procedures are key areas for future research.

Wilms Tumor (Nephroblastoma), Version 2.2021, NCCN Clinical Practice Guidelines in Oncology

The NCCN Guidelines for Wilms Tumor focus on the screening, diagnosis, staging, treatment, and management of Wilms tumor (WT, also known as nephroblastoma). WT is the most common primary renal tumor in children. Five-year survival is more than 90% for children with all stages of favorable histology WT who receive appropriate treatment. All patients with WT should be managed by a multidisciplinary team with experience in managing renal tumors; consulting a pediatric oncologist is strongly encouraged. Treatment of WT includes surgery, neoadjuvant or adjuvant chemotherapy, and radiation therapy (RT) if needed. Careful use of available therapies is necessary to maximize cure and minimize long-term toxicities. This article discusses the NCCN Guidelines recommendations for favorable histology WT.

New aspects and innovations in the local treatment of renal and urogenital pediatric tumors

Local treatment plays a key role for patients' outcome in tumors of the urogenital tract in children. Despite a great variety of different etiologies, the specific localization of pediatric urogenital tumors renders several characteristic demands to the treating personnel. Surgery and radiotherapy are the main elements of local treatment in this group of neoplasms. Numerous new guidelines and innovative technical developments of surgery and radiotherapy have recently been integrated into treatment concepts for pediatric urogenital tumors. Due to the broadness of the field it is not possible to give a full overview over all aspects. Therefore, this article highlights the most important innovations and new guidelines of surgery and radiotherapy of pediatric urogenital tumors.

Low-dose radiotherapy for COVID-19 pneumonia treatment: case report, procedure, and literature review

BACKGROUND

The COVID-19 pandemic outbreak has set the emergency services in developing countries on major alert, as the installed response capacities are easily overwhelmed by the constantly increasing high demand. The deficit of intensive care unit beds and ventilators in countries like Peru is forcing practitioners to seek preventive or early interventional strategies to prevent saturating these chronically neglected facilities.

CASE PRESENTATION

A 64-year-old patient is reported after presenting with COVID-19 pneumonia and rapidly progressing to deteriorated ventilatory function. Compassionate treatment with a single 1‑Gy dose to the bilateral whole-lung volume was administered, with gradual daily improvement of ventilatory function and decrease in serum inflammatory markers and oxygen support needs, including intubation. No treatment-related toxicity developed. Procedures of transport, disinfection, and treatment planning and delivery are described.

CONCLUSION

Whole-lung low-dose radiotherapy seems to be a promising approach for avoiding or delaying invasive respiratory support. Delivered low doses are far from meeting toxicity ranges. On-going prospective trials will elucidate the effectiveness of this approach.

Kidney-sparing whole abdominal irradiation in Wilms tumor: Potential advantages of VMAT technique

PURPOSE

To present a preliminary clinical experience and a dosimetric comparison of kidney-sparing volumetric modulated arc therapy (VMAT) with three-dimensional conformal radiotherapy (3D-CRT) for whole abdominal irradiation (WAI), in the setting of Wilms tumor (WT) treatment.

MATERIALS AND METHODS

From a total of 20 consecutive WT cases treated with adjuvant irradiation, seven were submitted to WAI with VMAT. Renal function and survival rates were evaluated, and, for comparison purposes, similar VMAT and 3D-CRT treatment plans were performed for WAI patients, and differences were dosimetrically evaluated regarding doses to the remaining kidney and other organs at risk and the planning target volume (PTV).

RESULTS

After a median follow-up time of 40.8 months (35.3-52.2), no acute significant intestinal toxicity was observed, and median creatinine clearance was 110.1 and 103.3 mL/min/1.73 m², respectively, before treatment and at last follow-up for WAI patients (P = 0.128). For comparative plans, maximum and median doses were lower for the remaining kidney with VMAT than with 3D-CRT. VMAT was associated with better PTV coverage as compared with 3D-CRT, with superior results for all the evaluated parameters (D95, D2, V100%, V98%, V95%; P = 0.018).

CONCLUSION

The use of VMAT technique is associated with lower radiation doses to the remaining kidney and better coverage to the PTV than 3D-CRT technique for WAI, with preliminary clinical experience showing a favorable toxicity profile. Long-term results from prospective studies might prove the ability of VMAT to spare renal function in the setting of WT treatment.