Fatal radiation myelopathy after high-dose busulfan and melphalan chemotherapy and radiotherapy for Ewing's sarcoma: a review of the literature and implications for practice

Predictive Factors Associated With Radiation Myelopathy in Pediatric Patients With Cancer: A PENTEC Comprehensive Review

PURPOSE

Radiation myelitis (RM) is a rare complication of radiation therapy (RT). The Pediatric Normal Tissue Effects in the Clinic spinal cord task force aimed to identify RT dose effects and assess risk factors for RM in children. Through systematic review, we analyzed RT dose, fraction size, latency between completion of RT and toxicity, chemotherapy use, age when irradiated, and sex.

METHODS AND MATERIALS

We conducted literature searches of peer-reviewed manuscripts published from 1964 to June 2017 evaluating RM among children. Normality of variables was assessed with Kolmogorov-Smirnov or Shapiro-Wilk tests. Spearman's rank correlation coefficients were used to test correlations between RT dose/fraction size and latency between RT and development of toxicity.

RESULTS

Of 1329 identified and screened reports, 144 reports were fully reviewed and determined to have adequate data for analysis; 16 of these reports had a total of 33 cases of RM with a median age of 13 years (range, 0.2-18) at the time of RT. The most common primary tumor histologies were rhabdomyosarcoma (n = 9), medulloblastoma (n = 5), and Hodgkin lymphoma (n = 2); the most common chemotherapy agents given were vincristine (n = 15), intrathecal methotrexate (n = 12), and intrathecal cytarabine (n = 10). The median RT dose and fraction size were 40 Gy (range, 24-57.4 Gy) and 1.8 Gy (range, 1.3-2.6 Gy), respectively. RT dose resulting in RM in patients who also received chemotherapy was lower than in those not receiving chemotherapy (mean 39.6 vs 49.7 Gy; P = .04). There was no association of age with RT dose. The median latency period was 7 months (range, 1-29). Higher RT dose was correlated with longer latency periods (P = .03) to RM whereas sex, age, fraction size, and chemotherapy use were not. Two of 17 patients with adequate follow-up recovered from RM; unfortunately, it was fatal in 6 of 15 evaluable patients. Complication probability modeling was not possible because of the rarity of events.

CONCLUSIONS

This report demonstrates a relatively short latency from RT (with or without chemotherapy) to RM and a wide range of doses (including fraction sizes) associated with RM. No apparent association with age at the time of RT could be discerned. Chemotherapy appears to reduce spinal cord tolerance. Recovery from RM is rare, and it is often fatal.

Stereotactic Body Radiation Therapy for Spinal Metastases: Benefits and Limitations

Progress in biological cancer characterization, targeted systemic therapies and multimodality treatment strategies have shifted the goals of radiotherapy for spinal metastases from short-term palliation to long-term symptom control and prevention of compilations. This article gives an overview of the spine stereotactic body radiotherapy (SBRT) methodology and clinical results of SBRT in cancer patients with painful vertebral metastases, metastatic spinal cord compression, oligometastatic disease and in a reirradiation situation. Outcomes after dose-intensified SBRT are compared with results of conventional radiotherapy and patient selection criteria will be discussed. Though rates of severe toxicity after spinal SBRT are low, strategies to minimize the risk of vertebral compression fracture, radiation induced myelopathy, plexopathy and myositis are summarized, to optimize the use of SBRT in multidisciplinary management of vertebral metastases.

Overcoming inter-observer planning variability in target volume contouring and dose planning for high-risk neuroblastoma - a European multicenter effort of the SIOPEN radiotherapy committee

BACKGROUND AND PURPOSE

To establish an international quality standard for contouring and planning for high-risk neuroblastoma within the prospective High-Risk Neuroblastoma Study 2 of SIOP-Europe-Neuroblastoma (SIOPEN HR-NBL2), which includes a randomized question on dose escalation for residual disease.

MATERIALS AND METHODS

Data on four patients with high-risk neuroblastoma were selected and distributed to the radiotherapy committee of the HR-NBL2 study for independent contouring and planning. Differences in contouring were analyzed using apparent and kappa-corrected agreement. Plans were analyzed regarding the dose-volume histogram metrics. Results were discussed among experts and agreement was obtained.

RESULTS

Substantial agreement was found for contouring of the heart (0.64), liver (0.70), left lung (0.74), and right lung (0.74). For contouring of the gastrointestinal tract (0.54), left kidney (0.60), and right kidney (0.59) moderate agreement was obtained. For target volume delineation, agreement for preoperative tumour extent was moderate (0.42), for CTV fair (0.35) and only low (0.06) for residual tumour, respectively. The dose planning strategies appeared to be relatively homogeneous among all experts.

CONCLUSION

Considerable variability was found for the delineation of target volumes, particularly the boost volume, whereas the contouring of the organs at risk and the planning strategy were reasonably consistent. In order to obtain reliable results from the randomized HR-NBL2 trial, standardization of target volume delineation based on adequate imaging is crucial.

High-dose chemotherapy followed by whole lung irradiation in pulmonary relapse Ewing’s sarcomas: a retrospective multicenter study

Objective:

Regarding the efficiency of Bu-Mel-based high-dose-chemotherapy (Bu-Mel-HDCT) and whole lung irradiation (WLI), the objective was to evaluate the efficiency and safety of this salvage sequence in Ewing sarcoma (ES) lung relapses.

Methods:

All eligible pediatric ES patients (1991–2020) identified in SFCE departments were retrospectively reviewed. Seven patients were (1) diagnosed with a pulmonary relapse, isolated or not, (2) naïve from both HCDT and WLI (3) treated by the salvage sequence of conventional chemotherapy, Bu-Mel-HDCT and WLI. The main endpoint was OS evaluation. WLI toxicities were scored using CTC-V5.

Results:

With a 13 years median follow-up (FU), 5/7 patients are alive and in complete remission. 10y-EFS is 71.4%. Three patients experienced transitory radio-induced pneumopathy (RIP). A patient developed RIP (gr.3) and finally progressive lung fibrosis leading to death.

Conclusion:

This study reports seven ES patients treated for lung metastatic relapses, using an aggressive strategy, with favorable survival long-term results which should be balanced with the risk of lung toxicity.

Advances in knowledge:

The approach of surgery, Bu-Mel HDCT followed by WLI can be discussed in selected ES patients with lung relapse, naive from HDCT or WLI, providing an optimal chemosensitivity. A special vigilance is necessary regarding the incidence rate of lung toxicity which can be mitigated by limiting the radiotherapy dose, and observing optimal timing of radiotherapy after HDCT.

Successful treatment of quadriparesis from radiation myelopathy with bevacizumab in a patient with metastatic breast cancer

Radiation myelopathy (RM) is rare condition defined as injury to the spinal cord by ionising radiation. Due to improved survival in patients with advanced malignancies, there is a renewed interest in recognition and treatment of RM. There are very few reports on treatment of RM. A 64-year-old woman with metastatic oestrogen receptor, progesterone receptor weakly positive and human epidermal growth factor 2 negative breast, stereotactic radiosurgeries to brain metastases and a history of reradiation to the cervical spinal cord presented with neck pain, arm weakness, hyperreflexia and gait ataxia. RM was suspected and the patient was started on high dose corticosteroid therapy. However, the patient's condition deteriorated and she developed quadriparesis. A timely treatment with an antivascular endothelial growth factor antibody, bevacizumab reversed her neurological deficits and preserved her walking ability. Our case illustrates a prompt diagnosis and successful treatment of RM with bevacizumab.

Ewing sarcoma

Ewing sarcoma is a rare tumor that requires complex multidisciplinary management. This report describes the general management and standard radiotherapy guidelines in both North America (Children's Oncology Group) and Europe (International Society of Pediatric Oncology). Standard treatment involves multiagent induction chemotherapy followed by local treatment with surgery, definitive radiation, or a combination of surgery and radiation followed by additional chemotherapy and consolidation local treatment to metastatic sites. The data supporting the role of chemotherapy, surgery, and radiation and specific radiation therapy guidelines are presented.

Ewing Sarcoma-Diagnosis, Treatment, Clinical Challenges and Future Perspectives

Ewing sarcoma, a highly aggressive bone and soft-tissue cancer, is considered a prime example of the paradigms of a translocation-positive sarcoma: a genetically rather simple disease with a specific and neomorphic-potential therapeutic target, whose oncogenic role was irrefutably defined decades ago. This is a disease that by definition has micrometastatic disease at diagnosis and a dismal prognosis for patients with macrometastatic or recurrent disease. International collaborations have defined the current standard of care in prospective studies, delivering multiple cycles of systemic therapy combined with local treatment; both are associated with significant morbidity that may result in strong psychological and physical burden for survivors. Nevertheless, the combination of non-directed chemotherapeutics and ever-evolving local modalities nowadays achieve a realistic chance of cure for the majority of patients with Ewing sarcoma. In this review, we focus on the current standard of diagnosis and treatment while attempting to answer some of the most pressing questions in clinical practice. In addition, this review provides scientific answers to clinical phenomena and occasionally defines the resulting translational studies needed to overcome the hurdle of treatment-associated morbidities and, most importantly, non-survival.

Proton Beam Therapy for Children With Neuroblastoma: Experiences From the Prospective KiProReg Registry

Objective

Radiotherapy (RT) is an integral part of the interdisciplinary treatment of patients with high-risk neuroblastoma (NB). With the continuous improvements of outcome, the interest in local treatment strategies that reduce treatment-related side effects while achieving optimal oncological results is growing. Proton beam therapy (PBT) represents a promising alternative to conventional photon irradiation with regard to the reduction of treatment burden.

Method

Retrospective analysis of children with high or intermediate risk NB receiving PBT of the primary tumor site during first-line therapy between 2015 and 2020 was performed. Data from the prospective in-house registry Standard Protonentherapie WPE - Kinder- (KiProReg) with respect to tumor control and treatment toxicity were analyzed. Adverse events were classified according to CTCAE Version 4 (V4.0) before, during, and after PBT.

Results

In total, 44 patients (24 male, 20 female) with high (n = 39) or intermediate risk NB (n = 5) were included in the analysis. Median age was 3.4 years (range, 1.4-9.9 years). PBT doses ranged from 21.0 to 39.6 Gray (Gy) (median 36.0 Gy). Five patients received PBT to the MIBG-avid residual at the primary tumor site at time of PBT according to the NB-2004 protocol. In 39 patients radiation was given to the pre-operative tumor bed with or without an additional boost in case of residual tumor. After a median follow-up (FU) of 27.6 months, eight patients developed progression, either local recurrence (n = 1) or distant metastases (n = 7). Four patients died due to tumor progression. At three years, the estimated local control, distant metastatic free survival, progression free survival, and overall survival was 97.7, 84.1, 81.8, and 90.9%, respectively. During radiation, seven patients experienced higher-grade (CTCAE ≥ °3) hematologic toxicity. No other higher grade acute toxicity occurred. After PBT, one patient developed transient myelitis while receiving immunotherapy. No higher grade long-term toxicity was observed up to date.

Conclusion

PBT was a well tolerated and effective local treatment in children with high and intermediate risk NB. The role of RT in an intensive multidisciplinary treatment regimen remains to be studied in the future in order to better define timing, doses, target volumes, and general need for RT in a particularly sensitive cohort of patients.

[Influence of age on indications and modalities of radiation therapy: What to keep in mind for adolescents and young adults?]

When using radiation therapy for adolescents and young adults (AYA), paediatricians, adults' oncologists and radiation oncologists need to keep in mind several particularities through the whole therapeutic process. They embrace the indication, target volumes, prescribed dose, treatment techniques and follow-up. Indeed, the young age and the cancer features that characterised this population influence the modalities of irradiation. This article highlights the key points of AYA care with radiation therapy.

Prospective evaluation of multitarget treatment of pediatric patients with helical intensity-modulated radiotherapy

Background and purpose

Radiotherapy (RT) is persistently gaining significance in the treatment of pediatric tumors. However, individual features of a growing body and multifocal stages complicate this approach. Tomotherapy offers advantages in the treatment of anatomically complex tumors with low risks of side effects. Here we report on toxicity incidence and outcome of tomotherapy with a focus on multitarget RT (mtRT).

Materials and methods

From 2008 to 2017, 38 children diagnosed with sarcoma were treated with tomotherapy. The median age was 15 years (6–19 years). Toxicity was graded according to the Common Terminology Criteria for Adverse Events v.4.03 and classified into symptoms during RT, acutely (0–6 months) and late (>6 months) after RT, and long-term sideeffects (>24 months).

Results

The main histologies were Ewing sarcoma (n = 23 [61%]) and alveolar rhabdomyosarcoma (n = 5 [13%]). RT was performed with a median total dose of 54 Gy (40.5–66.0 Gy) and a single dose of 2 Gy (1.80–2.27 Gy). Twenty patients (53%) received mtRT. Median follow-up was 29.7 months (95% confidence interval 15.3–48.2 months) with a 5-year survival of 55.2% (±9.5%). The 5‑year survival rate of patients with mtRT (n = 20) was 37.1 ± 13.2%, while patients who received single-target RT (n = 18) had a 5-year survival rate of 75 ± 10.8%. Severe toxicities (grade 3 and 4) emerged in 14 patients (70%) with mtRT and 7 patients (39%) with single-target RT. Two non-hematological grade 4 toxicities occurred during RT: one mucositis and one radiodermatitis. After mtRT 5 patients had grade 3 toxicities acute and after single-target RT 4 patients. One patient had acute non-hematological grade 4 toxicities (gastritis, pericarditis, and pericardial effusion) after mtRT. Severe late effects of RT occurred in 2 patients after mtRT and in none of the single-target RT patients. No severe long-term side effects appeared.

Conclusion

Our results showed acceptable levels of acute and late toxicities, considering the highly advanced diseases and multimodal treatment. Hence, tomotherapy is a feasible treatment method for young patients with anatomically complex tumors or multiple targets. Especially mtRT is a promising and innovative treatment approach for pediatric sarcomas, delivering unexpectedly high survival rates for patients with multifocal Ewing sarcomas in this study, whereby the limited number of patients should invariably be considered in the interpretation.

Electronic supplementary material

The online version of this article (10.1007/s00066-020-01670-4) contains supplementary material, which is available to authorized users.

Risk Factors for Small Adult Height in Childhood Cancer Survivors

PURPOSE

Between 10% and 20% of childhood cancer survivors (CCS) experience impaired growth, leading to small adult height (SAH). Our study aimed to quantify risk factors for SAH or growth hormone deficiency among CCS.

METHODS

The French CCS Study holds data on 7,670 cancer survivors treated before 2001. We analyzed self-administered questionnaire data from 2,965 CCS with clinical, chemo/radiotherapy data from medical records. SAH was defined as an adult height ≤ 2 standard deviation scores of control values obtained from a French population health study.

RESULTS

After exclusion of 189 CCS treated with growth hormone, 9.2% (254 of 2,776) had a SAH. Being young at the time of cancer treatment (relative risk [RR], 0.91 [95% CI, 0.88 to 0.95] by year of age), small height at diagnosis (≤ 2 standard deviation scores; RR, 6.74 [95% CI, 4.61 to 9.86]), pituitary irradiation (5-20 Gy: RR, 4.24 [95% CI, 1.98 to 9.06]; 20-40 Gy: RR, 10.16 [95% CI, 5.18 to 19.94]; and ≥ 40 Gy: RR, 19.48 [95% CI, 8.73 to 43.48]), having received busulfan (RR, 4.53 [95% CI, 2.10 to 9.77]), or > 300 mg/m² of lomustine (300-600 mg/m²: RR, 4.21 [95% CI, 1.61 to 11.01] and ≥ 600 mg/m²: RR, 9.12 [95% CI, 2.75 to 30.24]) were all independent risk factors for SAH. Irradiation of ≥ 7 vertebrae (≥ 15 Gy on ≥ 90% of their volume) without pituitary irradiation increased the RR of SAH by 4.62 (95% CI, 2.77 to 7.72). If patients had also received pituitary irradiation, this increased the RR by an additional factor of 1.3 to 2.4.

CONCLUSION

CCS are at a high risk of SAH. CCS treated with radiotherapy, busulfan, or lomustine should be closely monitored for growth, puberty onset, and potential pituitary deficiency.

Radiation-Induced Myelitis: Initial and Follow-Up MRI and Clinical Features in Patients at a Single Tertiary Care Institution during 20 Years

Myelitis is a rare complication of radiation exposure to the spinal cord and is often a diagnosis of exclusion. A retrospective review of clinical records and serial imaging was performed to identify subjects with documented myelitis and a history of prior radiation. Eleven patients fulfilled the inclusion criteria. All patients had longitudinally extensive cord involvement with homogeneous precontrast T1 hyperintense signal in the adjacent vertebrae, corresponding to the radiation field. T2 signal abnormalities involving the central two-thirds of the cord were seen in 6/11 patients (55%). The degree of cord expansion and contrast enhancement was variable but was seen in 6 (54%) and 5 (45%) patients, respectively. On follow-up, 2 patients developed cord atrophy, while complete resolution was noted in 1. Clinical improvement was noted in 5 patients, with symptom progression in 2 patients. Our results suggest that radiation myelitis is neither universally progressive nor permanent, and some radiographic and clinical improvement may occur.

Temporal fate mapping reveals age-linked heterogeneity in naive T lymphocytes in mice

Understanding how our T-cell compartments are maintained requires knowledge of their population dynamics, which are typically quantified over days to weeks using the administration of labels incorporated into the DNA of dividing cells. These studies present snapshots of homeostatic dynamics and have suggested that lymphocyte populations are heterogeneous with respect to rates of division and/or death, although resolving the details of such heterogeneity is problematic. Here we present a method of studying the population dynamics of T cells in mice over timescales of months to years that reveals heterogeneity in rates of division and death with respect to the age of the host at the time of thymic export. We use the transplant conditioning drug busulfan to ablate hematopoetic stem cells in young mice but leave the peripheral lymphocyte compartments intact. Following their reconstitution with congenically labeled (donor) bone marrow, we followed the dilution of peripheral host T cells by donor-derived lymphocytes for a year after treatment. Describing these kinetics with mathematical models, we estimate rates of thymic production, division and death of naive CD4 and CD8 T cells. Population-averaged estimates of mean lifetimes are consistent with earlier studies, but we find the strongest support for a model in which both naive T-cell pools contain kinetically distinct subpopulations of older host-derived cells with self-renewing capacity that are resistant to displacement by naive donor lymphocytes. We speculate that these incumbent cells are conditioned or selected for increased fitness through homeostatic expansion into the lymphopenic neonatal environment.

[Which dose constraints on which critical organs in paediatric radiation therapy?]

Cancers in childhood are rare, representing 1% of all the cancers in developing countries. On the whole, the overall survival approaches 75% at 5 years. The radiation dose decrease in lots of indications as well as better optimized planning treatments lead to decrease the long-term toxicities in some indications. However, the radiation toxicity remains frequent, often specific of pediatric situations. Long-term toxicities are mainly neurologic, sensitive, endocrine, or linked to growth impairment (bones or muscular). Radio-induced second-cancers are also frequent after a long follow-up after cancer in childhood but will not be discussed here. Doses to critical organs as well as the most frequent radio-induced late-effects will be discussed in this paper.

A phase II study to determine the efficacy and safety of oral treosulfan in patients with advanced pre-treated Ewing sarcoma ISRCTN11631773

We report a prospective Phase II study of efficacy and toxicity for oral treosulfan in advanced Ewing sarcoma. Twenty patients, median age 19 years (range 7-39) from five UK sites, were treated with oral treosulfan 1 g/m(2) daily for 7 days in 28. Primary endpoint was objective response rate. Best response was stable disease in one patient. All patients died of progressive disease, after median 6.41 months. Median progression free survival was 1.8 months. Toxicity was minimal. No activity was demonstrated for treosulfan at this dose. Progression free survival data should be able to be used for comparison when planning future clinical trials.

[Localized Ewing sarcoma of the spine: a preliminary dose-escalation study comparing innovative radiation techniques in a single patient]

PURPOSE

Although radiosensitive, spinal locations of Ewing's sarcomas are challenging for the radiation oncologist due to poor radiation tolerance of the spinal cord. However, some favorable anatomical compartments - that may represent more than 20% - were associated with a better outcome and could benefit from a radiation dose escalation using the most recent radiation therapy techniques.

MATERIALS AND METHODS

We performed a dose escalation study on one patient, declined in two scenarios: (1) a tumour located within a single vertebral body and (2) a locally advanced disease involving the vertebral foramen and paraspinal soft tissues. Five dose-levels are proposed: 44.8Gy, 54.4Gy, 59.2Gy, 65.6Gy and 70.4Gy (1.6Gy per session, 8Gy per week). The 3D-conformational technique is compared with static intensity modulated radiation therapy (IMRT), helical tomotherapy, volumetric modulated arc therapy (VMAT), stereotactic body robotic radiation therapy (SBRT) and protontherapy (passive scattering). Two constraints had to be respected in order to skip to the next level: the planned target volume (PTV) coverage must exceed 95% and the D(2%) on the spinal cord shall not exceed a given constraint set at 50Gy in case 1 and 44Gy in case 2 due to initial neurological sufferance.

RESULTS

Only protontherapy, SBRT, helical tomotherapy and VMAT appear able to reach the last dose level while respecting the constraints in case 1. On the other hand, only helical tomotherapy seems capable of reaching 59.2Gy on the PTV in case 2.

CONCLUSION

With the most recent radiation therapy techniques, it becomes possible to deliver up to 70.4Gy in a favorable compartment in this sham patient. Unfavorable compartments can receive up to 59.2Gy. Definitive radiation therapy may be an interesting local treatment option to be validated in an early phase trial.

Management of bone tumours in paediatric oncology

The management of bone tumours in paediatric oncology requires careful multidisciplinary planning due to the need for multimodal therapy approaches. The non-specific symptoms often lead to a delayed definitive diagnosis of a bone tumour. Imaging procedures are of major importance for an individualised and optimised treatment planning. They have to be carried out before any surgery, including biopsies. The introduction of multi-agent chemotherapy has led to a significant improvement in survival rates in patients suffering from Ewing's sarcomas and osteosarcomas. However, local therapy still remains indispensable in order to achieve long-term survival. For osteosarcoma, surgery remains the only adequate local therapy modality. Radiotherapy may be considered if surgery is not feasible. In these cases, high radiation doses need to be applied. The choice for local therapy modality is not as clear in patients with Ewing's sarcoma. Today, surgery is often preferred if a wide or at least marginal resection can be carried out. Additional radiotherapy is advised in patients with marginal/intralesional resection or poor histological response to induction chemotherapy. Definitive radiotherapy is recommended for inoperable lesions. In the future, new radiotherapy approaches, such as intensity-modulated radiotherapy or proton therapy, may yield better results with minor risks of late effects.