Current strategies and challenges in treatment of childhood rhabdomyosarcoma

Prognostic factors of primary intrascrotal rhabdomyosarcoma in children: a population-based study

PURPOSE

Primary intrascrotal rhabdomyosarcoma (RMS) is a rare and aggressive tumor. The purpose of this study was to investigate the prognostic factors of intrascrotal RMS in children.

METHODS

All pediatric patients with intrascrotal RMS diagnosed between 2000 and 2018 were identified using the Surveillance, Epidemiology, and End Results (SEER) database. To compare survival curves, the log-rank test was employed. A multivariate Cox proportional hazards model was developed to investigate the effect of each factor on overall survival (OS). A nomogram was created using the outcomes of the Cox regression model.

RESULTS

A total of 102 pediatric patients with intrascrotal RMS were identified. Overall survival rates for all patients were 90.6% at 3-year and 87.2% at 5-year, respectively. Survival rates differed significantly by SEER stage and surgery; however, chemotherapy and removal of lymph nodes showed no significant difference. The outcome of Cox proportional hazard regression revealed that SEER stage and surgery were important independent predictors in this model. Furthermore, we developed a nomogram for predicting OS in pediatric intrascrotal RMS based on the Cox regression model. The risk of death increased with stage in patients. Additionally, patients who underwent surgery had a lower mortality risk than those who did not.

CONCLUSIONS

Our findings show that SEER stage and surgery are the most important indicators of OS in children with intrascrotal RMS, providing critical epidemiological information for clinical therapy.

A Retrospective Study of Renal Growth Changes after Proton Beam Therapy for Pediatric Malignant Tumor

The purpose of this study was to analyze renal late effects after proton beam therapy (PBT) for pediatric malignant tumors. A retrospective study was performed in 11 patients under 8 years of age who received PBT between 2013 and 2018. The kidney was exposed in irradiation of the primary lesion in all cases. Kidney volume and contour were measured on CT or MRI. Dose volume was calculated with a treatment-planning system. The median follow-up was 24 months (range, 11-57 months). In irradiated kidneys and control contralateral kidneys, the median volume changes were -5.63 (-20.54 to 7.20) and 5.23 (-2.01 to 16.73) mL/year; and the median % volume changes at 1 year were -8.55% (-47.52 to 15.51%) and 9.53% (-2.13 to 38.78%), respectively. The median relative volume change for irradiated kidneys at 1 year was -16.42% (-52.21 to -4.53%) relative to control kidneys. Kidneys irradiated with doses of 10, 20, 30, 40, and 50 GyE had volume reductions of 0.16%, 0.90%, 1.24%, 2.34%, and 8.2% per irradiated volume, respectively. The larger the irradiated volume, the greater the kidney volume was lost. Volume reduction was much greater in patients aged 4-7 years than in those aged 2-3 years. The results suggest that kidneys exposed to PBT in treatment of pediatric malignant tumor show continuous atrophy in follow-up. The degree of atrophy is increased with a higher radiation dose, greater irradiated volume, and older age. However, with growth and maturation, the contralateral kidney becomes progressively larger and is less affected by radiation.

Multimodality treatment including whole pleura radiation therapy for DICER1-associated pediatric pleuropulmonary blastoma

Limited data are available regarding radiation therapy in pediatric pleuropulmonary blastoma (PPB). We report the case of a 3-year-old girl with type II PPB successfully treated with trimodality therapy including multiagent chemotherapy, resection, and whole pleura radiation therapy. While longer follow-up is required to confirm ultimate local tumor control and long-term post-treatment sequelae, currently 3.5 years following therapy, she is well, without recurrent disease or observable toxicity. The goal of this report is to add our experience to the literature regarding PPB, its management, and treatment, as prospective randomized controlled trials are not feasible due to the rarity of this disease.

Vincetoxicum arnottianum modulates motility features and metastatic marker expression in pediatric rhabdomyosarcoma by stabilizing the actin cytoskeleton

Background

Prevention of metastatic invasion is one of the main challenges in the treatment of alveolar rhabdomyosarcoma. Still the therapeutic options are limited. Therefore, an anti-tumor screening was initiated focusing on the anti-metastatic and anti-invasion properties of selected medicinal plant extracts and phytoestrogens, already known to be effective in the prevention and treatment of different cancer entities.

Methods

Treatment effects were first evaluated by cell viability, migration, invasion, and colony forming assays on the alveolar rhabdomyosarcoma cell line RH-30 in comparison with healthy primary cells.

Results

Initial anti-tumor screenings of all substances analyzed in this study, identified the plant extract of Vincetoxicum arnottianum (VSM) as the most promising candidate, harboring the highest anti-metastatic potential. Those significant anti-motility properties were proven by a reduced ability for migration (60%), invasion (99%) and colony formation (61%) under 48 h exposure to 25 μg/ml VSM. The restricted motility features were due to an induction of the stabilization of the cytoskeleton – actin fibers were 2.5-fold longer and were spanning the entire cell. Decreased proliferation (PCNA, AMT, GCSH) and altered metastasis (e. g. SGPL1, CXCR4, stathmin) marker expression on transcript and protein level confirmed the significant lowered tumorigenicity under VSM treatment. Finally, significant alterations in the cell metabolism were detected for 25 metabolites, with levels of uracil, N-acetyl serine and propanoyl phosphate harboring the greatest alterations. Compared to the conventional therapy with cisplatin, VSM treated cells demonstrated a similar metabolic shutdown of the primary cell metabolism. Primary control cells were not affected by the VSM treatment.

Conclusions

This study revealed the VSM root extract as a potential, new migrastatic drug candidate for the putative treatment of pediatric alveolar rhabdomyosarcoma with actin filament stabilizing properties and accompanied by a marginal effect on the vitality of primary cells.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-021-03299-x.

Primary intratesticular rhabdomyosarcoma in children: a case report and review of the literature

Background

The importance of this paper is to help to emphasize the importance of chemotherapy for children with pure intratesticular rhabdomyosarcoma after radical inguinal orchiectomy is done as first treatment of rhabdomyosarcoma. The information provided in this paper about the follow-up outcomes of the patient described in this paper, it highlights that, recurrence and even metastasis of intratesticular rhabdomyosarcoma in children are more likely to occur if surgery it not combined with chemotherapy.

Case presentation

Herein, we present a 6-year old African male child with a 3 months history of a painless right intratesticular tumour. The tumour was poorly vascularized and was in continuity with the spermatic cord. Pelvic computer tomography (CT) scan showed a heterogeneous mass with well-defined margins without microcalcification and multiple bilateral inguinal enlarged lymph nodes were noticed without pelvic lymphadenopathy. The tumour measured 3.8 × 2.8 × 3.9 cm. The tumour marker panel showed: lactate dehydrogenase of (472 UI/l), alpha-fetoprotein (1.43 UI/ml) and human chorionic gonadotrophin beta (2.9 mUI/ml). Microscopically, the tumour was composed of small to medium size undifferentiated cells. These were oval to spindle, hyperchromatic cells to stromal myxoid degeneration were noted. Tunica albuginea and rete testis both were infiltrated by tumour. The tumour showed high mitotic count which measured 50 mitoses per 10 High Power Field (HPF). The diagnosis of rhabdomyosarcoma (RMS) was confirmed by immunohistochemistry (IHC) testing using myoD antibody which showed strong and diffuse intranuclear staining of the tumour cells. Currently, he is on cyclophosphamide and vincristine chemotherapy regime and his condition has improved much.

Conclusions

The experience obtained from the index case is crucial for the management of patients with intratesticular rhabdomyosarcoma which should always make sure that radical inguinal orchiectomy is covered by chemotherapy and/or radiotherapy. This will potentially lower the possibilities of recurrence and/or metastasis of the tumour, hence improving the prognosis of the patients. We report the clinical, radiological, and laboratory characteristics as well as the outcome of the patient.

Interventional radiotherapy (brachytherapy) achieves very good long-term quality of life in children and adolescents with soft-tissue sarcoma

BACKGROUND

Effective local therapy (surgery, radiation) and systemic multidrug chemotherapy are mandatory for curing childhood sarcoma. The standard radiation therapy for pediatric patients with soft-tissue sarcoma (STS) is external beam radiotherapy (EBRT). Because EBRT may cause long-term side effects with adverse effects on the patients' health and quality of life (QoL), alternative strategies are required. Interventional radiotherapy (IRT; brachytherapy) is established as a standard treatment for several tumors in adulthood. Single-center series have reported low levels of late effects and improved QoL in survivors treated with IRT in childhood. However, IRT is still applied infrequently in pediatric patients.

METHODS

Thirty patients with STS were treated with IRT between 1992 and 2012 at the University Hospital Schleswig Holstein, Germany. Five patients were lost to follow-up, and 25 patients (mean age at time of data collection 24.8 years [range, 10.7-36.1]) could be analyzed focusing on overall survival and QoL (EORTC-C30 questionnaire). For more detailed information regarding general and health-specific questions, a separate questionnaire was developed.

RESULTS

Nineteen of 25 patients were alive 13.4 [1.6-25.2] years after first cancer disease, and the three-year overall survival was 76% (SE, 0.09). The score of QoL/global health status (76.2 [16.6-100]) in our patients outvalues the European (66.1) and equals the German (75.9) reference value.

CONCLUSION

IRT is an effective treatment option for pediatric patients with localized STS. Its role among other radiation dose-sparing techniques such as proton beam therapy has to be defined in prospective studies.

TP53 in bone and soft tissue sarcomas

Genomic and functional study of existing and emerging sarcoma targets, such as fusion proteins, chromosomal aberrations, reduced tumor suppressor activity, and oncogenic drivers, is broadening our understanding of sarcomagenesis. Among these mechanisms, the tumor suppressor p53 (TP53) plays significant roles in the suppression of bone and soft tissue sarcoma progression. Although mutations in TP53 were thought to be relatively low in sarcomas, modern techniques including whole-genome sequencing have recently illuminated unappreciated alterations in TP53 in osteosarcoma. In addition, oncogenic gain-of-function activities of missense mutant p53 (mutp53) have been reported in sarcomas. Moreover, new targeting strategies for TP53 have been discovered: restoration of wild-type p53 (wtp53) activity through inhibition of TP53 negative regulators, reactivation of the wtp53 activity from mutp53, depletion of mutp53, and targeting of vulnerabilities in cells with TP53 deletions or mutations. These discoveries enable development of novel therapeutic strategies for therapy-resistant sarcomas. We have outlined nine bone and soft tissue sarcomas for which TP53 plays a crucial tumor suppressive role. These include osteosarcoma, Ewing sarcoma, chondrosarcoma, rhabdomyosarcoma (RMS), leiomyosarcoma (LMS), synovial sarcoma, liposarcoma (LPS), angiosarcoma, and undifferentiated pleomorphic sarcoma (UPS).

Diagnosis and Multimodal Treatment of Metastatic Maxillofacial Juvenile Embryonal Rhabdomyosarcoma in a Young Golden Retriever

A 2 yr old male castrated golden retriever was evaluated for a rapidly progressing maxillofacial spindle cell tumor. On examination, an ill-defined left maxillary mass, a 2 cm swelling under the left eye, and an enlarged left mandibular lymph node were noted. The dog was bright and alert but appeared painful upon jaw extension. Cytology from the lymph node revealed metastatic disease. Thoracic radiographs and computed tomography scan revealed pulmonary nodules. Computed tomography of the head and neck revealed a 6.7 × 4.1 × 6.5 cm mass at the rostral aspect of the left zygomatic arch invading the orbit. A second opinion of the biopsy specimen in conjunction with positive immunohistochemical staining for desmin led to a revised diagnosis of rhabdomyosarcoma. Treatment consisted of three doses of palliative radiation therapy, in 8 Gy fractions, and chemotherapy with vincristine, cyclophosphamide, and doxorubicin. A rapid clinical response was noted shortly after treatment initiation; however, the response was temporary, and the dog was euthanized due to widespread metastatic disease and associated clinical signs 74 days after initial therapy. This is one of the first reports describing positive results from multimodal treatment with chemotherapy and radiation therapy of a maxillofacial juvenile rhabdomyosarcoma in the veterinary literature.

Non-Rhabdomyosarcoma Soft Tissue Sarcomas in Children: A Surveillance, Epidemiology, and End Results Analysis Validating COG Risk Stratifications

PURPOSE

Non-rhabdomyosarcoma soft tissue sarcomas (NRSTS) are a heterogeneous group of sarcomas that encompass over 35 histologies. With an incidence of ∼500 cases per year in the United States in those <20 years of age, NRSTS are rare and therefore difficult to study in pediatric populations. We used the large Surveillance, Epidemiology, and End Results (SEER) database to validate the prognostic ability of the Children's Oncology Group (COG) risk classification system and to define patient, tumor, and treatment characteristics.

METHODS AND MATERIALS

From SEER data from 1988 to 2007, we identified patients ≤18 years of age with NRSTS. Data for age, sex, year of diagnosis, race, registry, histology, grade, primary size, primary site, stage, radiation therapy, and survival outcomes were analyzed. Patients with nonmetastatic grossly resected low-grade tumors of any size or high-grade tumors ≤5 cm were considered low risk. Cases of nonmetastatic tumors that were high grade, >5 cm, or unresectable were considered intermediate risk. Patients with nodal or distant metastases were considered high risk.

RESULTS

A total of 941 patients met the review criteria. On univariate analysis, black race, malignant peripheral nerve sheath (MPNST) histology, tumors >5 cm, nonextremity primary, lymph node involvement, radiation therapy, and higher risk group were associated with significantly worse overall survival (OS) and cancer-specific survival (CSS). On multivariate analysis, MPNST histology, chemotherapy-resistant histology, and higher risk group were significantly poor prognostic factors for OS and CSS. Compared to low-risk patients, intermediate patients showed poorer OS (hazard ratio [HR]: 6.08, 95% confidence interval [CI]: 3.53-10.47, P<.001) and CSS (HR: 6.27; 95% CI: 3.44-11.43, P<.001), and high-risk patients had the worst OS (HR: 13.35, 95% CI: 8.18-21.76, P<.001) and CSS (HR: 14.65, 95% CI: 8.49-25.28, P<.001).

CONCLUSIONS

The current COG risk group stratification for children with NRSTS has been validated with a large number of children in the SEER database.