Parameningeal rhabdomyosarcoma in pediatric age: results of a pooled analysis from North American and European cooperative groups

Current status of head and neck sarcomas in Japan in 2016-2019: an analysis using the national cancer registry

BACKGROUND

Head and neck sarcomas are especially rare in Asia, leading to limited clinical evidence. This study aimed to investigate the incidence, clinical features, treatment status, and outcome of these sarcomas using data from the National Cancer Registry in Japan.

METHODS

All head and neck sarcomas diagnosed between 2016 and 2019 and recorded in the National Cancer Registry were analyzed. Data on sex, age, primary site, histological type, stage, treatment modality, and prognostic information were collected. Age-adjusted incidence and 3-year survival rates of patients with head and neck sarcomas were calculated.

RESULTS

Overall, 635 head and neck sarcoma patients were identified. Head and neck sarcoma occurred more frequently in men and patients in their 70 s. The age-adjusted annual incidence rate was 0.125 per 100,000 patients in the 2015 Japanese model or 0.089 per 100,000 patients in the world population model. The nasal cavity and paranasal sinuses were the most frequent primary sites, with rhabdomyosarcoma as the most common histologic type. Treatment typically involved chemotherapy and/or radiation therapy for rhabdomyosarcoma and Ewing's sarcoma, whereas surgical approaches for other types. Three-year survival rate of head and neck sarcoma patients was 64.8%.

CONCLUSIONS

Head and neck sarcomas occurred rarely, but most frequently in the nasal cavity and paranasal sinuses in Japan. Poor outcomes were observed for sarcoma patients than for non-sarcoma head and neck cancer patients.

Nomogram to predict prognosis of head and neck rhabdomyosarcoma patients in children and adolescents

Purpose

This study aims to explore the prognostic factors of head and neck rhabdomyosarcoma (HNRMS) in children and adolescents and construct a simple but reliable nomogram model for estimating overall survival (OS) of patients.

Methods

Data of all HNRMS patients during 2004-2018 were identified from the Surveillance, Epidemiology, and End Result database. Kaplan-Meier method was performed to calculate OS stratified by subgroups and comparison between subgroups was completed by log-rank test. Univariate and multivariate Cox regressions analysis were employed for identifying independent predictors, which subsequently were used for a predictive model by R software, and the efficacy of the model was evaluated by applying receiver operating curve (ROC), calibration and decision curve analysis (DCA).

Results

A total of 446 patients were included in the study. The 1-, 3-, and 5-year OS rate of the whole cohort was 90.6%, 80.0%, and 75.5%, respectively. The results of univariate and multivariate Cox regression analysis indicated that the primary site in parameningeal region, alveolar RMS histology, M1 stage, IRS stage 4, surgery, and chemotherapy were significant prognostic factors (all P<0.05). The performance of nomogram model was validated by discrimination and calibration, with AUC values of 1, 3, and 5 years OS of 0.843, 0.851, and 0.890, respectively.

Conclusion

We constructed a prognostic nomogram model for predicting the OS in HNRMS patients in children and adolescents and this model presented practical and applicable clinical value to predict survival when choosing treatment strategies.

International Consensus Statement on Allergy and Rhinology: Sinonasal Tumors

BACKGROUND

Sinonasal neoplasms, whether benign and malignant, pose a significant challenge to clinicians and represent a model area for multidisciplinary collaboration in order to optimize patient care. The International Consensus Statement on Allergy and Rhinology: Sinonasal Tumors (ICSNT) aims to summarize the best available evidence and presents 48 thematic and histopathology-based topics spanning the field.

METHODS

In accordance with prior International Consensus Statement on Allergy and Rhinology documents, ICSNT assigned each topic as an Evidence-Based Review with Recommendations, Evidence-Based Review, and Literature Review based on the level of evidence. An international group of multidisciplinary author teams were assembled for the topic reviews using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses format, and completed sections underwent a thorough and iterative consensus-building process. The final document underwent rigorous synthesis and review prior to publication.

RESULTS

The ICSNT document consists of four major sections: general principles, benign neoplasms and lesions, malignant neoplasms, and quality of life and surveillance. It covers 48 conceptual and/or histopathology-based topics relevant to sinonasal neoplasms and masses. Topics with a high level of evidence provided specific recommendations, while other areas summarized the current state of evidence. A final section highlights research opportunities and future directions, contributing to advancing knowledge and community intervention.

CONCLUSION

As an embodiment of the multidisciplinary and collaborative model of care in sinonasal neoplasms and masses, ICSNT was designed as a comprehensive, international, and multidisciplinary collaborative endeavor. Its primary objective is to summarize the existing evidence in the field of sinonasal neoplasms and masses.

Local Treatment of Children Suffering From Parameningeal Rhabdomyosarcoma: A Retrospective Single-Center Study From China

BACKGROUND

Treatment for parameningeal rhabdomyosarcoma (PM-RMS) has been a challenge since local control is difficult. The goal of this study was to analyse the impact of different local treatment approaches on childhood PM-RMS patients and help dispel the doubt that whether secondary radical surgery (SRS) should be encouraged in the management of PM-RMS.

METHODS

A total of 17 children with PM-RMS who received unified systemic chemotherapy and individualized local therapy such as radiotherapy (RT) and/or SRS were included in this retrospective study. The overall survival (OS) and event free survival (EFS) were compared between groups adopting different local strategies.

RESULTS

The 3-year OS and EFS of our PM-RMS patients was 75.5% and 56.5% respectively. The OS and EFS of patients who received SRS were both significantly lower than that of the non-SRS group (3-year OS: 50.0% vs 90.0%, P = .031; 3-year EFS: 33.3% vs 60.6%, P = .020). The OS and EFS of the patients who received RT was higher than that of the patients of the non-RT group (3-year OS: 85.6% vs 0%, P = .001; 3-year EFS: 64.0% vs 0%, P = .011).

CONCLUSION

This study illustrates that SRS was associated with poor prognosis of PM-RMS and should not be routinely performed. Optimized RT strategies along with more intensive chemotherapy may be alternative options to improve the survival of patients with PM-RMS. Multi-center, large sample and prospective studies are needed to further validate these findings.

Radiotherapy and long-term sequelae in pediatric patients with parameningeal rhabdomyosarcoma: Results of two Cooperative Weichteilsarkom Studiengruppe (CWS) trials and one registry

BACKGROUND

Parameningeal location of rhabdomyosarcoma (PM RMS) is known to be an unfavorable prognostic factor. Scarce data are available on radiotherapy (RT) concepts with regard to outcome.

METHODS

Treatment and outcome of 395 children with PM RMS registered within two Cooperative Weichteilsarkom Studiengruppe (CWS) trials and one registry (1995-2021) were evaluated.

RESULTS

Patients were IRS group II (n = 15) and III (n = 380) and received systemic treatment according to the enrolled protocols: I2VA (n = 172), VAIA/CEVAIE (n = 223). Delayed resection was performed in 88/395 (22%) patients, and RT was additionally given in 79/88 (90%) resected patients. RT was the predominant local treatment in 355/395 (90%) patients: hyperfractionated accelerated photon (HART; n = 77), conventionally fractionated photon (n = 91) or proton beam (n = 126), brachytherapy (n = 4), heavy ions (n = 1), not available (n = 56). In the subgroup of RT as only local treatment (n = 278), no intracranial tumor extension and complete remission at end of treatment were significant positive prognostic factors. No significant difference on tumor outcome was seen between different radiotherapy concepts. Long-term toxicity with mostly endocrinological and visual deficiencies was reported in 161/279 (58%) surviving patients with a lower trend after proton beam RT (48%) when compared to HART or conventionally fractionated photon RT (71% and 72%, respectively). Ten-year event-free and overall survival in the overall group were 62% (±5, 95% confidence interval [CI]) and 67% (±5, 95% CI); in the RT-only group 67% (±6, 95% CI) and 71% (±6, 95% CI), respectively.

CONCLUSION

CWS data confirm the recent RT concept in PM RMS. Long-term sequelae as endocrinological and visual deficiencies need to be addressed.

Latissimus dorsi free flap reconstruction of a temporal defect following pediatric oncologic surgery: Case report + literature review

INTRODUCTION

Rhabdomyosarcoma (RMS) is the most common soft-tissue sarcoma in children and adolescents. Around 35 % of pediatric sarcomas occur in the head and neck region. Consequently, RMS is considered the most common type of childhood malignancy diagnosed in this region.

OBSERVATION

We report the clinical case of a 6 years old patient, who presented a large temporal hollowing following oncological excision surgery for temporal rhabdomyosarcoma. He underwent surgical reconstruction to fill the right temporalis fossa using a latissimus dorsi muscle free flap micro-anastomosed to the lingual vessels.

DISCUSSION

This clinical case highlights the value of plastic surgery in oncological reconstruction, which, combined with a multidisciplinary and collective approach, enables a holistic approach and facilitates socio-psychological integration after oncological surgery in the pediatric population.

Survival outcomes including salvage therapy of adult head and neck para-meningeal rhabdomyosarcoma: a multicenter retrospective study from Japan

BACKGROUND

Rhabdomyosarcoma is the most common soft tissue sarcoma in children, but rare in adults. Para-meningeal rhabdomyosarcoma in head and neck (PM-HNRMS) is less applicable for surgery due to the anatomic reason. PM-HNRMS has a poor prognosis in children. However, its clinical outcomes remain unclear in adults due to the rarity. Further, there is almost no detailed data about salvage therapy.

METHODS

We retrospectively examined the adult patients with PM-HNRMS treated at institutions belonging to the Kyushu Medical Oncology Group from 2009 to 2022. We evaluated the overall survival (OS) and progression-free survival (PFS) of the patients who received a first-line therapy. We also reviewed the clinical outcomes of patients who progressed against a first-line therapy and received salvage therapy.

RESULTS

Total 11 patients of PM-HNRMS received a first-line therapy. The characteristics were as follows: median age: 38 years (range 25 - 63 years), histology (alveolar/spindle): 10/1, and risk group (intermediate/high): 7/4. As a first-line therapy, VAC and ARST0431-based regimen was performed in 10 and 1 patients, respectively. During a first-line therapy, definitive radiation for all lesions were performed in seven patients. The median PFS was 14.2 months (95%CI: 6.0 - 25.8 months): 17.1 months (95%CI: 6.0 - not reached (NR)) for patients with stage I-III and 8.5 months (95%CI: 5.2 - 25.8 months) for patients with stage IV. The 1-year and 3-year PFS rates were 54.5% and 11.3% for all patients. Median OS in all patients was 40.8 months (95%CI: 12.1 months-NR): 40.8 months (95%CI: 12.1 - NR) for patients with stage I-III and NR for patients with stage IV. The 5-year OS rate was 48.5% for all patients. Among seven patients who received salvage therapy, three are still alive, two of whom remain disease-free for over 4 years after completion of the last therapy. Those two patients received multi-modal therapy including local therapy for all detected lesions.

CONCLUSION

The cure rate of adult PM-HNRMS is low in spite of a first-line therapy in this study. Salvage therapy might prolong the survival in patients who received the multi-modal therapy including local therapy for all detected lesions.

Adaptive Proton Therapy for Pediatric Parameningeal Rhabdomyosarcoma: On-Treatment Anatomic Changes and Timing to Replanning

PURPOSE

To characterize on-treatment changes in GTV morphology in children with parameningeal rhabdomyosarcoma receiving upfront proton therapy with concurrent chemotherapy and thereby provide guidance on the timing of on-treatment imaging and adaptive replanning.

METHODS AND MATERIALS

GTV was delineated on 86 simulation and weekly MR images of 15 prospectively enrolled patients (aged 1-21 years). Temporal changes from baseline in volume and surface (95% Hausdorff distance) were analyzed in relation to the need for plan verification and the resultant doses with hypothetical no treatment adaptation.

RESULTS

The median time was 6 days from the initiation of chemotherapy to CT+MR simulation and 15 days from the simulation to the start of radiotherapy. All but 1 patient showed a continuous decrease in GTV (0.16-1.52%/day) after simulation. At 3 weeks from simulation, 10 of 15 patients exhibited a significant reduction in volume (median, 20%; range, 6-29%). Without replanning, these changes could lead to a reduction in CTV V95 by 7-14% (n = 2) and/or an increase in D0.01 cc/Dmean of adjacent organs at risk by 6-21% of the prescribed target dose (n = 7). Significant dosimetric consequences occurred in cases with (1) a considerable weight gain, (2) shrinkage of the skin surface, or (3) tumor regression in the oral or nasal cavity and sinus that altered air-tissue components in the beam path. The subsequent GTV and dosimetry after 3 weeks from simulation (4 weeks from chemotherapy initiation) demonstrated a relatively stable trend.

CONCLUSIONS

On-treatment imaging at 3 weeks after simulation is recommended, if the simulation is performed at 1 week after the initiation of chemotherapy, to detect significant anatomic changes that could result in >5% deviation from planned target coverage and/or organ doses in pediatric patients with parameningeal rhabdomyosarcoma receiving early proton therapy.

Efficacy and safety of proton beam therapy for rhabdomyosarcoma: a systematic review and meta-analysis

OBJECTIVE

This study aimed to evaluate and conduct a meta-analysis on the efficacy and safety of proton beam therapy (PBT) for rhabdomyosarcoma (RMS).

METHODS

We searched for articles using PubMed, Embase, Cochrane Library, and Web of Science databases from their inception to December 22, 2022. Two researchers independently screened literature and extracted data. Statistical analyses were performed using STATA version 14.0.

RESULTS

We got 675 candidate articles, of which 11 studies were included in our study according to the inclusion and exclusion criteria. Of the 544 RMS patients who received PBT. The local control (LC) rate at 1, 2, 3, 4, and 5 years were 96% (95% confidence interval (CI) 0.91-1.01), 93% (95% CI 0.86-1.00), 78% (95% CI 0.71-0.85), 85% (95% CI 0.78-0.92), and 84% (95% CI 0.74-0.95), respectively. The progression-free survival (PFS) rate at 1, 2, 3, 4, and 5 years were 82% (95% CI 0.72-0.92), 73% (95% CI 0.61-0.84), 63% (95% CI 0.47-0.79), 64% (95% CI 0.54-0.74), and 76% (95% CI 0.59-0.94), respectively. The overall survival (OS) rate at 1, 2, 3, 4, and 5 years were 93% (95% CI 0.86-1.00), 85% (95% CI 0.76-0.95), 80% (95% CI 0.63-0.96), 71% (95% CI 0.62-0.80), and 82% (95% CI 0.71-0.94), respectively. Acute and late toxicities were mainly grades 1 to 2 in all studies.

CONCLUSION

As an advantageous RT technique, PBT is an emerging option for patients with RMS, particularly children and adolescents patients. The data showed that PBT is a feasible, safe, and effective modality for RMS, showing promising LC, OS, PFS, and lower acute and late toxicities. PROSPERO registration number: CRD42022329154.

Non-inferior efficacy of non-surgical treatment to surgical treatment in patients with nonmetastatic head and neck rhabdomyosarcoma: a SEER-based study

PURPOSE

Head and neck rhabdomyosarcoma (HNRMS) is a rare but aggressive malignant neoplasm. Given the young patient age and critical anatomy of the head and neck, performing surgery on the primary tumor still remains debatable. This study aimed to evaluate the impact of the non-surgery-based treatment versus surgery-based treatment on patients with nonmetastatic HNRMS.

METHODS

Patients diagnosed with nonmetastatic HNRMS between 2004 and 2015 from the Surveillance, Epidemiology, and End Results (SEER) database were enrolled in our study. Inverse probability treatment weighting (IPTW) method was employed to balance confounding factors between surgery and non-surgery groups. Kaplan-Meier methods and COX regression analyses were used to analyze survival outcomes of overall survival (OS) and cancer-specific survival (CSS). Prognostic nomogram was established to predict survival.

RESULTS

A total of 260 eligible patients were extracted from the SEER database. Kaplan-Meier survival curves revealed that there was no significant difference in OS and CSS between the surgery and non-surgery groups both before and after IPTW (p > 0.05). Cox regression analyses and IPTW-adjusted Cox regression analyses for both OS and CSS showed similar survival between the two groups. Prognostic factors were explored and a nomogram for patients in the surgery group was constructed. Risk stratification based on the nomogram indicated that patients in surgery-high-risk group did not benefit from primary surgery. While those in surgery-low-risk group had an equal survival outcome to those in non-surgery group.

CONCLUSIONS

Our study revealed that compared to patients receiving surgery, those not receiving surgery had similar survival outcomes for nonmetastatic HNRMS. Our established nomogram may serve as a practical tool for individual prognostic evaluations.

Patterns of Hearing Loss in Irradiated Survivors of Head and Neck Rhabdomyosarcoma

PURPOSE

The frequency and patterns of HL in a HNRMS survivor cohort were investigated. A dose-effect relationship between the dose to the cochlea and HL was explored.

METHODS

Dutch survivors treated for HNRMS between 1993 and 2017 with no relapse and at least two years after the end of treatment were eligible for inclusion. The survivors were evaluated for HL with pure-tone audiometry. HL was graded according to the Muenster, Common Terminology Criteria for Adverse Events (CTCAE) v4.03 and International Society for Paediatric Oncology (SIOP) classification. We defined deleterious HL as Muenster ≥ 2b, CTCAE ≥ 2, and SIOP ≥ 2. Mixed-effects logistic regression was used to search for the dose-effect relationship between the irradiation dose to the cochlea and the occurrence of HL.

RESULTS

Forty-two HNRMS survivors underwent pure-tone audiometry. The Muenster, CTCAE and SIOP classification showed that 19.0% (n = 8), 14.2% (n = 6) and 11.9% (n = 5) of survivors suffered from HL, respectively. A low-frequency HL pattern with normal hearing or milder hearing loss in the higher frequencies was seen in four survivors. The maximum cochlear irradiation dose was significantly associated with HL (≥Muenster 2b) (p = 0.047). In our series, HL (≥Muenster 2b) was especially observed when the maximum dose to the cochlea exceeded 19 Gy.

CONCLUSION

HL occurred in up to 19% of survivors of HNRMS. More research is needed on HL patterns in HNRMS survivors and on radiotherapy dose-effect relationships.

Creating a data commons: The INternational Soft Tissue SaRcoma ConsorTium (INSTRuCT)

In this article, we will discuss the genesis, evolution, and progress of the INternational Soft Tissue SaRcoma ConsorTium (INSTRuCT), which aims to foster international research and collaboration focused on pediatric soft tissue sarcoma. We will begin by highlighting the current state of clinical research for pediatric soft tissue sarcomas, including rhabdomyosarcoma and non-rhabdomyosarcoma soft tissue sarcoma. We will then explore challenges and research priorities, describe the development of INSTRuCT, and discuss how the consortium aims to address key research priorities.

Local control of parameningeal rhabdomyosarcoma: An expert consensus guideline from the International Soft Tissue Sarcoma Consortium (INSTRuCT)

The International Soft Tissue Sarcoma Database Consortium (INSTRuCT) consists of a collaboration between the Children's Oncology Group (COG) Soft Tissue Sarcoma Committee, the European pediatric Soft Tissue Sarcoma Study Group (EpSSG), and the Cooperative Weichteilsarkom Studiengruppe (CWS). As part of the larger initiative of INSTRuCT to provide consensus expert opinions for clinical treatment of pediatric soft tissue sarcoma, we sought to provide updated, evidenced-based consensus guidelines for local treatment of parameningeal rhabdomyosarcoma using both existing literature as well as recommendations from the relevant cooperative group clinical trials. Overall, parameningeal rhabdomyosarcoma represents a distinctly challenging disease to treat, given its location near many critical structures in the head and neck, frequently advanced local presentation, and predilection for local failure. Definitive chemoradiation remains the standard treatment approach for parameningeal rhabdomyosarcoma, with surgery often limited to biopsy or salvage therapy for recurrent disease. In this consensus paper, we specifically discuss consensus guidelines and evidence for definitive local management with radiotherapy, with a focus on imaging for radiotherapy planning, dose and timing of radiation, approach for nodal irradiation, various radiation techniques, including proton therapy, and the limited role of surgical resection.

Parameningeal alveolar rhabdomyosarcoma in a child

This is the case of a parameningeal alveolar rhabdomyosarcoma (ARMS) in a 13-year-old boy who presented with painless loss of vision in the right eye, but very few other physical signs. The ARMS diagnosis was confirmed with imaging and molecular characterisation of the tumour. Despite tolerating the initial chemotherapy and radiotherapy regimens, there was leptomeningeal recurrence and the patient unfortunately passed away. Parameningeal ARMS occurs in an area of the body, which leads to a wide variety of possible presenting symptoms, creating a long list of differentials that can delay treatment. This tumour subtype has a poor prognosis, and due to the location of the tumour around vital structures in the head, treatment toxicities must be taken into account. This highlights the necessity for having a strong index of suspicion for this tumour in atypical presentations in children, and the necessity for prompt treatment to prevent leptomeningeal disease from occurring.

The Impact of Radiation Therapy in Children and Adolescents With Metastatic Rhabdomyosarcoma

PURPOSE

There is limited evidence to define the role of radiation therapy in children with metastatic rhabdomyosarcoma (mRMS). In the international BERNIE study, children with mRMS or non-RMS soft tissue sarcoma were randomized to receive standard chemotherapy with or without bevacizumab, with radiation therapy to all disease sites recommended after chemotherapy cycle 6. We retrospectively evaluated the impact of radiation therapy on survival in the mRMS cohort.

METHODS AND MATERIALS

Patients were grouped according to the radiation therapy they received: radical, partial, or none. Radical irradiation was defined as radiation therapy delivered to all disease sites, unless a site was completely surgically resected. Partial irradiation was defined as radiation therapy to ≥1, but not all, disease sites. Landmark analysis excluded patients with an event before day 221. Overall survival (OS) and event-free survival (EFS) were modeled using Cox proportional hazards models.

RESULTS

Of 102 patients with mRMS, 97 were included in the analysis for OS and 85 for EFS. Overall, 27 patients received radical irradiation, 46 partial irradiation, and 24 no irradiation. EFS was not significantly different among patient groups after adjustment for prognostic factors (hazard ratio [HR] = 0.520; P = .054 for any vs no irradiation). Radiation therapy was associated with improved OS compared with no radiation therapy (adjusted HR = 0.249; P = .00025), with OS being greater for radical versus partial irradiation (HR = 0.245; P = .039). The 3-year OS rate was 84%, 54%, and 23% for patients receiving radical, partial, and no irradiation, respectively. Radical treatment (surgery, irradiation, or both) of the primary site improved EFS and OS compared with no treatment.

CONCLUSIONS

These findings demonstrate variability in the application of radiation therapy for mRMS and support the routine use of radical treatment to the primary site. Radical irradiation to metastatic sites may further improve OS. The burden of such treatment should be balanced against prognosis; further studies are needed.

Non-parameningeal head and neck rhabdomyosarcoma in children, adolescents, and young adults: Experience of the European paediatric Soft tissue sarcoma Study Group (EpSSG) - RMS2005 study

BACKGROUND/OBJECTIVES

The primary aim of this study was to analyse and evaluate the impact of different local treatments on the pattern of relapse in children with primary head and neck non-parameningeal (HNnPM) rhabdomyosarcoma (RMS), treated in the European paediatric Soft tissue sarcoma Study Group (EpSSG) RMS2005 study. The secondary aim was to assess whether current risk stratification is valid for this specific site.

DESIGN/METHODS

This study includes all patients with localised HNnPM RMS enrolled in the RMS2005 study between 2005 and 2016. Treatment comprised chemotherapy adapted to risk group, with local surgery and/or radiation therapy. The main outcome measures were event-free survival (EFS) and overall survival (OS).

RESULTS

A total of 165 patients were identified; the median age was 6.4 years (range, 0.1-25). The most common tumour sites were cheek/chin (22%) and nasal ala/nasolabial fold (20%). Histology was unfavourable for 40%, and regional nodal involvement present in 26%. Local therapy included surgery (58%) and/or radiotherapy (72%) to primary tumour and/or regional lymph nodes. After a median follow-up of 66 months (range, 6-158), 42 patients experienced an event, and 17 are still alive. Tumour events were frequent in oral primary (36%), parotid site (26%), cheek/chin (24%), and nasal ala/nasolabial fold (24%) and included locoregional failure in 84% of cases. The 5-year EFS and OS were 75% (95% confidence interval [CI]: 67.3-81.2) and 84.9% (95% CI: 77.5-89.7), respectively. Favourable histology was associated with a better EFS (82.3% versus 64.6%; p = 0.02) and nodal spread with a worse OS (88.6% versus 76.1%; p = 0.04). Different sublocations within the HNnPM primary did not have significant impact on outcome.

CONCLUSION

Locoregional relapse/progression is the main tumour failure event in this site. Despite frequent unfavourable risk factors, HNnPM RMS remains a favourable location in the context of a risk-adapted strategy.

Population-based survival of pediatric rhabdomyosarcoma of the head and neck over four decades

OBJECTIVES

Clinical trials have reported increases in the survival of pediatric rhabdomyosarcoma (RMS) from 25% in 1970 to 73% in 2001. The purpose of this study was to examine whether survival of pediatric patients with RMS of the head and neck improved at the US population level.

METHODS

A population-based cohort of patients with rhabdomyosarcoma of the head and neck aged 0-19 years in the Surveillance, Epidemiology, and End Results (SEER) registry from 1973 to 2013 was queried. The cumulative incidence competing risks (CICR) method was used to estimate risk and survival trends.

RESULTS

718 cases were identified for analysis. Survival rates at 1-, 5-, and 10-years after diagnosis were 91.2%, 73.2%, and 69.4% respectively. Survival rates at 1 year after diagnosis increased from 82.6% to 93.1% during the study period. In the subdistributional hazard analysis, there was a significantly improved disease-specific risk of death in the first year after diagnosis. Overall risk of death did not improve significantly. Favorable prognostic factors included age <10 years at diagnosis, smaller tumor size, absence of distant metastasis, localized tumors, earlier stage at presentation, grossly complete surgical resection, and embryonal or botryoid histology.

CONCLUSIONS

Disease-specific survival in the first year following diagnosis improved, but the change in overall survival at the population level was not statistically significant. These findings should be interpreted in light of the inclusion of patients with distant metastasis at diagnosis, who have poor prognoses, together with the limited statistical power afforded in studies of rare diseases.

Head and neck tumors in children and adolescents: Impact of a multidisciplinary tumor board

INTRODUCTION

Cancer treatment in France is based on Multidisciplinary Tumor Board (MTB). In the Ile-de-France region (IDF), which includes 12 million inhabitants from Paris and the surrounding area, pediatric tumors of head and neck are discussed since 2013 in a dedicated Interregional Pediatric Multicentric MTB (IPMTB). The purpose of this study is to analyze the impact of the IDF head and neck IPMTB on the management of these tumors, 5 years after their implementation.

MATERIALS AND METHODS

Retrospective study of all patient files presented in the IPMTB for a benign or malignant head-and-neck tumor, between 2013 and 2018.

RESULTS

A total of 679 discussions were analyzed representing 428 patients. Median age was 7.5 years (range: 0-31 years). Malignant tumors represented 71% of cases, including 36% of rhabdomyosarcoma. Overall, 12% percent of the cases discussed came from centers outside of IDF. All meetings complied with multidisciplinary criteria required by French law. Proposals made during the IPMTB were followed in 86% of cases. Among the 251 proposals made by the referring teams prior to the IPMTB, 29% were secondarily modified after being discussed in the IPMTB.

CONCLUSION

Thanks to their multidisciplinarity, high number of cases discussed and usual respect of their proposals, the IPMTB have made it possible to improve the coordination between all specialties involved in the patient's management, to apply the most recent and scientifically validated protocols, and to share the knowledge of different teams concerning the management of particularly rare tumors.

Locoregional Control and Survival in Children, Adolescents, and Young Adults With Localized Head and Neck Alveolar Rhabdomyosarcoma-The French Experience

INTRODUCTION

The head and neck (HN) are the most frequent sites of pediatric rhabdomyosarcoma (RMS). Alveolar RMS (ARMS) represents ~20% of all RMS cases and frequently spread to lymph nodes (LNs). The aim was to report locoregional control, event-free survival (EFS), and overall survival (OS), according to clinical and pathological features, LN staging, and treatment modalities.

METHODS

The study included all patients prospectively enrolled in EpSSG RMS 2005 study under 21 years of age with localized HN ARMS and diagnosed between 2005 and 2016 in France. Medical data including imaging, surgical report, and radiation therapy planes were analyzed.

RESULTS

Forty-eight patients (median age 6 years; range 4 months-21 years), corresponding to 30 parameningeal and 18 non-parameningeal ARMS, were included. There were 33 boys (69%). Tumor locations included the following: orbit (n = 7) among which four cases had bone erosion, paranasal sinuses and nasal cavity (n = 16), deep facial spaces (n = 10), nasolabial fold (n = 8), and other non-parameningeal HN sites (n = 7). A fusion transcript of PAX3-FOXO1 or PAX7-FOXO1 was expressed in 33 of the 45 cases (73%) with molecular analysis. At diagnosis, 10 patients had primary resection of the primary tumor (PRPT) (none with microscopic complete resection) and 9 had LN staging. After induction chemotherapy, 26 patients (54%) had secondary resection of the primary tumor (SRPT) and 13 patients (27%) had cervical LN dissection. A total of 43 patients (90%) were treated with radiation therapy.With a median follow-up of 7 years (range 2-13 years), 5-year OS and EFS were 78% (95% CI, 63-88%) and 66% (95% CI, 51-78%), respectively. We observed 16 events (10 deaths): 4 local, 4 regional, 1 local and regional, and 7 metastatic. In univariate analysis, OS was only superior for patients under 10 years of age (p = 0.002), while FOXO1-negative ARMS, SRPT for parameningeal ARMS, and LN surgery were associated with significantly better EFS.

CONCLUSION

Our study confirms a better outcome for fusion-negative ARMS and ARMS in children under 10 years. Moreover, LN surgery and SRPT of parameningeal tumor may improve EFS of ARMS. Larger studies are needed to confirm our findings.

Treatment of rhabdomyosarcoma in children and adolescent from four low health expenditures average rates countries

Background

Survival of children with cancer in Eastern and Central Europe is 10–20% lower than in high income European countries. We evaluated outcome of children and adolescents with rhabdomyosarcoma (RMS) in Slovenia, Croatia, Slovakia and in Romania.

Patients and methods

We retrospectively analysed event-free survival (EFS) and overall survival (OS) for all patients treated in Slovenia and Croatia. Slovakia included patients from two centers, representing half of expected cases. Romania included patients from single institution, representing only 10% of expected patients. Joint database for analysis was established.

Results

One hundred seventy-eight children and adolescent with RMS diagnosed from January 2000 to December 2015 were included. Mean patient age at diagnosis was 7.7 years, one third was older than 10 years. Twenty-five percent had alveolar histology and 72% unfavorable location. Higher than expected proportion of patients had nodal involvement (24%) or metastatic disease (27%). All patients received systemic chemotherapy, 57% had radiotherapy and 63% surgery as local control. Kaplan- Meier estimates for 5-year EFS and OS were 50.7% and 59.6%, respectively. Five-year OS for patients with localised disease was 72% compared to 24% for metastatic disease.

Conclusions

Children with RMS treated in Eastern and Central Europe have inferior outcome compared to their counterparts treated in high income European countries. Active participation of low health expenditures average rates (LHEAR) countries in international clinical trials may improve outcome of paediatric oncology patients.

Radiation therapy is an important factor to improve survival in pediatric patients with head and neck rhabdomyosarcoma by enhancing local control: a historical cohort study from a single center

Background

The purpose of this study is to analyze the influence of radiation therapy on survival in a historical cohort of 56 pediatric patients with head and neck rhabdomyosarcoma.

Methods

A historical cohort of 56 pediatric patients with head and neck rhabdomyosarcoma from June 1st, 2013 to June 30th, 2019 was chosen. Clinical data and follow up results were collected including all diagnosis, treatment and prognosis information. Overall survival (OS) and event free survival (EFS) as time-to-event distributions were estimated with Kaplan-Meier method, and univariate analysis was performed with log rank test to detect differences between groups. Multivariate analysis was performed to explore the risk factors for survival with Cox proportional hazard model.

Results

The media follow up time of all 56 patients was 31.8 months (range 3.5–74.6 months). There were 26 events during follow up, including 14 disease progressions and 12 relapses. The estimated 5-year OS of all patients was 69.9%, and the estimated 5-year EFS was 48.8%. Patients with radiation therapy as a component of the initial treatment plan had better 5-year OS and EFS compared with those without radiation therapy (OS 80.3% vs. 49.7%, p = 0.003 and EFS 63.9% vs. 21.9%, p < 0.001). In patients with events, those who received salvage radiation therapy had better 5-year OS compared with those who didn’t (OS 66.0% vs. 31.2%, p = 0.033). On multivariate analysis, tumor size > 5 cm and non-initial radiation therapy were independent risk factors for OS in all patients, non-initial radiation therapy was an independent risk factor for EFS in all patients, and tumor size > 5 cm was an independent risk factor for OS in patients with events.

Conclusions

Radiation therapy as a component of initial treatment can improve the OS and EFS in pediatric head and neck rhabdomyosarcoma patients by enhancing local control, and non-initial radiation therapy is an independent risk factor for OS and EFS. Salvage radiation therapy still can improve OS in patients with disease progression and relapse. Tumor size > 5 cm is an independent risk factor for OS in pediatric HNRMS patients with or without disease progression/relapse.

An unresolved issue in rhabdomyosarcoma treatment: The duration of chemotherapy

Clinical trials have tested different chemotherapy regimens to improve outcome for patients with rhabdomyosarcoma (RMS), but therapy duration has never been explicitly evaluated. North American trials evolved from longer (104 weeks) to shorter duration (24-42 weeks). In Europe, treatment duration similarly evolved from 35 to 48 to 22 weeks for lower risk patients and from 56 to 72 to 27 weeks for higher risk patients. There was no evidence that chemotherapy duration influenced outcome over time. The recent RMS2005 trial showed an improved survival with the addition of 24 weeks of low-dose chemotherapy. Treatment duration remains a question to be addressed in future trials.

Outcome and Patterns of Relapse in Childhood Parameningeal Rhabdomyosarcoma Treated With Proton Beam Therapy

PURPOSE

The standard of care of childhood parameningeal rhabdomyosarcoma (pRMS) is chemotherapy and local radiation therapy. Protons are increasingly being used to decrease late effects. The aim of the present study is to analyze the pattern of relapse and the correlation with dosimetric factors in pRMS treated with proton therapy.

METHODS AND MATERIALS

This retrospective evaluation includes children treated in our institution for pRMS. Information on demographics, treatment, tumor characteristics, and toxicities and outcome was prospectively collected within the in-house registry. For patients presenting with local relapse, a fusion of the dosimetry with magnetic resonance imaging displaying site and geometry of recurrence was performed.

RESULTS

Median follow-up time was 2.9 years (0.5-4.7). Forty-six patients were identified in our institution between July 2013 and November 2017. Main characteristics of patients were as follows: 56.5% male, median age 5.1 years (1.3-17.5), 39.1% alveolar histology, 26.1%, 52.2%, 8.7%, and 13% patients with subgroup risk classification D, E/F/G, H, or metastatic, respectively, median total prescribed dose 55.8 Gy (50.4-56.4). Estimated 2-year local control, metastasis-free survival, event-free survival, and overall survival were 83.8%, 87.8%, 76.9%, and 88.9%, respectively. No acute or late local toxicity exceeding grade 3 was observed. Risk-group was identified as prognostic factor for metastasis-free survival in univariate analysis but not in multivariate analysis (trend: P = .09). In this cohort, dosimetric factors did not correlate with outcome. Isolated local failure happened in 5 of the 11 relapses. Local relapses were matched with dosimetry for 6 patients: 4 of them occurred in the high dose volume and 2 in the intermediate or low dose volume.

CONCLUSIONS

Proton therapy was effective and well feasible even in a critical cohort. Still, local relapse within the target volume of the radiation therapy remains an important issue in pRMS and new treatment strategies are needed.

125 I interstitial brachytherapy in management of pediatric skull base tumors

BACKGROUND

The purpose of this study was to present our preliminary assessment of the safety and efficacy of ¹²⁵ I interstitial brachytherapy (IBT) in the management of pediatric skull base tumors.

METHODS

Thirty pediatric patients with skull base tumors treated with ¹²⁵ I IBT from April 2007 to May 2017 were included in this study. The probabilities of local control (LC) and overall survival (OS) were calculated by the Kaplan-Meier method.

RESULTS

The one- and two-year LC rates were 96.7% and 74.8%, respectively. The one- and two-year OS rates were 93.3% and 72.2%, respectively. No severe acute toxicity was observed. Severe late toxicities were observed in one (3.33%) of 30 patients.

CONCLUSION

¹²⁵ I IBT is effective and safe in the management of pediatric skull base tumors, with satisfactory cosmetic and functional outcomes.

Evolving Radiotherapy Techniques in Paediatric Oncology

AIMS

Childhood cancer is rare and survival of childhood cancer has increased up to 80% at 5 years after diagnosis. Radiotherapy is an important element of the multimodal treatment concept. However, due to growing tissue, children are particularly sensitive to radiation-related side-effects and the induction of secondary malignancies. However, radiotherapy techniques have continuously progressed. In addition, modern treatment concepts have been improved in order to minimise long-term effects. Today, radiotherapy is used for various tumour types in childhood, such as sarcomas and tumours of the central nervous system.

MATERIALS AND METHODS

External beam therapy with either photons or protons and brachytherapy are predominantly used for the treatment of childhood tumours. Technical developments and features, as well as clinical outcomes, for several tumour entities are presented.

RESULTS

The development of radiotherapy techniques, as well as risk-adapted therapy concepts, resulted in promising outcome regarding tumour control, survival and therapy-related side-effects. It is assumed that proton therapy will be increasingly used for treating children in the future. However, more data have to be collected through multi-institutional registries in order to strengthen the evidence.

CONCLUSION

The development of radiotherapy techniques is beneficial for children in terms of reducing dose exposure. As compared with other modern and highly conformal techniques, particularly proton therapy may achieve high survival rates and tumour control rates while decreasing the risk for side-effects. However, clinical evidence for modern radiotherapy techniques is still limited today. An optimal patient triaging with the selection of the most appropriate radiation technique for each individual patient will be an important goal for the future.

Dental and craniofacial alterations in long-term survivors of childhood head and neck rhabdomyosarcoma

OBJECTIVE

Rhabdomyosarcoma (RMS) represents the most common soft tissue sarcoma that affects children. Treatment involves chemoradiotherapy. This study aimed at evaluating the long-term alterations to teeth and cranial bones in children, teenagers, and young adults after oncologic treatment.

STUDY DESIGN

We conducted a cross-sectional study of patients undergoing treatment for head and neck RMS between 1988 and 2011. We evaluated demographic, clinical, and treatment data and performed panoramic radiography, cephalometry, and photography.

RESULTS

We evaluated 27 long-term survivors, most of whom had been treated between ages 0 to 5 years (51.9%). The total radiation dose applied was 50.4 Gy, and the chemotherapy combination included vincristine, actinomycin D, and cyclophosphamide in 51.9% of the cases. We observed 603 dental alterations, among which 377 (62.7%) occurred in patients ages 0 to 5 years, and root shortening was the most frequent alteration observed (24.2%). With regard to facial bones, 74% of the patients had some level of facial asymmetry, 70.4% had reduced facial depth, 48.4% had mandibles of short size, and 77.8% had reduced facial height.

CONCLUSIONS

Children submitted to RMS treatment involving chemotherapy and radiotherapy displayed significant dental and craniofacial alterations, especially when treatment occurred between ages 0 and 5 years.

Excessive Treatment Failures in Patients With Parameningeal Rhabdomyosarcoma With Reduced-dose Cyclophosphamide and Delayed Radiotherapy

Pediatric patients with parameningeal rhabdomyosarcoma and high-risk features are recommended to receive radiotherapy at initiation of protocol therapy due to concerns about the increased risk of local and leptomeningeal failure from treatment delay. We report our early experience on a multi-institutional prospective trial incorporating delayed primary site radiation and reduced dose cyclophosphamide in all patients with parameningeal tumors. We observed an excessive number of locoregional treatment failures following this approach and have subsequently amended our trial to move radiation therapy upfront for those patients with high-risk features. We suggest that investigators should be vigilant for treatment failure given our early prospective experience with delayed radiotherapy and reduced dose cyclophosphamide.

Proton therapy for pediatric malignancies: Fact, figures and costs. A joint consensus statement from the pediatric subcommittee of PTCOG, PROS and EPTN

Radiotherapy plays an important role in the management of childhood cancer, with the primary aim of achieving the highest likelihood of cure with the lowest risk of radiation-induced morbidity. Proton therapy (PT) provides an undisputable advantage by reducing the radiation 'bath' dose delivered to non-target structures/volume while optimally covering the tumor with tumoricidal dose. This treatment modality comes, however, with an additional costs compared to conventional radiotherapy that could put substantial financial pressure to the health care systems with societal implications. In this review we assess the data available to the oncology community of PT delivered to children with cancer, discuss on the urgency to develop high-quality data. Additionally, we look at the advantage of combining systemic agents with protons and look at the cost-effectiveness data published so far.

Rhabdomyosarcoma of the Head and Neck: A Multimodal Approach

Head and neck rhabdomyosarcoma (HNRMS) is a uniquely challenging site to treat given the young patient age and critical anatomy of the head and neck region. We review the characteristics, management, and future directions in the treatment of HNRMS. Most patients who present with HNRMS have unresectable disease due to functional and/or cosmetic constraints. However, surgical resection and brachytherapy serve a critical role in select patients. The treatment paradigm for the majority of patients with HNRMS consists of definitive chemotherapy and radiation therapy. As the incidence of late toxicities increases with improved survival, modern efforts must focus on ways to decrease long-term morbidity. We recommend a multimodal approach emphasizing the preservation of form and function for the treatment of HNRMS.

Facial asymmetry in head and neck rhabdomyosarcoma survivors

INTRODUCTION

Radiotherapy is essential for achieving and maintaining local control in head and neck rhabdomyosarcoma (HNRMS) patients. However, radiotherapy may cause outgrowth disturbances of facial bone and soft tissue, resulting in facial asymmetry. The aim of this study was to develop a method to visualize and measure facial asymmetry in HNRMS survivors using three-dimensional (3D) imaging techniques.

METHODS

Facial deformity was evaluated in a multidisciplinary clinical assessment of 75 HNRMS survivors, treated with external beam radiotherapy (EBRT, n = 26) or Ablative surgery, MOulage brachytherapy, and REconstruction (AMORE, n = 49). Individual facial asymmetry was measured using 3D photogrammetry and expressed in a raw asymmetry index and a normalized sex-age-ethnicity-matched asymmetry signature weight. Facial asymmetry was also compared between British and Dutch controls and between survivors and their matched controls.

RESULTS

Facial asymmetry was more pronounced with increasing age (P < 0.01) in British controls compared with Dutch controls (P = 0.04). Survivors developed more facial asymmetry than matched controls (P < 0.001). The clinical assessment of facial deformity correlated with the raw asymmetry index (r = 0.60, P < 0.001).

DISCUSSION

3D imaging can be used for objective measurement of facial asymmetry in HNRMS survivors. The raw asymmetry index correlated with a clinical assessment of facial deformity. Comparisons between treatment groups seemed inappropriate given the differences in facial asymmetry between British and Dutch controls. In future studies, pretreatment images could act as matched controls for posttreatment evaluation.

Adherence to Treatment, Response and Patterns of Failure in Pediatric Parameningeal Rhabdomyosarcoma: Experience From a Tertiary Cancer Care Center From India

The study was aimed at evaluating adherence to treatment protocol and outcome in pediatric parameningeal rhabdomyosarcoma (PM-RMS). We analyzed the characteristics, treatment administered, outcomes and patterns of failure of pediatric PM-RMS, who were treated with multimodality therapy between January 2005 and December 2013.Univariate and multivariate analysis (MVA) was completed to evaluate the impact of various prognostic factors. Thirty-seven patients were treated at our institution. Majority of them had the primary disease in paranasal sinuses (n=13). Majority of the patients belonged to group III (n=30) and stage III (n=24). The overall response rate to treatment was 52.5% (n=21). At a mean follow-up of 19.1 months, 23 patients developed disease progression. The actuarial rates of failure-free survival and overall survival (OS) at 2 years were 40% and 67.5%, respectively. Patients who received >20 weeks of intended chemotherapy schedule (P=0.02) and had complete response to first-line treatment (P=0.0004) were found to have superior failure-free survival on MVA. Complete response was the lone determinant of superior OS on MVA (P=0.006). Majority of patients with PM-RMS present with advanced stage disease. Response to first-line treatment is a significant predictor of superior progression-free survival and OS in these patients.

Pencil Beam Scanning Proton Therapy for Pediatric Parameningeal Rhabdomyosarcomas: Clinical Outcome of Patients Treated at the Paul Scherrer Institute

BACKGROUND

Parameningeal rhabdomyosarcomas (PM-RMSs) represent approximately 25% of all rhabdomyosarcoma (RMS) cases. These tumors are associated with early recurrence and poor prognosis. This study assessed the clinical outcome and late toxicity of pencil beam scanning (PBS) proton therapy (PT) in the treatment of children with PM-RMS.

PROCEDURES

Thirty-nine children with PM-RMS received neoadjuvant chemotherapy followed by PBS-PT at the Paul Scherrer Institute, with concomitant chemotherapy. The median age was 5.8 years (range, 1.2-16.1). Due to young age, 25 patients (64%) required general anesthesia during PT. The median time from the start of chemotherapy to PT was 13 weeks (range, 3-23 weeks). Median prescription dose was 54 Gy (relative biologic effectiveness, RBE).

RESULTS

With a mean follow-up of 41 months (range, 9-106 months), 10 patients failed. The actuarial 5-year progression-free survival (PFS) was 72% (95% CI, 67-94%) and the 5-year overall survival was 73% (95% CI, 69-96%). On univariate analysis, a delay in the initiation of PT (>13 weeks) was a significant detrimental factor for PFS. Three (8%) patients presented with grade 3 radiation-induced toxicity. The estimated actuarial 5-year toxicity ≥grade 3 free survival was 95% (95% CI, 94-96%).

CONCLUSIONS

Our data contribute to the growing body of evidence demonstrating the safety and effectiveness of PT for pediatric patients with PM-RMS. These preliminary results are encouraging and in line with other combined proton-photon and photons series; observed toxicity was acceptable.

The impact of radiotherapy on clinical outcomes in parameningeal rhabdomyosarcoma

PURPOSE

Radiotherapy (RT) is considered a mainstay of treatment in parameningeal rhabdomyosarcoma (PM-RMS). We aim to determine the treatment outcomes and prognostic factors for PM-RMS patients who treated with RT. In addition, we tried to evaluate the adequate dose and timing of RT.

MATERIALS AND METHODS

Twenty-two patients with PM-RMS from 1995 to 2013 were evaluated. Seven patients had intracranial extension (ICE) and 17 patients had skull base bony erosion (SBBE). Five patients showed distant metastases at the time of diagnosis. All patients underwent chemotherapy and RT. The median radiation dose was 50.4 Gy (range, 40.0 to 56.0 Gy).

RESULTS

The median follow-up was 28.7 months. Twelve patients (54.5%) experienced failure after treatment; 4 local, 2 regional, and 6 distant failures. The 5-year local control (LC) and overall survival (OS) were 77.7% and 38.5%, respectively. The 5-year OS rate was 50.8% for patients without distant metastases and 0% for patients with metastases (p < 0.001). Radiation dose (<50 Gy vs. ≥50 Gy) did not compromise the LC (p = 0.645). However, LC was affected by ICE (p = 0.031). Delayed administration (>22 weeks) of RT was related to a higher rate of local failure (40.0%).

CONCLUSION

RT resulted in a higher rate of local control in PM-RMS. However, it was not extended to survival outcome. A more effective treatment for PM-RMS is warranted.

A clinicopathologic study of head and neck rhabdomyosarcomas showing FOXO1 fusion-positive alveolar and MYOD1-mutant sclerosing are associated with unfavorable outcome

BACKGROUND

Based on their distinctive histologic and genetic features, the latest WHO classification of soft tissue tumors includes four pathologic variants of rhabdomyosarcoma (RMS): embryonal (ERMS), alveolar (ARMS), spindle cell-sclerosing (SRMS-ScRMS) and pleomorphic RMS. The aim of this study focused on a detailed clinicopathologic and survival analysis of head and neck RMS (HNRMS) using the latest pathologic and molecular criteria reflecting this new subclassification in a large cohort.

PATIENTS AND METHODS

Patients managed for HNRMS in our institution (1996-2015) were analyzed. The presence of a FOXO1 fusion was required for the classification of ARMS. MYOD1 mutations in SRMS-ScRMS were tested when material available. Univariate and multivariate analyses were performed to evaluate variables related to overall survival (OS).

RESULTS

Ninety-nine HNRMS patients (52 males and 47 females, mean of 16years) were included in the study after pathologic re-review. The most common location was parameningeal (PM) (n=64), followed by non-orbital/non-PM (n=25) and orbital (n=10). There were 53 ERMS, 33 fusion-positive ARMS and 13 SRMS-ScRMS [SRMS (8); ScRMS (5)]. The 5-year OS rate for ERMS patients was significantly higher (82%) compared to ARMS (53%) and SRMS-ScRMS (50%) [SRMS (75%); ScRMS (30%)]. Univariate analysis showed that survival was dependent on histology (P=0.012), tumor size >5cm (P<0.001), regional lymph node involvement (P=0.002), metastasis at initial presentation (P<0.001), stage (P<0.001), and recurrence (P=0.002). Multivariate analysis confirmed histologic subtype to be significant (P=0.043).

CONCLUSION

Our findings reinforce that HNRMS is a heterogenous disease with ARMS and SRMS-ScRMS having an equally unfavorable outcome.

Prognostic Factors for Outcome in Localized Extremity Rhabdomyosarcoma. Pooled Analysis from Four International Cooperative Groups

BACKGROUND

Extremity rhabdomyosarcomas do not always show satisfactory outcomes. We analyzed data from 643 patients treated in 14 studies conducted by European and North American groups between 1983 and 2004 to identify factors predictive of outcome.

PROCEDURE

Clinical factors, including age; histology; site of primary (hand and foot vs. other); size; invasiveness (T stage); nodal involvement (N stage); and treatment factors, including post-surgical group; chemotherapy type and duration; radiotherapy; and treatment (before or after 1995); were evaluated for impact on overall survival (OS).

RESULTS

5-year OS were 67% (se 1.8). Multivariate analysis showed that lower OS correlated with age >3 years, T2 and N1 stage, incomplete initial surgery, treatment before 1995, and European cooperative group treatment. Patients with gross residual disease after initial incomplete resection/biopsy had similar outcomes in both continental groups. The better global survival of patients treated in American studies was accounted for by differences in outcome in the subset of those with grossly resected tumors (OS 86% [se 3] for COG patients vs. 68% [se 4] for European patients (P = 0.004)). When excluding chemotherapy duration from the model, analysis in this subset of patients showed that cooperative group (P = 0.001), site (P = 0.001), and T stage (P = 0.05) were all significant. However, after adding duration of chemotherapy (≥27 weeks) to the model, only primary site remained significant (P = 0.006).

CONCLUSION

This meta-analysis confirms the role of many established prognostic factors but identifies for the first time that chemotherapy duration may have an impact on outcome in patients with grossly resected tumors.

A Patient-Derived Xenograft Model of Parameningeal Embryonal Rhabdomyosarcoma for Preclinical Studies

Embryonal rhabdomyosarcoma (eRMS) is one of the most common soft tissue sarcomas in children and adolescents. Parameningeal eRMS is a variant that is often more difficult to treat than eRMS occurring at other sites. A 14-year-old female with persistent headaches and rapid weight loss was diagnosed with parameningeal eRMS. She progressed and died despite chemotherapy with vincristine, actinomycin-D, and cyclophosphamide plus 50.4 Gy radiation therapy to the primary tumor site. Tumor specimens were acquired by rapid autopsy and tumor tissue was transplanted into immunodeficient mice to create a patient-derived xenograft (PDX) animal model. As autopsy specimens had an ALK R1181C mutation, PDX tumor bearing animals were treated with the pan-kinase inhibitor lestaurtinib but demonstrated no decrease in tumor growth, suggesting that single agent kinase inhibitor therapy may be insufficient in similar cases. This unique parameningeal eRMS PDX model is publicly available for preclinical study.

Proton therapy for sarcomas

Sarcomas are a heterogeneous group of tumors that can occur in a wide array of anatomic sites and age ranges with varying histologies. Proton beam therapy, as compared with advanced x-ray radiation therapy techniques, can substantially lower dose to nontarget tissues. This dosimetric advantage can potentially allow for improvement of the therapeutic ratio in the treatment of many of the sarcomas by either increasing the local control, via increased dose to the target, or by decreasing the normal tissue complications, via lowered dose to the avoidance structures. This article reviews the key dosimetric studies and clinical outcomes published to date documenting the potential role proton beam therapy may play in the treatment of sarcomas.

Recent advances in understanding and managing rhabdomyosarcoma

Rhabdomyosarcoma is the most common childhood soft tissue sarcoma and the fourth most common pediatric solid tumor. For most patients, treatment consists of a multimodality approach, including chemotherapy, surgery, and/or radiotherapy. To guide treatment, patients with rhabdomyosarcoma are risk stratified based on a number of factors. These factors include clinical group, which depends largely on the extent of resection and nodal involvement, and stage, which takes into account tumor size, invasion, nodal involvement, and disease site. Histology of the tumor and age at diagnosis are also factored into risk stratification. Recent advances in understanding the biology of the disease have allowed for the further sub-classification of rhabdomyosarcoma. In addition, elucidation of additional clinical features associated with poor prognosis has allowed for better understanding of risk and provides more clarity regarding those patients who require more intensive therapy. Many areas of active investigation are ongoing, including the following: further delineation of the biological underpinnings of the various disease subtypes with the possibility of molecularly targeted therapy; a better understanding of clinical risk factors, including the evaluation and management of potentially involved lymph nodes; determination of the appropriate role of post-treatment imaging and assessment of response to therapy; and incorporation of advanced radiotherapeutic techniques, including conformal intensity-modulated photon and proton therapy.

Local failure in parameningeal rhabdomyosarcoma correlates with poor response to induction chemotherapy

BACKGROUND

Local control remains a challenge in pediatric parameningeal rhabdomyosarcoma (PM-RMS), and survival after local failure (LF) is poor. Identifying patients with a high risk of LF is of great interest to clinicians. In this study, we examined whether tumor response to induction chemotherapy (CT) could predict LF in embryonal PM-RMS.

METHODS

We identified 24 patients with embryonal PM-RMS, age 2 to 18 years, with complete magnetic resonance imaging and gross residual disease after surgical resection. All patients received proton radiation therapy (RT), median dose 50.4 GyRBE (50.4-55.8 GyRBE). Tumor size was measured before initial CT and before RT.

RESULTS

With a median follow-up time of 4.1 years for survivors, LF was seen in 9 patients (37.5%). The median time from the initiation of CT to the start of RT was 4.8 weeks. Patients with LF had a similar initial (pre-CT) tumor volume compared with patients with local controlled (LC) (54 cm(3) vs 43 cm(3), P=.9) but a greater median volume before RT (pre-RT) (40 cm(3) vs 7 cm(3), P=.009) and a smaller median relative percent volume reduction (RPVR) in tumor size (0.4% vs 78%, P<.001). Older age (P=.05), larger pre-RT tumor volume (P=.03), and smaller RPVR (P=.003) were significantly associated with actuarial LF on univariate Cox analysis.

CONCLUSIONS

Poor response to induction CT appears to be associated with an increased risk of LF in pediatric embryonal PM-RMS.

Orbital rhabdomyosarcoma in children: a favorable primary suitable for a less-invasive treatment strategy

BACKGROUND

Orbital rhabdomyosarcoma (ORMS) treatment is based on combination chemotherapy associated with best local therapy, sometimes surgery but more often radiation therapy. A retrospective single-center analysis was conducted to more clearly define the long-term outcome of patients with ORMS, to identify patients in whom aggressive first-line local therapy can be avoided.

POPULATION

A total of 95 patients with localized parameningeal (PM) or nonparameningeal (NPM) ORMS, treated at the Institut Curie between 1975 and 2010, were analyzed.

RESULTS

Median age at diagnosis was 6 years (range, 8 mo to 19.5 y), and median follow-up was 8.5 years (range, 7 mo to 24 y). A total of 25 patients presented PM extension. Radiation therapy was part of primary therapy for 78 patients. Five-year event-free survival and overall survival rates were 65.4%±5.2% and 85.6%±3.9%, respectively. On multivariate analysis, initial tumor size was identified as a significant prognostic factor. Event-free survival was similar for PM and NPM tumors (60.3%±10.4% vs. 62.7%±5.9%, P=0.57), whereas there was a trend for overall survival to be better for NPM tumors (90%±3.9% vs. 72.7%±9.6%, P=0.07).

CONCLUSIONS

Localized ORMS has a favorable outcome despite the current trend toward less aggressive and more limited indications of local therapy. Patients with a favorable pattern of strictly ORMS can be treated without first-line radiation therapy.