Worse Outcomes for Head and Neck Rhabdomyosarcoma Secondary to Reduced-Dose Cyclophosphamide

Multimodality Treatment Outcome in Adult Patients with Head and Neck Rhabdomyosarcoma

OBJECTIVE(S)

Head and neck rhabdomyosarcoma (HNRMS) is a rare malignant tumor in adults. No standard treatment for adults with HNRMS currently exists.

METHODS

A retrospective study of 72 newly diagnosed consecutive adult patients with HNRMS was conducted at one institution between November 2010 and April 2023. The log-rank tests were used to compare the differences in survival between treatment groups, and overall survival (OS), local recurrence-free survival (LRFS), progression-free survival (PFS), and distant metastasis-free survival (DMFS) were calculated using the Kaplan-Meier method. We used restricted cubic spline models fitted for Cox proportional hazards models to determine the association between chemotherapy cycles/radiotherapy dose and mortality.

RESULTS

The 2-year OS, PFS, LRFS, and DMFS rates for the entire cohort were 51.0%, 39.2%, 44.3%, and 47.3%, respectively. Radiotherapy significantly improved the OS (p < 0.01), PFS (p < 0.01), LRFS (p < 0.01), and DMFS (p < 0.01). Surgery had no effect on OS (49.3% vs. 53.0%, p = 0.62), PFS (36.9% vs. 41.8%, p = 0.31), LRFS (41.6% vs. 47.4%, p = 0.27), or DMFS (44.4% vs. 50.2%, p = 0.43). The restricted cubic spline showed that eight (HR = 1.002, 95% CI: 0.996-1.007) cycles of chemotherapy and 62.5Gy radiation therapy resulted in the lowest mortality.

CONCLUSION

For HNRMS, eight cycles of chemotherapy and 62.5Gy of radiation might be sufficient. Poor response to chemotherapy predicted an extreme worse outcome. Surgery played a limited role in the treatment.

LEVEL OF EVIDENCE

3 Laryngoscope, 135:2022-2029, 2025.

Parameningeal Rhabdomyosarcoma-Clinical Profile, Outcomes, and Prognostic Factors in Children Treated at a Single Center Over a Decade

BACKGROUND

Parameningeal rhabdomyosarcomas (PM-RMS) in children is challenging to treat. While a 10-year event-free survival (EFS) of 62% has been reported from high-middle income countries (HMICs) for localized disease, data is limited from low-middle income countries (LMICs). We studied the clinical profile, outcomes, and prognostic factors in PM-RMS.

MATERIALS AND METHODS

Children aged 15 years or younger with PM-RMS treated on a uniform chemotherapy protocol from January 2013 to December 2021 were retrospectively analyzed. Local therapy at 10 to 12 weeks of induction was radiotherapy (RT)+/-surgery, where possible, with early RT for intracranial extension (ICE).

RESULTS

Seventy-six patients with a median age of 6.7 years (range: 3.2 to 15 y), male to female ratio of 1.8:1 formed the study cohort. Eleven patients (14.5%) had metastasis (lungs: 8, bone: 2, and bone marrow: 1) and ICE was seen in 46.1% (n=35). Twenty-five patients (49.0%) had alveolar histology with PAX3/7 positive in 17/59 (28.8%). The median tumor size (t size ) at baseline was 5.2 cm (range: 1.2 to 12.8 cm). Seventy-one patients received RT and 5 also underwent surgery. At a median follow-up of 65 months (range: 53 to 76 mo) 4 year EFS, OS of the whole cohort were 47.3% (95% CI: 34.8%-58.8%), 51.7% (95% CI: 38.0%-64.0%), respectively. Four-year EFS, OS of the localized and metastatic cohort were 54.7% (95% CI: 41.3%-68.1%), 56.0% (95% CI: 42.0%-70.0%), and 9.1% (95% CI: 0%-26.5%), 18.2% (95% CI: 0%-47.8%), respectively. Metastases (HR: 3.38, 95% CI: 1.57-7.26, and P =0.002), t size (HR: 1.17, 95% CI: 1.02-1.34, and P =0.026) were prognostic for survival on multivariate analysis.

CONCLUSIONS

Survival of children with localized PM-RMS in our study is relatively fair compared with the reported literature probably due to the application of RT in all despite higher proportion of larger tumors, unfavorable sites of primary, and intracranial extension. Identification of high-risk subsets and optimizing current treatment strategies, both systemic and local therapy may partly improve outcomes.

Radiation Therapy Dose Escalation Failed to Improve Local Control for Intermediate-Risk Rhabdomyosarcoma on ARST1431: A Report From the Children's Oncology Group

PURPOSE

To evaluate local failure (LF) rates for patients with intermediate-risk rhabdomyosarcoma treated on the Children's Oncology Group ARST1431 clinical trial, the first and largest international, phase 3 randomized study to use FOXO1 fusion status for risk stratification. To improve local control, radiation therapy (RT) dose was increased to 59.4 Gy for patients with tumors >5 cm and residual gross disease at the time of RT.

METHODS AND MATERIALS

For the 297 patients included, LF was defined as progression or relapse at the primary site. The rate of LF was calculated 3-years after enrollment.

RESULTS

LF for group 3, FOXO1 fusion-positive patients (n = 58) compared with fusion-negative patients (n = 175) was 10.7% versus 21.5%, respectively (P = .08). The LF rate for patients with tumors >5 cm at diagnosis (n = 180; 24.4%) was higher than that of patients with tumors ≤5 cm at diagnosis (n = 117; 9.8%), P = .002. The risk of LF for patients who received proton (n = 99) versus photon RT (n = 126) was not different (16.1% vs 15.9%, P = .8). For the 75 patients with tumors >5 cm at diagnosis and gross disease at the time of RT, the boost to 59.4 Gy did not improve the 3-year LF rate compared with that of patients who did not receive the boost (29.7% vs 16.1%, P = .6). For patients with group 3/4 disease, those who underwent delayed primary excision (n = 72) had a lower LF rate compared with those who had RT alone (n = 151) (5.8% vs 19.7%, P < .01).

CONCLUSIONS

On ARST1431, tumors >5 cm at diagnosis had poor local control despite dose escalation to 59.4 Gy. Proton and photon RT had equivalent local control. For select patients, delayed primary excision significantly improved local control.

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.

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.

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.

Radiation Therapy in the Treatment of Head and Neck Rhabdomyosarcoma

The use of radiation therapy is an important part of multimodality treatment for rhabdomyosarcoma. The specific doses, treatment volumes, and techniques used in radiation therapy can vary dramatically based upon a number of factors including location, tumor size, and molecular characteristics, resulting in complex decisions in treatment planning. This article reviews the principles of evaluation and management for head and neck rhabdomyosarcoma including a summary of the historical studies upon which current management is based.

Proton Radiotherapy to Reduce Late Complications in Childhood Head and Neck Cancers

In most childhood head and neck cancers, radiotherapy is an essential component of treatment; however, it can be associated with problematic long-term complications. Proton beam therapy is accepted as a preferred radiation modality in pediatric cancers to minimize the late radiation side effects. Given that childhood cancers are a rare and heterogeneous disease, the support for proton therapy comes from risk modeling and a limited number of cohort series. Here, we discuss the role of proton radiotherapy in pediatric head and neck cancers with a focus on reducing radiation toxicities. First, we compare the efficacy and expected toxicities in proton and photon radiotherapy for childhood cancers. Second, we review the benefit of proton radiotherapy in reducing acute and late radiation toxicities, including risks for secondary cancers, craniofacial development, vision, and cognition. Finally, we review the cost effectiveness for proton radiotherapy in pediatric head and neck cancers. This review highlights the benefits of particle radiotherapy for pediatric head and neck cancers to improve the quality of life in cancer survivors, to reduce radiation morbidities, and to maximize efficient health care use.

Survival outcomes of patients with localized FOXO1 fusion-positive rhabdomyosarcoma treated on recent clinical trials: A report from the Soft Tissue Sarcoma Committee of the Children's Oncology Group

BACKGROUND

The objective of this analysis was to evaluate the clinical factors influencing survival outcomes in patients with localized (clinical group I-III), FOXO1 fusion-positive rhabdomyosarcoma (RMS).

METHODS

Patients with confirmed FOXO1 fusion-positive RMS who were enrolled on 3 completed clinical trials for localized RMS were included in the analytic cohort. Outcomes were analyzed using the Kaplan-Meier method to estimate event-free survival (EFS) and overall survival (OS), and the curves were compared using the log-rank test. A Cox proportional hazards regression model was used to perform multivariate analysis of prognostic factors that were significant in the univariate analysis.

RESULTS

The estimated 4-year EFS and OS of 269 patients with localized, FOXO1 fusion-positive RMS was 53% (95% CI, 47%-59%) and 69% (95% CI, 63%-74%), respectively. Univariate analysis revealed that several known favorable clinical characteristics, including age at diagnosis between 1 and 9 years, complete surgical resection, tumor size ≤5 cm, favorable tumor site, absence of lymph node involvement, confinement to the anatomic site of origin, and PAX7-FOXO1 fusion, were associated with improved outcomes. Multivariate analysis identified older age (≥10 years) and large tumor size (>5 cm) as independent, adverse prognostic factors for EFS within this population, and patients who had both adverse features experienced substantially inferior outcomes.

CONCLUSIONS

Patients with localized, FOXO1 fusion-positive RMS can be further risk stratified based on clinical features at diagnosis, and older patients with large primary tumors have the poorest prognosis.

Role of Surgery in Rhabdomyosarcoma of the Head and Neck in Children

OBJECTIVES

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children. The goal of this research is to analyze the role of surgery in the management of pediatric parameningeal (PM) and non-PM head and neck RMS (HNRMS).

STUDY DESIGN

Retrospective review.

METHODS

Retrospective chart review of patients <20 years of age treated for HNRMS between 1970 and 2015. Clinical presentation, tumor characteristics, treatment, recurrence, follow-up, and outcome data were collected.

RESULTS

Of 97 patients with HNRMS, 56% were male. Overall median (IQR: interquartile range) age at diagnosis was 5.8 (3.3-9.8) years. Sixty-five patients (67%) had PM tumors. Of 75 patients with histologic subtype identified, 51 (53%) had embryonal and 20 (21%) alveolar RMS. Almost all patients received chemotherapy (99%) and radiotherapy (95%). Forty-four patients (45%) underwent surgery. Surgery was more likely to be conducted in patients with lesions of a non-PM site. Median follow-up time was 3.4 years (IQR: 1.1-10.8). In 5 years of follow-up, 20% (17 of 85) died and 29% (20 of 70) had recurrence. The estimated 5-year survival rate was 72% (95% CI, 57.8, 81.5%). Surgery was associated with a reduced risk of mortality after accounting for TNM stage 4 and tumor site (adjusted HR 0.24; 95% CI, 0.07, 0.79; P = .02). The association between surgery and risk of mortality was similar in PM and non-PM tumors.

CONCLUSION

A multimodal protocol for treatment including chemotherapy, surgery, and radiotherapy is the mainstay for management of children with HNRMS. While surgery is more commonly used to treat non-PM HNRMS, patients who are able to undergo surgery have significantly higher 5-year survival.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E984-E992, 2021.

Recent advances in understanding and managing pediatric rhabdomyosarcoma

Rhabdomyosarcoma (RMS) is a high-grade malignant neoplasm, with a morphologic appearance mimicking that of developing skeletal muscle. Over the last 30 years, patient outcomes have improved with the incorporation of multimodal therapies, including chemotherapy, radiation therapy, and surgery. The overall cure rates exceed 70%, with patients who have low-, intermediate-, and high-risk disease experiencing long-term survival rates of >90%, 70%, and <30%, respectively. Historically, RMS was classified according to histology; however, recent advances have revealed new molecular subgroups that allow us to more accurately identify high-, intermediate-, and low-risk disease. In this review, we discuss recent advances made in understanding RMS tumor biology and propose how this understanding can drive a new classification system that can guide clinical approaches for treatment de-escalation in patients with expected favorable outcomes and escalation for those with expected poor outcomes.

Efficacy and Safety of Limited-Margin Conformal Radiation Therapy for Pediatric Rhabdomyosarcoma: Long-Term Results of a Phase 2 Study

PURPOSE

Our purpose was to assess disease outcomes and late toxicities in pediatric patients with rhabdomyosarcoma treated with conformal photon radiation therapy (RT).

METHODS AND MATERIALS

Sixty-eight patients (median age, 6.9 years) were treated with conformal photon RT to the primary site on a prospective clinical trial. Target volumes included a 1-cm expansion encompassing microscopic disease. Prescribed doses were 36 Gy to this target volume and 50.4 Gy to gross residual disease. Chemotherapy consisted of vincristine/dactinomycin (n = 6), vincristine/dactinomycin/cyclophosphamide (n = 37), or vincristine/dactinomycin/cyclophosphamide-based combinations (n = 25). Patients were evaluated with primary-site magnetic resonance imaging, whole-body [¹⁸F]fluorodeoxyglucose positron emission tomography, and chest computed tomography for 5 years after treatment.

RESULTS

Five-year disease-free survival was 88% for low-risk (n = 8), 76% for intermediate-risk (n = 37), and 36% for high-risk (n = 23) patients (P ≤ .01 for low risk/intermediate risk vs high risk). The cumulative incidence of local failure (LF) at 5 years for the entire cohort was 10.4%. Tumor size at diagnosis was a significant predictor of LF (P < .01). Patients with head and neck primary tumors (n = 31) had a 35% cumulative incidence of cataracts; the risk correlated with lens dose (P = .0025). Jaw dysfunction was more severe when the pterygoid and masseter muscles received a mean dose of >20 Gy (P = .013). Orbital hypoplasia developed more frequently after a mean bony orbit dose of >30 Gy (P = .041). Late toxicity in patients with genitourinary tumors included microscopic hematuria (9 of 14), bladder-wall thickening (10 of 14), and vaginal stenosis (2 of 5).

CONCLUSIONS

Long-term LF rates were low, and higher rates correlated with larger tumors. Treatment-related toxicities resulting in measurable functional deficits were not infrequent, despite the conformal RT approach.

Increased local failure for patients with intermediate-risk rhabdomyosarcoma on ARST0531: A report from the Children's Oncology Group

BACKGROUND

The objective of this study was to evaluate local control for patients with intermediate-risk rhabdomyosarcoma (RMS) treated on Children's Oncology Group (COG) protocol ARST0531.

METHODS

This study analyzed 424 patients with intermediate-risk RMS. Patients were randomized to chemotherapy with either vincristine, dactinomycin, and cyclophosphamide (VAC) or VAC alternating with vincristine and irinotecan. With the goal of improving local control, radiation therapy (RT) was delivered early at week 4 and was concurrent with irinotecan in the experimental arm. Individualized local control plans for children 24 months old or younger were allowed. Local failure on ARST0531 was compared with local failure on the preceding COG intermediate-risk study, D9803.

RESULTS

For patients with group I/II alveolar RMS (n = 55), the 5-year cumulative incidence of local failure was 13.4%; for group III alveolar RMS (n = 141), it was 20.2%; and for group III embryonal RMS (n = 228), it was 27.9% (P = .03). Among patients with group III disease, local failure did not differ by histology, site, nodal status, RT modality, or treatment arm. Local failure was worse for a tumor size >5 cm (32.3% vs 16.7%; P = .001). Among patients with group III embryonal RMS, local failure was higher on ARST0531 than D9803 (27.9% vs 19.4%; P = .03). After the exclusion of patients 24 months old or younger or patients who did not receive radiation, local failure remained significantly increased on ARST0531 (P = .02). After adjustments for clinical prognostic factors, event-free survival and overall survival were worse on ARST0531 (P = .004 and P = .05, respectively).

CONCLUSIONS

Despite interventions designed to enhance local control, local control was inferior on ARST0531 in comparison with D9803. The reason for this is unclear, but it could be the reduced cyclophosphamide dose on ARST0531.