Rhabdomyosarcoma in infants younger than 1 year: a report from the Children's Oncology Group

Exceptional case of a hemangioma-like rabdomyosarcoma in the hand's palm

Rhabdomyosarcoma is a malignant tumor in children that might mimic a benign tumor, such as infantile hemangioma, particularly when detected early. Although rhabdomyosarcoma rarely occurs in the hand, its prognosis is generally poor, and successful treatment relies on a complete and radical surgical excision. We present a case of rhabdomyosarcoma located in the palm of an infant's hand, initially presenting clinical and radiological features suggestive of a vascular tumor. The resection of this mass was radical, and histological analysis and immunohistochemistry returned in favor of embryonic rhabdomyosarcoma. In similar cases recorded in the literature, the diagnosis may be first mistaken for that of a hemangioma, then confirmed by histology. This underlines the importance of a systematic anatomopathological examination of all tissues removed surgically.

Contemporary preclinical mouse models for pediatric rhabdomyosarcoma: from bedside to bench to bedside

Background

Rhabdomyosarcoma (RMS) is the most common pediatric soft-tissue malignancy, characterized by high clinicalopathological and molecular heterogeneity. Preclinical in vivo models are essential for advancing our understanding of RMS oncobiology and developing novel treatment strategies. However, the diversity of scholarly data on preclinical RMS studies may challenge scientists and clinicians. Hence, we performed a systematic literature survey of contemporary RMS mouse models to characterize their phenotypes and assess their translational relevance.

Methods

We identified papers published between 01/07/2018 and 01/07/2023 by searching PubMed and Web of Science databases.

Results

Out of 713 records screened, 118 studies (26.9%) were included in the qualitative synthesis. Cell line-derived xenografts (CDX) were the most commonly utilized (n = 75, 63.6%), followed by patient-derived xenografts (PDX) and syngeneic models, each accounting for 11.9% (n = 14), and genetically engineered mouse models (GEMM) (n = 7, 5.9%). Combinations of different model categories were reported in 5.9% (n = 7) of studies. One study employed a virus-induced RMS model. Overall, 40.0% (n = 30) of the studies utilizing CDX models established alveolar RMS (aRMS), while 38.7% (n = 29) were embryonal phenotypes (eRMS). There were 20.0% (n = 15) of studies that involved a combination of both aRMS and eRMS subtypes. In one study (1.3%), the RMS phenotype was spindle cell/sclerosing. Subcutaneous xenografts (n = 66, 55.9%) were more frequently used compared to orthotopic models (n = 29, 24.6%). Notably, none of the employed cell lines were derived from primary untreated tumors. Only a minority of studies investigated disseminated RMS phenotypes (n = 16, 13.6%). The utilization areas of RMS models included testing drugs (n = 64, 54.2%), studying tumorigenesis (n = 56, 47.5%), tumor modeling (n = 19, 16.1%), imaging (n = 9, 7.6%), radiotherapy (n = 6, 5.1%), long-term effects related to radiotherapy (n = 3, 2.5%), and investigating biomarkers (n = 1, 0.8%). Notably, no preclinical studies focused on surgery.

Conclusions

This up-to-date review highlights the need for mouse models with dissemination phenotypes and cell lines from primary untreated tumors. Furthermore, efforts should be directed towards underexplored areas such as surgery, radiotherapy, and biomarkers.

Solid and Vascular Neck Masses in Children

Neck masses are frequent in the pediatric population and are usually divided into congenital, inflammatory, and neoplastic. Many of these lesions are cystic and are often benign. Solid masses and vascular lesions are relatively less common, and the imaging appearances can be similar. This article reviews the clinical presentation and imaging patterns of pediatric solid and vascular neck masses.

Congenital Neck Masses

There are many possible causes of congenital neck masses, with the most common ones being thyroglossal duct cysts, branchial cleft anomalies, and vascular malformations. Most congenital neck masses are asymptomatic in the neonatal period, but depending on the location and the size, they can cause airway obstruction and serious complications at birth. Proper diagnosis is important for optimal treatment planning, and if the airway is compromised, multidisciplinary teamwork is critical for proper airway management. This review summarizes the clinical features, etiology, diagnosis, management, and prognosis of different types of congenital neck masses.

Clinical features and outcomes of infantile soft-tissue sarcoma: A multicenter retrospective study in Beijing

Background

Soft-tissue sarcomas during infancy are rare and understudied. With no data on this specific condition, we performed a retrospective study of infant-onset sarcomas based on a multi-institutional cohort in Beijing, China, collected over the past decade. We reviewed infantile soft-tissue sarcomas' clinical characteristics, treatments, and outcomes.

Materials and Methods

The patients with soft-tissue sarcoma diagnosed from 0 to 12 months in four primary children's hospitals in Beijing from January 2010 to December 2019 were evaluated.

Results

Fifty-one patients were enrolled, including 31 males and 20 females. The median age at the diagnosis was five months (range, 0-12), and seven (13.7%) patients were diagnosed in the first month of their life. Histologically, twenty-five patients were diagnosed with rhabdomyosarcoma (RMS), six were diagnosed with extraosseous Ewing sarcoma (EES), and twenty were diagnosed with nonrhabdomyosarcoma soft-tissue sarcoma (NRSTS). The treatment principles and details of RMS focused on reference to the Intergroup Rhabdomyosarcoma Study Group (IRSG) protocols. For EES and NRSTS, chemotherapy was prescribed according to children's oncology group protocols. The five-year EFS/OS rates of RMS were 26.4% ± 19.5%/56.2 ± 17.8%, the five-year EFS/OS rate of EES was 50% ± 20.4%, and the five-year EFS/OS of NRSTS was 85.2% ± 9.8%/100%.

Conclusions

Infant-onset soft-tissue sarcoma is heterogeneous. The primary location of the abdominal or pelvic cavity of RMS and EWS was at a later stage and had a poorer prognosis. Multimodal therapy resulted in successful disease control for the majority of patients. Standardization of treatment protocols will facilitate care for such challenging conditions.

Clinical Characteristics, Treatment Considerations, and Outcomes of Infants with Rhabdomyosarcoma

RMS most commonly presents in children and adolescents, however a subset of tumors are diagnosed in infants under one year of age. Due to the rarity of infant RMS, utilization of different treatment approaches and goals, and small sample sizes, the published studies of infants with RMS have yielded heterogeneous results. In this review, we discuss the outcomes of infants with RMS treated in various clinical trials and the strategies that various international cooperative groups have employed to reduce the morbidity and mortality related to treatment without compromising the overall survival of this population. This review discusses the unique scenarios of diagnosing and managing congenitals or neonatal RMS, spindle cell RMS and relapsed RMS. This review concludes by exploring novel approaches to diagnosis and management of infants with RMS that are currently being studied by various international cooperative groups.

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.

Developments in the Surgical Approach to Staging and Resection of Rhabdomyosarcoma

Although survival after rhabdosarcoma treatment has improved over the years, one third of patients still develop locoregional relapse. This review aims to highlight developments pertaining to staging and local treatment of specific RMS tumor sites, including head and neck, chest/trunk, bladder-prostate, female genito-urinary, perianal, and extremity sites.

Case report: Clinical features and prognosis of two Infants with rhabdomyosarcoma of the tongue

Background

Rhabdomyosarcoma (RMS) is the most common soft tissue tumor in children, and its most common pathological types include embryonal RMS and alveolar RMS. In contrast, spindle cell RMS (SRMS) is a rare type. Moreover, the tongue is a rare primary site of RMS, and infancy is a rare age at onset.

Case presentation

Two infants were diagnosed with lingual RMS at 3 and 5 months after birth, respectively, and were admitted to Beijing Children's Hospital. The pathological type in both cases was SRMS. Both were classified as low-risk and were treated with surgery and chemotherapy. Case 1 was in complete remission at the latest follow-up, and Case 2 had a relapse 10 months after stopping chemotherapy, achieving complete remission after the multimodal treatment of chemotherapy, surgery, and radiotherapy. The venous blood gene test of the two infants did not indicate a pathogenic mutation or a possible pathogenic mutation related to RMS. In Case 1, variants of the CDK4 and BRCA1 genes, both with unknown significance and a possible relation to RMS, were detected. In Case 2, three gene variants of unknown significance that were possibly associated with RMS-TRIP13, APC, and RAD54L-were identified.

Conclusion

Lingual RMS in infants is rare. Its clinical manifestations lack specificity, and early recognition is complex. The success and timing of local treatment are important prognostic factors. Genetic testing may be helpful for the early detection of tumor susceptibility and the estimation of prognosis.

Infant prostatic Rhabdomyosarcoma: A diagnostic and therapeutic challenge

The following case report describes a case of prostatic rhabdomyosarcoma in a 6-month-old male who presented with urinary retention and constipation. MRI showed a prostatic mass that was displacing the rectum and bladder, leading to bladder outlet obstruction. A suprapubic tube was placed for urinary diversion and a transvesical approach was used for tissue diagnosis. Biopsy confirmed the diagnosis of prostatic rhabdomyosarcoma. Patient underwent chemotherapy regiment with VAC (vincristine, actinomycin D and cyclophosphamide) and subsequently ifosfamide and doxorubicin. Eventually, due to tumor progression, the patient underwent a radical cystoprostatectomy with pelvic lymph node dissection and ileal conduit.

Importance of histopathological analysis and molecular genetics in a rare neonatal case of rhabdomyosarcoma

We present a case of a neonate who presented with multiple cutaneous and subcutaneous nodules, which was found to be metastatic embryonal rhabdomyosarcoma. Rhabdomyosarcoma is a soft tissue malignancy that usually occurs in children aged one to five but is rare in neonates. The histopathological analysis and molecular genetics are important in the classification of subtype and in guiding treatment options and informing prognosis.

Congenital spindle cell rhabdomyosarcoma: An international cooperative analysis

BACKGROUND

Spindle cell rhabdomyosarcoma (RMS) is a rare variant of RMS accounting for up to 10% of cases in infants. In older children and adults, spindle cell RMS is associated with MYOD1 mutations and a poor prognosis. In infants, it is associated with recurring fusions involving NCOA2 and VGLL2. Reports in the literature suggest a favorable prognosis for this subset, however, little is known about treatment and outcome data of infants with spindle cell RMS.

METHODS

Characteristics, treatment, and outcome of an international cohort of 40 patients aged ≤ 12 months with spindle cell RMS treated from 1997 to 2018 were evaluated.

RESULTS

Localized disease (LD) was diagnosed in 39 patients. The median age at diagnosis was 2.5 months (range 0-12 months). Expert pathologic review confirmed the diagnosis of spindle cell RMS in all patients. Among 26 tumors that had molecular evaluation, 13 had rearrangements of NCOA and/or VGLL. Multimodal treatment of infants with LD included conventional (age adjusted) chemotherapy (n = 37), resection (n = 31) and radiotherapy (RT) (n = 5, brachytherapy in 3). Complete remission was achieved in 37/39 patients. Progressive disease occurred in two infants, relapsed disease in three. Microscopically complete surgical resection was associated with five-year event-free survival (EFS) and overall survival (OS) of 100%. Two patients with tumors ≤ 5 cm were treated with microscopically complete resection only and were alive 1 and 4.2 years after diagnosis. The 5-year EFS and OS for infants with LD were 86% (±11; CI 95%) and 91% (±9; CI 95%), respectively. One patient had metastatic disease (NCOA fusion positive) with primary tumor in head and neck and brain metastases. This patient died despite chemotherapy and delayed resection of the primary tumor due to respiratory failure secondary to cytomegalovirus infection 1.2 years after diagnosis.

CONCLUSION

Infants with spindle cell RMS have an excellent prognosis. Multimodal treatment including microscopically complete resection of the tumor is strongly recommended.

Congenital rhabdomyosarcoma: A report from the European paediatric Soft tissue sarcoma Study Group

PROCEDURE

Congenital rhabdomyosarcoma (RMS) represents a challenging disease due to its characteristics and the difficulties in delivering treatment in this immature population.

METHODS

We analyzed treatment and outcome of patients with congenital RMS, defined as tumor diagnosed in the first 2 months of life, enrolled in the European paediatric Soft tissue sarcoma Study Group protocols.

RESULTS

Twenty-four patients with congenital RMS were registered. All, except one patient (PAX3-FOXO1-positive metastatic RMS), had favorable histology and localized disease. Three patients had VGLL2-CITED2/NCOA2 fusion. Complete tumor resection was achieved in 10 patients. No radiotherapy was given. Chemotherapy doses were adjusted to age and weight. Only two patients required further dose reduction for toxicity. The 5-year event-free survival (EFS) and overall survival (OS) were 75.0% (95% confidence interval [CI] 52.6-87.9) and 87.3% (95% CI 65.6-95.7), respectively. Progressive disease was the main cause of treatment failure.

CONCLUSION

Patients with congenital RMS presented with a favorable disease, allowing weight- and age-adjusted doses of chemotherapy and avoidance of irradiation, without compromising the outcome.

Localised rhabdomyosarcoma in infants (<12 months) and young children (12-36 months of age) treated on the EpSSG RMS 2005 study

BACKGROUND

Infants (<12 months) with rhabdomyosarcoma have historically had poorer outcome than the older age groups. We present outcomes for infants and young children aged 12-36 months with localised rhabdomyosarcoma with a particular emphasis on infants.

PATIENTS AND METHODS

All children less than 36 months of age enrolled on the EpSSG RMS 2005 study for localised disease are included. Treatment comprised chemotherapy, local surgery and/or radiation therapy adapted to risk group and age. Main outcome measures were event free survival (EFS) and overall survival (OS).

RESULTS

Outcome data were available for 485/490 patients aged less than 36 months, 110 were infants. Infants received chemotherapy according to the risk group with no toxic deaths. Radiotherapy was delivered to 33.6% of infants and 63.5% of 12-36 months old, with respectively 41.7% and 22.2% receiving brachytherapy. Radical surgery was performed in 62% of infants and 57.1% of 12-36 months old. Median follow up for patients who are alive (n = 393) was 72.7 months (range 6.9-158.2). Five-year OS for infants was 88.4% (95%CI 80.3-93.2), which is significantly better than the OS in 12-36 months old patients of 78.0% (95%CI 73.2-82.0; p = 0.0204). Five-year EFS for infants was 72.5% (95%CI 62.8-80.0) compared with 66.1% (95%CI 61.0-70.7; p = 0.2663) for 12-36 months old.

CONCLUSION

Infants treated on RMS 2005 achieved excellent EFS and OS. The EpSSG RMS 2005 chemotherapy regimen, combined with an increase in the application of adequate local therapy, improvements in imaging and supportive care and potentially favourable patients' characteristics may have contributed to these results.

Genomic Classification and Clinical Outcome in Rhabdomyosarcoma: A Report From an International Consortium

PURPOSE

Rhabdomyosarcoma is the most common soft tissue sarcoma of childhood. Despite aggressive therapy, the 5-year survival rate for patients with metastatic or recurrent disease remains poor, and beyond PAX-FOXO1 fusion status, no genomic markers are available for risk stratification. We present an international consortium study designed to determine the incidence of driver mutations and their association with clinical outcome.

PATIENTS AND METHODS

Tumor samples collected from patients enrolled on Children's Oncology Group trials (1998-2017) and UK patients enrolled on malignant mesenchymal tumor and RMS2005 (1995-2016) trials were subjected to custom-capture sequencing. Mutations, indels, gene deletions, and amplifications were identified, and survival analysis was performed.

RESULTS

DNA from 641 patients was suitable for analyses. A median of one mutation was found per tumor. In FOXO1 fusion-negative cases, mutation of any RAS pathway member was found in > 50% of cases, and 21% had no putative driver mutation identified. BCOR (15%), NF1 (15%), and TP53 (13%) mutations were found at a higher incidence than previously reported and TP53 mutations were associated with worse outcomes in both fusion-negative and FOXO1 fusion-positive cases. Interestingly, mutations in RAS isoforms predominated in infants < 1 year (64% of cases). Mutation of MYOD1 was associated with histologic patterns beyond those previously described, older age, head and neck primary site, and a dismal survival. Finally, we provide a searchable companion database (ClinOmics), containing all genomic variants, and clinical annotation including survival data.

CONCLUSION

This is the largest genomic characterization of clinically annotated rhabdomyosarcoma tumors to date and provides prognostic genetic features that refine risk stratification and will be incorporated into prospective trials.

Prenatal Diagnosis of a Facial Teratoma. A Proposed Approach to Diagnose Prenatal Facial Anomalies

We report on a rare case of a prenatally diagnosed isolated facial teratoma, presenting as an avascular elongated ossified lesion arising from the inferior lateral rim of the orbit. There was no evidence of fetal compromise throughout the course of the pregnancy, which resulted in term delivery of a healthy neonate by elective Caesarean section. We summarize the key features, differential diagnoses, prognosis and management of fetal facial lesions.

Germline ATM mutation and somatic PIK3CA and BCOR mutations found in an infant with aggressive orbital embryonal rhabdomyosarcoma

Purpose

To report a case of aggressive infantile orbital embryonal rhabdomyosarcoma harboring germline ATM mutation and 2 somatic mutations as revealed by next-generation sequencing and the potential application for personalized therapy.

Observations

A 7-month-old male developed a rapidly progressive left proptosis over 6 weeks due to a large medial orbital mass. Biopsy revealed embryonal rhabdomyosarcoma. After the first cycle of chemotherapy, re-imaging showed interval tumor enlargement with intracranial extension. Craniotomy, combined with orbital exenteration, was performed. Tumor specimens and blood samples were sent for 596 gene DNA sequencing panels with RNA-sequencing focused on actionable mutations as well as gene fusion detection. Sequencing revealed 3 clinically relevant mutations: a germline ATM loss-of-function (LOF) mutation, a somatic PIK3CA gain-of-function mutation, and a somatic BCOR LOF mutation. No chromosomal translocation was detected. Workup for metastasis was positive for bone marrow involvement. Despite standard high-dose adjuvant chemotherapy in combination with radiation therapy, the patient died 10 months later with metastatic diseases.

Conclusions and importance

This case highlights an aggressive form of embryonal rhabdomyosarcoma in an infantile orbit. The presence of germline mutation may explain the increased chemo-resistance and adverse prognosis, and may be used as the target for genomic-directed therapy.

Non-rhabdomyosarcoma soft tissue sarcomas diagnosed in patients at a young age. An overview of clinical, pathological, and molecular findings

OBJECTIVE

Disease spectrum in pediatric sarcoma differs substantially from adults. We report a cohort of very young children with non-rhabdomyosarcoma soft tissue sarcoma (NRSTS) detailing their molecular features, treatment, and outcome.

METHODS

We report features of consecutive children (age <2 years) with NRSTS (2000-2017). Archival pathological material was re-reviewed, with additional molecular techniques applied where indicated.

RESULTS

Twenty-nine patients (16 females, 55%) were identified (median age 6 months; range 0-23). Most common diagnoses included infantile fibrosarcoma (IFS, n = 14, 48%), malignant rhabdoid tumor (MRT, n = 4, 14%), and undifferentiated sarcoma (n = 4, 14%). Twenty-seven of 29 (93%) had tumor molecular characterization to confirm diagnosis. Clinical presentation included a swelling/mass (n = 23, 79%). Disease extent was localized (n = 20, 69%), locoregional (n = 6, 21%), or metastatic (n = 3, 10%). Seventeen of 29 (59%) who underwent surgery achieved complete resection (R0). Other treatments included conventional chemotherapy (n = 26, 90%), molecularly targeted therapies (n = 3, 10%), and radiation (n = 5, 17%). At last follow-up (median 3 years; range 0.3-16.4), 23 (79%) were alive, disease-free and six (21%) had died of disease. All patients with IFS were alive and all those with MRT died. A cancer predisposition syndrome (CPS) was confirmed in three of 10 (30%) genetically tested patients.

CONCLUSION

We recommend tumor molecular characterization in all young patients including evaluation for CPS to optimize treatment options and prognostication.

Clinical characteristics and outcomes of infants compared with children diagnosed with rhabdomyosarcoma: Analysis of surveillance, epidemiology and end results data from 2000 to 2016

BACKGROUND

Rhabdomyosarcoma (RMS) is the most common soft-tissue sarcoma of childhood, but occurs infrequently in infants (<1 year). Historically, infants with RMS have worse overall survival compared to other pediatric age groups.

AIM

This study aims to assess the clinical features and treatment factors associated with survival comparing infants to children aged 1-9 years diagnosed with RMS.

METHODS

Children aged <10 years diagnosed with RMS between 2000 and 2016 were identified using the SEER database. Descriptive statistics were used to assess demographic, clinical, and treatment characteristics of infants and children with RMS. Kaplan-Meier estimates and Cox proportional hazards regression were performed to assess for factors associated with survival.

RESULTS

Age <1 year was independently associated with an increased risk of mortality. Compared to children aged 1-9 years, fewer infants received standard of care therapy, that is, chemotherapy combined with local control (surgery and/or radiation; 86.8 vs. 75.7%; p = .009). In comparing the frequency of specific treatment modalities (used alone or in combination with other modalities), infants were less likely to receive radiation therapy (34.0 vs. 66.4%; p < .001) and more likely to receive surgery (68.9 vs. 57.5%; p = .02) than children aged 1-9 years. Across age groups, chemotherapy combined with local control was significantly associated with reduced mortality. Alveolar histology, metastatic disease, and Hispanic ethnicity were negatively associated with survival.

CONCLUSIONS

Age of <1 year was an independent risk factor for increased mortality from RMS compared to ages 1-9 years. Fewer infants were treated with chemotherapy combined with local control, the therapy associated with best survival in all age groups. Other factors contributing to differences in survival should be further explored.

Proton radiotherapy for infant rhabdomyosarcoma: Rethinking young age as an adverse prognostic factor

BACKGROUND & PURPOSE

In infants with rhabdomyosarcoma, young age is considered an adverse prognostic factor and treatment is often attenuated to reduce side effects. Proton therapy may improve the therapeutic ratio in these patients. We report outcomes in infants with rhabdomyosarcoma treated with proton therapy.

MATERIALS & METHODS

Between 2009 and 2019, 37 infants <24 months old with non-metastatic rhabdomyosarcoma received proton therapy. Local control (LC), progression-free survival (PFS), and overall survival (OS) were estimated using the Kaplan-Meier product limit. The log-rank test assessed significance between selected prognostic factors. Toxicity was graded per CTCAEv5.0.

RESULTS

Median follow-up was 5.1 years. Overall, 76% of patients had an unfavorable primary site. Median dose was 50.4GyRBE. At 5 years, LC, PFS, and OS rates were 83%, 78%, and 83%. On univariate analysis, 5-year LC and OS were inferior for favorable versus unfavorable disease sites (67% vs 89%, 67% vs 89%, respectively; p < .05) and 5-year OS was superior in stage 3 versus stage 1-2 disease (91% vs 69%; p = .05), owing to inclusion of nasal ala patients among stage 1. Of 9 recurrences, 7 were in-field, 4 occurring in infants with nasal ala primaries. Recategorizing nasal ala as an unfavorable site resulted in 100% 5-year LC and OS for favorable sites. Six infants experienced late grade 3 toxicity. None developed grade 4 or 5 late toxicity.

CONCLUSIONS

Young age alone may not be an adverse prognostic factor provided infants receive local therapy similar to older children. Consideration should be given to classifying nasal ala primaries as an unfavorable site.

Radiation therapy for infants with cancer

The clinical outcomes for infants with malignant tumors are often worse than older children due to a combination of more biologically aggressive disease in some cases, and increased toxicity-or deintensification of therapies due to concern for toxicity-in others. Especially in infants and very young children, finding the appropriate balance between maximizing treatment efficacy while minimizing toxicity-in particular late side effects-is crucial. We review here the management of malignant tumors in infants and very young children, focusing on central nervous system (CNS) malignancies and rhabdomyosarcoma.

Nasal Embryonal Rhabdomyosarcoma in the Pediatric Population: Literature Review and Report of Midline Presentation

Background:

Congenital midline nasal masses are rare anomalies and are typically benign nasal dermoid sinus cysts (NDSCs). Rhabdomyosarcomas (RMSs) are even less common, and only a fraction affect sites like the external nose, nasal cavity, nasopharynx, and paranasal sinuses. We review the clinical presentation and treatment of nasal, nasopharyngeal, and paranasal RMSs and report the first documented midline presentation.

Methods:

We queried PubMed for articles with titles containing the terms rhabdomyosarcoma or sarcoma botryoides and nose, nasal, paranasal, sinonasal, nasopharynx, or nasopharyngeal. We then searched the references of each included article using the same parameters and continued this process iteratively until no new articles were found.

Results:

The paranasal sinuses were the most commonly affected site, followed by the nasopharynx, nasal cavity, and external nose. Two patients presented with involvement of the external nose, but each presented with involvement of the right ala rather than a midline mass. The rates of intracranial extension and/or skull base involvement were comparable to those of NDSCs. The alveolar subtype was most common, followed by the embryonal subtype.

Conclusions:

Most midline nasal masses are benign; however, we report the first documented presentation of an RMS as a midline nasal mass. Accordingly, RMS should be included in the differential diagnosis of midline nasal masses in the pediatric population. Surgery for midline nasal masses is sometimes delayed due to the risks of interfering with developing structures and early anesthesia. However, early surgical treatment should be considered given this new differential and its predilection for early metastasis.

Rhabdomyosarcoma of the female genitourinary tract: Primary and relapsed disease in infants and older children. Treatment results of five Cooperative Weichteilsarkom Studiengruppe (CWS) trials and one registry

BACKGROUND

Rhabdomyosarcoma (RMS) of the female genitourinary tract (FGU-RMS) located at the vagina or uterus is one of the most favorable RMS sites. Little is known about treatment and outcome in infants and relapsed disease (RD).

METHODS

Characteristics, treatment, and outcome of 71 children with FGU-RMS registered within five Cooperative Weichteilsarkom Studiengruppe (CWS) trials and one registry (1981-2019) were evaluated.

RESULTS

FGU-RMS was diagnosed in 67 patients with localized disease (LD) at a median age of 2.89 years (0.09-18.08). Multimodal treatment consisted of chemotherapy (CHT) (n = 66), secondary surgery (n = 32), and radiotherapy (n = 11). Age at diagnosis ≤12 months was the only significant negative prognostic factor influencing the event-free survival (EFS). Ten-year EFS and overall survival (OS) for infants ≤12 months were 50% and 81%, respectively. In contrast, children with LD >1 year and ≤10 years had a 10-year EFS and OS of 78% and 94% (P = .038), and >10 years of 82% and 88%, respectively (P = .53). Metastatic disease was observed in four patients of which three are alive. RD occurred in five of 12 infants ≤1 year and 10/55 children at a median of 1.38 years (0.53-2.97) after initial diagnosis. Treatment of patients with RD consisted of multimodal treatment (n = 13) or resection only (n = 2). Nine patients (60%) were alive in clinical remission at a median of 7.02 years (1.23-16.72) after diagnosis of RD.

CONCLUSION

Infants with FGU-RMS have a higher relapse rate than older children with FGU-RMS, but prognosis is fair.

Advances in the Diagnosis and Management of Neonatal Sarcomas

Neonatal sarcomas comprise a heterogeneous group of rare soft tissue neoplasms that present unique diagnostic and therapeutic challenges. Recent advances in molecular profiling have improved diagnostic capabilities and reveal novel therapeutic targets. Clinical trials demonstrate differences in behavior between sarcoma subtypes that allow for better clinical management. Surgical resection has been replaced with a multimodal approach that includes chemotherapy and radiotherapy. Despite these advances, neonates with sarcoma continue to fare worse than histologically similar sarcomas in older children, likely reflecting differences in tumor biology and the complexities of neonatal medicine. This review focuses on recent advances in managing neonatal sarcomas.

Relapsed Rhabdomyosarcoma

Relapsed rhabdomyosarcoma (RMS) represents a significant therapeutic challenge. Nearly one-third of patients diagnosed with localized RMS and over two-thirds of patients with metastatic RMS will experience disease recurrence following primary treatment, generally within three years. Clinical features at diagnosis, including primary site, tumor invasiveness, size, stage, and histology impact likelihood of relapse and prognosis post-relapse. Aspects of initial treatment, including extent of surgical resection, use of radiotherapy, and chemotherapy regimen, are also associated with post-relapse outcomes, as are features of the relapse itself, including time to relapse and extent of disease involvement. Although there is no standard treatment for patients with relapsed RMS, several general principles, including tissue biopsy confirmation of diagnosis, assessment of post-relapse prognosis, determination of the feasibility of additional local control measures, and discussion of patient goals, should all be part of the approach to care. Patients with features suggestive of a favorable prognosis, which include those with botryoid RMS or stage 1 or group I embryonal RMS (ERMS) who have had no prior treatment with cyclophosphamide, have the highest chance of achieving long-term cure when treated with a multiagent chemotherapy regimen at relapse. Unfortunately, patients who do not meet these criteria represent the majority and have poor outcomes when treated with such regimens. For this group, strong consideration should be given for enrollment on a clinical trial.

Advances in the management of pediatric genitourinary rhabdomyosarcoma

Recent clinical trials have revealed several unanticipated complexities in the optimal management of genitourinary rhabdomyosarcoma (RMS). Improvement in outcomes for low- and intermediate-risk RMS over the past several decades led to the design of clinical trials aimed at reducing acute and late toxicity from extirpative surgeries, conventional radiotherapy, and cytotoxic chemotherapy. Results from these studies are mixed and have illuminated areas where historical risk stratification strategies need refining. Although radiotherapy has now become the standard for local control for most patients with genitourinary RMS, recent studies are demonstrating that there may be opportunities to minimize radiation toxicity while maintaining acceptable failure-free survival. A reduction in cyclophosphamide exposure may benefit select low-risk RMS patients but recent results illustrate that decreasing therapy intensity for most genitourinary RMS patients will require careful consideration in future prospective trials. Finally, recent studies highlight differences in perspective between European and North American investigators regarding the optimal balance of increased local failure rates but less toxicity versus improved event-free survival at a cost of higher toxicity. This review focuses on the results from the most recent RMS clinical trials and discusses their implications for the management of pediatric genitourinary RMS.

Update on pediatric rhabdomyosarcoma: A report from the APSA Cancer Committee

BACKGROUND/PURPOSE

Rhabdomyosarcoma is the most common soft tissue sarcoma in children and young adults and requires multimodality treatment. The purpose of this review is to present an update on risk stratification as well as surgical and medical management strategies in pediatric rhabdomyosarcoma.

METHODS

A comprehensive review of the current literature on pediatric rhabdomyosarcoma, including the most recent Children's Oncology Group studies and several international collaboratives, was performed by the authors and key findings were summarized in the manuscript.

RESULTS

FOXO1 fusion status is a stronger prognostic factor than histology and is now used for risk stratification in treatment protocols. For assessment of regional nodal involvement, FDG-PET-CT shows poor sensitivity and specificity to detect histologically confirmed nodal metastasis. Thus, surgical assessment of regional lymph nodes is required for rhabdomyosarcoma of the extremities or trunk as well as paratesticular rhabdomyosarcoma in patients ≥10 years of age, although adherence to surgical guidelines remains poor. Hemiscrotectomy performed for scrotal violation in paratesticular rhabdomyosarcoma has not shown an improvement in event free survival and is not recommended.

CONCLUSIONS

Surgical and medical treatment strategies for rhabdomyosarcoma in children continue to evolve. This review provides current evidence-based treatment standards with an emphasis on surgical care.

TYPE OF STUDY

Review.

LEVEL OF EVIDENCE

Level IV.

Chemopreventive Effects and Antioxidant Capacity of Combined Leaf Extracts of Sesamum angustifolium (Oliv.) Engl. and Hibiscus articulatus on Rhabdomyosarcoma

Sesamum angustifolium (Oliv.) Engl. and Hibiscus articulatus contain compounds that have antimutagenic properties. The rise in rhabdomyosarcoma in paediatrics and prognosis of the disease in infants compared to adults calls for newer, less toxic alternatives in treatment of the disease. The aim of this study was to determine the anticancer activity and antioxidant capacity of combined leaf extracts of Sesamum angustifolium (Oliv.) Engl. and Hibiscus articulatus (SAHA), against rhabdomyosarcoma (RMS) using rhabdomyosarcoma (RD) cell line and mouse (L20B) cell line. Cytotoxicity, morphology, apoptosis induction, and antioxidant capacity assays were done. Of the four solvents used for extraction, the dichloromethane SAHA extract was the most cytotoxic with IC₅₀ of 106 μg/mL after doxorubicin, the reference anticancer drug with IC₅₀ of 0.8 μg/mL. The SAHA extracts had a stronger cytotoxicity effect on the cancerous RD cells than on normal L20B cells. Morphological assessment showed untreated cells maintained their normal striated appearance of muscle cells whereas cells treated with doxorubicin or SAHA extracts exhibited cell shrinkage, loss of surface adherence, reduced cell density along with cell debris, which is a characteristic of apoptosis. Normal L20B cells when treated with doxorubicin or SAHA extracts, maintained their cell shape, and remained adherent to the surface. The apoptotic enzyme caspase-3 was induced in a concentration dependent manner upon treatment of the RD cells with SAHA extracts or doxorubicin. Induction of caspase-3 was ten times less in treated L20B cells compared to the RD cells. Low induction of caspase-9 enzyme was observed in both treated RD and L20B cells. Treatment of both RD and L20B cells with SAHA extracts or doxorubicin resulted in increased activity of peroxidase and reduction of oxidative stress. Results of the study show that the SAHA extracts are potential sources of compounds that may serve as useful agents for treatment of rhabdomyosarcoma.

Integrative clinical and biopathology analyses to understand the clinical heterogeneity of infantile rhabdomyosarcoma: A report from the French MMT committee

BACKGROUND

Rhabdomyosarcoma (RMS) in infants is a particular entity with various clinical presentations and outcomes. To better understand the clinical heterogeneity of RMS in infants, an integrative clinical, histological, and molecular analysis was performed.

METHODS

From 1989 to 2015, 37 infants aged less than 6 months with a diagnosis of RMS and archival tumor materials were identified in France. Clinical data, central pathologic review, and molecular profile including RNA sequencing were analyzed.

RESULTS

Nineteen patients (51%) had embryonal RMS (ERMS) (including three highly differentiated ERMS with PTCH deletion), eight (22%) had spindle cell RMS (SRMS) (three VGLL2-, one NTRK-, and two (B)RAF-fusions), six (16%) had alveolar RMS (ARMS) (all FOXO1- or PAX3-fusion), two had unclassified RMS, and two poorly differentiated RMS were retrospectively diagnosed as rhabdoid tumors (RT) with loss of INI1 expression. The two RT patients died of rapid disease progression. Five-year event-free (EFS) and overall survival (OS) for RMS were 62% (95%CI, 47-82) and 52% (95%CI, 37-72). Eleven patients (31%) relapsed and four (11%) had primary refractory disease (all ERMS). In univariate analysis, EFS and OS were only associated with histology subtype, with 100% survival of known fusion-positive SRMS. RNA cluster expression showed three main clusters: ARMS, ERMS, and "VGLL2-fusion" cluster, consisting of SRMS and ERMS.

CONCLUSIONS

Biopathology findings from this study support the different prognosis of infantile RMS. New fusion-positive SRMS has a very good outcome which may allow more conservative treatment in the future.

Vascular anomaly imaging mimics and differential diagnoses

Vascular anomalies can be correctly diagnosed in the majority of instances using the combination of clinical history, physical examination and imaging. In certain cases, the clinical work-up may be inconclusive or unavailable to the radiologist, and the imaging findings can be nonspecific, yielding more than one possible diagnosis. In this pictorial essay, we discuss diagnoses that can mimic vascular anomalies and highlight key differentiating imaging features.

Rhabdomyosarcoma diagnosed in the first year of life: Localized, metastatic, and relapsed disease. Outcome data from five trials and one registry of the Cooperative Weichteilsarkom Studiengruppe (CWS)

BACKGROUND

Rhabdomyosarcoma (RMS) diagnosed during the first year of life is reported to have poor outcome. Little is known about treatment and outcome data of relapsed disease (RD).

METHODS

Characteristics, treatment, and outcome of 155 patients ≤ 12 months registered within the Cooperative Weichteilsarkom Studiengruppe (CWS) between 1981 and 2016 were evaluated.

RESULTS

Localized disease (LD) was diagnosed in 144 patients and metastatic disease (MD) in 11. The histological diagnosis was alveolar (RMA) (n = 38, 23/25 examined patients PAX7/3:FOXO1-positive), embryonal (RME) (n = 100), botryoid (n = 10), anaplastic (n = 1), and spindle-cell RMS (n = 6). Multimodal treatment including conventional (age-adjusted) chemotherapy (CHT) (n = 150), resection (n = 137), and radiotherapy (RT) (n = 37) was administered. Complete remission was achieved in 129 of 144 patients with LD. RD occurred in 51 infants at a median age of 1.7 years (range, 0.3-8.8). Sixty-three percent of patients with RMA suffered RD, in contrast to 28% of patients with RME. Relapse treatment consisted of conventional CHT (n = 48), resection (n = 28), and RT (n = 21). The pattern of relapse and best resection were significant prognostic factors for patients with RD (P = 0.000 and P = 0.002). Late effects occurred as secondary malignancies in 6%, long-term toxicity in 21%, and resection-related impairment in 33% of the 105 surviving patients. The 5-year event-free survival and overall survival for infants with initial LD were 51% and 69%, 14% and 14% for patients with initial MD and 39% and 41% for relapsed patients, respectively.

CONCLUSION

Multimodal treatment including microscopically complete resection is strongly recommended to achieve a good prognosis in LD and RD of infants with RMS.

Rhabdomyosarcoma

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children and represents a high-grade neoplasm of skeletal myoblast-like cells. Decades of clinical and basic research have gradually improved our understanding of the pathophysiology of RMS and helped to optimize clinical care. The two major subtypes of RMS, originally characterized on the basis of light microscopic features, are driven by fundamentally different molecular mechanisms and pose distinct clinical challenges. Curative therapy depends on control of the primary tumour, which can arise at many distinct anatomical sites, as well as controlling disseminated disease that is known or assumed to be present in every case. Sophisticated risk stratification for children with RMS incorporates various clinical, pathological and molecular features, and that information is used to guide the application of multifaceted therapy. Such therapy has historically included cytotoxic chemotherapy as well as surgery, ionizing radiation or both. This Primer describes our current understanding of RMS epidemiology, disease susceptibility factors, disease mechanisms and elements of clinical care, including diagnostics, risk-based care of newly diagnosed and relapsed disease and the prevention and management of late effects in survivors. We also outline potential opportunities to further translate new biological insights into improved clinical outcomes.

Uncommon Neonatal Skin Lesions

Certain rashes and cutaneous lesions in a newborn can be clues to more concerning diseases and conditions if recognized and evaluated promptly. Langerhans cell histiocytosis, cutaneous forms of cancer (such as leukemia cutis, neuroblastoma, and rhabdomyosarcoma), developmental abnormalities such as neural tube or spinal dysraphism, and aplasia cutis congenita, nutritional deficiency, and immunodeficiency all have a range of cutaneous findings that will be reviewed herein to guide diagnosis and management. [Pediatr Ann. 2019;48(1):e30-e35.].

Treatment Approach and Outcomes in Infants With Localized Rhabdomyosarcoma: A Report From the Soft Tissue Sarcoma Committee of the Children's Oncology Group

PURPOSE

For infants with localized rhabdomyosarcoma who were enrolled on Children's Oncology Group ARST0331 and ARST0531, local therapy guidelines were provided, but adherence was not mandated because of toxicity concerns. We examined adherence to protocol for local therapy guidelines, treatment variations, and outcomes for these patients.

METHODS

Children aged ≤24 months who were enrolled on ARST0331 and ARST0531 were evaluated. Data were verified through radiologic, surgical, pathologic, and clinical records. Local therapy was assessed for adherence to protocol guidelines, with variations termed "individualized local therapy." The subdistribution hazards model assessed local failure, the Kaplan-Meier product limit method assessed event-free survival (EFS) and overall survival, and the log-rank test was used to evaluate prognostic impact.

RESULTS

The median age of the patients was 14 months, and 124 patients were eligible. Common primary sites were genitourinary (40%), parameningeal (14%), and the extremities (11%). Most patients had unresected disease (group 3, 64%) and embryonal histology (73%). Fifty-eight percent of patients received radiation therapy at a median of week 12 (weeks 1-45). The median radiation dose was 48.6 Gy (30.6-54 Gy). Forty-three percent of patients received individualized local therapy (outside protocol guidelines), typically omission or delay of radiation therapy. Delayed primary excision was performed in 28% at a median of week 14 (weeks 7-34). With a median follow-up of 5.6 years, the 5-year local failure, EFS, and overall survival rates were 24%, 68%, and 82%, respectively. Local failure was significantly higher (35%) in patients receiving individualized local therapy than in patients who received protocol-specified local therapy (16%; P = .02). The site of failure was local in 64% of patients, local and distant in 5%, and distant only in 23%. EFS was significantly higher among patients who were aged 12 to 24 months, had tumors ≤5 cm, had group 1/2 disease, and underwent protocol-specified therapy.

CONCLUSIONS

Local recurrence was the predominant pattern of failure and was more common in those receiving individualized local therapy. De-escalation of effective therapies because of concerns about treatment toxicity should be considered cautiously.

Massive Embryonal Rhabdomyosarcoma of the Hand in an Infant With Metastasis at Birth: Management Dilemma

BACKGROUND

Rhabdomyosarcomas are malignant tumors arising from striated muscle but can be often confused with primitive neuroectodermal tumors and Ewing sarcoma. They are often classified based on age of presentation and histological features. Three major types of rhabdomyosarcomas are embryonal, alveolar, and pleomorphic with characteristic presentations.

METHOD

Here, we present a case of embryonal rhabdomyosarcoma in the hand of a 5-month-old child with lymphatic metastasis, the age, site, and metastasis being unusual feature for this type of rhabdomyosarcoma.

RESULT

The child succumbed to the complications soon after initiation of chemotherapy.

CONCLUSION

Age, site, metastasis at birth and treatment related complications contribute to the poor outcome.

Pediatric soft tissue sarcoma of the limbs: clinical outcome of 97 patients

PURPOSE

Soft tissue sarcomas (STS) of the extremities in children are a heterogeneous group of tumors with a very different prognosis for which optimal treatment remains controversial.

PATIENTS AND METHODS

We retrospectively evaluated 97 patients younger than 15 years old affected by limb soft tissue sarcomas. All cases were histologically revised, and tumor grade was assessed according to the FNLCC system. Thirty-two were rhabdomyosarcoma (RMS) and 65 non-rhabdomyosarcoma (NRMSTS); among these, 40 (61.5%) were grade 3 according to FNLCC classification. Overall survival, local recurrence and distant metastasis were analyzed.

RESULTS

Overall survival was 77.8% at 5 years and 69.7% at 10 years. Among grade 3 tumors, RMS had a worse prognosis over NRSTS. Similarly, tumors larger than 5 cm had a worse prognosis compared to smaller ones. Local recurrence-free survival was 90.7% at 5 years and 87.1% at 10 years with a better local control in grade 3 NRSTS over RMS and in tumors smaller than 2 cm.

CONCLUSION

Children affected by extremities RMS were confirmed to have the worst prognosis, in particular in case of metastasis at presentation. Differently from adult patients, hand and feet locations are frequent site for STS and 2 cm diameter should be taken as cut off for higher risk of LR. Similarly to adulthood STS, grading correlates with prognosis in NRSTS. The identification of prognostic variables should enable risk-adapted therapies to be planned.

Diagnosis and Management of Rhabdomyosarcoma in Children and Adolescents: ICMR Consensus Document

Rhabdomyosarcoma (RMS) is a highly malignant tumor which is thought to originate from the pluripotent mesenchyme. It is the most common soft-tissue sarcoma of childhood. This review article summarizes the recent and older published literature and gives an overview of management of RMS in children. RMS can arise in a wide variety of primary sites, some of which are associated with specific patterns of local invasion, regional lymph nodal spread, therapeutic response and long term outcome, hence requiring physicians to be familiar with site-specific staging and treatment details. Most common primary sites include the head and neck region, genitourinary tract, and extremities. Prognosis for children and adolescents with RMS has recently improved substantially, especially for patients with local or locally extensive disease because of the development of multi-modal therapy incorporating surgery, dose-intensive combination chemotherapy, and radiation therapy. Despite aggressive approaches the outcome for patients who present with metastatic disease remains unsatisfactory. Clinical trials are ongoing to reduce toxicity and improve outcomes of such patients; newer agents in combination are being investigated.

Rhabdomyosarcoma of the maxillofacial region in children and adolescents: Report of 9 cases and literature review

OBJECTIVE

To review clinical presentation, histology, treatment and survival for pediatric maxillofacial rhabdomyosarcoma (RMS) and evaluate the role of surgical treatment.

STUDY DESIGN

Retrospective analysis of medical charts.

METHODS

Files of patients, treated for primary maxillofacial RMS from 1997 to 2016, were examined for clinical presentation, staging, histology, treatment protocol and complications, recurrence and final outcome.

RESULTS

Our cohort included 4 male and 5 female patients (mean age 8.47 years). One tumor, occupying the infratemporal space, was parameningeal; the other 8, located at the mandible (4) or the maxilla/zygomatic bone (4) were non-parameningeal. All patients received chemotherapy preoperatively. Surgery was performed in 7 patients, of whom 4 received postoperative radiotherapy. The histological type was alveolar (5) or embryonal (4). Overall survival hitherto was 66,6%, depending on histology (40% and 100% for the alveolar and embryonal type respectively).

CONCLUSIONS

Pediatric maxillofacial RMS originated mostly from the facial skeleton and most tumors were non-parameningeal. The alveolar type was slightly more common. An individualized multidisciplinary approach combining chemotherapy and local control mostly with surgery and selectively with radiotherapy has proven successful for the treatment of non-orbital, non-parameningeal maxillofacial RMS. Histology was a major treatment determinant and the most important prognostic factor.

Congenital Eyelid Rhabdomyosarcoma

Rhabdomyosarcoma is the most common type of soft tissue sarcoma in children. The authors present a rare case of eyelid rhabdomyosarcoma in a newborn, who was found to have a reddish eyelid tumor in his OD. A mass with a clear margin, confined to the upper eyelid, was revealed using orbital MRI. Intralesional steroids were injected under the impression of a capillary hemangioma and the tumor shrank initially, but grew rapidly later. Therefore, a debulking surgery was performed and the final diagnosis was embryonal rhabdomyosarcoma. After the operation, metastases still occurred despite the treatment with chemotherapy and concurrent radiation. The patient expired at 6 months of age. In an autopsy, a neuroblastoma was incidentally found in his left adrenal gland. Early biopsy may help lead to an early correct diagnosis and avoid metastases in similar cases.

Pediatric Sarcomas

Pediatric sarcomas are a heterogeneous group of tumors accounting for approximately 10% of childhood solid tumors. Treatment is focused on multimodality therapy, which has improved the prognosis over the past two decades. Current regimens focus on decreasing treatment for low-risk patients to decrease the long-term side effects while maximizing therapy for patients with metastatic disease to improve survival. Pediatric sarcomas can be divided into soft tissue sarcomas and osseous tumors. Soft tissue sarcomas are further delineated into rhabdomyosarcomas, which affect young children and nonrhabdomyosarcomas, which are most common in adolescents. The most common bone sarcomas are osteosarcomas and Ewing's sarcoma.

Cost minimization analysis of two treatment regimens for low-risk rhabdomyosarcoma in children: a report from the Children's Oncology Group

BACKGROUND

Recent Children's Oncology Group trials for low-risk rhabdomyosarcoma attempted to reduce therapy while maintaining excellent outcomes. D9602 delivered 45 weeks of outpatient vincristine and dactinomycin (VA) for patients in Subgroup A. ARST0331 reduced the duration of therapy to 22 weeks but added four doses of cyclophosphamide to VA for patients in Subset 1. Failure-free survival was similar. We undertook a cost minimization comparison to help guide future decision-making.

PROCEDURE

Addressing the costs of treatment from the healthcare perspective we modeled a simple decision-analytic model from aggregate clinical trial data. Medical care inputs and probabilities were estimated from trial reports and focused chart review. Costs of radiation, surgery and off-therapy surveillance were excluded. Unit costs were obtained from literature and national reimbursement and inpatient utilization databases and converted to 2012 US dollars. Model uncertainty was assessed with first-order sensitivity analysis.

RESULTS

Direct medical costs were $46,393 for D9602 and $43,261 for ARST0331 respectively, making ARST0331 the less costly strategy. Dactinomycin contributed the most to D9602 total costs but varied with age (42-69%). Chemotherapy administration costs accounted for the largest proportion of ARST0331 total costs (39-57%). ARST0331 incurred fewer costs than D9602 under most alternative distributive models and alternative clinical practice assumptions.

CONCLUSIONS

Cost analysis suggests that ARST0331 may incur fewer costs than D9602 from the healthcare system's perspective. Attention to the services driving the costs provides directions for future efficiency improvements. Future studies should prospectively consider the patient and family's perspective.

What is new in the biology and treatment of pediatric rhabdomyosarcoma?

PURPOSE OF REVIEW

The purpose of this review is to highlight some of the advances in the way we think about rhabdomyosarcoma (RMS). Recent outcome and biological analyses have shifted the risk stratification and treatment paradigms for pediatric RMS.

RECENT FINDINGS

The presence or absence of the FOXO1 translocation is one of the most important prognostic factors in RMS. Future clinical studies will incorporate FOXO1 translocation status within risk stratification criteria. Molecular analyses have identified RAS/NF1, hedgehog, IL-4R, and ALK pathway abnormalities as potential therapeutic targets in RMS. Reductions in systemic therapy are possible, although radiation therapy remains essential to prevent local failures in most patients.

SUMMARY

Although survival for RMS has not improved in recent years, refinement in risk stratification, further understanding of the biological drivers of the disease, and modifications in treatment intensity have set the stage for the next generation of studies in RMS.

A rare case of congenital rhabdomyosarcoma with review of the literature

We present a rare case of rhabdomyosarcoma of lip in a neonate with multiple lesions within the head and necksub site hitherto unreported in the medical literature. This case report also reviews the scant medical literature on neonatal rhabdomyosarcoma.