Comparing adult and pediatric rhabdomyosarcoma in the surveillance, epidemiology and end results program, 1973 to 2005: an analysis of 2,600 patients

Clinicopathological and treatment response characteristics of updated rhabdomyosarcoma histomolecular subtypes: An Asian population-based study

AIM

New histomolecular subtypes of rhabdomyosarcoma have recently been defined but their corresponding clinical characteristics are not well described. Also, these clinical phenotypes vary greatly by age and ethnicity but have not been profiled in Asian populations. Thus, we sought to determine the landscape of rhabdomyosarcoma subtypes in a national Asian cohort and compare clinical characteristics among age groups and molecular subtypes.

METHODS

We performed a retrospective population-based study of all rhabdomyosarcoma patients in Singapore public hospitals from 2004 to 2014 (n = 67), and assigned histomolecular subtypes according to the updated 2020 WHO classification of soft tissue tumors following central pathology review and molecular profiling.

RESULTS

Age-specific prevalence followed a tri-modal peak. There were significantly more embryonal and alveolar (p = 0.032) and genitourinary (non-bladder/prostate) tumors (p = 0.033) among children. Older age was associated with complete resection among spindle cell/sclerosing tumors (p = 0.027), with the omission of chemotherapy among embryonal tumors (p = 0.001), and with poorer survival among embryonal and alveolar tumors (p = 0.026, p = 0.022, respectively). Overall survival differed with stage, group, and surgical resection, adjusted for age group (p = 0.004, p = 0.001, p = 0.004, respectively). Spindle-cell/sclerosing tumors showed an indolent phenotype with a significantly lower incidence of nodal metastasis (p = 0.002), but two of 15 patients with MYOD1 mutations had a contrastingly aggressive disease.

CONCLUSION

Disease and treatment response profiles of rhabdomyosarcoma subtypes vary significantly between adults and children, especially surgical resectability. In our Asian population, poorer outcomes were observed in adults with embryonal and alveolar tumors, while activating mutations influence the behavior of otherwise favorable spindle cell/sclerosing tumors.

Characterization of a pleomorphic rhabdomyosarcoma cell line

Pleomorphic rhabdomyosarcoma (PRMS) is an extremely rare soft tissue tumor with dismal prognosis that has a higher incidence in adults compared to the other RMS subtypes. The unique PRMS cell line BH1522 was established from a pleural effusion of a lung metastasis and the characteristics of this cell line were compared to two embryonal type RMS (ERMS) cell lines. The affected patient had been treated by surgery, several cycles of chemotherapy and thoracoscopy of the lung metastases. Chemosensitivity of the PRMS cell lines was checked using cytotoxicity assays and oncogene-related and phosphoproteins by Western blot arrays. The BH1522 cell line proved to be chemosensitive to conventional chemotherapeutics and the Son of Sevenless 1 homolog (SOS1) inhibitor BAY-293 that inhibited proliferation and suppressed MYC activity. Results of the novel functional BH1522 tests corroborate published tumor sequencing data that demonstrated alterations in receptor tyrosine kinase/MAPK, PI3K/AKT and mutated p53 as suspected drivers of malignant growth.

Myogenesis gone awry: the role of developmental pathways in rhabdomyosarcoma

Rhabdomyosarcoma is a soft-tissue sarcoma that occurs most frequently in pediatric patients and has poor survival rates in patients with recurrent or metastatic disease. There are two major sub-types of RMS: fusion-positive (FP-RMS) and fusion-negative (FN-RMS); with FP-RMS typically containing chromosomal translocations between the PAX3/7-FOXO1 loci. Regardless of subtype, RMS resembles embryonic skeletal muscle as it expresses the myogenic regulatory factors (MRFs), MYOD1 and MYOG. During normal myogenesis, these developmental transcription factors (TFs) orchestrate the formation of terminally differentiated, striated, and multinucleated skeletal muscle. However, in RMS these TFs become dysregulated such that they enable the sustained properties of malignancy. In FP-RMS, the PAX3/7-FOXO1 chromosomal translocation results in restructured chromatin, altering the binding of many MRFs and driving an oncogenic state. In FN-RMS, re-expression of MRFs, as well as other myogenic TFs, blocks terminal differentiation and holds cells in a proliferative, stem-cell-like state. In this review, we delve into the myogenic transcriptional networks that are dysregulated in and contribute to RMS progression. Advances in understanding the mechanisms through which myogenesis becomes stalled in RMS will lead to new tumor-specific therapies that target these aberrantly expressed developmental transcriptional pathways.

Incidence and survival of European adolescents and young adults diagnosed with sarcomas: EUROCARE-6 results

BACKGROUND

Epidemiological data for sarcoma in adolescents and young adults (AYAs) and across age groups are limited. We aim to: 1) update sarcoma incidence, survival, and changes over time in European AYAs; 2) provide an updated comparison of sarcoma survival in AYAs versus children and mature adults.

METHODS

We calculated crude incidence rates (IR) per 100,000 European population per year from 2006 to 2013. Using the period approach, we calculated 5-year relative survival (RS) for the follow-up period 2010-2014. We estimated changes in incidence and survival for bone sarcoma (BS) and soft tissue sarcoma (STS) subtypes in AYAs in the years 2000-2013.

FINDINGS

In European AYAs, the IR was 0.81/100,000 for BS and 1.45/100,000 for STS. Five-year RS was 69 % and 65 % for BS and STS, respectively. Compared to children, AYAs had poorer survival for Ewing sarcoma of bone, synovial sarcoma, Ewing sarcoma of soft tissue and rhabdomyosarcoma. Compared to mature adults, AYAs had higher 5-year RS for all BS and for most of the STS subtypes. In AYAs, incidence increased for a few bone and soft tissue subtypes. Survival increased mainly for BS.

INTERPRETATION

The reason for the better survival observed in AYAs compared to mature adults is probably multifactorial. The limited improvement of STS survival in AYAs may reflect the relative absence of new drugs for STS during the study period. The increase in RS for BS might relate to general improvements in radiological and surgical approaches and radiotherapy techniques.

Adult and pediatric orbital rhabdomyosarcoma: comparison of characteristics and outcomes

INTRODUCTION

Rhabdomyosarcoma (RMS) is a common pediatric orbital malignancy but is extremely rare in adults. This study assesses clinical and radiographic features, management, and outcomes in adult orbital RMS patients with comparison to pediatric patients.

METHODS

A retrospective chart review from 2000-2023 at Bascom Palmer Eye Institute was conducted evaluating patients aged 0 to 100-years-old with biopsy-confirmed orbital RMS. Medical records were reviewed for demographics, clinical features, imaging, histopathology, management, and outcomes. Statistical analysis was conducted with Mann-U Whitney and chi-squared testing.

RESULTS

Twenty-four patients were included, 15 children (mean age 6.4 ± 4.4 years) and 9 adults (35.7 ± 12.4 years). Patients in both groups presented with eyelid edema followed by proptosis with similar symptom duration (p = 0.31). Lesions were frequently located medially and inferiorly in both groups. At presentation, adults had significantly more metastatic disease in addition to bone, extraocular muscle, intracranial, and parameningeal involvement. The most common pediatric RMS subtype was embryonal (80%), whereas most adults were alveolar (77.8%, p = 0.001). Treatment in both groups frequently included chemoradiation. Both groups demonstrated similar local recurrence (p = 0.72), overall survival (p = 0.86), and ophthalmologic sequelae (p = 0.45), although pediatric follow-up duration was notably longer.

CONCLUSIONS

To our knowledge, this study is the largest report of adult orbital RMS from a single institution, highlights key comparisons in features and outcomes between adult and pediatric orbital RMS, and provides an updated literature review. While pediatric and adult orbital RMS clinical presentations are similar, adult disease more often demonstrates aggressive features, including alveolar subtype, local structure involvement, and lower disease-free survival.

Developmental Heterogeneity of Rhabdomyosarcoma

Rhabdomyosarcoma (RMS) is a pediatric embryonal solid tumor and the most common pediatric soft tissue sarcoma. The histology and transcriptome of RMS resemble skeletal muscle progenitor cells that have failed to terminally differentiate. Thus, RMS is typically thought to arise from corrupted skeletal muscle progenitor cells during development. However, RMS can occur in body regions devoid of skeletal muscle, suggesting the potential for nonmyogenic cells of origin. Here, we discuss the interplay between RMS driver mutations and cell(s) of origin with an emphasis on driving location specificity. Additionally, we discuss the mechanisms governing RMS transformation events and tumor heterogeneity through the lens of transcriptional networks and epigenetic control. Finally, we reimagine Waddington's developmental landscape to include a plane of transformation connecting distinct lineage landscapes to more accurately reflect the phenomena observed in pediatric cancers.

Soft tissue tumors of the lower leg, foot and ankle: A cross-sectional observational study analysing 376 cases

Fewer than 5 % of soft tissue sarcomas arise in the foot and ankle. It can be difficult to distinguish between benign and malignant lesions which leads to a delay in diagnosis. Initial inappropriate procedures limit options for limb salvage and increasing rates of local recurrence. Our aim is to improve understanding of the presentation and management of these rare tumors to reduce delays in diagnosis and decrease the occurrence of inappropriate or unwarranted procedures. A prospectively maintained database of 376 new referrals to the West of Scotland regional musculoskeletal oncology service for soft tissue lesions of the foot, ankle, and lower leg over a 10-year period was analysed retrospectively. An assessment was made of patient demographics, presentation, anatomical location, diagnosis, classification, management, and outcomes for all patients. Of all new referrals, 53.5 % were diagnosed with primary benign soft tissue tumors and 16 % with primary malignant soft tissue tumors. The most common primary benign tumor in our population was schwannoma (15.9 %) and primary malignant tumor was undifferentiated sarcoma (26.7 %). In the foot alone, soft tissue sarcomas most commonly occurred in the forefoot (44.4 %). The most common presenting complaints were rest pain and focal swelling. Symptoms were present for on average 7 months prior to referral. Death from disease in sarcomas was 41.7 % over a 10 year follow up period, higher than other body areas. Soft tissue sarcomas in the foot and ankle remain a diagnostic challenge. Local biopsies should only be performed following discussion with an oncology surgeon. We have provided a management protocol in order to reduce the number of inappropriate procedures performed in this group and expedite referral to specialist centres, optimising clinical outcomes and reducing the cost of litigation to healthcare services.

"Update on pediatric primary liver tumors"

Liver masses are common in children, however primary malignant neoplasms are rare, representing only 1% of all pediatric cancers. Hepatocellular neoplasms are the most common primary liver malignancies and hepatoblastoma (HB) is the most frequently diagnosed. The incidence of HB, which is increasing, is approximately of 2 cases per million in the United States, followed by hepatocellular carcinoma (HCC). Pediatric primary liver tumors of mesenchymal origin are less common, except for benign vascular tumors (hemangiomas). Malignant mesenchymal neoplasms represent approximately 10-15% of all, the most common being embryonal sarcoma and malignant rhabdoid tumor. Malignant vascular tumors are rare, but epithelioid hemangioendothelioma (EHE) and angiosarcoma can be seen in children. The development and adoption of consensus diagnostic, therapeutic and risk-stratifying approaches for pediatric patients with malignant liver tumors has been historically challenged by their rarity and by their diverse clinical and histological appearance. On-going collaborative efforts of international consortia including the Children's Oncology Group (COG) in North America, the German Society of Paediatric Oncology and Haematology (GPOH), the Societe Internationale d' Oncologie Pediatrique Liver Tumor Study Group (SIOPEL) in Europe and the Japanese Liver Tumor group (JPLT), have made significant contributions to understanding the clinical and histopathological features, as well as the underlying biology of pediatric liver tumors, in particular HB. A new classification of pediatric liver tumors drafted at the international consensus meeting held in Los Angeles, has been incorporated in the recent WHO classification and is currently used by the PHITT (Paediatric Hepatic Malignancy International Tumour Trial) and other therapeutic protocols. This manuscript provides an overview of salient diagnostic features and updates in classification and molecular characterization for the most common pediatric primary liver neoplasms. It also includes a brief overview of other less common but relevant tumors, which should be considered in the differential diagnosis.

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

III Laryngoscope, 2024.

A comparative analysis of IDH-mutant glioma in pediatric, young adult, and older adult patients

BACKGROUND

The frequency and significance of IDH mutations in glioma across age groups are incompletely understood. We performed a multi-center retrospective age-stratified comparison of patients with IDH-mutant gliomas to identify age-specific differences in clinico-genomic features, treatments, and outcomes.

METHODS

Clinical, histologic, and sequencing data from patients with IDH-mutant, grades 2-4 gliomas, were collected from collaborating institutions between 2013 and 2019. Patients were categorized as pediatric (<19 years), young adult (YA; 19-39 years), or older adult (≥40 years). Clinical presentation, treatment, histologic, and molecular features were compared across age categories using Fisher's exact test or analysis-of-variance. Cox proportional-hazards regression was used to determine the association of age and other covariates with overall (OS) and progression-free survival (PFS).

RESULTS

We identified a cohort of 379 patients (204 YA) with IDH-mutant glioma with clinical data. There were 155 (41%) oligodendrogliomas and 224 (59%) astrocytomas. YA showed significantly shorter PFS and shorter median time-to-malignant transformation (MT) compared to pediatric and adult groups, but no significant OS difference. Adjusting for pathology type, extent of resection, and upfront therapy in multivariable analysis, the YA group was independently prognostic of shorter PFS than pediatric and adult groups. Among astrocytomas, CDK4/6 copy number amplifications were associated with both shorter PFS and shorter OS. Among oligodendrogliomas, PIK3CA and CDKN2A/2B alterations were associated with shorter OS.

CONCLUSIONS

IDH-mutant glioma YA patients had significantly shorter PFS and time to MT but did not differ in OS compared to pediatric and adult groups. Treatment approaches varied significantly by patient age and warrant further study as addressable age-associated outcome drivers.

Incidence and patterns of lymph node metastases in head and neck rhabdomyosarcoma: One-institution study

INTRODUCTION

Head and neck rhabdomyosarcoma (HNRMS) is an aggressive malignant soft tissue tumor that easily develops lymph node metastasis (LNM) and distant metastasis. No literature investigates the pattern of LNM in HNRMS.

METHODS

Ninety-five consecutive patients with HNRMS newly diagnosed at one institution between November 2011 and July 2023 were retrospectively reviewed. All the patients underwent head and neck contrast-enhanced MRI and/or CT, PET-CT if necessary. The associations between LNMs and clinical characteristics and histopathological parameters were discovered.

RESULTS

44.2% of patients had evidence of LNM at diagnosis, and the most common LNM occurred in the ipsilateral retropharyngeal space. The primary tumor metastasizes to the retropharyngeal space, and then next to level II is the most common LN drainage basin. In multivariate analysis, only distant metastasis determines the prognosis, other than LN status.

CONCLUSIONS

LNM has a high incidence in HNRMS and rarely causes contralateral metastasis for localized lesions or skip metastasis.

Epidemiology, trends, and survival of ocular and orbital rhabdomyosarcoma: a nationwide study in the USA (1996-2018) : Ocular and orbital rhabdomyosarcoma in the USA

BACKGROUND

Rhabdomyosarcoma (RMS) is a rare malignancy that affects both children and young adults. Therefore, the current incidence and mortality rates of ocular and orbital rhabdomyosarcoma (ORMS) need to be clarified. We aimed to explore the epidemiology, trends, and survival outcomes of ORMS in the United States population spanning over two decades, from 1996 to 2018.

METHODS

We retrospectively reviewed 92,633 patients with ocular and adnexal malignancies and identified 640 ORMS cases from the North American Association of National Cancer Registries. Demographics, tumor characteristics, treatment modalities, and survival outcomes were analyzed.

RESULTS

Most ORMS cases (71.7%) were reported in children aged-0-9 years. The age-adjusted incidence of ORMS was 0.1 per million population (ppm), with males demonstrating a higher incidence (0.12 ppm) than females (0.09 ppm). Whites had the highest incidence rate (0.11 ppm). Embryonal ORMS is the most common histological subtype. The incidence trend over the 22-year study period revealed a decline in ORMS from 0.124 to 0.076, in contrast with the incidence of whole-body RMS, which showed an insignificant increase. The 5-year relative survival rates of patients with ORMS were 89.7%, whereas the 10-year relative survival rate was 87.2%. The 5-year relative survival trend for ORMS increased but was insignificant.

CONCLUSIONS

ORMS primarily affects young children and males, with the embryonal subtype being the most common. Despite the declining incidence, survival rates have remained stable, underscoring the need for further research on the risk factors, diagnostics, and management strategies to improve patient outcomes.

KEY MESSAGES

What is known Ocular and Orbital Rhabdomyosarcoma (ORMS) predominantly affects children, especially males, and is the most frequent primary tumor in the  orbit during childhood. The embryonal subtype is the most common histological subtype of ORMS. What is new A significant decline in the incidence of ORMS was observed over the 22-year study period, in contrast to the overall incidence of whole-body  rhabdomyosarcoma. It has a characteristic bigeminal distribution with a peak at 3-4 and another at 6  years. Patients receiving combined treatment modalities showed improved survival  rates, while those undergoing surgery alone had poorer outcomes. Despite advancements in treatment, there has been no significant increase in  the 5-year relative survival trends for ORMS.

Antimicrobial Properties and Therapeutic Potential of Bioactive Compounds in Nigella sativa: A Review

Nigella sativa (N. sativa; Ranunculaceae), commonly referred to as black cumin, is one of the most widely used medicinal plants worldwide, with its seeds having numerous applications in the pharmaceutical and food industries. With the emergence of antibiotic resistance in pathogens as an important health challenge, the need for alternative microbe-inhibitory agents is on the rise, whereby black cumin has gained considerable attention from researchers for its strong antimicrobial characteristics owing to its high content in a wide range of bioactive compounds, including thymoquinone, nigellimine, nigellidine, quercetin, and O-cymene. Particularly, thymoquinone increases the levels of antioxidant enzymes that counter oxidative stress in the liver. Additionally, the essential oil in N. sativa seeds effectively inhibits intestinal parasites and shows moderate activity against some bacteria, including Bacillus subtilis and Staphylococcus aureus. Thymoquinone exhibits minimum inhibitory concentrations (MICs) of 8-16 μg/mL against methicillin-resistant Staphylococcus aureus (MRSA) and exhibits MIC 0.25 µg/mL against drug-resistant mycobacteria. Similarly, quercetin shows a MIC of 2 mg/mL against oral pathogens, such as Streptococcus mutans and Lactobacillus acidophilus. Furthermore, endophytic fungi isolated from N. sativa have demonstrated antibacterial activity. Therefore, N. sativa is a valuable medicinal plant with potential for medicinal and food-related applications. In-depth exploration of the corresponding therapeutic potential and scope of industrial application warrants further research.

The Other Site of Rhabdomyosarcoma

BACKGROUND

Rhabdomyosarcoma (RMS) is a rare malignant soft tissue sarcoma (STS), accounting for almost 50% of pediatric STSs. Due to its heterogeneity, RMS presents challenges in diagnosis and treatment, with prognosis varying depending on multiple factors. Tumors localized in the other site (OTH)-including the paraspinal, perianal, thoracic, abdominal, pelvic, and perineal regions-are generally classified as unfavorable. This study assesses the clinical features and prognoses of RMS in OTH locations depending on its site of origin.

METHODS

An explorative analysis of RMS cases from the SEER 17 database 2000-2020 was conducted. Patients of all ages with histologically confirmed RMS as primary malignant disease classified under OTH, were included. OTH was categorized in four granular site classifications. Overall survival (OS) and disease-specific survival (DSS) were analyzed using Kaplan-Meier estimators. Factors independently influencing survival, including a site classification model presented in this study, were identified through Cox regression analysis.

RESULTS

Out of 4168 patients with RMS, 990 cases of RMS with the OTH site met the inclusion criteria. The median age was 16 years. The predominant histological subtypes were embryonal (33.0%) and alveolar (25.5%). Most tumors were ≥ 5 cm (median 9 cm) and located primarily in the pelvic region (41.5%). The 3-, 5-, and 10-year OS rates were 45.4% ± 3.332 (95% CI), 40.7 ± 3.332, and 38.6% ± 3.332, respectively, while DSS rates were 43.3% ± 3.136 (95% CI), 38.3% ± 3.136, and 35.1% ± 3.332. In the multivariate analysis age, histological type, site in a granular categorization, stage, regional lymph node examination, and regional lymph node involvement (pathologically proven) were independently associated with survival. Through both univariate and multivariate analyses, an OTH favorable group could be established. The OTH favorable group consists of the anal region, gallbladder and biliary tract, and breast.

CONCLUSION

RMS in OTH shows significant differences in prognosis, putting the current categorization as unfavorable into question and making a more detailed classification necessary. Furthermore, pathological regional lymph node assessment is specifically in the OTH localization recommended.

Rhabdomyosarcoma of the skull with EWSR1 fusion and ALK and cytokeratin expression: a case report

Rhabdomyosarcoma (RMS) comprises of heterogeneous group of neoplasms that occasionally express epithelial markers on immunohistochemistry (IHC). We herein report the case of a patient who developed RMS of the skull with EWSR1 fusion and anaplastic lymphoma kinase (ALK) and cytokeratin expression as cytomorphologic features. A 40-year-old man presented with a mass in his forehead. Surgical resection was performed, during which intraoperative frozen specimens were obtained. Squash cytology showed scattered or clustered spindle and epithelioid cells. IHC revealed that the resected tumor cells were positive for desmin, MyoD1, cytokeratin AE1/ AE3, and ALK. Although EWSR1 rearrangement was identified on fluorescence in situ hybridization, ALK, and TFCP2 rearrangement were not noted. Despite providing adjuvant chemoradiation therapy, the patient died of tumor progression 10 months after diagnosis. We emphasize that a subset of RMS can express cytokeratin and show characteristic histomorphology, implying the need for specific molecular examination.

The molecular conversations of sarcomas: exosomal non-coding RNAs in tumor's biology and their translational prospects

Exosomes mediate cell-to-cell crosstalk involving a variety of biomolecules through an intricate signaling network. In recent years, the pivotal role of exosomes and their non-coding RNAs cargo in the development and progression of several cancer types clearly emerged. In particular, tumor bulk and its microenvironment co-evolve through cellular communications where these nanosized extracellular vesicles are among the most relevant actors. Knowledge about the cellular, and molecular mechanisms involved in these communications will pave the way for novel exosome-based delivery of therapeutic RNAs as well as innovative prognostic/diagnostic tools. Despite the valuable therapeutic potential and clinical relevance of exosomes, their role on sarcoma has been vaguely reported because the rarity and high heterogeneity of this type of cancer. Here, we dissected the scientific literature to unravel the multifaceted role of exosomal non-coding RNAs as mediator of cell-to-cell communications in the sarcoma subtypes.

Embryonal and alveolar rhabdomyosarcoma in adolescents/young adults, adults and older adults: a population-based cohort study

BACKGROUND

The clinical characteristics, outcomes, and prognostic factors of adult embryonal rhabdomyosarcomas (ERMS) and alveolar rhabdomyosarcomas (ARMS), particularly the differences among adolescents/young adults (AYA), adults, and older adults, remain unclear. We assessed the clinicopathological features and survival outcomes of adult patients with ERMS and ARMS in Japan and to compare these features among AYA, adult, and older adult patients.

METHODS

We retrospectively analyzed data from the Bone and Soft Tissue Tumor Registry of Japan and enrolled patients aged ≥15 years with ERMS and ARMS. Disease-specific overall survival (DOS) was estimated using the Kaplan-Meier method, and a Cox regression model was used to identify prognostic factors.

RESULTS

Among 184 patients with ERMS and ARMS (median age, 27 years; interquartile range, 18-49 years), a high rate of distant and regional nodal metastases was initially observed in 65 (35%) and 66 (36%) cases, respectively. Older age and distant metastasis at first presentation were statistically poor prognostic factors, and histological subtype and site of tumor origin were not associated with DOS. In patients with localized ERMS and ARMS, older age and nodal metastasis were poor prognostic factors; the 5-year DOS rates of patients with and without nodal metastasis were 23% and 72%, respectively.

CONCLUSIONS

Older patients with rhabdomyosarcoma had a dismal prognosis, and distant metastasis was a poor prognostic factor. The prognostic factors differed between adult and pediatric patients with rhabdomyosarcoma; biological analyses, such as genome analysis of adult rhabdomyosarcoma and clinical trials with pediatric oncologists, are needed to improve the prognosis of adult rhabdomyosarcoma.

Pediatric Orbital and Skull Base Pathology

Pediatric orbital and skull base pathologies encompass a spectrum of inflammatory, sporadic, syndromic, and neoplastic processes that require a broad and complex clinical approach for both medical and surgical treatment. Given their complexity and often multicompartment involvement, a multidisciplinary approach for diagnosis, patient and family counseling, and ultimately treatment provides the best patient satisfaction and clinical outcomes. Advances in minimally invasive surgical approaches, including endoscopic endonasal and transorbital approaches allows for more targeted surgical approaches through smaller corridors beyond more classic transcranial or transracial approaches.

Rare Glottic Pleomorphic Rhabdomyosarcoma: A Case Report with Review of Literature

Rhabdomyosarcoma (RMS) is commonly reported in children and very rarely in adults. Laryngeal RMS is a rare but extremely aggressive malignancy with a high mortality rate. Surgery followed by postoperative radiotherapy is the preferred treatment. The use of chemotherapy is debatable. This report highlights a case of rare pleomorphic rhabdomyosarcoma of glottis in a 67-year-old male who presented with hoarseness and a description of its management.

Comments and illustrations of the European Federation of Societies for Ultrasound in Medicine contrast-enhanced ultrasound guidelines: Multiparametric imaging and EUS-guided sampling in rare pancreatic tumors. Benign mesenchymal pancreatic tumors

The focus of the review is on primary benign mesenchymal pancreatic tumors and their imaging appearance. These tumors are extremely rare. Usually, they are not diagnosed until postoperative histology is available, and so even benign tumors have undergone extensive pancreatic resection. The very limited data on abdominal and EUS findings including contrast-enhanced techniques of these pancreatic lesions are summarized here. Case reports will be presented for some of these rare tumors with application of modern ultrasound and endosonographic techniques.

The role of radiotherapy in multimodal treatment of non-rhabdomyosarcoma soft tissue sarcomas in children: A real life report from a tertiary center

OBJECTIVE

The current treatment of pediatric non-rhabdomyosarcoma soft tissue sarcomas (NRSTS) is a multimodal risk-based approach. Today, smaller fields and lower doses of radiotherapy (RT) have become standard. In this study, it was aimed to evaluate the treatment outcomes and toxicity profile in children with NRSTS that received RT as a part of multimodal therapy.

METHODS

Twenty-nine patients with pediatric NRSTS treated with neoadjuvant or adjuvant RT between 1998 and 2022 were evaluated retrospectively. Kaplan-Meier method was used for survival analyses.

RESULTS

Median follow-up was 36 months (range, 6-291 months). The median neoadjuvant and adjuvant RT doses were 50 Gy (range, 45-66 Gy) and 54 Gy (45-66 Gy), respectively. During follow-up, six (21%) patients developed a local recurrence and 10 (35%) had distant metastasis. The 5-year local control, overall survival (OS), local recurrence-free survival, and distant metastasis-free survival rate was 79%, 67%, 59%, and 61%, respectively. In multivariate analysis, a ≤5-cm tumor, gross tumor resection, Children's Oncology Group (COG) low-risk group, and absence of neoadjuvant chemotherapy were independent favorable prognostic factors for OS. Severe (≥ grade 3) late toxicity was observed in 6 (20%) patients.

CONCLUSIONS

RT is a crucial component in the multimodal risk-based treatment approach for pediatric NRSTS. However, late toxicity rates are still high and should be improved. Patients with a ≤5-cm tumor, COG low-risk group and treated with gross tumor resection have increased survival rates.

Wnt/β-Catenin Signaling Pathway in Pediatric Tumors: Implications for Diagnosis and Treatment

The evolutionarily conserved Wnt signaling has a significant and diverse role in maintaining cell homeostasis and tissue maintenance. It is necessary in the regulation of crucial biological functions such as embryonal development, proliferation, differentiation, cell fate, and stem cell pluripotency. The deregulation of Wnt/β-catenin signaling often leads to various diseases, including cancer and non-cancer diseases. The role of Wnt/β-catenin signaling in adult tumors has been extensively studied in literature. Although the Wnt signaling pathway has been well explored and recognized to play a role in the initiation and progression of cancer, there is still a lack of understanding on how it affects pediatric tumors. This review discusses the recent developments of this signaling pathway in pediatric tumors. We also focus on understanding how different types of variations in Wnt signaling pathway contribute to cancer development and provide an insight of tissue specific mutations that lead to clinical progression of these tumors.

A Case of Alveolar Rhabdomyosarcoma of the Nasal Cavity in an Adult: An Unusual Location

Rhabdomyosarcoma is a common soft tissue tumor in children but rare in adults. Alveolar rhabdomyosarcoma represents a subtype of rhabdomyosarcoma, extremely rare in adults, especially within the nasal cavities. Therapeutic protocols for adults are often based on those used in pediatric cases. We present the case of a 56-year-old female patient with a history of breast cancer who developed alveolar rhabdomyosarcoma of the nasal cavity, stage III, managed initially with chemotherapy resulting in partial response. Subsequently, the patient underwent concomitant chemoradiotherapy. The clinical course was marked by local remission with metastatic progression after 18 months. Alveolar rhabdomyosarcoma is uncommon in adults, and its therapeutic management remains non-standardized. However, it is typically based on initial chemotherapy followed by local treatment. Despite therapeutic advances, the prognosis remains poor.

Surgery for adult head and neck rhabdomyosarcoma: A retrospective report from one institution

KEY POINTS

Surgery in adults with head and neck rhabdomyosarcoma does not improve survival rates. Surgery should be performed deliberately and focused on the timing of combined treatment modality. Adult head and neck rhabdomyosarcoma benefits from salvage surgery following chemoradiotherapy.

Case report: Lymph node metastasis of pelvic alveolar rhabdomyosarcoma diagnosed by fine needle aspiration cytology

Rhabdomyosarcoma (RMS) is a common soft tissue malignant tumor, especially in young patients. Alveolar rhabdomyosarcoma (ARMS) is a subtype of RMS that is prevalent in adolescents. This malignant tumor usually develops in the extremities and can also involve the trunk, perineum, and pelvis. Now, we report a rare case of pelvic lymph node metastatic alveolar RMS in a young patient, which was determined by fine needle aspiration cytology (FNAC). To the best of our knowledge, this is the first case in which the definite diagnosis of ARMS was initially made by FNAC.

Comments and illustrations of the European Federation of Societies for Ultrasound in Medicine contrast-enhanced ultrasonography guidelines: multiparametric imaging and EUS-guided sampling in rare pancreatic tumors. Mesenchymal pancreatic tumors of intermediate biological behaviour

The focus of the review is on mesenchymal pancreatic tumors with intermediate biological behavior and their imaging appearance. Similar to benign and malignant mesenchymal pancreatic tumors, these tumors are extremely rare. The diagnosis is often confirmed only by postoperative histology. The very limited data on abdominal ultrasound and EUS findings including contrast-enhanced techniques of these pancreatic lesions are summarized here.

Spontaneous tumor lysis syndrome in an adult with alveolar rhabdomyosarcoma: a challenging diagnosis

Tumor lysis syndrome (TLS) is an oncological emergency characterized by metabolic and electrolyte imbalances associated with the rapid destruction of tumor cells. It is commonly recognized when cytotoxic treatment for hematological malignancies is initiated. Spontaneous TLS with solid tumors like rhabdomyosarcoma (RMS) is exceedingly rare. It has been noted that the highest incidence of this tumor occurs in individuals under the age of 20 years, with an incidence rate of 4.4 cases per 1 million. Here, we present the case of a 22-year-old male who presented with spontaneous clinical TLS. A computed tomography (CT) scan revealed a large pelvic mass, diffuse lymphadenopathy, and infiltration of the ocular muscles. Subsequently, a biopsy was conducted, and the histopathological results indicated alveolar rhabdomyosarcoma. Our literature review revealed five cases of spontaneous TLS caused by RMS, with our patient being the only adult among all published cases.

Prognostic factors and treatment outcomes in patients with pleomorphic rhabdomyosarcoma: a population-based cohort study

BACKGROUND

Pleomorphic rhabdomyosarcoma is a rare sarcoma in adults. The clinical characteristics, outcomes and prognostic factors associated with pleomorphic rhabdomyosarcoma remain unclear.

METHODS

We retrospectively analyzed data from the Bone and Soft Tissue Tumor Registry of Japan, and enrolled patients with pleomorphic rhabdomyosarcoma. Disease-specific overall survival, local recurrence-free survival and distant metastasis-free survival were estimated using the Kaplan-Meier method; Cox regression model was used to identify prognostic factors.

RESULTS

In total, 182 patients with pleomorphic rhabdomyosarcoma were included. Median age was 63 (range 20-95) years. The lower extremity (48%) was the most frequent tumor origin site, while head and neck were rare (4%). A total of 43 patients (24%) had distant or regional nodal metastases at first presentation. In all cases, the 2-year and 5-year survival rates were 66.3% and 54.1%, respectively. Distant metastasis was a significant poor prognostic factor (Hazard ratio 6.65; 95% confidence intervals, 3.00-14.75, P < 0.0001), with median survival of such patients being 9.4 (95% confidence intervals: 5.3-12.2) months. In 134 localized cases, the 2-year and 5-year survival rates were 91.5% and 68.3%, respectively. Large tumor size and older age were associated with poorer prognosis. Through data from localized and locally curative cases extracted and adjusted by propensity score matching, we found that perioperative chemotherapy did not improve disease-specific overall survival, distant metastasis-free survival or local recurrence-free survival.

CONCLUSIONS

Clinical characteristics and outcomes of pleomorphic rhabdomyosarcoma are similar to those of other high-grade soft tissue sarcomas. Pleomorphic rhabdomyosarcoma may be less chemosensitive, and a strategy other than the standard cytotoxic chemotherapy is required to improve its prognosis.

Adolescents and young adults with rhabdomyosarcoma: A report from the Soft Tissue Sarcoma Committee of the Children's Oncology Group

INTRODUCTION

The impact of established prognostic factors on survival outcomes for childhood rhabdomyosarcoma (RMS) have not been well described in the adolescent and young adult (AYA) RMS patient population.

METHODS

This is a retrospective analysis of patients with newly diagnosed RMS enrolled between 1997 and 2016 on seven previously reported Children's Oncology Group (COG) clinical trials. Demographics, clinical features, treatment details, and outcome data were collected. Five-year event-free survival (EFS) and overall survival (OS) were estimated for patients diagnosed at age 15-39 years and those diagnosed under age 15 years using the Kaplan-Meier method. Log-rank test was used to compare prognostic factors for EFS and OS. Factors significant in the univariable analysis were included in a Cox proportional hazards regression model. Nonsignificant covariates were removed from the multiple regression model.

RESULTS

Total 2151 patients including 402 AYAs were analyzed. AYAs were more likely to present with primary tumors ≥5 cm in size, metastatic disease, alveolar histology, and have FOXO1 fusions compared to children. Five-year EFS for the AYA cohort was 44.2% versus 67% for children (p < .001), and 5-year OS was 52% for the AYA cohort versus 78% for children (p < .001). Multivariable analysis revealed tumor site, size and invasiveness, clinical group, and histology were prognostic in AYAs.

CONCLUSION

AYAs with RMS have a poorer prognosis compared to younger children due to multiple factors. Further research focused on AYAs to better understand RMS biology and improve treatments is critical to improve survival.

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.

Adult head and neck rhabdomyosarcoma: radiotherapy- based treatment, outcomes, and predictors of survival

BACKGROUND

Adult head and neck rhabdomyosarcoma (HNRMS) is an exceptionally rare malignancy, and there is a paucity of data and research dedicated to understanding its characteristics and management in adult populations. This study aimed to assess the outcomes and identify survival predictors in adult HNRMS.

METHODS

We retrospectively evaluated 42 adult patients (> 16 years) with HNRMS who received radiotherapy (RT)-based treatment at our institute between 2008 and 2022. We analysed the clinical characteristics and prognosis of these patients, including the locoregional recurrence-free survival (LRFS), progression-free survival (PFS), and overall survival (OS), using the Kaplan-Meier method. The chi-square and Fisher's exact tests were used to analyse differences between groups for dichotomous and categorical variables, respectively. Survival rates were calculated using the Kaplan-Meier method. Prognostic variables were assessed through univariate Cox analyses.

RESULTS

The median patient age was 28 years (range, 16-82 years). Alveolar RMS was the most common histological type, observed in 21 patients (50.0%), followed by embryonal in 16 patients (38.1%). The anatomic sites of origin were orbital in one (2.4%), parameningeal in 26 (61.9%), and non-orbital/non-parameningeal in 15 (35.7%) patients. Nineteen patients (45.2%) had regional lymph node metastasis, and five patients (11.9%) presented with distant metastatic disease. Distant metastasis (n = 17) was the primary cause of treatment failure. At a median follow-up of 47.0 months, the 5-year LRFS, PFS, and OS rates were 69.0%, 39.7%, and 41.0%, respectively. Univariate analysis revealed that tumour size, lymph node involvement, and the local treatment pattern (surgery and RT vs. RT alone) were significant predictors of survival.

CONCLUSIONS

The main failure pattern in patients with HNRMS receiving RT-based treatment was distant metastasis. Tumour size > 5 cm and lymph node involvement were predictors of worse LRFS. Multimodality local treatment, combining surgery and RT, is effective and provides survival benefits.

Management of a pure uterine corpus rhabdomyosarcoma in a postmenopausal patient: A rare case report and review of the literature

Key Clinical Message

Rhabdomyosarcoma of the female genital tract often involves the vagina and cervix. It usually occurs in infants and children. Such tumors are uncommon in the uterus, especially in adults. Treatment options are based on studies of younger individuals.

Abstract

Rhabdomyosarcoma (RMS) is a malignant mesenchymal neoplasm with a tendency to differentiate into skeletal muscle cells. RMS is an aggressive tumor that tends to develop in children and younger patients. A vast majority of genital tract RMSs occur in the vagina and cervix. Such tumors rarely occur in adults. Usually, these tumors either occur as a component of a biphasic uterine tumor (carcinosarcoma or adenosarcoma) or can be a pure heterologous tumor. Pure uterine RMSs are extremely rare in adult patients and difficult to diagnose. Accurate diagnosis of these tumors depends on precise histopathological evaluation. The present report describes a rare case of embryonal RMS of the uterus in a postmenopausal female and explores the most recent literature. The aim is to strengthen the existing literature and aid clinicians in the management of similar cases. A 64-year-old postmenopausal female presented with a history of abdominal pain associated with abdominal distension, per vaginal bleeding, and foul-smelling discharge for 6 months. A transabdominal ultrasound revealed a bulky uterus with a well-circumscribed heterogeneous lesion. Histopathology confirmed the diagnosis of high-grade embryonal RMS within the corpus region of the uterus. A total abdominal hysterectomy with bilateral salpingo-oophorectomy was performed, followed by adjuvant chemotherapy to prevent relapse of the disease. Six months after oncological care has passed, the patient remains symptoms-free without evidence of recurrence or metastasis.

Comments and illustrations of the European Federation of Societies for Ultrasound in Medicine guidelines: Rare pancreatic tumors, ultrasound and contrast-enhanced ultrasound features-Malignant mesenchymal tumors

Rare malignant mesenchymal pancreatic tumors are systematized and reported in this review. The focus is on the appearance on imaging. The present overview summarizes the data and shows that not every pancreatic tumor corresponds to the most common entities of ductal adenocarcinoma or neuroendocrine tumor.

Rhabdomyosarcoma in Adults: De Novo or Conversion From Non-seminomas?

Rhabdomyosarcoma (RMS) is a highly sporadic, very aggressive, and fatal soft tissue tumor in adults. Although more common and treatable in the pediatric population, the occurrence of pleomorphic RMS in adults has a low incidence. Hence, it is not easy to treat. Surgery is the primary definitive treatment, along with radiation therapy, while adjuvant chemotherapy has recently gained popularity. We present an infrequent case of RMS in a patient with a recent history of mixed non-seminomatous germ-cell tumor testicular cancer. Therefore, it was challenging to treat the RMS as a new malignancy or as a recurrence of non-seminomatous testicular cancer. Our patient passed away, unfortunately, but we hope this case can help the minimal data in this regard in order to save more lives in the future.

Frontline and Relapsed Rhabdomyosarcoma (FaR-RMS) Clinical Trial: A Report from the European Paediatric Soft Tissue Sarcoma Study Group (EpSSG)

The Frontline and Relapsed Rhabdomyosarcoma (FaR-RMS) clinical trial is an overarching, multinational study for children and adults with rhabdomyosarcoma (RMS). The trial, developed by the European Soft Tissue Sarcoma Study Group (EpSSG), incorporates multiple different research questions within a multistage design with a focus on (i) novel regimens for poor prognostic subgroups, (ii) optimal duration of maintenance chemotherapy, and (iii) optimal use of radiotherapy for local control and widespread metastatic disease. Additional sub-studies focusing on biological risk stratification, use of imaging modalities, including [18F]FDG PET-CT and diffusion-weighted MRI imaging (DWI) as prognostic markers, and impact of therapy on quality of life are described. This paper forms part of a Special Issue on rhabdomyosarcoma and outlines the study background, rationale for randomisations and sub-studies, design, and plans for utilisation and dissemination of results.

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.

Pediatric oncology drug development and dosage optimization

Oncology drug discovery and development has always been an area facing many challenges. Phase 1 oncology studies are typically small, open-label, sequential studies enrolling a small sample of adult patients (i.e., 3-6 patients/cohort) in dose escalation. Pediatric evaluations typically lag behind the adult development program. The pediatric starting dose is traditionally referenced on the recommended phase 2 dose in adults with the incorporation of body size scaling. The size of the study is also small and dependent upon the prevalence of the disease in the pediatric population. Similar to adult development, the dose is escalated or de-escalated until reaching the maximum tolerated dose (MTD) that also provides desired biological activities or efficacy. The escalation steps and identification of MTD are often rule-based and do not incorporate all the available information, such as pharmacokinetic (PK), pharmacodynamic (PD), tolerability and efficacy data. Therefore, it is doubtful if the MTD approach is optimal to determine the dosage. Hence, it is important to evaluate whether there is an optimal dosage below the MTD, especially considering the emerging complexity of combination therapies and the long-term tolerability and safety of the treatments. Identification of an optimal dosage is also vital not only for adult patients but for pediatric populations as well. Dosage-finding is much more challenging for pediatric populations due to the limited patient population and differences among the pediatric age range in terms of maturation and ontogeny that could impact PK. Many sponsors defer the pediatric strategy as they are often perplexed by the challenges presented by pediatric oncology drug development (model of action relevancy to pediatric population, budget, timeline and regulatory requirements). This leads to a limited number of approved drugs for pediatric oncology patients. This review article provides the current regulatory landscape, incentives and how they impact pediatric drug discovery and development. We also consider different pediatric cancers and potential clinical trial challenges/opportunities when designing pediatric clinical trials. An outline of how quantitative methods such as pharmacometrics/modelling & simulation can support the dosage-finding and justification is also included. Finally, we provide some reflections that we consider helpful to accelerate pediatric drug discovery and development.

Oral rhabdomyosarcoma, a rare malignant tumor mimicking an endodontic-periodontal lesion in an adult patient: a case report

BACKGROUND

According to previous research, 2.8% of lesions clinically identified as endodontic pathosis were ultimately diagnosed as non-endodontic periapical lesions via histopathology, and 3.7% of these non-endodontic periapical lesions were malignant neoplasms. Rhabdomyosarcoma, a malignant tumor most commonly observed in children, is uncommon in the oral cavity.

CASE PRESENTATION

This is a report of a rare case of embryonal rhabdomyosarcoma in a 41-year-old female, in which the lesion was in the maxillary gingiva. The biopsy reports confirmed the diagnosis of embryonal rhabdomyosarcoma. The wide excision of the tumor, free flap reconstruction, chemotherapy, and radiotherapy were performed. Clinical, radiological, and histopathological and management aspects of the neoplasm were also discussed.

CONCLUSIONS

This case report aimed to create awareness that rhabdomyosarcoma is one of the differential diagnoses of periapical lesions.

BOTRROID Embryonal Rhabdomyosarcoma with Uterine Cervix in a Postmenopausal Woman: An Unusual Case Report

Rhabdomyosarcoma (RMS) is one of the most common soft-tissue sarcomas that engage the embryonal skeletal muscle cells as the female reproductive tract. Embryonal RMS (ERMS) is the most prevalent subtype of RMS in the female genital tract. Botryoid RMS is a rapidly growing rare malignancy and a polypoid variant of ERMS that occurs in childhood and constituting approximately 3% of all RMSs among young children and 1% among adolescents and young adults. A 50 year old menopause woman who had been vaginal discharge and bleeding for about 2 years without dysuria, dyspareunia, or postcuital bleeding was informed consent for presenting. A vaginal examination, pathology examination, sonography, magnetic resonance imaging, immunohistochemistry, surgery and radical hysterectomy, radiation therapy, and two sessions of brachytherapy were performed. After 22 months of follow-up, the patient had no evidence of recurrence or any problem in sexual activity. Oncological surgical treatment based on the carcinoma site and adjuvant chemotherapy is helpful for the treatment of RMS. However, applying the standard treatment guidelines is essential, although it is very scarce and difficult.

18F-fluorodeoxyglucose Positron Emission Tomography/Computed Tomography and 68Ga-prostate-specific Membrane Antigen Positron Emission Tomography/Computed Tomography Imaging in the Evaluation of Rare Entity Adult Embryonal Rhabdomyosarcoma of Prostate

A 21-year-old male with embryonal rhabdomyosarcoma of the prostate was referred for 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) and 68Ga-prostate-specific membrane antigen (PSMA) PET/CT for initial disease staging. The PET scans revealed hypermetabolic and PSMA expressing lobulated mass involving both lobes of the prostate and weakly metabolic and PSMA expressing few bilateral pararectal and external iliac nodes, multiple bilateral lung nodules scattered over the lung parenchyma and multiple bone marrow lesions in both axial and appendicular skeleton. Magnetic resonance imaging prostate showed gross prostatomegaly with large lobulated T2 hyperintense heterogeneously enhancing mass lesion showing restricted diffusion, involving both lobes of the prostate with extraprostatic spread along anterior, posterior, and left lateral margins with evidence of lymph nodal and osseous metastases. The demonstration of increased uptake of 18F-FDG and 68Ga-PSMA in the primary as well as bilateral pararectal and external iliac nodes, multiple bilateral lung nodules, and multiple bone marrow lesions in both axial and appendicular skeleton indicates a potential role of 18F-FDG PET/CT and 68Ga-PSMA PET/CT in disease staging in this rare aggressive tumor of the prostate.

Rhabdomyosarcoma: Current Therapy, Challenges, and Future Approaches to Treatment Strategies

Rhabdomyosarcoma is a rare cancer arising in skeletal muscle that typically impacts children and young adults. It is a worldwide challenge in child health as treatment outcomes for metastatic and recurrent disease still pose a major concern for both basic and clinical scientists. The treatment strategies for rhabdomyosarcoma include multi-agent chemotherapies after surgical resection with or without ionization radiotherapy. In this comprehensive review, we first provide a detailed clinical understanding of rhabdomyosarcoma including its classification and subtypes, diagnosis, and treatment strategies. Later, we focus on chemotherapy strategies for this childhood sarcoma and discuss the impact of three mechanisms that are involved in the chemotherapy response including apoptosis, macro-autophagy, and the unfolded protein response. Finally, we discuss in vivo mouse and zebrafish models and in vitro three-dimensional bioengineering models of rhabdomyosarcoma to screen future therapeutic approaches and promote muscle regeneration.

Small bowel metastasis from embryonal rhabdomyosarcoma of the extremity- a case report

Rhabdomyosarcoma is the most common soft tissue tumour in children and adolescents, but extremely rare in adults with comparatively worse outcomes. Metastatic disease is not uncommon, but intra-abdominal metastases are exceedingly rare. We report an unusual case of ileal metastases from an upper extremity rhabdomyosarcoma in a 17-year-old male who presented with abdominal pain during a routine follow-up visit. Laparotomy and ileocecectomy for a perforated ileal mass confirmed metastatic embryonal rhabdomyosarcoma with 1 out of 14 positive lymph node metastases. This case demonstrates that, although rare, intra-abdominal metastases should be considered when patients with a rhabdomyosarcoma present with abdominal complaints.

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.

Complete loss of TP53 and RB1 is associated with complex genome and low immune infiltrate in pleomorphic rhabdomyosarcoma

Rhabdomyosarcoma accounts for roughly 1% of adult sarcomas, with pleomorphic rhabdomyosarcoma (PRMS) as the most common subtype. Survival outcomes remain poor for patients with PRMS, and little is known about the molecular drivers of this disease. To better characterize PRMS, we performed a broad array of genomic and immunostaining analyses on 25 patient samples. In terms of gene expression and methylation, PRMS clustered more closely with other complex karyotype sarcomas than with pediatric alveolar and embryonal rhabdomyosarcoma. Immune infiltrate levels in PRMS were among the highest observed in multiple sarcoma types and contrasted with low levels in other rhabdomyosarcoma subtypes. Lower immune infiltrate was associated with complete loss of both TP53 and RB1. This comprehensive characterization of the genetic, epigenetic, and immune landscape of PRMS provides a roadmap for improved prognostications and therapeutic exploration.

The magnetic resonance characteristics of sinonasal rhabdomyosarcoma in adults: analysis of 27 cases and comparison with pathological subtypes

BACKGROUND

Sinonasal rhabdomyosarcoma (RMS) in adults is extremely rare, and early diagnosis and treatment are crucial to improve the patient's prognosis. The purpose of this study was to evaluate the magnetic resonance imaging (MRI) findings of sinonasal RMS in adults and analyze the correlations between the imaging features and pathological subtypes.

METHODS

We reviewed 27 patients with pathologically proven RMS of the nasal cavity and paranasal sinuses, including embryonal RMS (ERMS) in 14 patients, alveolar RMS (ARMS) in seven patients, and mixed-type RMS in six patients. Conventional MRI was performed in all 27 patients, and high-resolution diffusion-weighted imaging was conducted in 25 patients. The tumor location, size, morphological features, signal intensity, texture, contrast enhancement characteristics, lymph node metastases, apparent diffusion coefficients (ADCs), and involvement of local soft tissues were independently assessed by two authors.

RESULTS

On MR imaging, sinonasal RMS appeared isointense on T1-weighted imaging in 21 cases (77.8%) and heterogeneously hyperintense on T2-weighted imaging in 18 patients (66.7%). After enhancement, the tumors were heterogeneously enhanced in 24 cases (88.9%). Botryoid enhancement with multiple small rings resembling bunches of grapes was found in 15 cases (55.6%). Mucosal invasion of the maxillary sinus was identified in 51.9% patients. Skull and orbit involvement were found in 55.6% and 81.5% patients, respectively. Lymph node metastasis was seen in 18 cases (66.7%). There were significant differences in botryoid enhancement (P = 0.044) and skull involvement (P = 0.044) among different histological subtypes. The mean ADC value of RMS was 0.73 ± 0.082 × 10^-3 mm²/s, and there was no significant difference among different histological subtypes.

CONCLUSIONS

Some characteristic MRI findings such as botryoid enhancement in the ethmoid sinus, involvement of the orbit and skull, and a lower ADC value can provide important clues for preoperative diagnosis of sinonasal RMS in adults. Further, botryoid enhancement was more common in ERMS, while skull involvement was more common in ARMS.

Characterization of a rhabdomyosarcoma reveals a critical role for SMG7 in cancer cell viability and tumor growth

Soft-tissue sarcomas (STSs) are a rare and diverse group of mesenchymal cancers plagued with aggression, poor response to systemic therapy, and high rates of recurrence. Although STSs generally have low mutational burdens, the most commonly mutated genes are tumor suppressors, which frequently acquire mutations inducing nonsense-mediated mRNA decay (NMD). This suggests that STS cells may exploit NMD to suppress these anti-cancer genes. To examine the role that the NMD factor SMG7 plays in STS, we developed an inducible knockout mouse model in the Trp53-/- background. Here, we isolated a subcutaneous STS and identified it as a rhabdomyosarcoma (RMS). We report that knockout of SMG7 significantly inhibited NMD in our RMS cells, which led to the induction of NMD targets GADD45b and the tumor suppressor GAS5. The loss of NMD and upregulation of these anti-cancer genes were concomitant with the loss of RMS cell viability and inhibited tumor growth. Importantly, SMG7 was dispensable for homeostasis in our mouse embryonic fibroblasts and adult mice. Overall, our data show that the loss of SMG7 induces a strong anti-cancer effect both in vitro and in vivo. We present here the first evidence that disrupting SMG7 function may be tolerable and provide a therapeutic benefit for STS treatment.

Practical Management of Adult Ultra-Rare Primary Retroperitoneal Soft Tissue Sarcoma: A Focus on Perivascular Epithelioid Tumours and Extraosseous Ewing Sarcoma

With the exception of well-differentiated liposarcoma, dedifferentiated liposarcoma, leiomyosarcoma, solitary fibrous tumour, malignant peripheral nerve sheath tumour, and undifferentiated pleomorphic sarcoma, the majority of the ≈70 histologic subtypes of retroperitoneal sarcoma are defined as 'ultra-rare' sarcomas, with an incidence of ≤1-5/1,000,000 persons/year. For most of these ultra-rare RPS subtypes, diagnosis and treatment follows international guidelines for the management of more common RPS histologies, with en bloc surgical resection as the mainstay of curative treatment, and enrolment in clinical trials where possible. Because the treatment of RPS is heavily driven by histology, the surgeon must be familiar with specific issues related to the diagnosis and management of ultra-rare sarcoma subtypes. Expert radiological and surgeon reviews are required to differentiate similarly presenting tumours where surgery can be avoided (e.g., angiomyolipoma), or where upfront systemic therapy is indicated (e.g., extraosseous Ewing's sarcoma). Thus, the management of all retroperitoneal sarcomas should occur at a sarcoma referral centre, with a multidisciplinary team of experts dedicated to the surgical and medical management of these rare tumours. In this focused review, we highlight how diagnosis and management of the ultra-rare primary RPS histologies of malignant perivascular epithelioid cell tumour (PEComa), extraosseous Ewing sarcoma (EES), extraosseous osteosarcoma (EOS), and rhabdomyosarcoma (RMS) critically diverge from the management of more common RPS subtypes.

Germline genetic variants and pediatric rhabdomyosarcoma outcomes: a report from the Children's Oncology Group

BACKGROUND

Relative to other pediatric cancers, survival for rhabdomyosarcoma (RMS) has not improved in recent decades, suggesting the need to enhance risk stratification. Therefore, we conducted a genome-wide association study for event-free survival (EFS) and overall survival (OS) to identify genetic variants associated with outcomes in individuals with RMS.

METHODS

The study included 920 individuals with newly diagnosed RMS who were enrolled in Children's Oncology Group protocols. To assess the association of each single nucleotide polymorphism (SNP) with EFS and OS, we estimated hazard ratios (HRs) and 95% confidence intervals (CIs) using multivariable Cox proportional hazards models, adjusted for clinical covariates. All statistical tests were two sided. We also performed stratified analyses by histological subtype (alveolar and embryonal RMS) and carried out sensitivity analyses of statistically significant SNPs by PAX3/7-FOXO1 fusion status and genetic ancestry group.

RESULTS

We identified that rs17321084 was associated with worse EFS (HR = 2.01, 95% CI = 1.59 to 2.53, P = 5.39 × 10-9) and rs10094840 was associated with worse OS (HR = 1.84, 95% CI = 1.48 to 2.27, P = 2.13 × 10-8). Using publicly available data, we found that rs17321084 lies in a binding region for transcription factors GATA2 and GATA3, and rs10094840 is associated with SPAG1 and RNF19A expression. We also identified that CTNNA3 rs2135732 (HR = 3.75, 95% CI = 2.34 to 5.99, P = 3.54 × 10-8) and MED31 rs74504320 (HR = 3.21, 95% CI = 2.12 to 4.86, P = 3.60 × 10-8) were associated with worse OS among individuals with alveolar RMS.

CONCLUSIONS

We demonstrated that common germline variants are associated with EFS and OS among individuals with RMS. Additional replication and investigation of these SNP effects may further support their consideration in risk stratification protocols.

Embryonal Rhabdomyosarcoma of the Tongue in Adults

(1) Background: Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in the first two decades of life. One third of cases appear in the head and neck, with 60% of these being embryonal type. RMS is extremely rare in adults, comprising only 1% of adult malignancies, and of those, only 3.3% are rhabdomyosarcomas. (2) Case report: A 46 y.o. male presented with a 1 cm exophytic pediculated painless lesion on the dorsum of his tongue, with progressive growth for 3 months. An excisional biopsy revealed an "embryonal rhabdomyosarcoma with fusocellular areas, with negative rearrangement for gen FOXO1A, negative MDM2 (only focal positivity), and positive INI-1". Subsequent contrast-enhanced MRI concluded the presence of a lesion with imprecise margins in the right half-tongue, 15 × 8 × 7 mm (longitudinal × transverse × craniocaudal), compatible with a sarcoma. The patient underwent a partial centrolingual glossectomy followed by reconstruction with a buccinator muscle local flap. After surgery, he received chemotherapy with eight cycles of VAC (vincristine, actinomycin, and cyclophosphamide) protocol. The patient is now disease free after 42 months, with good tongue function. (3) Discussion and conclusions: Embryonal RMS is an extremely rare sarcoma in adults, and the location in the tongue is even more exceptional (only two more similar cases are reported in the literature). The prognosis in adults is significantly poorer than in children. A complete margin-free resection with an adequate chemotherapy protocol is the treatment of choice in cases such as these.