Treatment strategies and outcomes for spinal rhabdomyosarcoma: A series of 11 cases in a single center and review of the literature.

OBJECTIVES: Rhabdomyosarcoma (RMS) involving the spine is rare. The aim of the present study is to explore the clinicopathological features, surgical treatments and outcomes of this rare disease. PATIENTS AND METHODS: Eleven patients with spinal RMS who received surgery in our institution between 2012 and 2018 were retrospectively investigated. The literature on spinal RMS was also reviewed. RESULTS: Our study consisted of 7 cases of primary RMS and 4 cases of metastatic RMS. Seven primary and one metastatic spinal RMS received radical resection, the remaining three metastatic patients received palliative resection. Eight patients died with a median survival time of 8 months. The mean value of Ki-67 positivity was 48.2 %. Literature review revealed a total of 22 previously reported cases. 54.5 % of the pooled cases of the 33 patients were under the age of 18. Of the 20 patients with primary spinal RMS, 9 cases were diagnosed as embryonal, while 6 of the 13 metastatic patients were diagnosed as alveolar. Multiple modalities, including surgery and concurrent adjuvant therapy were performed in 19 patients. The median overall survival (OS) for 28 patients with detailed follow-up information was 10 months. Radical resection offered a significant longer median OS than non-radical resection (18 vs. 6 months, p = 0.027). CONCLUSION: Spinal RMS mainly affects young patients. The embryonal form and alveolar form is the most frequent subtype for primary and metastatic spinal RMS respectively. Spinal RMS is highly aggressive with dismal prognosis. Multimodality therapies are the mainstay of treatment. Radical resection is strongly recommended in eligible patients.

Regional Nodal Control for Head and Neck Alveolar Rhabdomyosarcoma.

PURPOSE: To assess clinical outcomes and patterns of failure, particularly regional nodal control, for pediatric patients treated with proton beam therapy (PBT) for head and neck alveolar rhabdomyosarcoma (HN-ARMS). MATERIALS AND METHODS: Between 2006 and 2015, 14 patients with HN-ARMS were enrolled in a prospective registry protocol and treated with PBT at a single institution. Of the patients, 8 (57%) presented with localized disease and 6 (43%) with regional nodal metastases. All patients were treated with systemic therapy per accepted cooperative group regimens. All patients received PBT to the primary site and involved nodal disease with a median dose of 50.4 Gy (relative biological effectiveness). Elective nodal irradiation was not delivered. RESULTS: The median follow-up period for surviving patients was 4.3 years. The 5-year overall survival and disease-free survival rates for the cohort (N = 14) were 45% and 25%, respectively. There were 10 relapses in the cohort: 7 regional nodal, 1 combination local and regional nodal, and 2 leptomeningeal. In 6 of 8 patients (75%) with no nodal disease at diagnosis, isolated regional nodal relapse developed. All nodal relapses occurred in first-echelon draining lymph node basins relative to the primary tumor site. Of 6 patients who presented with nodal metastases, 2 had regional nodal relapse; both of these nodal relapses occurred in the same nodal basin that was initially involved by disease but was not completely targeted as part of the primary treatment plan. CONCLUSIONS: High rates of regional nodal relapse are observed for HN-ARMS patients, including patients with no nodal disease at diagnosis. These data suggest that HN-ARMS patients may benefit from elective nodal irradiation to treat at-risk draining lymph node stations relative to the primary tumor site. We further recommend coverage of the entire nodal level for any sites of initial nodal disease at diagnosis, given the high risk of failure at these sites.

Primary alveolar rhabdomyosarcoma of the bone: two cases and review of the literature.

BACKGROUND: Rhabdomyosarcoma (RMS) is a malignant tumor of mesenchymal origin and comprises the largest category of soft-tissue sarcomas both in children and adolescents. From a pediatric oncology point of view, RMS has traditionally been classified into alveolar (ARMS) and embryonal (ERMS) subtypes. The anatomical localization of the tumor may vary, but commonly involve the head/neck regions, male and female urogenital tract or the trunk and extremities. CASE PRESENTATION: Here, we report two challenging cases involving 17- and 9-years-olds males where diffuse and multiplex bone lesions suggested either a hematological disease or a primary bone tumor (mesenchymal chondrosarcoma). Biopsies, proved a massive infiltration of the bone marrow cavity with rhabdomyosarcoma. In both cases, the ARMS subtype was confirmed using FOXO1 break-apart probes (FISH). Radiological examination could not identify primary soft tissue component in any localization at the time of diagnosis in either cases. CONCLUSIONS: Primary alveolar rhabdomyosarcoma of the bone as a subtype of ARMS, seems to be a distinct clinico-pathological entity with challenging diagnostic difficulties and different, yet better, biological behavior in comparison to soft tissue ARMS. However, it is difficult to be characterized or predict its prognosis and long-term survival as only sporadic cases (four) were reported so far.

Alveolar Rhabdomyosarcoma of the foot metastasizing to the Iris: report of a rare case.

BACKGROUND: Intraocular iris rhabdomyosarcoma is extremely rare, and in the 3 cases reported to date occurred as the primary site of tumour growth. We report a case of rhabdomyosarcoma of the foot metastasizing to the iris. CASE PRESENTATION: An 18-year-old white female was referred to the London Ocular Oncology Service for management of a metastatic rhabdomyosarcomatous deposit in the iris, a metastasis from alveolar rhabdomyosarcoma of the foot. She was diagnosed nearly 2 years earlier with the primary sarcoma with extensive systemic spread and treated by resection of the foot lesion and chemotherapy, and achieved a partial remission. The left iris deposit was noted while she was receiving systemic chemotherapy, heralding a relapse. However, anterior uveitis and raised intraocular pressure developed and she was referred to our service for further management. A left iris secondary rhabdomyosarcoma deposit was noticed and in addition a lacrimal gland mass, as indicated by ultrasound B scan of the eye and orbit. The patient was treated with external beam radiotherapy to the globe and orbit, but died 2 months after treatment completion. CONCLUSION: Rhabdomyosarcoma of the iris is very rare and was previously documented only as a primary malignancy in this location. We report that secondary spread to the iris can also occur, in this case as the first sign of widely disseminated systemic relapse.

Primary Renal Rhabdomyosarcoma: An Unusual Bone Metastasizing Tumor of Kidney.

Rhabdomyosarcoma (RMS) is one of the common malignant tumors in the pediatric age group. There is only a single case report of primary renal alveolar RMS. Fine needle aspiration (FNA) findings of primary renal RMS has not been reported so far. Hence we present an unusual case of primary alveolar RMS of the kidney. An 11 year old boy presented with an abdominal mass. On FNA a diagnosis of undifferentiated sarcoma and anaplastic Wilms tumor were considered. The tumor was resected and showed histopathological features of alveolar rhabdomyosarcoma. He developed multiple bony metastases and succumbed to the illness despite aggressive chemotherapy. RMS of the kidney should be considered in the differential diagnosis of children with a renal mass, and may have an aggressive clinical course with bone metastases.

Radiation therapy may increase metastatic potential in alveolar rhabdomyosarcoma.

BACKGROUND: We previously determined that radiation could be safely administered using a mouse-flank in vivo model to both alveolar (Rh30) and embryonal (Rh18) rhabdomyosarcoma xenografts. Mice from both tumor lines in this experiment developed metastases, an event not previously described with these models. We sought to determine if radiation-induced changes in gene expression underlie an increase in the metastatic behavior of these tumor models. PROCEDURE: Parental Rh18 and Rh30 xenografts, as well as tumor that recurred locally after radiotherapy (Rh18RT and Rh30RT), were grown subcutaneously in the flanks of SCID mice and then subjected to either fractionated radiotherapy or survival surgery alone. Metastasis formation was monitored and recorded. Gene expression profiling was also performed on RNA extracted from parental, recurrent, and metastatic tissue of both tumor lines. RESULTS: Rh30 and Rh30RT xenografts demonstrated metastases only if they were exposed to fractionated radiotherapy, whereas Rh18 and Rh18RT xenografts experienced significantly fewer metastatic events when treated with fractionated radiotherapy compared to survival surgery alone. Mean time to metastasis formation was 40 days in the recurrent tumors and 73 days in the parental xenografts. Gene expression profiling noted clustering of Rh30 recurrent and metastatic tissue that was independent of the parental Rh30 tissue. Rh18RT xenografts lost radiosensitivity compared to parental Rh18. CONCLUSION: Radiation therapy can significantly decrease the formation of metastases in radio-sensitive tumors (Rh18) and may induce a more pro-metastatic phenotype in radio-resistant lines (Rh30).

Alveolar rhabdomyosarcoma of nasopharynx and paranasal sinuses with metastasis to breast in a middle-aged woman: a case report and literature review.

Alveolar rhabdomyosarcoma (ARMS) is a common soft tissue tumor in children which can rarely metastasize to the breast in adults. Here we report the rare case of a 42-year-old Asian woman, who was diagnosed with ARMS of the nasopharynx and paranasal sinuses, and got a complete remission (CR) after surgery and chemoradiotherapy. Then the patient relapsed in the unilateral breast seventeen months later. Histology and immunohistochemistry of the primary sites and the breast lesions, combined with FISH, have been performed to confirm the diagnosis of metastatic alveolar rhabdomyosarcoma. With a rational therapeutic regimen of surgery, chemotherapy and radiotherapy, the patient has got a complete remission again.

Pituitary metastasis of rhabdomyosarcoma: a case report and review of the literature.

INTRODUCTION: The pituitary gland is an uncommon site for metastases, in particular from rhabdomyosarcoma. Some authors have reported a recent increase in the incidence of metastases at infrequent sites, such as brain or bone, probably due to the expanded treatment options and the resulting improved survival. Treatment options are limited, but must be discussed and adapted to the patient profile. CASE PRESENTATION: We report the case of a 17-year-old Arabic man, diagnosed with alveolar rhabdomyosarcoma of the left shoulder, who, after several cycles of chemotherapy, presented symptoms and signs of pituitary dysfunction. To the best of our knowledge, it is the first case described. CONCLUSIONS: Pituitary metastasis of rhabdomyosarcoma is a rare situation, which must be actively researched to have access to an optimal therapeutic approach.

Adult rhabdomyosarcoma of the maxillary sinus with orbital extension.

A 40-year-old male presented with 2 weeks of left facial pain, nasal congestion, dysphonia, and epistaxis along with left-sided epiphora. CT showed a large infiltrative mass centered in the left maxillary sinus with extension into the left orbit, bilateral paranasal sinuses, nasal cavity, and bilateral enlarged cervical lymph nodes. Biopsy results confirmed adult alveolar rhabdomyosarcoma (RMS). Systemic workup confirmed bilateral cervical lymph node metastasis. Currently the patient is undergoing chemotherapy. We describe a rare case of adult paranasal sinus RMS with orbital invasion.

Using a rhabdomyosarcoma patient-derived xenograft to examine precision medicine approaches and model acquired resistance.

BACKGROUND: Precision (Personalized) medicine has the potential to revolutionize patient health care especially for many cancers where the fundamental disease etiology remains either elusive or has no available therapy. Here we outline a study in alveolar rhabdomyosarcoma, in which we use gene expression profiling and a series of drug prediction algorithms combined with a matched patient-derived xenograft (PDX) model to test bioinformatically predicted therapies. PROCEDURE: A PDX model was developed from a patient biopsy and a number of drugs identified using gene expression analysis in combination with drug prediction algorithms. Drugs chosen from each of the predictive methodologies, along with the patient's standard-of-care therapy (ICE-T), were tested in vivo in the PDX tumor. A second study was initiated using the tumors that re-grew following the ICE-T treatment. Further expression analysis identified additional therapies with potential anti-tumor efficacy. RESULTS: A number of the predicted therapies were found to be active against the tumors in particular BGJ398 (FGFR2) and ICE-T. Re-transplanted ICE-T treated tumorgrafts demonstrated a decreased response to ICE-T recapitulating the patient's refractory disease. Gene expression profiling of the ICE-T treated tumorgrafts identified cytarabine (SLC29A1) as a potential therapy, which was shown, along with BGJ398, to be highly active in vivo. CONCLUSIONS: This study illustrates that PDX models are suitable surrogates for testing potential therapeutic strategies based on gene expression analysis, modeling clinical drug resistance and hold the potential to assist in guiding prospective patient care.

Cytologic diagnosis of metastatic alveolar rhabdomyosarcoma to the thyroid gland by fine-needle aspiration.

BACKGROUND: Metastases to the thyroid gland, although rare, are important entities to consider when evaluating malignant cells on a thyroid fine-needle aspiration (TFNA) specimen. Cellular TFNA specimens with small round blue cells should prompt a broad differential: florid lymphocytic thyroiditis, lymphoma, metastases, as well as primary thyroid malignancies with similar morphologies such as poorly differentiated (insular) and medullary carcinomas. Age, clinical presentation and prior history must be considered in every case. CASE REPORT: We report, to the best of our knowledge, the first case of metastatic alveolar rhabdomyosarcoma (ARMS) to the thyroid gland, definitively diagnosed by TFNA. A 21-year-old female patient presented with a large mass in the right lobe of the thyroid. Her past history was significant for ARMS diagnosed 24 months earlier, currently in remission after successfully completing 40 weeks of chemoradiation therapy. The diagnosis of metastatic ARMS in the TFNA prompted a more thorough examination revealing previously unknown additional sites of metastases. CONCLUSION: Metastases to the thyroid gland are uncommon but should be considered in cases where atypical morphology is encountered. Small round blue cell tumors can metastasize to the thyroid gland, and clinical presentation, morphology, immunohistochemistry and molecular studies are helpful in differentiating between them.

Structural and functional studies of FKHR-PAX3, a reciprocal fusion gene of the t(2;13) chromosomal translocation in alveolar rhabdomyosarcoma.

Alveolar rhabdomyosarcoma (ARMS) is an aggressive pediatric cancer of skeletal muscle. More than 70% of ARMS tumors carry balanced t(2;13) chromosomal translocation that leads to the production of two novel fusion genes, PAX3-FKHR and FKHR-PAX3. While the PAX3-FKHR gene has been intensely studied, the reciprocal FKHR-PAX3 gene has rarely been described. We report here the cloning and functional characterization of the FKHR-PAX3 gene as the first step towards a better understanding of its potential impact on ARMS biology. From RH30 ARMS cells, we detected and isolated three versions of FKHR-PAX3 cDNAs whose C-terminal sequences corresponded to PAX3c, PAX3d, and PAX3e isoforms. Unlike the nuclear-specific localization of PAX3-FKHR, the reciprocal FKHR-PAX3 proteins stayed predominantly in the cytoplasm. FKHR-PAX3 potently inhibited myogenesis in both non-transformed myoblast cells and ARMS cells. We showed that FKHR-PAX3 was not a classic oncogene but could act as a facilitator in oncogenic pathways by stabilizing PAX3-FKHR expression, enhancing cell proliferation, clonogenicity, anchorage-independent growth, and matrix adhesion in vitro, and accelerating the onset of tumor formation in xenograft mouse model in vivo. In addition to these pro-oncogenic behaviors, FKHR-PAX3 also negatively affected cell migration and invasion in vitro and lung metastasis in vivo. Taken together, these functional characteristics suggested that FKHR-PAX3 might have a critical role in the early stage of ARMS development.

The impact of age on outcome of embryonal and alveolar rhabdomyosarcoma patients. A multicenter study.

BACKGROUND: The prognosis of rhabdomyosarcoma (RMS) in children and adolescents has improved since the introduction of multi-agent chemotherapy. However, outcome data of adults with RMS are scarce. This multicenter retrospective study investigated the effect of age on outcome of RMS. PATIENTS AND METHODS: Data were collected from three Dutch University Medical Centers between 1977-2009. The effect of age and clinical prognostic factors on relapse-free and disease-specific survival (DSS) were analyzed. RESULTS: Age as a continuous variable predicted poor survival in multivariate analysis. Five-year DSS was highest for non-metastatic embryonal RMS, followed by non-metastatic alveolar RMS and was poor in metastatic disease. Higher age correlated with unfavorable histological subtype (alveolar RMS) and with metastatic disease at presentation in embryonal RMS. In non-metastatic embryonal RMS and in all alveolar RMS, higher age was an adverse prognostic factor of outcome. CONCLUSION: This study indicates that age is a negative predictor of survival in patients with embryonal and alveolar RMS.

Alveolar rhabdomyosarcoma with multiple distal metastases. A case report and review of literature.

An 18-year-old boy, presented with a history of right hip pain with movement restriction and proptosis of right eye. There was severe anaemia, febrile neutropaenia and bleeding manifestations. CT scan of right orbit documented a retro orbital mass. MRI revealed a mass on right side of the pelvis with metastatic deposits in spine. Biopsy from that mass revealed alveolar rhabdomyosarcoma. Bone marrow biopsy showed sarcomatous involvement with decrease in all three cell lineages. Chemotherapy was started according to standard protocol. We lost the patient after 3 weeks of initiation of chemotherapy. In our case, the unusual primary site and presentation with multiple distal metastases makes this case stand apart and therefore worth reporting.

Differential expression of miRNAs in rhabdomyosarcoma and malignant rhabdoid tumor.

Alveolar rhabdomyosarcoma (RMA) and malignant rhabdoid tumor (MRT) have a frequent metastatic spread and a poor prognosis. Aberrant miRNA expression is often found in metastatic tumors. The aim of this study was to identify specific miRNA expression patterns in these tumors. We analyzed the expression of miRNAs in RMA and MRT in tissue samples and in the rhabdomyosarcoma (RMS) cell lines (Rh30 and RD). Selected target miRNAs were modulated with mimic or inhibitor oligonucleotides. Functional analysis was monitored by flow cytometry and migration assays. A set of 107 differentially expressed miRNAs showed tissue-specific clustering of RMA and MRT. Comparison with the Sarcoma microRNA Expression Database revealed RMA- and MRT-specific miRNAs. Metastatic invasion associated miRNA miR-9 was overexpressed in RMA. miR-200c-inhibiting migration-was lower expressed in RMA than in MRT. Transient transfection of RMS cells with a miR-200c mimic and miR-9( inhibitor did neither increase the expression of the known target E-cadherin nor decrease migration. Expression of E-cadherin could be induced in RD cells using decitabine, but demethylation did not influence cell migration. Despite a comparable high rate of metastatic invasion pediatric RMA and MRT show a different pattern of miRNA expression possibly allowing risk stratification.

RasGRF1 regulates proliferation and metastatic behavior of human alveolar rhabdomyosarcomas.

The involvement of the Ras superfamily of GTPases in the pathogenesis of rhabdomysarcoma (RMS) is not well understood. While mutant H-Ras leads to embryonal RMS (ERMS) formation in experimental animals and in Costello syndrome patients, no data exists on the potential role of Ras GTPases in the pathogenesis of alveolar RMS (ARMS). To address this issue better, we focused on the role of the GTP exchange factor RasGRF1 in this process. We observed that, in comparison to normal skeletal muscle cells, RasGRF1 mRNA is upregulated in the majority of human ARMS cell lines and subsequently confirmed its high expression in patient samples. By employing confocal microscopy analysis, we observed RasGRF1 accumulation in cell filopodia, which suggests its involvement in ARMS cell migration. Furthermore, we observed that RasGRF1 becomes phosphorylated in ARMS after stimulation by several pro-metastatic factors, such as SDF-1 and HGF/SF, as well as after exposure to growth-promoting Igf-2 and insulin. More importantly, activation of RasGRF1 expression correlated with activation of p42/44 MAPK and AKT. When the expression of RasGRF1 was down-regulated in ARMS cells by an shRNA strategy, these RasGRF1-kd RMS cells did not respond to stimulation by SDF-1, HGF/SF, Igf-2 or insulin by phosphorylation of p42/44 MAPK and AKT and lost their chemotactic responsiveness; however, their adhesion was not affected. We also observed that RasGRF1-kd ARMS cells proliferated at a very low rate in vitro, and, more importantly, after inoculation into immunodeficient SCID/beige inbred mice they formed significantly smaller tumors. We conclude that RasGRF1 plays an important role in ARMS pathogenesis and is a new potential therapeutic target to inhibit ARMS growth.

The over-expression of cell migratory genes in alveolar rhabdomyosarcoma could contribute to metastatic spread.

Alveolar (ARMS) and Embryonal (ERMS) rhabdomyosarcoma differ in their response to current treatments. The ARMS subtype has a less favourable prognosis and often presents with widespread metastases, while the less metastatic ERMS has a 5 year survival rate of more than 80 %. In this study we investigate gene expression differences that could contribute to the high frequency of metastasis in ARMS. Microarray analysis identified significant differences in DNA repair, cell cycle and cell migration between the two RMS subtypes. Two genes up regulated in ARMS and involved in cell migration; the engulfment and cell motility gene 1 (ELMO1) and NEL-like 1 gene (NELL1) were selected for further investigation. Over-expression of ELMO1 significantly increased cell invasion from 24.70 ± 7% to 93 ± 5.4% in primary myoblasts and from 29.43 ± 2.1% to 87.33 ± 4.1% in the ERMS cell line RD. siRNA knockout of ELMO1 in the ARMS cell line RH30 significantly reduced cell invasion from 88.2 ± 3.8% to 35.2 ± 2.5%. Over-expression of NELL1 significantly increased myoblast invasion from 23.6 ± 6.9% to 100 ± 0.1%, but had no effect on invasion of the ERMS cell line RD. These findings suggest that ELMO1 may play a key role in ARMS metastasis. NELL1 increased invasion in primary myoblasts, but other factors required for it to enhance motility were not present in the RD ERMS cell line. Impairing ELMO1 function by pharmacological or siRNA knockdown could be a highly effective approach to reduce the metastatic spread of RMS.