An Evaluation of Risk Factors for Intracranial Metastases of Sarcomas: A Systematic Review and Meta-Analysis

INTRODUCTION

Sarcomas, a group of neoplasms comprising both tissue and bone soft tissue tumors, has an increasing prevalence in recent years. Prognosis significantly hinges on early detection, and if not detected early, may consequently metastasize. This review will be the first systematic review and meta-analysis characterizing the presentation and progression of brain metastases from bone and soft tissue cancers.

METHODS

The PubMed, Scopus, and Web of Science databases were queried to identify studies reporting the incidence of intracranial brain metastases from primary sarcoma to the present. Abstract and full-text screening of 1822 initial articles returned by preliminary search yielded 28 studies for inclusion and data extraction. Qualitative assessment of the studies was conducted in accordance with the Newcastle-Ottawa Scale criteria. Meta-analyses were applied to assess risk factors on outcomes.

RESULTS

The average age within the cohort was 27.9 years with a male and female prevalence of 59.1% and 40.9%, respectively. The odds ratio for living status (dead/alive) was calculated for several risk factors - male/female [OR 1.14, 95% CI 0.62, 2.07], single/multiple metastases [OR 0.67, 95% CI 0.35, 1.28], lung metastases/not [OR 1.63, 95% CI 0.85, 3.13], surgery/no surgery [OR 0.49, 95% CI 0.20, 1.21]. The standardized mean differences for duration from diagnoses to metastases were likewise analyzed - male/female [SMD 0.13, 95% CI -0.15, 0.42], single/multiple metastases [SMD 0.11, 95% CI -0.20, 0.42], lung metastases/not [SMD -0.03, 95% CI -0.38, 0.32], surgery/no surgery [SMD 0.45, 95% CI -0.18, 1.09]. The standardized mean differences for duration from metastases to death were analyzed - lung metastases/not [SMD 0.43, 95% CI -0.08, 0.95].

CONCLUSIONS

Our study observed no statistically significant differences in mortality rate among several patient risk factors. Consequentially, there lacks a clear answer as to whether or not an association between mortality rates exists with these patient factors. As such, it is important to continue research in brain-metastasizing sarcomas despite their relative rarity.

Survival outcomes of patients with brain metastasis of osteosarcoma can be improved by aggressive multi-disciplinary interventions including chemotherapy

BACKGROUND/OBJECTIVE

Brain metastasis in osteosarcoma (BMO) is rare and its clinical characteristics are often buried among studies on brain metastasis of bone and soft tissue sarcomas. The aim of the present study was to summarize the incidence, clinical characteristics, treatment and outcomes of patients with BMO.

METHODS

This retrospective study included 7 patients with BMO who received treatment in our center between 2005 and 2019. The clinical medical records of the 7 patients, together with data of 70 BMO patients published in 33 articles and retrieved by means of PubMed and Medline, were analyzed, retrospectively.

RESULTS

Data analysis of the 97 BMO patients showed a high correlation between the interval from the primary diagnosis to BMO occurrence and the interval from the primary diagnosis to prior metastases. Multivariate analysis showed that chemotherapy, radiotherapy and surgery were three main factors affecting the overall survival of BMO patients (HR = 0.427; HR = 0.372; HR = 0.296). Surgery combined with chemotherapy or radiotherapy offered a better overall survival than surgery alone.

CONCLUSION

Patients with BMO may obtain survival benefits from regular neuroimaging and early aggressive multi-disciplinary interventions including surgical resection, postoperative radiotherapy and chemotherapy.

SYNOPSIS

This is a retrospective study describing the characteristics of metastasic intervals, locations, clinical features and prognosis in 97 patients with brain metastasis of osteosarcoma (BMO). Multivariate analysis showed that chemotherapy was effective as surgery and radiotherapy for the treatment of BMO. Our findings emphasize the importance of regular neuroimaging and early aggressive multi-disciplinary interventions including surgical resection, postoperative radiotherapy and chemotherapy.

Characterization of pediatric non-hematopoietic tumor metastases to the central nervous system: A single institution review

Central nervous system (CNS) metastases represent a small portion of pediatric CNS neoplasms and data surrounding this condition with high morbidity is scarce. Single institutional archival institutional pathology records between 1999 and 2022 were searched for patients over 21 years old and younger with CNS, dura, cranial nerve, CSF, or leptomeningeal metastases; 41 cases were identified. We documented primary tumor types and locations, metastasis locations, types of invasion (direct extension vs distant metastasis), times from imaging or pathologic diagnosis to CNS involvement, and outcomes. Distant metastasis was the most common mechanism of metastasis (n = 32, 78%). Interval times to CNS metastasis varied by both tumor type and primary tumor location. In this cohort, osteosarcoma portended the shortest survival following CNS metastasis. This study highlights the diverse mechanisms and locations of CNS involvement in pediatric CNS metastases and illuminates a need for varied monitoring strategies when considering primary tumor type and anatomic location.

Brain metastases of sarcoma: a rare phenomenon in rare tumours

The usual site for distant metastases of sarcoma is lungs, while brain metastasis (BM) occurs much less frequently and usually late in the disease progression. Despite the advancement in cancer treatment, the outcome for patients with brain metastasis is poor, and their lifespan is short. The frequency of BM in sarcoma seems to be affected by the location and histology of the primary tumour. Sarcoma subtypes with a high propensity for brain metastasis are ASPS, leiomyosarcoma and osteosarcoma. There are no clear guidelines for the treatment of sarcoma brain metastasis. However, therapeutic options include surgery, radiotherapy and chemotherapy, and are often combined. Targeted therapies are a promising treatment option for sarcoma but require investigation in patients with BM. The following review presents the data on sarcoma brain metastasis incidence, treatment and prognosis.

Primary Intracranial Alveolar Soft Part Sarcoma: A Report of 3 Cases

Alveolar soft part sarcoma (ASPS) commonly involves extremities and head and neck regions. Primary intracranial ASPS is rare. We report a series of 3 primary intracranial ASPS. These were not suspected clinically and histopathology with immunohistochemistry proved to be diagnostic in all 3 tumors.

Intracranial Metastasis of Extracranial Chondrosarcoma: Systematic Review With Illustrative Case

BACKGROUND

Cerebral chondrosarcoma metastases are rare and aggressive neoplasms. The rarity of presentation has precluded rigorous analysis of diagnosis, risk factors, treatment, and survival. We analyzed every reported case through exhaustive literature review. We further present the first case with Maffucci syndrome.

METHODS

Three databases, PubMed, Embase, and Google Scholar, and crossed references were queried for cerebral chondrosarcoma metastases. Extracted variables included demographics, risk factors, tumor characteristics, interventions, and outcomes. Univariate and multivariate analyses were performed.

RESULTS

Fifty-six patients were included from 1,489 literature results. The average age at brain metastasis was 46.6±17.6 years and occurred at a median of 24±2.8 months from primary diagnosis. Primary tumor histology (dedifferentiated 5.0±1.5 months, mesenchymal 24±3.0 months, conventional 41±7.4 months, p<0.05) and grade (low grade 54±16.7 months vs. high-grade 10±6.4 months, p<0.001) correlated with time interval until brain metastasis. A multiple enchondromatosis syndrome occurred in 13.2% of cases. At time of brain metastases diagnosis, extracranial metastases were identified in 76.2% of cases. Median survival after the development of brain metastasis was 2.0±0.78 months with a 1-year survival of 10.0%. On regression analysis, surgery reduced brain metastasis mortality risk and radiation trended towards reduced mortality risk (surgery: hazard ratio [HR] 0.22, 95% confidence interval [CI] 0.064-0.763, p=0.017; radiation: HR 0.31, 95% CI 0.091-1.072, p=0.064).

CONCLUSION

We present a systematic review of cerebral chondrosarcoma metastases. Primary tumor histology and grade correlate with time until cerebral metastasis. Following cerebral metastasis, these tumors have poor prognosis and modestly benefit from surgery.

A retrospective analysis of the prognosis of Japanese patients with sarcoma brain metastasis

BACKGROUND

Bone and soft tissue sarcomas are rare tumors and extremely rarely metastasize to the brain. Previous studies have examined the characteristics and poor prognostic factors in cases of sarcoma brain metastasis (BM). Due to the rarity of cases of BM from sarcoma, limited data exist concerning the prognostic factors and treatment strategies.

METHODS

A retrospective single-center study was performed on sarcoma patients with BM. The clinicopathological characteristics and treatment options for BM of sarcoma were investigated to identify predictive prognostic factors.

RESULTS

Between 2006 and 2021, 32 patients treated for newly diagnosed BM at our hospital were retrieved among 3133 bone and soft tissue sarcoma patients via our database. The most common symptom was headache (34%), and the most common histological subtypes were alveolar soft part sarcoma (ASPS) and undifferentiated pleomorphic sarcoma (25%). Non-ASPS (p = 0.022), presence of lung metastasis (p = 0.046), a short duration between initial metastasis, and the diagnosis of brain metastasis (p = 0.020), and the absence of stereotactic radiosurgery for BM (p = 0.0094) were significantly correlated with a poor prognosis.

CONCLUSIONS

In conclusion, the prognosis of patients with brain metastases of sarcomas is still dismal, but it is necessary to be aware of the factors associated with a relatively favorable prognosis and to select treatment options appropriately.

Sacral Ewing sarcoma with rib, lung, and multifocal skull metastases: A rare case report and review of treatments

Ewing sarcoma (ES) rarely derives from the sacrum or mobile spine. The discovery of primary ES with multimetastatic involvements is exceedingly less frequent in clinical practice. A 23-year-old man with initial primary sacral ES developed metastases of rib, lung, and multifocal skull after receiving surgical intervention and series of adjuvant therapies. We provide this very rare case consisting of its clinical features, imaging findings, treatments, and outcomes. Therapeutic modalities of ES are also reviewed in previous published articles. The prognosis of metastatic ES remains dismal; effective therapeutic modalities for ES require multidisciplinary collaboration, with more high-quality clinical trials to promote the optimal protocols.

Brain Metastases from Adult Sarcomas: A Retrospective Cohort Study from the Hellenic Group of Sarcomas and Rare Cancers (HGSRC)

Brain metastases are rare events in patients with sarcoma and the available information is relatively limited. We retrospectively reviewed medical records of patients with sarcoma who developed brain metastases between April 2010 and April 2020 in six centers. Thirty-four adult patients were included with a median age at brain metastases diagnosis of 55.5 years (range, 18–75). The primary sarcomas originated either from soft tissue (n = 27) or bone (n = 7) and the most common subtypes were leiomyosarcoma (n = 8), Ewing sarcoma/peripheral neuroectodermal tumor (PNET) (n = 7) and osteosarcoma (n = 3). Most primary tumors were of high grade and located mainly in the extremities (n = 18). The vast majority of patients at the time of brain metastasis diagnosis already had extracranial metastatic disease (n = 26). The median time from sarcoma diagnosis to cerebral metastasis diagnosis was 16 months (range, 1–136). Treatment modalities for brain metastatic disease included whole-brain radiation therapy (WBRT) (n = 22), chemotherapy (n = 17), exclusive palliative care (n = 5), surgery (n = 9), targeted therapy (n = 6) or stereotactic radiosurgery (n = 2). Most patients experienced a progression of brain metastases (n = 11). The median overall survival from brain metastasis diagnosis was 3 months (range, 0–80). OS was significantly influenced by time-to-brain metastases (p = 0.041), WBRT (p = 0.018), surgery (p = 0.002) and chemotherapy (p = 0.006). In a multivariate analysis, only the localization of the primary (p = 0.047) and WBRT (p = 0.038) were associated with survival with statistical significance. Patients with sarcoma brain metastases have a particularly poor prognosis and an appropriate therapeutic approach is yet to be defined.

Brain Metastases in Patients With Soft-Tissue Sarcomas: Management and Survival-A SEER Population-Based Cohort Study

Brain metastases (BM) in soft-tissue sarcomas (STS) is associated with poor prognosis. This large population analysis presents (1) demographic and clinical variables of these patients, (2) potential risk factors, (3) impact of BM on overall survival, and (4) treatment strategies.

Surgical outcome and graded prognostic assessment of patients with brain metastasis from adult sarcoma: multi-institutional retrospective study in Japan

BACKGROUND

Brain metastasis (BM) is an uncommon complication of sarcomas with a poor prognosis. Little information is available about the feasibility and prognostic factors of surgical resection of BM from sarcomas.

METHODS

This study involved a retrospective analysis of 22 patients with BM from sarcomas who underwent resection at six institutes in Japan. Prognostic factors were analyzed to develop a graded prognostic assessment (GPA) using the log-rank test and Cox regression analysis. For validation of this GPA, we collected data on 100 surgical cases from 48 published reports.

RESULTS

Postoperative Karnofsky Performance Status (KPS) improved in 50% of our patients. Median overall survival (OS) was 21 months. Multivariate analysis showed age and alveolar soft part sarcoma (ASPS) were significant preoperative prognostic factors (P < 0.05). RTOG-RPA classification had no significant prognostic value. We developed a GPA system for OS after resection of BM. A score of 0 was assigned to patients aged 18-29 years with non-ASPS, 2 to patients aged 18-29 years with ASPS or 30-76 years with non-ASPS, and 4 to patients aged 30-76 years with ASPS. Median OS for patients with GPA scores of 0, 2, and 4 were 6.5, 16.0, and 44.0 months, respectively (P = 0.002). The results were validated by the data of 100 cases compiled (P < 0.001).

CONCLUSION

Median OS of patients with BM from sarcomas was comparable to that from carcinomas after resection. A new sarcoma-specific GPA may help patients and clinicians to select resection as an option for treatment of BM from sarcomas.

Brain metastases from Truncal and extremity bone and soft tissue sarcoma: Single institution study of oncologic outcomes

Brain metastases are a rare occurrence in patients with sarcoma. The prognosis for patients is poor, and treatment can contribute to considerable morbidity. We sought to examine the experience of our institution in managing these patients over a period of 17 years. We performed a retrospective cohort study of patients managed for sarcoma of the extremity or trunk who developed brain metastases from 2000 to 2017. Clinical data were analyzed and we assessed survival outcomes. 14 patients presenting at a mean age of 46.7 years were included. All patients were treated with radiotherapy for their brain metastases. 3 patients underwent surgical excision of their intracranial metastases. Two patients were treated with radium-223 dichloride. Kaplan–Meier survival analysis and the log rank test were used to calculate the survival probability, and to compare patient subgroups. All patients in this study developed lung or bone metastases at a mean interval of 13.3 months prior to the development of brain metastasis. The median interval from diagnosis of a brain metastasis to death was 3.6 months. The Kaplan–Meier survival probability at 6 months was 28.6%, and 14.3% at 1 year. Surgery was not found to be associated with increased survival. Patients with cerebellar metastasis had increased survival probability as compared to those with cerebral metastasis. Patients with extremity or trunk sarcoma who develop brain metastases frequently develop lung or bone metastases in the year preceding their diagnosis of brain metastasis. Patients with cerebellar metastasis may have better survival than those with cerebral metastasis, and an aggressive treatment approach should be considered. Despite aggressive treatment, the prognosis is grim.

Outcomes and the Role of Primary Histology Following LINAC-based Stereotactic Radiation for Sarcoma Brain Metastases

OBJECTIVES

The brain is a rare site for sarcoma metastases. Sarcoma's radioresistance also makes standard whole-brain radiotherapy less appealing. We hypothesize that stereotactic radiation techniques (stereotactic radiosurgery [SRS]/stereotactic fractionated radiotherapy [FSRT]) may provide effective local control.

MATERIALS AND METHODS

This single-institution retrospective analysis evaluated our experience with linear acceleator-based SRS/FSRT for sarcoma brain metastases. Time to event analysis was estimated via Kaplan-Meier. Univariable/multivariable Cox regression analyses followed to assess the impact of patient and disease characteristics on outcomes.

RESULTS

Between 2003 and 2018, 24 patients were treated with 34 courses of SRS/FSRT to 58 discrete lesions. The median age at first treatment was 57 years (range: 25 to 87 y). Majority of patients had concurrent lung metastases (n=21; 88%), diagnosed spindle cell sarcoma (n=15; 25%) or leiomyosarcoma (n=12; 21%) histology, and were treated with either SRS (n=43; median dose=19 Gy, range: 15 to 24 Gy) or FSRT (n=17; 3/5 fractions, median dose=25 Gy, range: 25 to 35 Gy). With a median follow-up after brain metastasis of 7.3 months, the 6 month/12 month local control, distant brain control, and overall survival of 89%/89%, 59%/34%, and 50%/38%, respectively. All local failures were of primary spindle cell histology (P<0.001), which was associated with poorer distant control (hazard ratio=25.8, 95% confidence interval: 3.1-536.4; P=0.003) on univariable analysis, and OS (hazard ratio=7.1, 95% confidence interval: 2.0-26.1; P=0.003) on multivariable analysis.

CONCLUSIONS

This is the largest patient cohort with sarcoma brain metastases treated with SRS/FSRT, it provides durable local control, despite a reputation for radioresistance. Further prospective evidence is required to determine the impact of primary histology on control and survival following brain metastasis diagnosis.

Cerebral metastasis from osteosarcoma: “Bone” in the brain

Although brain metastases from bone and soft tissue sarcoma are uncommon, advances in sarcoma treatment have led to an increasing incidence of them. We present a 23-year-old male with a history of metastatic femoral osteosarcoma, who presented with headache and unsteady gait and was diagnosed with a cerebellar metastasis. CT scan revealed a mass in the left cerebellar parenchyma with large intralesional central calcification and perilesional edema. Corticosteroid treatment led to neurological symptoms resolution, with a rapid tapering. The patient had also lung metastases and we opted to administer systemic treatment with the tyrosine kinase inhibitor cabozantinib. Given the relative radioresistance of osteosarcomas, the patient did not receive radiation therapy.

Primary Cardiac Sarcoma: A Rare, Aggressive Malignancy with a High Propensity for Brain Metastases

Introduction

Primary cardiac sarcoma (PCS) has a poor prognosis compared to other sarcomas due to late presentation, challenging resection, incidence of metastases, and limited efficacy of systemic therapies.

Methods

A medical record search engine was queried to identify patients diagnosed with PCS from 1992 to 2017 at the University of Michigan.

Results

Thirty-nine patients with PCS had a median age of 41 years (range 2–77). Common histologies were angiosarcoma (AS, 14), high-grade undifferentiated pleomorphic sarcoma (UPS, 10), and leiomyosarcoma (LMS, 5). Sites of origin were left atrium (18), right atrium (16), and pericardium (5). AS was the most common right-sided tumor; UPS was more common on the left. Eighteen patients presented with metastases involving lung (10), bone (7), liver (5), and brain (4). Twenty-five patients underwent resection, achieving 3 R₀ resections. Patients received a median of 2 (1–6) systemic therapies. Median overall survival (OS) was 12.1 months (range 0–79). Median OS was 14.0 months and 8.2 months in patients who did or did not undergo resection, respectively (p=0.018). Brain metastases occurred in 12 (31%) patients, 9 (75%) of whom had left heart tumors, at a median of 8.5 months (range 0–75) from diagnosis. Median OS was 5.6 months (range 0–30) after the diagnosis of brain metastases.

Conclusions

PCS portends a poor prognosis, because of difficulty in obtaining complete resection of sarcoma, advanced stage at diagnosis, and high risk of brain metastases. Providers should be aware of the increased risk of brain metastases and consider brain imaging at diagnosis and follow-up.

Brain Metastases from Adult Sarcoma: Prognostic Factors and Impact of Treatment. A Retrospective Analysis from the French Sarcoma Group (GSF/GETO)

BACKGROUND

Brain metastases (BM) from adult soft tissue or bone sarcomas are rare, and sparse data exist on their prognostic factors and management.

SUBJECTS, MATERIALS AND METHODS

A retrospective study was conducted in 15 centers of the French Sarcoma Group, plus one Canadian and one Swiss center, to report on clinical, histological, and treatment characteristics and to identify predictive factors of outcome.

RESULTS

Between 1992 and 2012, 246 patients with a median age of 50 years (range: 16-86) were managed for BM. BM included 221 cerebral and cerebellar metastases and 40 cases of meningeal sarcomatosis. The most frequent histopathological subtype was leiomyosarcoma (18.7%). Histological grade was high in 118 (48%) cases. Surgery of BM was carried out for 38 (15.5%) patients. Radiotherapy and chemotherapy were administered in 168 (68.3%) and 91 (37.0%) patients, respectively. Irrespective of treatment modality, BM were controlled in 113 patients (45.9%), including 31 partial responses (12.6%) and 18 complete responses (7.3%). The median overall survival from diagnosis of brain metastasis was 2.7 months (range: 0-133). In the multivariate analysis, the following parameters influenced overall survival: chemotherapy (hazard ratio [HR] = 0.38; 95% confidence interval [CI]: 0.26-0.48), surgery (HR = 0.40; 95% CI: 0.22-0.72), stereotactic radiotherapy (HR = 0.41; 95% CI: 0.19-0.90), whole-brain radiotherapy (HR = 0.51; 95% CI: 0.35-0.76), and grade (HR = 0.65; 95% CI: 0.43-0.98).

CONCLUSION

BM of sarcomas are rare and associated with a dismal outcome. Multidisciplinary management with chemotherapy, radiation therapy, and surgery is associated with a better survival.

IMPLICATIONS FOR PRACTICE

The incidence of brain and meningeal metastasis in bone and soft tissue sarcomas is estimated between 1% and 8%. Published data are derived from small retrospective case series, often in the pediatric population. A prognostic index is important to guide both clinical decision-making and outcomes research, but one such is lacking for adult sarcoma patients with brain metastases. The current study describes brain metastasis in a large cohort of sarcoma patients. This study, conducted within the French Sarcoma Group, describes the natural history of sarcoma brain metastasis and enables the proposal of strategic recommendations for subsequent clinical trials and for the management of such patients.

Sarcoma Brain Metastases: 28 Years of Experience at a Single Institution

BACKGROUND

Brain metastasis from sarcoma is rare, thus limited information is available. We examined sarcoma brain metastases diagnosed at our institution over a period of 28 years.

METHODS

This is a retrospective study of 112 cases. Clinical records were reviewed and clinical, pathological, and survival data were tabulated.

RESULTS

Undifferentiated sarcoma was the most common source. In 50 % of cases, the primary sarcoma was in the extremities. Most patients were adults at the time of first brain metastasis, and median age was 34.8 years. Although most patients evidenced metastatic disease to other sites prior to developing brain metastasis, in almost one quarter, brain was the initial site. Most of the metastatic foci were parenchymal, nonhemorrhagic, and solitary. Forty percent of the brain metastatic deposits were located in the frontal lobes. Thirty-one percent recurred-all within 5.3 years. Seventy-six percent of patients succumbed to the disease, with a median survival time of only 0.6 years. Hemorrhagic metastatic foci were found to be associated with significantly lower recurrence-free, as well as disease-specific survivals. No difference in survival was noted between single versus multiple deposits or primary soft tissue versus bone sarcomas. No statistically significant effect on survival was found when neurosurgical resection was combined with radiotherapy. Chemotherapy, on the other hand, was found to significantly improve disease-specific survival when combined with metastasectomy.

CONCLUSIONS

Undifferentiated sarcoma was the most common source of brain metastasis. Most cases showed evidence of prior metastatic disease. Surgical resection is employed to manage symptoms, but prognosis remains dismal.

Postoperative brain metastases in soft tissue sarcomas

Brain metastases (BMs) from soft tissue sarcoma (STS) are rare but lethal. We reviewed 187 consecutive patients with STS treated with definitive surgery in Nagoya University Hospital from 2004 to 2014. There were 10 patients with neurofibromatosis-1 (NF-1). We investigated estimated brain metastasis free survival (BMFS) after surgery and overall survival (OS) after BMs in STS. The factors that affected BMFS were also investigated. Eight of 187 patients (4.3%) developed BM with a median period of 18.2 (range 8.8-42.6) months after surgery. Seven of 8 BM patients had metastases at other sites. Estimated 5 year BMFS rate after surgery was 95.2%, and 3 month OS rate after BM was 25.0%. NF-1 (p<0.0001), histological subtype of MPNST (p=0.008), and primary tumor size≥5 cm (p=0.021) were significantly associated with increasing incidence of BM. In this study, postoperative BMs were common in patients with NF-1, MPNST, and large tumors. Considering the impact of NF-1 on BMFS, careful follow up for BM is necessary for NF-1 patients with metastases at other sites.

Cranial metastatic alveolar rhabdomyosarcoma mimicking hematological malignancy in an adolescent boy

BACKGROUND

Widespread alveolar rhabdomyosarcoma (ARMS) with bone marrow involvement and with an unknown primary tumor, especially presenting with acute tumor lysis syndrome can be easily misdiagnosed as a hematological malignancy. Furthermore, brain metastasis of ARMS is rare seen in children.

CASE REPORT

Herein, we report a 14-year-old boy presenting with acute tumor lysis syndrome due to bone marrow invasion of ARMS, who was diagnosed after abdominal paraaortic lymph node biopsy. Despite radiological and nuclear medicine imaging, the primary tumor site could not be found. He was treated with vincristine, topotecan, and cyclophosphamide for 42 weeks. Six months after the completion of treatment, he suffered from severe headache, blurred vision, right hemiplegia, and severe bone pain. Cranial magnetic resonance imaging showed multiple hemorrhagic infarctions. Brain biopsy showed brain metastasis with PAX3-FKHR fusion transcript.

CONCLUSION

The clinicians must be vigilant about solely brain metastasis in ARMS without additional metastasis.

Brain metastasis in bone and soft tissue cancers: a review of incidence, interventions, and outcomes

Bone and soft tissue malignancies account for a small portion of brain metastases. In this review, we characterize their incidence, treatments, and prognosis. Most of the data in the literature is based on case reports and small case series. Less than 5% of brain metastases are from bone and soft tissue sarcomas, occurring most commonly in Ewing's sarcoma, malignant fibrous tumors, and osteosarcoma. Mean interval from initial cancer diagnosis to brain metastasis is in the range of 20-30 months, with most being detected before 24 months (osteosarcoma, Ewing sarcoma, chordoma, angiosarcoma, and rhabdomyosarcoma), some at 24-36 months (malignant fibrous tumors, malignant peripheral nerve sheath tumors, and alveolar soft part sarcoma), and a few after 36 months (chondrosarcoma and liposarcoma). Overall mean survival ranges between 7 and 16 months, with the majority surviving < 12 months (Ewing's sarcoma, liposarcoma, malignant fibrous tumors, malignant peripheral nerve sheath tumors, angiosarcoma and chordomas). Management is heterogeneous involving surgery, radiosurgery, radiotherapy, and chemotherapy. While a survival advantage may exist for those given aggressive treatment involving surgical resection, such patients tended to have a favorable preoperative performance status and minimal systemic disease.

Neuropathology of brain metastases

Metastatic tumors are the most common neoplasms encountered in the central nervous system (CNS), and continue to be major cause for mortality and morbidity. Macroscopic features and corresponding radiological findings can be diagnostic in majority of the cases, however, microscopic evaluation would be necessary when the differential diagnosis includes a primary CNS tumor, unknown primary tumor site, and when the resection of the tumor is either considered therapeutic or palliative. The first step in the diagnosis of a metastatic brain lesion is to exclude a primary CNS tumor, followed by verification or identification of the primary tumor and the site. Although general approach to a metastatic lesion from an unknown primary tumor is the same everywhere else, there are slight variations for the metastatic lesions in the CNS versus other regions. When morphological features are not enough to establish a definitive diagnosis, additional studies including immunohistochemical stains are applied. With the expending immunohistochemical armamentarium for pathologists, more accurate assessments are possible even in cases of unknown primary tumor. This review summarizes the diagnostic approach to CNS metastases, immunohistochemical assessment of neoplasm of unknown primary, and primary CNS lesions entering in the differential diagnosis of metastases.

Suspected CNS Metastases of Askin's Tumor: Would You Irradiate the Neural Axis?

We present a case of a young-adult patient who was diagnosed with Askin's tumor, with central nervous system lesions suspected as metastases. The patient achieved complete response after chemotherapy, and the question of consolidation radiotherapy to the CNS is discussed.

Alveolar soft part sarcoma of the frontal calvarium and adjacent frontal lobe

Alveolar soft part sarcoma is a rare tumor affecting mainly adolescent and young children. It presents as a slowly growing tumor and is usually overlooked due to lack of symptoms. Early metastasis is a characteristic feature of this tumor and, in a good number of cases, metastasis to the lung or brain is the first manifestation of the disease. In this report, we present a case of alveolar soft part sarcoma predominantly located in the right frontal bone with dural breach and contiguous right frontal lobe involvement in a 17-year-old girl without any evident primary or other secondaries. A brief review of literature is also presented.