Primary rhabdomyosarcoma associated with tumoral hemorrhage--case report

Two cases of primary supratentorial intracranial rhabdomyosarcoma with DICER1 mutation which may belong to a "spindle cell sarcoma with rhabdomyosarcoma-like feature, DICER1 mutant"

Rhabdomyosarcoma is the most common soft-tissue sarcoma affecting children and adolescents. It is defined as a malignant neoplasm characterized by morphologic, immunohistochemical, ultrastructural, or molecular genetic evidence of primary skeletal muscle differentiation, usually in the absence of any other pattern of differentiation. Primary intracranial rhabdomyosarcoma (PIRMS) is an extremely rare neoplasm, with only 60 cases reported in the literature, and generally has poor prognosis with an overall survival of only 9.1 months. The DICER1 gene encodes an RNA endoribonuclease that plays a key role in gene expression regulation through the production of small RNAs. Herein, we report two cases of PIRMS with somatic DICER1 mutation showing morphological and immunohistochemical evidence of primary skeletal muscle differentiation; the two cases share common clinical features, including young age, supratentorial tumor, and onset of intratumoral bleeding. Although methylation profiling was not performed, both cases shared clinical and pathological characteristics in common with recently proposed methylation entity "spindle cell sarcoma with rhabdomyosarcoma-like features, DICER1 mutant (SCS-RMSlike-DICER1)''. Our cases provide further evidence of the link between primary intracranial sarcoma and DICER1 mutation which may form a distinct entity.

Prevalence and Surgical Implications of Dural Enhancement at the Porus Acusticus in Vestibular Schwannomas

OBJECTIVE

Demonstrate the association of radiographic dural enhancement with increased tumor adherence at the porus acusticus, which may influence completeness of resection and facial nerve outcome.

STUDY DESIGN

Case series with chart review.

SETTING

Academic referral center.

SUBJECTS AND METHODS

A total of 205 consecutive patients with histopathologically confirmed vestibular schwannoma (VS) were evaluated. Patients with tumors exhibiting dural enhancement on postgadolinium T1-weighted magnetic resonance imaging were identified and compared with matched controls. Completeness of resection, intraoperative details, and facial nerve outcomes were analyzed.

RESULTS

Excluding strictly intracanalicular tumors (n = 32, 16%) and those with NF2 (n = 10, 4.9%), the presence of dural enhancement was radiographically confirmed in 16 (9.8%) cases. Paired analysis did not reveal significant baseline differences between cases and controls. Subtotal resection was performed in 5 (31%) of the 16 patients with tumors exhibiting dural enhancement, in contrast to 1 (3%) of the matched controls (P = .01). Four (25%) demonstrated increased tumor adherence at the porus acusticus intraoperatively, compared with 1 control (3%, P = .04). Long-term facial nerve function was similar between cases and controls (81% vs 84% House-Brackmann I-II function, P = 1.00).

CONCLUSION

Dural enhancement is present in approximately 10% of extracanalicular VS. Dural enhancement at the porus acusticus may represent hypervascularity, dural reaction, or infiltration, and portends increased tumor adherence and greater likelihood of subtotal resection to preserve facial nerve function. To our knowledge, this is the first series that reports the prevalence of this phenomenon in VS and the potential surgical implications. Recognition preoperatively may be valuable toward patient counseling.

A review on dural tail sign

“Dural tail sign” (DTS) which is a thickening of the dura adjacent to an intracranial pathology on contrast-enhanced T1 MR Images, was first thought to be pathognomonic of meningioma, however, many subsequent studies demonstrated this sign adjacent to various intra- and extra-cranial pathologies and in spinal lesions. In this paper we outline the history, accompanying pathologies and the differentiation and probable pathophysiology of DTS. We also discuss whether we can predict tumoral involvement of the dural tail before surgery and whether the dural tail adjacent to a tumor should be resected.

Primary intracranial dural-based synovial sarcoma with an unusual SYT fluorescence in situ hybridization pattern

The authors present the case of an elderly man with a primary dural-based intracranial synovial sarcoma. Histological and immunohistochemical profiles of the lesion were diagnostic for a synovial sarcoma, and molecular studies using fluorescence in situ hybridization were compatible with a synovial sarcoma. A wide array of spindle cell neoplasms has been described as originating in the dura. To the authors' knowledge, however, this is only the second primary durabased intracranial synovial sarcoma ever reported, emphasizing the importance of a broad differential diagnosis when encountering spindle cell lesions of the meninges.

CHRONIC SUBDURAL HEMATOMA ASSOCIATED WITH SUBDURAL RHABDOMYOSARCOMA

OBJECTIVE

Subdural rhabdomyosarcoma is very rare, and even more unusual is the association between these sarcomas and chronic subdural hematoma. In this report, we present a case of subdural rhabdomyosarcoma that developed in a chronic refractory subdural hematoma.

CLINICAL PRESENTATION

A 40-day-old boy was admitted with coma and intractable seizure after a head trauma caused by a fall. A subdural hematoma was detected, which later became chronic and refractory to treatment.

INTERVENTION

The patient repeatedly underwent different surgical interventions over 2 years. Finally, extensive bilateral frontotemporoparietal craniotomy was performed at the age of 30 months, which revealed a huge subdural mass. The mass and membranes were resected. Pathological examination confirmed the diagnosis of embryonal-type rhabdomyosarcoma. Radiation therapy was performed, but the tumor recurred and the child died at the age of 3 years.

CONCLUSION

Whether the subdural hematoma or the tumor was the initial pathology is debatable. We think the sarcoma probably developed gradually because of chronic inflammation and proliferation in the subdural collection.