Brain mushroom: A case of osteolytic intraosseous meningioma with transcalvaria herniation

Primary Intraosseous Osteolytic Meningioma with Aggressive Clinical Behaviour: Clinico-Pathologic Correlation and Proposed New Clinical Classification

(1) Introduction: Primary intraosseous osteolytic meningiomas (PIOM) are non-dural-based tumors predominantly presenting an osteolytic component with or without hyperostotic reactions. They are a subset of primary extradural meningiomas (PEM). In this study, we present a peculiar case with a systematic literature review and propose a new classification considering the limitations of previous classification systems. (2) Materials and Methods: Using a systematic search protocol in Google Scholar, PubMed, and Scopus databases, we extracted all case studies on PIOM published from inception to December 2020. A 46-year-old female patient form Dhaka, Bangladesh, was also described. The search protocol was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. (3) Results: Here, we present a 46-year-old female patient with PIOM who successfully underwent bifrontal craniotomy and gross total removal (GTR) of the tumor. At 6-month follow-up, no tumor recurrence was shown. Including our new case, 55 total cases from 47 articles were included in the analysis. PIOMs were in closer frequency among males (56.4%) and females (43.6%). The most common tumor location was the frontal and parietal calvarium, most commonly in the frontal bone (29.1%). Surgical resection was the predominant modality of treatment (87.3%); only 1.8% of patients were treated with radiotherapy, and 5.4% received a combination of surgery and radiotherapy. Gross total resection (GTR) was achieved in 80% of cases. Extracranial extension was reported in 41.8% of cases, dural invasion in 47.3%, and recurrence in 7.3%. Whole-body 68 Ga-DOTATOC PET/CT has also been reported as a useful tool both for differential diagnosis, radiotherapy contouring, and follow-up. Current treatments such as hydroxyurea and bevacizumab have variable success rates. We have also suggested a new classification which would provide a simple common ground for further research in this field. (4) Conclusions: Surgical resection, especially GTR, is the treatment of choice for PIOM, with a high GTR rate and low risk of complications and mortality. More research is needed on the differential diagnosis and specific treatment of PIOM.

Primary intraosseous meningioma of the calvarium: A systematic review

BACKGROUND

Primary intraosseous meningiomas (PIM) of calvarial origin are a small subset of meningiomas that arise from and occur within the calvarial bone. Its definition is often confused with other forms of non-dural based intracranial meningiomas, which has made previously published retrospective reviews heterogenous, non-specific and sometimes inaccurate. We present a systematic review of calvarial PIM.

METHODS

Using a systematic search protocol that included databases such as PubMed, Web of Science and Embase, we extracted all human studies on PIM published from inception to December 2017. This systematic review includes case reports and retrospective reviews that specifically described PIM.

RESULTS

On review of 166 articles identified with the systematic search protocol, 69 articles were analyzed. These comprised of 64 case reports, 1 case series and 4 retrospective reviews. 111 patients with PIM of calvarial origin were analyzed, 58 % of which were females and 42 % males. The mean patient age was 51 years and the frontal bone was the most common tumor location, occurring in 26.1 % of the cases. Surgical resection was the predominant modality of treatment in 97.2 % of the cases, and gross total resection was achieved in 84 % of cases that reported extent of resection. There were no recurrences for grade I meningiomas. However, all grade III meningiomas recurred and 33.3 % of grade II meningiomas showed recurrence with a mean postoperative follow-up interval of 20 months. Statistical analysis using Fisher's exact test showed the recurrence rate to be strongly associated with WHO tumor grade (p-value <0.001).

CONCLUSION

There is statistically significant increased recurrence rate for calvarial PIM of higher grades, and we recommend close follow-up in those cases. Surgical resection remains the overwhelming treatment of choice for calvarial PIM, and it has a high gross total resection rate and low risk of complications and mortality.

Pediatric Orbital Roof Intradiploic Meningioma Operated by Eyebrow Incision

INTRODUCTION

Primary intradiploic meningiomas account for <1% of all osseous calvarial lesions and are categorized as bone tumors. They are frequently observed in the frontotemporal region of the calvarium, anterior cranial fossa, and orbit. We present a case of intradiploic meningioma of the orbital roof, which is rarely observed in the pediatric age-group; it was surgically treated with a unique minimally invasive approach.

CASE PRESENTATION

A 16-year-old male with chief complaints of headache on the right side for approximately 1 year was presented to our clinic. Cranial MRI revealed an intradiploic mass with homogeneous, hypointense contrast patterns on the T1W and T2W images of the right orbital roof. A skin incision was made through the right eyebrow, and the frontal sinus anterior wall was opened by craniotomy. Gross total resection was achieved by reaching the tumor present in the orbital roof. The mass was characterized as psammomatous meningioma by a pathological examination.

DISCUSSION/CONCLUSION

In cranial oncologic surgery, lesion localization and possible pathological diagnosis are essential for the determination of the correct surgical technique. In particular, in pediatric cases, selecting a method that will reduce the need for transfusion, shorten the surgical time, minimize the chances of facial deformity, and facilitate postoperative care will ensure compliance with the correct and appropriate treatment process.

Primary intraosseous osteolytic meningioma: a case report and review of the literature

BACKGROUND

Primary intraosseous meningioma is a subset of extradural meningioma that arises in the bone, and only a few cases have been reported to date.

CASE PRESENTATION

An 80-year-old man presented with decreased hearing on the right side accompanied by a disturbance of balance 10 months prior to admission. Magnetic resonance imaging revealed an 8 × 7 cm osteolytic mass in the right posterior fossa related to the petrous bone, with extension to the cervical region. During surgery, the tumor was found to be located extradurally, with no invasion of the dura. The tumor was removed entirely, apart from a small portion around the jugular foramen to avoid lower cranial nerve injury.

CONCLUSION

The final diagnosis was primary intraosseous osteolytic meningioma with atypical pathology. Here, we report a rare case of an osteolytic skull lesion in the skull base not invading the dura and with extensive bone destruction.