Anaplastic ependymoma metastases though a ventriculoperitoneal shunt

Disappearance of "Elongated Pony Tail Sign" Following Chemoradiotherapy in a Case of Primary Cerebellopontine Angle Ependymoma With Spinal Drop Metastasis: 18 F-FDG PET/CT Scan Findings

ABSTRACT

Ependymomas are rare glial tumors that commonly arise from the lining cells of ventricular system and constitute ~10% of intracranial pediatric malignancies. The incidence of ependymoma in adults is rare. Due to close approximation with the ventricular system, subtentorial ependymomas are more prone to show cerebrospinal fluid metastasis compared with supratentorial ependymomas. We present a case of subtentorial cerebellopontine angle ependymoma with diffuse spinal drop metastases showing "elongated pony tail appearance" in a 69-year-old man with complete metabolic response on 18 F-FDG PET/CT imaging following chemoradiotherapy.

A Pediatric Case of Extraneural Subcutaneous Metastasis of Ependymoma

Ependymoma is the third most common brain tumor in children. Extracranial metastases of ependymomas are uncommon. A 21-month-old Japanese boy was diagnosed to be brain dead due to a posterior fossa (PF) brain tumor. Surgical resection of the tumor was not performed. Twenty-seven months later, he developed a truncal subcutaneous tumor, which was pathologically diagnosed as PF ependymoma group A. We observed the intracranial recurrence of the brain tumor, an invasion to the left orbit, and a neoplasm in his liver before he died. This case suggests that PF ependymoma group A can metastasize extracranially to various organs.

Patterns of Extraneural Metastases in Children With Ependymoma

Ependymomas account for 10% of all malignant pediatric central nervous system tumors. Standard therapy includes maximal safe surgical resection, followed by focal radiation. Despite the aggressive therapy, progression-free survival is poor. Most ependymoma relapses occur locally at the original tumor site. Extraneural presentations of ependymoma are extremely rare, and no standard of care treatment exists. We present a single-institution case series of 3 patients who experienced extraneural relapses of supratentorial ependymoma and describe their treatment and outcome. These cases of extraneural relapse highlight the possible modes of extraneural spread, including hematogenous, lymphatic, and microscopic seeding through surgical drains and shunts. In addition, they illustrate the increase in histologic grade and mutational burden that may occur at the time of relapse. These cases illustrate the role of aggressive, individualized treatment interventions using a combination of surgery, radiation, and chemotherapy.

Imaging of pre- and post-cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for pediatric intraperitoneal malignancy

Although rare, pediatric peritoneal carcinomatosis does occur in primary abdominopelvic tumors. Additionally, peritoneal carcinomatosis has been described to occur as metastatic disease where the primary tumor is outside the abdominopelvic cavity. Where amenable, cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) can be beneficial in disease management. However, favorable outcomes are predicated on specific tumor histology as well as proper patient selection, which significantly relies on preoperative imaging. This review gives a comprehensive, up-to-date summary on pediatric peritoneal carcinomatosis pre-surgical evaluation; where imaging is beneficial and limited; pediatric radiologists' role in helping to quantify disease; and how we, as pediatric radiologists, can help the surgeons and oncologists in the selection of patients for cytoreductive surgery and HIPEC.

Extra-Neural Metastases From Primary Intracranial Ependymomas: A Systematic Review

Background

Primary intracranial ependymomas (IE) are rare brain tumors rarely metastasizing outside the central nervous system. We systematically reviewed the literature on extra-neural metastases from primary IEs.

Methods

PubMed, Scopus, Web-of-Science, and Cochrane were searched following the PRISMA guidelines to include studies of extra-neural metastases from primary IEs. Clinical features, management strategies, and survival were analyzed.

Results

We collected 48 patients from 43 studies. Median age was 13 years (range, 2-65). Primary IEs were frequently located in the parietal (22.9%) and frontal (16.7%) lobes, and mostly treated with resection (95.8%) and/or radiotherapy (62.5%). Most IEs were of grade-III (79.1%), and few of grade-I (6.3%) or grade-II (14.6%). 45 patients experienced intracranial recurrences, mostly treated with resection (86.7%), radiotherapy (60%), and/or chemotherapy (24.4%). Median time-interval from primary IEs was 28 months (range, 0-140). Most extra-neural metastases were diagnosed at imaging (37.5%) or autopsy (35.4%). Extra-neural metastases were multifocal in 38 patients (79.1%), mostly involving cervical or hilar lymph-nodes (66.7%), lung/pleura (47.9%), and/or scalp (29.1%). Surgical resection (31.3%), chemotherapy (31.3%) and locoregional radiotherapy (18.8%) were the most common treatments for extra-neural metastases, but 28 (58.3%) patients were not treated. At last follow-up, 37 patients died with median overall-survivals from primary IEs of 36 months (range, 1-239), and from extra-neural metastases of 3 months (range, 0.1-36). Overall-survival was significantly longer in patients with grade-I and II IEs (P=0.040).

Conclusion

Extra-neural metastases from primary IEs are rare, but mostly occur at later disease stages. Multidisciplinary management strategies should be intended mostly for palliation.