Imaging findings of a metastatic myxopapillary ependymoma in the left inguinal region

.

CTIM-32. IMMUNE CHECKPOINT INHIBITOR NIVOLUMAB IN PEOPLE WITH RECURRENT SELECT RARE CNS CANCERS: RESULTS OF INTERIM ANALYSIS IN A HEAVILY PRETREATED COHORT

INTRODUCTION Standard and experimental therapies for patients with rare CNS tumors are scarce. Nivolumab (PD-1 inhibitor) is approved for several non-CNS cancers. This ongoing Phase II trial (NCT03173950) will determine the efficacy of nivolumab in adults with recurrence/progression of one of 11 selected rare primary CNS tumors. Efficacy is measured by Disease Control Rate (DCR; confirmed CR/PR or durable SD for ≥ 6 months) in 2 cohorts: heavily and non-heavily pretreated patients (heavily pretreated: ≥ 3 prior therapies; non-heavily pretreated: ≤ 2). We report efficacy and safety results of a preplanned interim analysis in the heavily pretreated cohort. METHODS Eligibility includes recurrence/progression of an eligible tumor; age ≥ 18 years; tumor tissue available for histopathology, molecular and immune profiling; KPS ≥ 70; and no steroids at study entry. A total of 150 evaluable patients will be enrolled (75 to each cohort). Prior therapies include radiation and/or standard or investigational drugs. Nivolumab treatment is 240 mg IV every 2 weeks (4 doses); then 480 mg every 4 weeks (14 additional doses). Interim analysis was planned when sample size reached 32 in each cohort. RESULTS As of March 10, 2021, DCR exceeded the minimum required for interim analysis in the heavily pretreated cohort. Among 30 patients, 4 achieved SD > 6 months (medulloblastoma, anaplastic ependymoma, myxopapillary ependymoma, metastatic atypical meningioma). Safety profile (related AEs): grade 3 = 7; grade 4 = 1. Most frequent grade 3-5 AEs regardless of attribution: tumor progression (6); anemia, hydrocephalus, lymphopenia (3 each); cerebral edema, headache (2 each). CONCLUSION DCR exceeded the “go” boundary (i.e., > 2) in the heavily pretreated cohort. Nivolumab showed safety profile consistent with other studies. This cohort will continue to stage 2 and complete total accrual of 75 patients. The trial is currently being expanded to 10 additional sites across the BTTC/NCI-CONNECT consortium.

Rare sacral extradural grade II ependymoma: a comprehensive review of literature

Sacral spinal cord ependymoma is an uncommon pathology. Most of the reported cases are consistent with a myxopapillary ependymoma histopathologic subtype. Non-myxopapillary ependymomas rarely occur in the sacral region. Most lesions are intradural; however, rare extradural cases can occur. We present the case of a 46-year-old female patient diagnosed with a grade II sacral extradural ependymoma, emphasising the importance of an interdepartmental case approach for diagnosis and management. Even though grade II ependymomas are considered low grade, the potential for recurrence and metastatic disease has been reported. There are no treatment guidelines for these rare tumours besides gross total resection.

Cauda equina ependymomas: surgical treatment and long-term outcomes in a series of 125 patients

OBJECTIVE Cauda equina ependymoma (CEE) is a rare tumor for which little information is available on the oncological and clinical outcomes of patients. In this study the authors aimed to address functional, oncological, and quality-of-life (QOL) outcomes in a large series of consecutive patients operated on at their institution during the past 20 years. METHODS The records of 125 patients who underwent surgery between January 1998 and September 2018 were reviewed. Analyzed variables included demographic, clinical, radiological, surgical, and histopathological features. Neurological outcomes were graded according to the McCormick and Kesselring scales. The QOL at follow-up was evaluated by administering the EQ-5DL questionnaire. RESULTS On admission, 84% of patients had a McCormick grade of I and 76.8% had a Kesselring score of 0. At follow-up (clinical 8.13 years; radiological 5.87 years) most scores were unchanged. Sacral level involvement (p = 0.029) and tumor size (p = 0.002) were predictors of poor functional outcome at discharge. Tumor size (p = 0.019) and repeated surgery (p < 0.001) were predictors of poor outcome. A preoperative McCormick grade ≥ III and Kesselring grade ≥ 2 were associated with worse outcomes (p = 0.035 and p = 0.002, respectively). Myxopapillary ependymoma (MPE) was more frequent than grade II ependymoma (EII). The overall rate of gross-total resection (GTR) was 91.2% and rates were significantly higher for patients with EII (98%) than for those with MPE (84%) (p = 0.0074). On multivariate analysis, the only factor associated with GTR was the presence of a capsule (p = 0.011). Seventeen patients (13.7%) had recurrences (13 MPE, 4 EII; 76.4% vs 23.6%; p = 0.032). The extent of resection was the only factor associated with recurrence (p = 0.0023) and number of surgeries (p = 0.006). Differences in progression-free survival (PFS) were seen depending on the extent of resection at first operation (p < 0.001), subarachnoid seeding (p = 0.041), piecemeal resection (p = 0.004), and number of spine levels involved (3 [p = 0.016], 4 [p = 0.011], or ≥ 5 [p = 0.013]). At follow-up a higher proportion of EII than MPE patients were disease free (94.7% vs 77.7%; p = 0.007). The QOL results were inferior in almost all areas compared to a control group of subjects from the Italian general population. A McCormick grade ≥ 3 and repeated surgeries were associated with a worse QOL (p = 0.006 and p = 0.017). CONCLUSIONS An early diagnosis of CEE is important because larger tumors are associated with recurrences and worse functional neurological outcomes. Surgery should be performed with the aim of achieving an en bloc GTR. The histological subtype was not directly associated with recurrences, but some of the features more commonly encountered in MPEs were. The outcomes are in most cases favorable, but the mean QOL perception is inferior to that of the general population.