Leptomeningeal metastases (LM) are a rare but rapidly fatal complication defined by the spread of tumor cells within the leptomeninges and the subarachnoid space, found in approximately 10% of patients with HER2-positive breast cancers. This pilot study evaluated the efficacy of local treatment with intrathecal Trastuzumab (IT) added to systemic treatment. The oncologic outcome of 14 patients with HER2-positive LM is reported. Seven received IT, and seven received standard of care (SOC). The mean number of IT cycles administered was 12.14 ± 4.00. The response rate to CNS after IT treatment + SOC was 71.4%, and three patients (42.8%) obtained durable responses lasting more than 12 months. The median progression-free survival (mPFS) after LM diagnosis was six months, and the median overall survival (mOS) was ten months. The mean values of the PFS in favor of IT therapy (10.6 mo vs. 6.6 mo) and OS (13.7 vs. 9.3 mo) suggest a non-negligible investigation direction in the sense of exploiting intrathecal administration as a possible treatment modality in these patients. Adverse events reported were local pain related to intrathecal administration and one case of arachnoiditis, hematoma, and CSF fistulae. Intrathecal administration of Trastuzumab, alongside systemic treatment and radiotherapy, might improve oncologic outcomes in LM HER2-positive breast cancer with manageable toxicity.

In 2021, the 5th edition of the WHO Classification of Tumors of the Central Nervous System (WHO-CNS5) was published as the sixth volume of the international standard for brain and spinal cord tumor classification. The most remarkable practical change in the current classification involves grading gliomas according to molecular characterization. IDH mutant (10%) and IDH wild-type tumors (90%) are two different entities that possess unique biological features and various clinical outcomes regarding treatment response and overall survival. This article presents two comparative cases that highlight the clinical importance of these new classification standards. The first clinical case aimed to provide a comprehensive argument for determining the IDH status in tumors initially appearing as low-grade astrocytoma upon histologic examination, thus underlining the importance of the WHO-CNS5. The second case showed the implications of the histologic overdiagnosis of glioblastoma using the previous classification system with a treatment span of 7 years that proceeded through full-dose re-irradiation up to metronomic therapy. The new WHO-CNS5 classification significantly impacted complex neurooncological cases, thus changing the initial approach to a more precise therapeutic management.

Background: Brain radiation necrosis is a side effect of radiotherapy that can occur months, or even years, after the end of treatment. From an anatomical–pathological perspective, it is characterized by avascular damage, demyelination, and necrosis. Methods: We present a case of a patient with breast cancer cT2N1M0 and multiple brain metastases occurring at 2 years after diagnosis, who was treated with whole-brain radiotherapy (WBRT) and Stereotactic Radiotherapy (SRT) for tumor progression. Dynamic imaging revealed right parietal post-therapeutic changes in aggravation, requiring differential diagnosis between tumor progression (TP) and brain radionecrosis (BRN). Results: Brain radionecrosis and tumor progression are difficult to differentiate due to their similar radiological and clinical characteristics. MRI perfusion plays an important role in differentiating the two entities. Conclusions: Differentiating radiation necrosis from a recurrent tumor is crucial for appropriate treatment. Medical management includes corticosteroids as first-line treatment, after which bevacizumab is administered as secondary therapy.

Background/Objectives: The independent contribution of extent of resection (EOR) to early recurrence in diffuse gliomas remains debated, as crude analyses are confounded by tumor biology, and real-world data from Eastern European centers are scarce. Methods: We retrospectively studied 283 consecutive adults with surgically treated diffuse gliomas (2021–2024) at a Romanian tertiary center. Primary endpoints were recurrence-free survival (RFS) at 1 and 2 years, evaluated as landmark endpoints; secondary endpoints were overall recurrence, reoperation, and reirradiation. Clinical, histopathological, surgical, imaging, and treatment variables were analyzed with complete-case Firth-penalized logistic regression. Results: Among evaluable patients, 70.6% (132/187) were recurrence-free at 1 year and 64.2% (120/187) at 2 years; overall recurrence occurred in 53.7% (139/259). After adjustment, gross total resection (GTR) was independently associated with higher odds of remaining recurrence-free at 1 year (OR 12.37, 95% CI 3.23–52.58; p < 0.001) and 2 years (OR 10.56; p < 0.001), as was subtotal resection (STR) at both time points (OR 4.15, 95% CI 1.17–16.16, p = 0.027; and OR 3.93, p = 0.027), versus partial resection/biopsy. Conclusions: EOR was independently associated with early RFS, supporting maximal safe resection as a primary surgical objective. The landmark endpoints were not evaluable in 96 of 283 patients, almost all of whom underwent biopsy or partial resection, so the odds ratios indicate the direction of the effect and not its precise magnitude. Overall recurrence, evaluable in 91.5% of the cohort, showed a concordant gradient. External validation is needed.

Background and Objectives: Magnetic resonance imaging (MRI) is essential for monitoring patients with diffuse gliomas after surgery and adjuvant therapy. However, the prognostic significance of imaging findings observed on the first post-treatment MRI remains incompletely defined in routine clinical practice. This study aimed to evaluate whether MRI features identified on the first post-treatment examination are associated with recurrence-free survival after near-total resection (NTR), defined for this real-world cohort as ≥80% volumetric tumor removal (which differs from the RANO Resect Group definition of GTR). Materials and Methods: Consecutive adult patients with histologically confirmed diffuse gliomas diagnosed between 2021 and 2024 were screened for eligibility (n = 283) and classified according to the 2021 WHO Classification of Tumors of the Central Nervous System. The first post-treatment MRI was defined as the earliest follow-up examination performed after completion of all initially planned therapy (surgery alone in patients without indication for adjuvant therapy; post-radiotherapy ± chemotherapy in the remaining patients), and not the immediate postoperative scan. Patients with available first post-treatment MRI were included (n = 149), resulting in a final cohort of 139 cases after exclusion of outliers. The evaluated MRI corresponded to the first follow-up examination after treatment (mean interval ~120 days after surgery). Logistic regression models were used to assess associations between post-treatment MRI features and recurrence-free survival at one and two years after NTR, with exploratory analyses for reoperation and reirradiation. Results: Residual tumor identified on the first post-treatment MRI was associated with lower odds of recurrence-free survival (RFS) at one and two years after NTR. Postoperative functional status also demonstrated an independent association with tumor control. Other imaging variables showed associations in univariable analyses but did not remain independent predictors after adjustment. Exploratory analyses of reoperation and reirradiation suggested additional clinical influences, including patient age. Conclusions: In this real-world cohort with heterogeneous tumor subtypes and treatment regimens, residual tumor on first follow-up MRI was the most consistent imaging correlate of reduced RFS, alongside postoperative functional status. These hypothesis-generating findings should be validated in stratified, prospective cohorts.