Long-term survival in patients with primary malignant brain tumors after postoperative home hydrogen inhalation: Three case reports

Figure 1 Pathological image of cerebellar medulloblastoma. A: Hematoxylin and eosin (HE) staining, × 200 magnification; B: HE staining, × 400 magnification (provided by the First Affiliated Hospital of Xi’an Jiaotong University, China).

Figure 2 Pathological image of thalamic glioblastoma. A: Hematoxylin and eosin (HE) staining, × 100 magnification; B: HE staining, × 200 magnification (provided by the Pathology Department, West Campus of Huashan Hospital, Fudan University, Shanghai, China).

Figure 3 Head magnetic resonance imaging in June 2021 showing space-occupying lesions on T1-weighted imaging in the cerebellar vermis and bilateral cerebellar hemispheres (orange arrows). A: Axial section; B: Sagittal section (provided by Tangdu Hospital, Air Force Medical University, Xi’an, China).

Figure 4 Cranial magnetic resonance imaging showing a T1 hypointense area in the right thalamus (orange arrow). A: Axial section; B: Sagittal section [provided by Huashan Hospital (West Campus), affiliated to Fudan University, Shanghai, China].

Figure 5 Magnetic resonance imaging before hydrogen inhalation showing an enlarged residual tumor (45 mm × 27 mm) in the left frontal lobe on T1-weighted imaging. A: Axial section; B: Coronal section (provided by Cancer Hospital Affiliated to Sun Yat-sen University, Guangzhou, China).

Figure 6 Cranial magnetic resonance imaging showed no obvious enhancing abnormal lesions in T1-weighted imaging. A: Axial section in July 2022; B: Sagittal section in July 2022; C: Axial section in November 2024; D: Sagittal section in November 2024 (provided by the First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, China).

Figure 7 Cranial magnetic resonance imaging performed in November 2022 showed patchy low signals on T1-weighted imaging and mixed signals on fluid-attenuated inversion recovery sequence in the surgical area, suggesting possible postoperative changes or tumor recurrence. A: Follow up cranial magnetic resonance imaging (MRI)-axial section in November 2022; B: Follow up cranial MRI-sagittal section in November 2022; C: Follow up cranial MRI-axial section in December 2023 revealing no obvious enhancing lesions; D: Follow up cranial MRI-sagittal section in December 2023 revealing no obvious enhancing lesions; E: Follow up cranial MRI-axial section in September 2025 revealing no obvious enhancing lesions; F: Follow up cranial MRI-sagittal section in September 2025 revealing no obvious enhancing lesions (provided by the West Campus of Huashan Hospital, affiliated to Fudan University, Shanghai, China).

Figure 8 Changes in the maximum diameter of the tumor observed on magnetic resonance imaging re-examination after the diagnosis of anaplastic oligoastrocytoma. MRI: Magnetic resonance imaging; AOA: Anaplastic oligoastrocytoma; H₂: Hydrogen.

Figure 9 A series of brain magnetic resonance imaging scans after hydrogen intervention showed gradual tumor regression until disappearance. A and B: In November 2019, 9 months after combined hydrogen intervention, T1-weighted magnetic resonance imaging (MRI) revealed a 37 mm × 24 mm tumor in the left frontal lobe (orange arrow), accompanied by mild ventricular dilation and fluid accumulation; C and D: In May 2021, 8 months after hydrogen monotherapy, T1-weighted cranial MRI showed reduced tumor size compared with the previous; E and F: In July 2024, 46 months after hydrogen monotherapy, supratentorial ventricular system hydrocephalus was observed, with no obvious tumor signs on T1-weighted images (A, C, E: Axial section; B, D, F: Coronal section (provided by Cancer Hospital Affiliated to Sun Yat-sen University, Guangzhou, China).