Malignant transformation of central neurocytoma with dissemination 17 years after initial treatment: illustrative case

BACKGROUND: Central neurocytomas usually have a favorable clinical course, and gross total resection (GTR) results in long-term survival. Recurrences of central neurocytomas are usually local, and dissemination is extremely rare. OBSERVATIONS: A 24-year-old man who presented with vomiting was found to have a mass in the right lateral ventricle. After GTR, he received whole-brain irradiation and chemotherapy and had remained disease-free on follow-up for years. The review of the initial tumor revealed central neurocytoma. Seventeen years later, he presented with deterioration of memory, and magnetic resonance imaging showed an enhanced lesion in the left hippocampus. The enhanced lesion was resected, and the histological examination revealed that the tumor was a disseminated atypical central neurocytoma with frequent mitoses. Although he was treated with chemotherapy, the disseminated tumor slowly grew and invaded the brain. Massive brain invasion occurred without enhanced lesions, and he died 27 months after the tumor recurrence. LESSONS: In this patient, a central neurocytoma disseminated after an extremely long period of time. Once neurocytomas disseminate and show aggressive behavior, patients usually follow a poor course. Patients with central neurocytomas should be followed up for a long time

Central nervous system mature teratoma producing carbohydrate antigen 19-9: illustrative case

BACKGROUND: Central nervous system (CNS) mature teratoma is a rare disease with symptoms that can vary according to tumor location. Most lesions are benign; rarely, malignancy can develop in any of the somatic components. Elevated levels of tumor markers such as α-fetoprotein and β-human chorionic gonadotropin are not usually found in patients with CNS mature teratoma, and no reports have described an association with carbohydrate antigen 19-9 (CA19-9). OBSERVATIONS: A 64-year-old woman with headache was found to have a mass lesion in the anterior cranial fossa. Magnetic resonance imaging of the brain suggested a mature teratoma. Serum and cerebrospinal fluid (CSF) tests showed significant CA19-9 elevations (2, 770 U/mL and 4, 387 U/mL, respectively). Other examinations, including whole-body 18F-fluorodeoxyglucose positron emission tomography, did not detect the origin of elevated CA19-9, suggesting that the high CA19-9 levels were caused by intracranial tumor. The patient underwent tumor removal. The histopathological diagnosis was mature teratoma with positive CA19-9 staining. CA19-9 levels in serum and CSF decreased significantly after tumor removal. LESSONS: The histopathological findings and postoperative decreased CA19-9 levels established the diagnosis of CA19-9-producing CNS mature teratoma. CNS mature teratoma can cause elevations in CA19-9 in cases with absence of neoplasms in the trunk

Papillary glioneuronal tumor growing slowly for 26 years: illustrative case

BACKGROUND: Papillary glioneuronal tumors (PGNTs) are classified as a type of World Health Organization grade I mixed neuronal-glial tumor. Most PGNTs involve cystic formations with mural nodules and solid components in the cerebral hemispheres, and PGNTs occur mainly in young adults. The long-term prognosis of PGNTs remains unclear. OBSERVATIONS: A 38-year-old male had been diagnosed with an arachnoid cyst associated with epilepsy in a local hospital. The initial magnetic resonance imaging (MRI) study showed the tumor as a heterogeneously enhanced nodule in the left postcentral gyrus. Subsequent MRI studies showed slow growth of the tumor for 26 years. He underwent gross total resection to control his epilepsy. The histopathological findings revealed pseudopapillary structures involving hyalinized blood vessels with a single or pseudostratified layer of cuboidal glial cells with round nuclei and scant cytoplasm. At the periphery of the lesion, Rosenthal fibers and acidophilic granule bodies were observed in the gliotic brain tissue. Immunohistochemically, some interpapillary cells were positive for NeuN. On the basis of these findings, the tumor was diagnosed as a PGNT. LESSONS: This PGNT showed slow growth for 26 years. When recognizing a slowly growing tumor in the cerebral hemispheres of relatively young people that is associated with epileptic seizures, PGNT should be considered as a differential diagnosis

Detecting immunoglobulin G4-related intracranial arteriopathy with magnetic resonance vessel wall imaging: a preliminary experience in two cases

[Background] Detecting immunoglobulin G4 (IgG4)-related intracranial arteriopathy, a rare neurovascular complication of IgG4-related disease, is challenging. While magnetic resonance (MR) vessel wall imaging (VWI) can visualize various neurovascular pathologies, its application to this arteriopathy has not been reported as of this writing. [Case presentation] A 74-year-old male and a 65-year-old female manifested multiple cranial nerve palsy and neck pain, respectively. Both cases exhibited multiorgan masses with markedly elevated serum IgG4 levels and were clinically diagnosed with IgG4-related disease. Three-dimensional T1-weighted black blood VWI with and without contrast agent identified intracranial vascular lesions characterized as nearly-circumferential mural thickening with homogeneous contrast enhancement in the internal carotid and vertebral arteries; some of the lesions had been unrecognized with screening MR angiography due to expansive remodeling. The former patient underwent corticosteroid therapy, and VWI after treatment revealed decreased mural thickening and enhancement. [Conclusion] Further studies to elucidate characteristic findings of VWI might contribute to early detection of this treatable pathology

Preoperative obliteration of choroidal arteries in the treatment of large hypervascular tumors in the lateral ventricle

BACKGROUND: Removal of large hypervascular tumors in the lateral ventricle still poses a surgical challenge. These tumors are usually fed from choroidal arteries, and vascular control is typically performed late during the removal. We aimed to evaluate the clinical efficacy of our strategy for persistent preoperative obliteration of feeders from the choroidal arteries to manage large hypervascular tumors in the lateral ventricle. METHODS: We retrospectively analyzed six patients with hypervascular tumors in the lateral ventricle. We first attempted to obstruct feeders using endovascular treatment, and, if unavailable, performed initial microsurgical occlusion through the temporal horn for the staged tumor removal. RESULTS: In all patients, feeder obliteration was successfully performed; the anterior choroidal arteries were occluded by the endovascular treatment and microsurgical occlusion in one and five patients, respectively, while the lateral posterior choroidal arteries were occluded via endovascular treatment in four patients. No patients had permanent symptoms due to feeder obliteration, and tumor devascularization was achieved at the mean rate of 69.9%. During the tumor removal, the mean blood loss volume was 253 ml. No postoperative hemorrhage had occurred, and all patients scored ≤ 2 on the modified Rankin Scale at six months post-removal. CONCLUSIONS: Although further studies are warranted, persistent feeder obliteration of choroidal arteries could be an effective treatment strategy against large hypervascular tumors in the lateral ventricle

Mixed germ cell tumor infiltrating the pineal gland without elevated tumor markers: illustrative case

BACKGROUND: Tumors in the pineal region consist of various histological types, and correct diagnosis from biopsy specimens is sometimes difficult. The authors report the case of a patient with a mixed germ cell tumor infiltrating into the pineal gland despite showing no elevation of tumor markers. OBSERVATIONS: An 18-year-old man complained of headache and nausea and showed disturbance of consciousness. Magnetic resonance imaging showed hydrocephalus associated with a cystic pineal tumor. The patient underwent tumor biopsy followed by endoscopic third ventriculostomy for hydrocephalus in a local hospital. A pineocytoma was diagnosed, and the patient was referred to the authors' hospital for treatment. Concentrations of placental alkaline phosphatase, alpha-fetoprotein (AFP), and beta-human chorionic gonadotropin in cerebrospinal fluid were not elevated. However, the authors' review of the tumor specimen revealed some immature cells infiltrating the pineal gland. These cells were positive for AFP, Sal-like protein 4, and octamer-binding transcription factor 3/4; and the diagnosis was changed to mixed germ cell tumor. Chemoradiotherapy was initiated, followed by surgical removal of the residual tumor. LESSONS: Careful examination of all tumor specimens and immunohistochemical analyses are important for accurate diagnosis of pineal tumors

Infrequent RAS mutation is not associated with specific histological phenotype in gliomas

BACKGROUND: Mutations in driver genes such as IDH and BRAF have been identified in gliomas. Meanwhile, dysregulations in the p53, RB1, and MAPK and/or PI3K pathways are involved in the molecular pathogenesis of glioblastoma. RAS family genes activate MAPK through activation of RAF and PI3K to promote cell proliferation. RAS mutations are a well-known driver of mutation in many types of cancers, but knowledge of their significance for glioma is insufficient. The purpose of this study was to reveal the frequency and the clinical phenotype of RAS mutant in gliomas. METHODS: This study analysed RAS mutations and their clinical significance in 242 gliomas that were stored as unfixed or cryopreserved specimens removed at Kyoto University and Osaka National Hospital between May 2006 and October 2017. The hot spots mutation of IDH1/2, H3F3A, HIST1H3B, and TERT promoter and exon 2 and exon 3 of KRAS, HRAS, and NRAS were analysed with Sanger sequencing method, and 1p/19q codeletion was analysed with multiplex ligation-dependent probe amplification. DNA methylation array was performed in some RAS mutant tumours to improve accuracy of diagnosis. RESULTS: RAS mutations were identified in four gliomas with three KRAS mutations and one NRAS mutation in one anaplastic oligodendroglioma, two anaplastic astrocytomas (IDH wild-type in each), and one ganglioglioma. RAS-mutant gliomas were identified with various types of glioma histology. CONCLUSION: RAS mutation appears infrequent, and it is not associated with any specific histological phenotype of glioma

Narrow safety range of intraoperative rectal irradiation exposure volume for avoiding bleeding after seed implant brachytherapy

<p>Abstract</p> <p>Background & Purpose</p> <p>Rectal toxicity is less common after ¹²⁵I seed implant brachytherapy for prostate cancer, and intraoperative rectal dose-volume constraints (the constraint) is still undetermined in pioneering studies. As our constraint failed to prevent grade 2 or 3 rectal bleeding (bled-pts) in 5.1% of patients, we retrospectively explored another constraint for the prevention of rectal bleeding.</p> <p>Materials and methods</p> <p>The study population consisted of 197 patients treated with the brachytherapy as monotherapy using real-time intraoperative transrectal ultrasound (US)-guided treatment at a prescribed dose of 145 Gy. Post-implant dosimetry was performed on Day 1 and Day 30 after implantation using computed tomography (CT) imaging. Rectal bleeding toxicity was classified by CTC-AE ver. 3.0 during a mean 29-month (range, 12-48 months) period after implantation. The differences in rV100s were compared among intraoperative, Day 1 and Day 30 dosimetry, and between that of patients with grade 2 or 3 rectal bleeding (the bled-pts) and of the others (the spared-pts). All patients were divided into groups based on provisional rV100s that were increased stepwise in 0.1-cc increments from 0 to 1.0 cc. The difference in the ratios of the bled-pts to the spared-pts was tested by chi-square tests, and their odds ratios were calculated (bled-OR). All statistical analyses were performed by <it>t</it>-tests.</p> <p>Results</p> <p>The mean values of rV100us, rV100CT_1, and rV100CT_30 were 0.31 ± 0.43, 0.22 ± 0.36, and 0.59 ± 0.68 cc, respectively. These values temporarily decreased (p = 0.020) on Day 1 and increased (p = 0.000) on Day 30. There was no significant difference in rV100s between the bled-pts and spared-pts at any time of dosimetry. The maximum bled-OR was identified among patients with an rV100us value above 0.1 cc (p = 0.025; OR = 7.8; 95% CI, 1.4-145.8); an rV100CT_1 value above 0.3 cc (p = 0.014; OR = 16.2; 95% CI, 3.9-110.7), and an rV100CT_30 value above 0.5 cc (p = 0.019; OR = 6.3; 95% CI, 1.5-42.3).</p> <p>Conclusion</p> <p>By retrospective analysis exploring rV100 as intraoperative rectal dose-volume thresholds in ¹²⁵I seed implant brachytherapy for prostate cancer, it is proved that rV100 should be less than 0.1 cc for preventing rectal bleeding.</p