✓Primary skeletal non-Hodgkin lymphoma is rare. The authors report a case of a small lymphocytic B-cell lymphoma of the skull occurring in a 53-year-old man who presented with right-hand apraxia. Initial computed tomography and magnetic resonance imaging revealed a hematoma-mimicking lesion in the left frontoparietal subdural area. A frontotemporoparietal craniectomy and biopsy procedure yielded a diagnosis of small lymphocytic B-cell lymphoma, with a metastatic nodule in the retrobulbar area. Three years after undergoing radiation therapy and surgery, the patient has shown neurological improvement without systemic dissemination of the malignancy. The lesion in this case was misdiagnosed as a subdural hematoma, and shows the importance of including lymphoma in the differential diagnosis of subdural mass lesions.
Sang-Hoon Yoon, Sun Ha Paek, Sung-Hye Park, Dong Gyu Kim and Hee-Won Jung
Won-Sang Cho, Seung-Ki Kim, Sung-Hye Park and Byung-Kyu Cho
Kaposiform hemangioendothelioma (KHE) is a rare vascular tumor of infancy and early childhood that occurs mainly in soft tissue and the retroperitoneum. The pathological characteristics of a KHE are fascicles of spindleshaped endothelial cells and slitlike vascular channels with irregular tumor margins. In spite of benign features such as rare mitoses and a low MIB-1 labeling index, a KHE is categorized as an intermediate malignancy because of local invasiveness into adjacent lymph nodes or organs. Resection is the treatment of choice for this type of tumor and adjuvant medical therapy is prepared for the tumor remnants and the associated Kasabach-Merritt syndrome. In this paper the authors report a case of a KHE without Kasabach-Merritt syndrome arising from the right tentorium cerebelli in a 13-month-old male child. The biological behavior of the tumor, including its pathological traits and clinical course, was malignant in nature. This case may be not only the first intracranial extraaxial KHE, but also the first truly malignant variant. Kaposiform hemangioendothelioma should be considered in the differential diagnosis of intracranial and extraaxial tumors.
Jin Wook Kim, Sung-Hye Park, Sung-Sup Park, Kyu-Chang Wang, Byung-Kyu Cho, So Yeon Kim, Eun Kyung Ra, Chae-Yong Kim and Seung-Ki Kim
✓Fetus-in-fetu is a very rare condition in which one fetus is contained within another. About 100 cases have been reported, and in most of these the fetus was located in the retroperitoneum. The authors describe an extremely rare case of an intracranial fetus-in-fetu in an extraaxial location. This is the eighth intracranial fetus-in-fetu to be reported, the first intracranial extraaxial case, and involves the oldest documented patient with this condition.
Histopathological analysis of the mass revealed a degenerated amnionic membranelike tissue, well-differentiated extremities (including fingerlike structures), skin, matured lungs, well-formed intestines, cerebellar and cerebral tissue, and a notochord with ganglion cells. DNA analysis using short tandem repeat polymorphisms confirmed that the fetus-in-fetu mass and the host infant had heterozygous alleles and were of identical sex and genotype.
Dae Hee Han, Dong Gyu Kim, Je G. Chi, Sung Hye Park, Hee-Won Jung and Young Gyu Kim
✓ The authors present the clinical, radiological, pathological features, and autopsy findings of a patient with malignant triton tumor of the acoustic nerve, which probably arose from a pre-existing acoustic schwannoma. The term “malignant triton tumor” is applied to malignant schwannomas with rhabdomyoblastic differentiation. A cerebellopontine angle tumor with spinal drop metastasis occurred in this patient 10 months after near-total removal of the original tumor.
Kyung Sun Song, Sung-Hye Park, Byung-Kyu Cho, Kyu-Chang Wang, Ji Hoon Phi and Seung-Ki Kim
Meningiomas are rare in children. Chordoid meningioma is a very rare variant, as only 16 cases in children have been reported. The authors report the first case of a chordoid meningioma in the third ventricle.
A 12-year-old boy presented with headache, abnormal behaviors, and ataxia. Brain MR imaging revealed a 2-cm, well-enhanced mass in the third ventricle and hydrocephalus. Positron emission tomography with [18F]fluorodeoxyglucose showed that the mass was hypermetabolic. Gross-total removal of the mass was performed using a left frontal transcortical and transventricular approach. The mass originated from the left caudate head and was connected to the choroid plexus. A chordoid meningioma was diagnosed on the basis of the histological characteristics of the tumor, which was composed of cords and nests of eosinophilic vacuolated cells with an abundant myxoid matrix, similar to the features of a chordoma. A typical focal meningiomatous pattern was observed. The tumor cells were immunoreactive for vimentin and epithelial membrane antigen. The patient's headache and gait disturbance improved after the tumor was removed. The tumor showed no signs of recurrence during 12 months of follow-up.
Ji Hoon Phi, Seung-Ki Kim, Sung-Hye Park, Seok Ho Hong, Kyu-Chang Wang and Byung-Kyu Cho
Immature teratomas of the central nervous system (CNS) are rare neoplasms. Although adjuvant therapy is generally recommended after resection, the exact role of each therapeutic modality is not yet established. The purpose of this study was to analyze the clinicopathological correlation and the role of resection to define the optimal treatment modalities for immature teratomas of the CNS.
Between 1987 and 2002, eight patients underwent radical surgery for a lesion diagnosed as a CNS immature teratoma at the authors' institution. The clinical courses of these patients and the pathological features of their tumors were retrospectively reviewed.
Gross-total resection (GTR) was achieved in six patients at the initial operation. The mean follow-up period was 75 months. Two patients received postoperative adjuvant therapies and two patients did not, against medical advice. None of the four patients experienced recurrence after long-term follow up. Another four patients, all of whom underwent GTR of the tumor, did not receive adjuvant therapy as part of a prospective treatment scheme. One of them exhibited early recurrence and metastasis. The tumor had pathological features denoting a high-grade (Norris Grade III) lesion and neurocytomatous differentiation.
Aggressive resection seems to be of utmost importance in the treatment of immature teratomas of the CNS. Adjuvant chemotherapy and radiotherapy can be deferred if GTR is achieved in low-grade, immature teratomas, but adjuvant therapies may be warranted for high-grade ones.
Ji Yeoun Lee, Bo Sung Kim, Ji Hoon Phi, Hyoung Jin Kang, Sung-Hye Park, Kyu-Chang Wang, Il Han Kim, Byung-Kyu Cho and Seung-Ki Kim
Primary sarcomas of the CNS are rare and are sometimes associated with chronic subdural effusion (SDE). Approximately 10 patients with such presentations have been reported. The authors report the case of a 5-year-old boy with multiple subdural masses and SDE. An SDE had been diagnosed when the patient was 2 months old, and he received a subduroperitoneal shunt when he was 5 months old. Since then, he had been clinically stable and well for 5 years. When he presented with acute headache, nausea, and vomiting, a newly developed tumor was found. Near-total resection of the tumor was performed, and the mass was diagnosed as an embryonal-type rhabdomyosarcoma. The child was given radiation therapy and 13 cycles of chemotherapy and is still free of disease 13 months after surgery.
Chul-Kee Park, Dong-Chul Kim, Sung-Hye Park, Jeong Eun Kim, Sun Ha Paek, Dong Gyu Kim and Hee-Won Jung
Cystic vestibular schwannoma (VS) is a unique subgroup of VSs characterized by unpredictable expansion of the cyst component. Little is known, however, about the mechanism of cyst formation. In this study the authors compared neuroimaging and histological characteristics of cystic with solid VS to determine the pathogenesis of the cystic subgroup.
Two cohorts, one comprising 10 patients with cystic VS and the other comprising 10 patients with solid VS, were studied. Surgery was chosen as the primary treatment in all patients, with no other modality applied. Preoperative magnetic resonance images and histological characteristics of the tumor in patients with cystic VSs were evaluated and compared with those in the group with solid VSs. Differences between the two groups were assessed using the chi-square test. Neuroimaging findings revealed that either fluid-fluid level or hemosiderin deposit was present in all cystic VSs. Histological evidence of microhemorrhage, such as hemosiderinladen macrophages (p = 0.069), hemosiderin deposits (p = 0.019), thrombotic vessels (p = 0.008), and abnormal vessel proliferation (p = 0.006) were more prominent in cystic VSs compared with solid ones. There was no difference in Antoni type dominance and Ki-67 proliferative index between the two groups.
Intratumoral microhemorrhage is a possible mechanism of pathogenesis in cystic VS.
Byung Chan Lim, Jong Hee Chae, Seung-Ki Kim, Sung-Hye Park, Kyu-Chang Wang, Ji Yeoun Lee and Ji Hoon Phi
Brainstem glioma is a highly devastating disease, and any mass-like lesion in the brainstem can raise suspicion of this diagnosis. However, other inflammatory, demyelinating, or degenerative diseases can mimic brainstem glioma in clinical presentation and imaging features. Therefore, diagnosis based solely on imaging is often insufficient for brainstem lesions and may lead to incorrect diagnosis and treatment.
This case report is the first description of central nervous system aquaporin-4 (AQP4) autoimmunity confined mainly to the brainstem. It demonstrates the wide spectrum of neuroinflammatory diseases in children and highlights the utility of surgical biopsy for suspicious brainstem lesions with atypical imaging features for glioma.
Jung Won Choi, Ji Yeoun Lee, Ji Hoon Phi, Kyu-Chang Wang, Hyun-Tai Chung, Sun Ha Paek, Dong Gyu Kim, Sung-Hye Park and Seung-Ki Kim
Neurofibromatosis Type 2 (NF2) is an autosomal-dominant inherited disease, characterized by multiple neoplasia syndromes, including meningioma, schwannoma, glioma, and ependymoma. In this report, the authors present their clinical experience with pediatric NF2 patients. In particular, they focused on the clinical course of vestibular schwannoma (VS), including the natural growth rate, tumor control, and functional hearing outcomes.
From May 1988 to June 2012, the authors recruited patients who were younger than 18 years and fulfilled the Manchester criteria. In total, 25 patients were enrolled in this study. The authors analyzed the clinical course of these patients. In addition, they measured the natural growth rate of VS before any treatment in these children with NF2. Then, they evaluated the tumor control rate and functional hearing outcomes after the treatment of VS.
The mean age at the onset of NF2-related symptoms was 9.9 ± 4.5 years (mean ± SD, range 1–17 years). The mean age at the diagnosis of NF2 was 12.9 ± 2.9 years (range 5–17 years). The mean follow-up period was 89.3 months (range 12–311 months). As initial manifestations, nonvestibular symptoms were frequently observed in pediatric patients with NF2. The mean natural growth rate of VS was 0.33 ± 0.41 cm3/year (range 0–1.35 cm3/year). The tumor control rate of VS was 35.3% at 3 years after Gamma Knife surgery (GKS). The actuarial rate of useful hearing preservation was 67% in the 1st year and 53% in the 5th year after GKS.
Clinical manifestations in children with NF2 were highly variable, compared with their adult counterparts. The natural growth rate of VS in children is slow, and this oncological feature may explain the diverse clinical manifestations besides vestibular symptoms in children with NF2. The treatment outcome of GKS for VS in children with NF2 was not favorable compared with previous reports of affected adults.