An anaplastic pleomorphic xanthoastrocytoma with periventricular extension: An autopsy case report and review of the literature.

Pleomorphic xanthoastrocytomas (PXAs) are rare low-grade astrocytic tumors that typically present as superficial nodular cystic tumors of the cerebrum attached to the leptomeninx. Histologically, they are pleomorphic, hypercellular glial neoplasms. Despite the presence of microscopic pleomorphism, patients' postoperative prognosis is generally good. Anaplastic PXAs (APXAs) have a high mitotic index and patients with APXAs have a worse prognosis than patients with PXAs. Here, we report an autopsy case of APXA initially diagnosed as PXA. After gross total resection, the tumor recurred and was diagnosed as an APXA; thereafter, the patient died. An autopsy revealed that the tumor had relapsed at the primary site and had spread to the leptomeningeal space while concurrently invading the cerebrum including the periventricular area forming multifocal lesions. The histological findings of the autopsy were similar to those for epithelioid glioblastoma (EGBM) and small cell glioblastoma (SCGBM). In particular, the periventricular area with multifocal lesions was composed of SCGBM-like cells. It has been shown that multifocal lesions are frequently identified in patients with SCGBM. This is the first histopathologically confirmed case of APXA-related tumor presenting with periventricular extension and multifocal lesion formation. The periventricular extension might be a feature of PXAs and APXAs. However, suspected periventricular spread on imaging in past cases of PXAs and APXAs might instead represent the malignant transformation of these tumors to glioblastoma-like high-grade tumors, which often show SCGBM-like histological patterns.

[A 36-year-old woman with primary central nervous system lymphoma diagnosed by twice brain biopsies, showing relapsing and remitting brain lesions].

A 36-year-old woman visited a local hospital suffering from acute onset dizziness. Brain MRI revealed multiple white matter lesions without gadolinium enhancement in the both hemispheres. Although she began to receive a treatment under a clinical diagnosis of multiple sclerosis, she developed newly emerging brain lesions and was referred to our hospital. Neurological examination detected intention tremor, right-sided dysdiadochokinesis, and gait ataxia. Both blood and cerebrospinal fluid tests were unremarkable but follow-up brain MRIs showed rapidly relapsing and remitting lesions. The first brain biopsy ended up showing non-specific changes but the second biopsy with five months interval confirmed primary central nervous system lymphoma (PCNSL). The patient was treated by chemotherapy and showed partial response. It is important to consider sequential brain biopsies if needed because PCNSL may present diverse brain lesions on MRI including non-neoplastic early lesions.

An infant case of diffuse cerebrospinal lesions and cardiomyopathy caused by a BOLA3 mutation.

INTRODUCTION: Mitochondrial dysfunction results in a wide range of organ disorders through diverse genetic abnormalities. We herein present the detailed clinical course of an infant admitted for extensive, rapidly progressing white matter lesions and hypertrophic cardiomyopathy due to a BOLA3 gene mutation. CASE: A 6-month-old girl with no remarkable family or past medical history until 1 month prior presented with developmental regression and feeding impairment. Ultrasound cardiography and brain magnetic resonance imaging (MRI) respectively disclosed the presence of hypertrophic cardiomyopathy and symmetrical deep white matter lesions. She was transferred to our hospital at age 6 months. High lactate levels in her cerebrospinal fluid suggested mitochondrial dysfunction. Despite vitamin supplementation therapy followed by a ketogenic diet, the patient began exhibiting clusters of myoclonic seizures and respiratory failure. Brain and spinal cord MRI revealed rapid progression of the white matter lesions. She died at 10 months of age. Fibroblasts obtained pre-mortem displayed low mitochondrial respiratory chain complex I and II activity. A homozygous H96R (c. 287 A > G) mutation was identified in the BOLA3 gene. DISCUSSION: No reported case of a homozygous BOLA3 gene mutation has survived past 1 year of life. BOLA3 appears to play a critical role in the electron transport system and production of iron-sulfur clusters that are related to lipid metabolism and enzyme biosynthesis.

Nontraumatic Proximal Ulnar Artery Pseudoaneurysm Mimicking a Soft Tissue Tumor in Image Modality.

Aneurysm of the proximal ulnar artery is extremely rare. Ultrasonography, computed tomography, and magnetic resonance imaging generally provide accurate diagnosis of aneurysm. A 29-year-old woman who had undergone an excision biopsy of a mass in her right arm by an orthopedic surgeon was referred to our department. We resected the mass and interposed it with a reversed great saphenous vein. Histopathological examination suggested that the mass was a pseudoaneurysm consisting of organized thrombi with recanalization. Clinicians should be aware of the possibility of misdiagnosis of soft tissue tumor in cases of pseudoaneurysm, especially if imaging examination reveals a density consistent with organized thrombus with recanalization.

Intraoperative detection of inferior vena caval tumor thrombus extending from metastatic lymph node of renal cell carcinoma using ultrasonography.

A 67-year-old man consulted our department with gross hematuria. Computed tomography (CT) revealed a huge renal tumor with a paracaval metastatic lymph node (mLN). Right total nephrectomy was planned for the renal tumor diagnosed as renal cell carcinoma preoperatively. Just before the resection of the renal vein and artery, intraoperative ultrasonography revealed an inferior vena caval tumor thrombus (IVCTT) extending from the mLN. Ultrasonography clearly and dynamically demonstrated a rhythmic flapping movement of the IVCTT with blood flow in the inferior vena cava. Following right radical nephrectomy, IVCTT resection with the vessel wall was performed to reduce the risk of pulmonary tumor thrombus. Histopathological diagnosis of the renal tumor was clear cell renal cell carcinoma, and the resected IVCTT was confirmed histopathologically as tumor involvement from the mLN of the renal cell carcinoma. Intraoperative ultrasonography can detect IVCTT extending from the mLN, whereas CT cannot.

The Complete Remission of Acquired Immunodeficiency Syndrome-associated Isolated Central Nervous System Lymphomatoid Granulomatosis: A Case Report and Review of the Literature.

A 49-year-old man presented with gradually progressive aphasia one month after being diagnosed with acquired immunodeficiency syndrome (AIDS). Brain magnetic resonance imaging showed multiple brain lesions with punctate and linear enhancement. A polymerase chain reaction detected Epstein-Barr virus (EBV) in the patient's cerebrospinal fluid. A diagnosis of isolated central nervous system lymphomatoid granulomatosis (CNS-LYG) was made based on the brain biopsy findings. The complete remission of CNS-LYG was achieved by anti-retroviral therapy (ART) alone. In the present case, the development of AIDS-associated CNS-LYG was considered to have been initiated by the reactivation of EBV in the CNS under immunosuppressive conditions. The patient's condition improved with the reconstitution of the patient's immune system.

Development of combined thymic carcinoma and thymoma in an extrathymic lesion during long follow-up for recurrent thymoma.

The present study reported a rare case of combined thymic squamous cell carcinoma and thymoma exhibiting a mass on the left chest wall. The patient underwent thoracotomy for invasive thymoma 15 years previously, however, suffered a relapse in the left intrathoracic space. Radiotherapy, chemotherapy and partial resection, as secondary surgery for the intrathoracic mass, were performed. The histological findings in the resected specimens revealed type B3 thymoma. As the patient developed a left chest wall mass and pain in 2013, the mass was resected. The histological findings indicated two separate components composed of type B3 thymoma and squamous cell carcinoma. Immunohistological findings revealed that the thymoma cells were positive for CD5, while the thymic carcinoma cells were negative for CD5. Several reports have demonstrated the coexistence of thymic carcinoma and thymoma in the primary thymus, however, the development of a combined tumor in an extrathymic lesion is extremely rare. The present case had a long follow-up for recurrent thymoma. The present case indicated that the development and/or coexistence of malignant components in the thymoma must be taken into consideration for the treatment and/or management of patients with thymoma and that a pre-existence of CD5 expression in thymoma and the lost change may be associated with the process of malignant transformation.

A case of MUC5AC-positive intraductal neoplasm of the pancreas classified as an intraductal tubulopapillary neoplasm?

This report describes a unique case of intraductal tubulopapillary neoplasm (ITPN) of the pancreas in order to clarify its oncogenesis and more precisely classify pancreatic intraductal neoplasms. A 74-year-old man visited our institution for follow-up of acute pancreatitis. Imaging examinations revealed a hypovascular intraductal mass in the head of the pancreas with progressive dilation of the pancreatic duct, atrophy of the pancreatic parenchyma, and a non-mucinous appearance. A pancreatoduodenectomy was performed to identify this pancreatic intraductal neoplasm. Macroscopically, the tumor was a solid nodular mass with no visibly secreted mucin obstructing the dilated ducts. Histologically, it had a homogeneous appearance with nodules of back-to-back tubular glands and occasional papillary elements, and there were no apparent transitions to areas with less marked cytoarchitectural atypia. Although the intraductal neoplastic growth corresponded to an ITPN, immunohistochemical staining revealed partial positivity for MUC5AC, for which ITPNs are characteristically negative. Somatic mutations in KRAS, GNAS, BRAF, and PIK3CA were not detected. A loss of MUC5AC expression and mutations in KRAS and GNAS are key elements in the diagnosis of ITPN. Thus, it was difficult to distinguish the present case as a pancreatobiliary-type (PB-type) intraductal papillary mucinous neoplasm (IPMN) or a phenotypic variant of ITPN. As it is possible that some cases of PB-type IPMN and ITPN overlap, the precise classification of these rare lesions may require re-evaluation.

Late-onset rejection of a unilateral donor lung with vascular C4d deposition in bilateral living-donor lobar lung transplantation: an autopsy case report.

A 37-year-old woman had undergone bilateral living-donor lobar lung transplantation 11 years previously for idiopathic pulmonary arterial hypertension. Her father donated the right lobe and her brother donated the left lobe. She subsequently developed progressively worsening respiratory dysfunction due to pneumonia. CT showed left dominant pulmonary artery dilatation, bronchial wall thickening and airway stenosis, followed by sudden death. An autopsy showed marked pathologic left dominant rejection of the pulmonary artery, small airway and large airway. Notably, only the left lung showed C4d vascular deposition, thus suggesting that antibody-mediated lung rejection may have occurred.