Mineko Murakami

A mechanism of acquiring temozolomide resistance during transformation of atypical prolactinoma into prolactin-producing pituitary carcinoma: case report.

BACKGROUND AND IMPORTANCE:The case presented here describes the clinical evolution of a pituitary carcinoma from an atypical prolactinoma after temozolomide (TMZ) treatment. The mechanism of acquisition of TMZ resistance was analyzed. CLINICAL PRESENTATION:A 60-year-old woman with atypical prolactinoma had been treated for 7 years with multiple therapies, including dopamine agonists, surgical intervention (5 times), conventional radiotherapy, and radiosurgery. The patient deteriorated as a result of tumor enlargement. Ten cycles of TMZ therapy, 200 mg/m2 for 5 days every 4 weeks, improved the patients performance status and caused tumor shrinkage. Six months after discontinuation of TMZ, the tumor progressed into pituitary carcinoma with tumor regrowth and intraventricular dissemination. TMZ therapy was ineffective this time. A sixth surgery and salvage chemotherapy failed to improve the patients condition, and she died 9 years after the first diagnosis. Throughout the treatment course, O6-methyl-guanine-DNA methyltransferase (MGMT) was immunonegative in the tumor specimens, including the TMZ-refractory pituitary carcinoma. Mutation of p53 was identified in both the atypical prolactinoma and pituitary carcinoma. In contrast, major differences were noted for mismatch repair protein MSH6 immunostaining: Although MSH6 was diffusely immunopositive in the atypical adenoma, it became immunonegative when the tumor evolved into TMZ-refractory pituitary carcinoma. CONCLUSION:Loss of MSH6 occurred during the progression from an atypical prolactinoma to a pituitary carcinoma, which may have caused resistance to TMZ treatment. This case suggests that preserving MSH6 function is essential for responsiveness to TMZ treatment in MGMT-negative and p53-mutated atypical pituitary adenoma or pituitary carcinoma.

A case of multiple brain metastases of uterine leiomyosarcoma with a literature review

Brain metastasis from uterine leiomyosarcoma is extremely rare, and prognostically alarming despite various treatments. The authors report a case of multiple brain metastases from uterine leiomyosarcoma who took a favorable course after tumor resection and γ-knife treatment. A 50-year-old woman with a history of hysterectomy for uterine leiomyosarcoma two years earlier, presented with a recent onset of headaches and vomiting. Multiple cerebral lesions were found by magnetic resonance imaging (MRI). The Karnofsky performance scale (KPS) was 40 with left hemiparesis and cerebellar ataxia. She was treated by resection of the left occipital and cerebellar tumors, followed by γ-knife irradiation of the residual tumors. KPS was 70 at her discharge from the hospital. MRI failed to show recurrence of the intracranial lesions 6 months after irradiation. She remained at home until she died from massive intra-abdominal bleeding. This is the first case with multiple brain metastases from uterine leiomyosarcoma, who survived with remarkable neurological improvement for 12 months. No comparable survival has been reported in the literature. It is evident that surgical resection and additional γ-knife irradiation contributed to early neurological recovery.

A simple and consistent technique for ventricular catheter insertion using a tripod.

OBJECTIVE For long-term preservation of ventriculo-peritoneal (VP) shunt function, it is essential to place the ventricular catheter tip above the foramen of Monro. But the free-hand technique for ventricular catheter passage is not consistent. METHODS Supposing that a convex of skull matches to a sphere, in which the foramen of Monro is the center, a perpendicular direction from the surface of the sphere to inside always directs toward the center. The authors identified the range of skull where corresponded to the sphere by magnetic resonance imaging assessment and utilized tripod to achieve exactly perpendicular insertion of ventricular catheter. And an optimal length of catheter insertion was investigated by navigation system. RESULTS The anterior-posterior range of the spherical portion was from coronal suture to 20mm anterior, and the lateral range of it was between 15 and 35mm lateral from sagittal suture. The optimal catheter length for insertion was between 55 and 58mm from the brain surface. Ideal placement of a ventricular catheter tip was achieved in more than 90% of cases (31/34) with this technique. CONCLUSION Tripod-guided ventricular catheter insertion is a simple and reliable method for VP shunt at any angle of head-rotation.

Microsurgical excision of a retro-odontoid disc hernia via a far-lateral approach : successful treatment of a rare cause of myelopathy : case report

OBJECTIVE AND IMPORTANCEAmong mass lesions causing myelopathy at the craniovertebral junction, retro-odontoid intervertebral disc hernias are very rare, with only four such cases reported in the literature. CLINICAL PRESENTATIONA 77-year-old woman with this rare condition complained of motor and sensory disturbances in her extremities. Magnetic resonance imaging scans demonstrated an extradural mass lesion at the craniovertebral junction, compressing the lower medulla oblongata and the upper cervical cord posteriorly. INTERVENTIONThe lesion, which was partly mucinous cartilaginous and partly fatty and fibrous, was meticulously removed via a left far-lateral approach. The lesion was not neoplastic but was determined to be composed of fibrocartilaginous tissue, consistent with disc material. Postoperatively, the patient’s sensory disturbances and motor weakness improved, and magnetic resonance imaging scans demonstrated marked shrinkage of the lesion. CONCLUSIONSagittal, T1-weighted, magnetic resonance imaging scans demonstrated a low-intensity band between the odontoid process and the body of the axis, which suggested a persistent cartilaginous band. Although upward migration of a herniated disc from the lower cervical spine and degeneration of retro-odontoid ligaments might be possible causes, a persistent cartilaginous band extending between the odontoid process and the body of the axis was considered to be the more likely origin of the retro-odontoid intervertebral disc hernia. Because the far-lateral surgical approach does not require retraction of the cervical cord and provides safe access to the lesion at the craniovertebral junction, it is a suitable surgical method for this condition.

Ischemic symptoms induced by occlusion of the unilateral vertebral artery with head rotation together with contralateral vertebral artery dissection—case report

We report a 45-year-old woman whose unilateral vertebral artery (VA) was potentially occluded with head rotation at the C1-C2 level and her ischemic symptoms suddenly appeared because of contralateral VA dissection. She noticed first pain around the posterior part of her neck on the right side, and then dizziness when turning the head to the right side. The dizziness disappeared immediately after her head returned to the natural position. Digital subtraction angiography (DSA) showed a string sign of the right VA. DSA and computed tomography angiography (CTA) showed high grade extrinsic compression of the left VA at the C1-C2 level with head rotation more than 90 degrees to the right. Three-dimensional (3D) CTA also showed clearly kinking of the left VA at the C2 neuroforamina. Her symptoms disappeared completely with conservative therapy, and recanalization of the right VA was also confirmed by 3D-CTA. 3D-CTA was thought to be valuable to diagnose and manage the rotational compression of the artery. VA dissection must be remembered to differentially diagnose the etiology of transient attacks of posterior circulation ischemia due to rotational contralateral VA occlusion.

Tumefactive multiple sclerosis requiring emergent biopsy and histological investigation to confirm the diagnosis: a case report

IntroductionTumefactive multiple sclerosis is a demyelinating disease that demonstrates tumor-like features on magnetic resonance imaging. Although diagnostic challenges without biopsy have been tried by employing radiological studies and cerebrospinal fluid examinations, histological investigation is still necessary for certain diagnosis in some complicated cases.Case presentationA 37-year-old Asian man complaining of mild left leg motor weakness visited our clinic. Magnetic resonance imaging demonstrated high-signal lesions in bilateral occipital forceps majors, the left caudate head, and the left semicentral ovale on fluid-attenuated inversion recovery and T2-weighted imaging, and these lesions were enhanced by gadolinium-dimeglumin. Tumefactive multiple sclerosis was suspected because the enhancement indistinctly extended along the corpus callosum on magnetic resonance imaging and scintigraphy showed a low malignancy of the lesions. But oligoclonal bands were not detected in cerebrospinal fluid. In a few days, his symptoms fulminantly deteriorated with mental confusion and left hemiparesis, and steroid pulse therapy was performed. In spite of the treatment, follow-up magnetic resonance imaging showed enlargement of the lesions. Therefore, emergent biopsy was performed and finally led to the diagnosis of demyelinating disease. The enhanced lesion on magnetic resonance imaging disappeared after one month of prednisolone treatment, but mild disorientation and left hemiparesis remained as sequelae.ConclusionsFulminant aggravation of the disease can cause irreversible neurological deficits. Thus, an early decision to perform a biopsy is necessary for exact diagnosis and appropriate treatment if radiological studies and cerebrospinal fluid examinations cannot rule out the possibility of brain tumors.

Molecular status of pituitary carcinoma and atypical adenoma that contributes the effectiveness of temozolomide

There have been several reports of temozolomide (TMZ) treatment of pituitary carcinomas and atypical adenomas. O6-methyl-guanine-DNA methyltransferase is not the sole molecule determining the sensitivity to TMZ in pituitary carcinomas and atypical adenomas. The Japan Society of Hypothalamic and Pituitary Tumors study suggests that MSH6, one of mismatch repair pathway enzyme, fulfills a contributory role to the efficacy of TMZ treatment for pituitary carcinomas and atypical adenomas. The preserved MSH6 function might be essential for the responsiveness to TMZ treatment in pituitary carcinomas and atypical adenomas.

Co-transfection of EYFP-GH and ECFP-rab3B in an experimental pituitary GH3 cell: a role of rab3B in secretion of GH through porosome

Recently, in order to elucidate the role of rab3B in porosome, we have observed the incorporation of rab3B in the secretion of GH through porosome under confocal laser scanning microscopy (CLSM). Transfected cells with GH-EYFP fusion protein and rab3B-ECFP fusion protein were observed under CLSM, which showed the colocalization of EYFP-GH and ECFP-rab3B in the budding configuration of secretory process. These structural and functional images of rab3B imply the incorporation of rab3B in the secretion of GH through porosome.

Vertebral artery dissection caused by swinging a golf club: case report and literature review.

Vertebral artery (VA) dissection caused by swinging a golf club is extremely rare, and the mechanism of the dissection has not been elucidated. A 39-year-old man suddenly felt sharp neck pain and dizziness when he swung a driver while playing golf and visited our clinic. Imaging studies showed acute right cerebellar infarction and complete occlusion of the right VA at the C2 (axis) level. After 1 month of 100 mg aspirin treatment, the occluded right VA was completely recanalized and the patient became totally asymptomatic. Professional golfers look at the position of the ball on the ground or tee until completion of their follow-through. However, some amateur golfers look in the direction that the ball travels at the beginning of their follow-through. It is hypothesized that this rapid disproportionate head rotation produces VA elongation and distortion, mainly at the C2 level, causing stenosis or occlusion of the artery.

Clinicopathological and molecular histochemical review of skull base metastasis from differentiated thyroid carcinoma.

Skull base metastasis from differentiated thyroid carcinoma including follicular thyroid carcinoma (FTC) and papillary thyroid carcinoma (PTC) is a rare clinical entity. Eighteen FTC cases and 10 PTC cases showing skull base metastasis have been reported. The most common symptom of skull base metastasis from FTC and PTC is cranial nerve dysfunction. Bone destruction and local invasion to the surrounding soft tissues are common on radiological imaging. Skull base metastases can be the initial clinical presentation of FTC and PTC in the presence of silent primary sites. The possibility of skull base metastasis from FTC and PTC should be considered in patients with the clinical symptoms of cranial nerve dysfunction and radiological findings of bone destruction. A variety of genetic alterations in thyroid tumors have been identified to have a fundamental role in their tumorigenesis. Molecular histochemical studies are useful for elucidating the histopathological features of thyroid carcinoma. Recent molecular findings may provide novel molecular-based treatment strategies for thyroid carcinoma.