Itaru Tsumanuma

Clinicopathological study of pineal parenchymal tumors: correlation between histopathological features, proliferative potential, and prognosis

This study describes the clinicopathologic features of 13 cases with pineal parenchymal tumors. Based on the histopathologic findings, especially the extent of atypia and pineocytic differentiation as determined by Bodians staining, we classified these tumors into pineocytomas (4), pineocytomas with anaplasia (4) and pineoblastomas (5). All the cases with pineocytoma and pineocytoma with anaplasia were adults, and all the cases with pineoblastoma were younger children. One patient with pineocytoma died of other disease 7 months after initial treatment. One patient with pineocytoma with anaplasia died 168 months after initial treatment. The other patients with pineocytoma and pineocytoma with anaplasia survived between 9 and 179 months after surgery. However, all of the five pineoblastoma patients died within 14 months after initial treatment. The mean MIB-1 index in pineoblastomas was significantly higher than that in other types of pineal parenchymal tumors, but there were no differences between pineocytomas and pineocytomas with anaplasia with respect to the MIB-1 index. The mean MIB-1 index in neurofilament protein-immunopositive cases was significantly lower than that in immunonegative cases. With regard to the malignant potential, we emphasize that a clear distinction should be made between pineoblastomas in children and other types of pineal parenchymal tumors in adults.

Preoperative depiction of cavernous sinus invasion by pituitary macroadenoma using three-dimensional anisotropy contrast periodically rotated overlapping parallel lines with enhanced reconstruction imaging on a 3-tesla system.

OBJECTIVES Three-dimensional anisotropy contrast (3DAC) magnetic resonance (MR) imaging provides clear depiction of neuronal fibers. The aim of this study was to identify intracavernous cranial nerves in patients with pituitary macro-adenoma and in healthy volunteers by using 3DAC MR imaging on a 3-tesla system and to preoperatively predict cavernous sinus invasion by pituitary macroadenoma. METHODS Thirty-three patients (cavernous sinuses in 66 sides) with pituitary macroadenomas and 25 healthy volunteers (50 sides) participated in this study. Coronal 3DAC MR images constructed from diffusion weighted images, acquired with periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) sequences, and T2-weighted reverse images were obtained at the same anatomical locations using a 3-tesla MR imaging system. Attempts were made to identify the cranial nerves. RESULTS The oculomotor and ophthalmic/maxillary nerves were preoperatively identified in all sides (66 sides in patients and 50 sides in healthy volunteers) on 3DAC MR images. In the 33 patients, cavernous sinus invasion was revealed in 10 (12 [18.2%] of 66 sides) by intraoperative endoscopic observation. Coronal 3DAC MR images revealed that the oculomotor nerves were half surrounded with adenoma in all 12 of these sides, and the ophthalmic/maxillary nerves were half encapsulated with tumor (sensitivity/specificity: 100%/100% and 83%/100%, respectively). CONCLUSIONS Preoperative evaluation of pituitary macroadenomas using 3DAC PROPELLER MR imaging on a 3-tesla system is likely to be a powerful noninvasive method of detecting cavernous sinus invasion, which can potentially dominate the therapeutic strategy for these lesions.

Demonstration of hydroxyindole‐O‐methyltransferase (HIOMT) mRNA expression in pineal parenchymal tumors: Histochemical in situ hybridization

The expression of hydroxyindole‐O‐methyltransferase (HIOMT), an enzyme catalyzing the final step of melatonin biosynthesis, was examined in three pineoblastomas and five pineocytomas by in situ hybridization analysis. Distinct hybridization signals for HIOMT mRNA, though weaker than in normal pineal gland pinealocytes, were detected in two of the three pineoblastoma and three of the five pineocytoma cases. Of the pineoblastomas, hybridization signals were observed in most tumor cells of one case, while in another, signals were detected in occasional cells clustered or scattered throughout the neoplastic field. Of the pineocytomas, signals were detected in most tumor cells of two cases, while in one case, signals were detected only in occasional cells. Among these specimens, one pineoblastoma and one pineocytoma were also analyzed using northern blot and reverse transcription polymerase chain reaction (RT‐PCR) analyses. In the northern blot analysis, an apparently single band corresponding to the size of HIOMT mRNA was detected in both pineoblastoma and pineocytoma RNA blots. In the RT‐PCR analysis, three species of HIOMT mRNA generated via alternative splicing were detected in both tumors. These results suggest that the neoplastic cells of pineoblastomas and pineocytomas often retain the ability to express HIOMT mRNA, as in normal pinealocytes, and that HIOMT is a useful tumor marker for the diagnosis of pineal parenchymal tumors.

Synchronized multiple regression of diagnostic radiation-induced rather than spontaneous: disseminated primary intracranial germinoma in a woman: a case report.

IntroductionExamples of the spontaneous regression of primary intracranial germinomas can be found in the literature. We present the case of a patient with disseminated lesions of primary intracranial germinoma which synchronously shrunk following diagnostic irradiation. We will discuss whether this regression was spontaneous or radiation-induced.Case presentationA 43-year-old Japanese woman presented to our hospital complaining of memory problems over a period of one year and blurred vision over a period of three months. Following magnetic resonance imaging, she was found to have a massive lesion in the third ventricle and small lesions in the pineal region, fourth ventricle, and in the anterior horn of the left lateral ventricle. Prior to an open biopsy to confirm the pathology of the lesions, she underwent a single cranial computed tomography scan and a single cranial digital subtraction angiography for a transcranial biopsy. Fourteen days after the first magnetic resonance image - 12 and eight days after the computed tomography scan and digital subtraction angiography, respectively - a pre-operative magnetic resonance image was taken, which showed a notable synchronous shrinkage of the third ventricle tumor, as well as shrinkage of the lesions in the pineal region and in the fourth ventricle. She did not undergo steroid administration until after a biopsy that confirmed the pathological diagnosis of pure germinoma. She then underwent whole craniospinal irradiation and went into a complete remission.ConclusionsIn our case report, we state that diagnostic radiation can induce the regression of germinomas; this is the most reasonable explanation for the synchronous multiple regression observed in this case of germinoma. Clinicians should keep this non-spontaneous regression in mind and monitor germinoma lesions with minimal exposure to diagnostic radiation before diagnostic confirmation, and also before radiation treatment with or without chemotherapy begins.

Occipital Transtentorial Approach and Combined Treatments for Pineal Parenchymal Tumors

The deep-seated location of pineal parenchymal tumors (PPTs) and their associations with critical structures make their surgical resection technically challenging; further, the rarity of PPTs and repeated changes in their histopathological diagnostic criteria makes the study of their biological behavior and clinical outcomes difficult. Here, we describe the surgical techniques and results of an occipital transtentorial approach for PPTs together with the results in the clinicopathological study of PPTs. Since 1982, we have treated 93 patients with pineal region tumors, including 17 PPTs, with the occipital transtentorial approach using the lateral semiprone position. The infrasplenial approach is helpful in separating the internal cerebral veins from the tumor, particularly when the tumor is tightly adherent to the veins. Permanent homonymous hemianopsia occurred in 1 of the 17 patients with PPTs. Permanent ocular movement disorders were not encountered. Extensive removal of the tumor significantly prolongs survival at least in patients with pineocytomas and PPT of intermediate differentiation (PPTIMD). Despite extensive resection and adjuvant radiochemotherapy, the prognosis of the patients with pineoblastomas is extremely poor. Although the proliferative potentials of pineocytomas and PPTIMD were significantly lower than those of pineoblastomas, there was no such difference between pineocytomas and PPTIMD.

Establishment of two glioma cell lines from two surgical specimens obtained at different times from the same individual

We established two glioma cell lines from two surgical specimens obtained at different times from the same patient. One (No. 9R), which was derived from the recurrent tumor (glioblastoma, grade IV), proliferated more rapidly in vitro than the other (No. 9) from the primary tumor (slightly anaplastic astrocytoma, grade II–III). No. 9R showed heterotransplantability in nude mice, whereas No. 9 did not. These findings indicate that No. 9R has a more aggressive or malignant nature than No. 9. Both cell lines showed homozygous deletion of the representative tumor suppressor p16 and p15 genes, but no p53 gene alteration. However, examination of the overall mRNA expression profile using a commercially available cDNA-spotted membrane revealed much higher expression levels of several mRNAs, at least, in No. 9R than in No. 9, although the relationship between these mRNAs and the growth potentials remained unknown. These two cell lines, derived from the same individual, with different proliferating potentials may be useful for studies on the molecular bases of glioma malignancy and progression.

Pituitary Adenoma Manifesting as an Isolated Abducens Palsy

Ocular motor nerve palsies are rare complications of pituitary adenoma. We treated a patient who presented with an isolated abducens palsy and was subsequently found to have a pituitary adenoma. A 62-year-old woman was referred to us for an evaluation of her diplopia. She had an esotropia, which was larger on right gaze, and a limited abduction OD. Visual fields were normal. CT and MRI revealed a sellar region tumor invading the right cavernous sinus without compressing the optic chiasm. A diagnosis of macroprolactinoma was made endocrinologically. Her diplopia and right abducens palsy were quickly resolved and MRI showed significant shrinkage of the tumor after she was treated with cabergoline. A sixth nerve palsy can be the sole presenting feature of pituitary adenoma and can be treated effectively with medication.

Basal ganglion hamartoma in a patient presenting with precocious puberty.

We report a basal ganglion hamartoma in a 10-year-old boy in whom the major clinical feature was precocious puberty. Endocrinological evaluation showed a gonadotropin reaction to luteinizing hormone-releasing hormone with no elevation of the human chorionic gonadotropin β-subunit level in the serum or cerebrospinal fluid. Neuroimaging studies showed a small, calcified, nonenhanced mass lesion with some cystic components in the right basal ganglion. Histopathological examination of specimens removed by stereotactic needle biopsy revealed disorganized neuronal and glial elements in the calcified gray matter-like lesion. In addition, although the presence of microcalcifications was not conspicuous, similar neuroglial lesions of various sizes were scattered in the surrounding white matter. Immunostaining for Ki-67 antigen (MIB-1) showed very low proliferative potential of the glial cells in all the lesions. To our knowledge, this is the first reported occurrence of an intracranial hamartoma located in a site other than the hypothalamus and causing precocious puberty. The possible mechanisms underlying the development of precocious puberty in this patient are discussed.