Characterizing Indeterminate Renal Masses with Molecular Imaging: the Role of 99mTc-MIBI SPECT/CT.

PURPOSE OF REVIEW: The majority of enhancing renal masses cannot be characterized through imaging as malignant or benign; however, such characterization could save patients from unnecessary surgery and/or biopsy and associated morbidity. Herein, we review the recent literature on the emerging use of 99mTc-MIBI SPECT/CT in preoperative differentiation of enhancing renal masses. RECENT FINDINGS: Recent reports have shown that 99mTc-MIBI SPECT/CT imaging can differentiate mitochondrial-rich, benign, or indolent renal masses from renal cell carcinoma. These studies demonstrate good correlation between a positive 99mTc-MIBI SPECT/CT scan and a pathologically proven diagnosis of renal oncocytoma and hybrid oncocytic/chromophobe tumor. In addition, there is excellent correlation between a negative scan and a diagnosis of clear cell subtype of renal cell carcinoma. Preoperative 99mTc-MIBI SPECT/CT offers a non-invasive method for differentiating renal lesions with low aggressiveness from other RCCs, in particular, clear cell renal cell carcinoma.

Gonadotrofinomas: análisis multicéntrico y retrospectivo de 66 pacientes / Gonadotrophinomas: multicenter and retrospective analysis of 66 patients

Objetivo: Analizar la presentación clínica, radiológica, bioquímica y el comportamiento posquirúrgico de una cohorte de pacientes portadores de gonadotrofinomas. Pacientes y Métodos: Se evaluaron pacientes con gonadotrofinomas estudiados en nueve centros endocrinológicos de la ciudad de Bs.As. durante el período 1983 a 2003. El criterio de inclusión fue la inmunohistoquímica (IH) positiva para hormona luteinizante (LH), folículoestimulante (FSH) y/o alfa subunidad (ASU). Los adenomas plurihormonales fueron excluidos. Resultados: Fueron analizados 66 pacientes de 51,8 ± 12,1 (X +/- DS) años (39 varones). Los síntomas mas frecuentemente observados fueron las alteraciones visuales (72,8%), seguidas por el hipogonadismo y las cefaleas. El 10,6% se diagnosticaron en forma incidental. El 98,5% fueron macroadenomas, 56,9% de los cuales correspondieron a un estadio Hardy (EH) 3 y 29,6% a un EH 4. El tiempo de seguimiento fue de 47,8 meses (r: 5-168). El hipogonadismo definido bioquímicamente se presentó en el 82,4% de los pacientes. En su mayoría presentaban niveles bajos o inapropiadamente normales de gonadotrofinas, pero 4 mujeres y 3 varones presentaron niveles séricos elevados y disociados de FSH y LH. La hiperprolactinemia por desconexión fue observada en 45,2% de la población (X: 65.6 ng/ml r: 30-172). El hipopituitarismo se detectó en 25,7% de los casos. La cirugía fue transeptoesfenoidal (TSE) en 80%; una segunda operación fue realizada en el 28% de la población. La IH fue positiva por orden de frecuencia para LH, FSH y ASU o las 3 combinaciones. La evolución posquirúrgica evidenció mejoría en el campo visual (CV) en el 41%. La presencia de restos tumorales y/o recidiva fue del 84%. Se indicó radioterapia en 37% y la sustitución hormonal fue necesaria en el 65% de los pacientes.

The aim of our study was to describe the clinical-biochemical and radiologic presentation and the post surgery outcome in a cohort of patients with gonadotrophinomas. Patients were selected from nine Endocrinology Units of the city of Buenos Aires from 1983 at 2003. The inclusion criteria was defined by nonfunctinoning pituitary adenomas with positive innmunohistochemical (IH) for luteinizing hormone (LH), follicle-stimulating hormone (FSH) and/or alpha subunit (ASU). Innmunohistochemically plurihormonal adenomas were excluded. Sixty six patients were analyzed, aged 51,8 ± 12,1 (X +/- DS) years; (39 men). More prevalent symptoms were visual alterations (72,8%), hypogonadism and headaches. Eleven percent was diagnosed as incidentalomas. Ninety eight percent were macroadenomas, 56,9% was Hardy stage (HS) 3 and 29,6% was HS 4. The patients were followed up for 47,8 months (r: 5-168). Hypogonadism was biochemically found in 82,4%. The majority showed low or inappropriately normal levels of gonadotrophins except for 4 women and 3 men that had high and dissociated levels. Hyperprolactinemia was observed in 45,2% and was interpreted as an interference with normal dopamine inhibition of prolactin secretion (X+/-DS: 65.6+/- ng/ml, r: 30-172). Hypopituitarism was found in 25,7% of the patients. Transsphenoidal surgery was carried out in 80% and in 28% a second surgery was needed. The IH was positive for LH, FSH and ASU in this order of frequency or its combinations. Tumor persistency and/or recurrency were found in 84% of the patients. Forty one percent showed improvement of visual defects. Radiotherapy was indicated in 37% and hormonal replacement was needed in 65% of the patients.

Contemporary radiologic imaging of renal cortical tumors.

Contemporary radiologic imaging has resulted in an increasing number of smaller renal cortical tumors being identified. The ability of imaging to classify these tumors is limited, although certain features may help classify the renal cortical neoplasm. The important role of radiologic imaging in tumor detection, characterization, staging, and follow-up of patients who have renal cortical tumors is reviewed in this article.

[Preliminary clinical application of 99Tcm-HYNIC-TOC imaging in somatostatin receptor-positive tumors].

OBJECTIVE: To evaluate the effect of 99Tcm-HYNIC-TOC imaging in localization of somatostatin receptor-positive tumors. METHODS: Forty-four patients were involved in this study, including 22 neuroendocrine tumors, 10 non-neuroendrocrine tumors and 12 benign diseases. All patients were confirmed by histopathologic diagnosis, and had clinical laboratory data, or 1-2 other imaging procedures. Regional, whole body and SPECT/CT (in positive cases) imagings were acquired at 1 and 4 hours after an intravenous injection of 370 MBq 99Tcm-HYNIC-TOC. 99Tcm-HYNIC-TOC imaging was compared with 111In-petetreotide imaging in 4 cases, and with 131I-MIBG imaging in 10 cases. 99Tcm-HYNIC-TOC imaging was performed before and after treatment in 1 non-Hodgkins lymphoma (NHL) patient. RESULTS: The positive imagings were observed in 19 of 32 cases. The sensitivity, specificity, and accuracy of 99Tcm-HYNIC-TOC imaging for somatostatin receptor-positive tumors are 82.6%, 100%, and 87.5%, respectively. The distribution in vivo of 99Tcm-HYNIC-TOC is similar to that of 111In-petetreotide, and showed high physiological uptake in liver, spleen, and kidneys. 99Tcm-HYNIC-TOC imaging demonstrated intense tumor sites uptake at 1 hour after injection, and revealed the lesions first in 6 patients among the imaging modalities, and more lesions that had not been revealed by 131I-MIBG imaging. Compared with imaging before treatment, 99Tcm-HYNIC-TOC imaging confirmed the tumor regression after treatment in 1NHL. CONCLUSIONS: 99Tcm-HYNIC-TOC is promising for the diagnosis and localization of somatostatin receptor-positive tumors.

Scintigraphic assessment of pituitary adenomas and several diseases by indium-111-pentetreotide.

The aim of this study was to identify the specific somatostatin receptors expressed by several tumors, utilizing 111In-octreotide, a long acting somatostatin analogue. We studied two different groups of patients: the first group was composed of 21 patients suffering from different pituitary adenomas, while the second group consisted of 12 patients affected by several different neoplasms. In vivo scintigraphy showed pentetreotide receptors only in large GH-secreting adenomas and several macroadenomas. Concerning the endocrine activity of the adenomas, 111In-octreotide showed a good sensibility in detecting GH-secreting tumors. In the second group, 111In-octeotride proved to be a good diagnostic tool to show carcinoid lesions which were missed by other complementary methodologies.

Moyamoya disease associated with pituitary adenoma--report of two cases.

Moyamoya disease associated with prolactin (PRL)-producing pituitary adenomas occurred in two females with elevated blood PRL levels (285 and 120 ng/ml). Computed tomography revealed cystic tumors extending from the sella turcica to the suprasellar cistern. Carotid angiography demonstrated stenoses or obstructions of the bilateral internal carotid arteries at their end point and development of bilateral basal moyamoya vessels. Histological diagnosis in one case was PRL-producing chromophobe adenoma. No stigmata of neurofibromatosis or any history of irradiation was found. Compression of carotid arteries by the tumor was unlikely. These cases should therefore be classified as moyamoya disease accompanied by brain tumor, a very rare occurrence. The hypothalamic disturbance caused by moyamoya disease may have induced the hyperprolactinemia, resulting in secondary prolactinoma.

Nelson's syndrome following partial pituitary microadenomectomy and pregnancy.

We report for the first time the development of Nelson's syndrome in a patient who had previously undergone unsuccessful pituitary microadenomectomy and subsequently bilateral adrenalectomy. The removal of a 3-mm portion of a microadenoma did not protect against the development of Nelson's syndrome within 3 years which was closely related to pregnancy, a previously noted association. This report suggests that the development of Nelson's syndrome depends not on the size of the initial pituitary tumour but rather on its individual potential for proliferating once free of the inhibitory effects of glucocorticoid excess.

[Persistent trigeminal artery associated with pituitary adenoma]. / Hypophysis adenomával társult persistáló intrasellaris arteria trigemini primitiva.

The authors report of a case with a pituitary macroadenoma which was associated with a persistent trigeminal artery. The tumour was removed by transsphenoidal microsurgical approach to the sella turcica. To recognise the developmental anomaly is very important to avoid complications during operation.

Computed tomography of the brain in patients with serum prolactin levels over 200 ng/ml.

We reviewed the computed tomographic (CT) findings of the sella turcica in 26 patients with a serum prolactin level of over 200 ng/ml. The interval between the dates of CT examination and checking of the serum prolactin level were within 2 months. There were 24 nonpregnant women with a mean age of 30 years and 2 men with a mean age of 28.5 years. None of them were taking medication known to cause an elevation in serum prolactin levels. Surgery was performed on 8 patients with chromophobe adenomas of the pituitary gland: 6 of them were proven to have prolactin-secreting tumors (prolactinomas) after performing a special stain, and the remaining 2 patients, clinically diagnosed as prolactinomas, showed extremely high serum prolactin levels (3,200 and 2,251 ng/ml, respectively). CT studies showed that the height of the pituitary gland in the coronal sections were more than 7 mm in 15 cases (58%) and more than 10 mm in 13 cases (50%); focal bulging of the diaphragma sellae in 16 cases (62%); erosion of the sellar floor in 20 cases (77%); deviation of the pituitary stalk in 19 cases (73%); and abnormal attenuation or enhancement of the pituitary gland in 18 cases (69%). Three patients (12%) showed no evidence of any abnormal CT finding despite a hyperprolactinemic state of over 200 ng/ml. Six histologically proven cases (23%) of prolactinomas and chromophobe adenomas showed radiologic evidence of cavernous sinus invasion. We conclude that patients with a serum prolactin level higher than 200 ng/ml generally show significant changes in the sella turcica in CT.

Neurological visual fields.

Neurological visual field defects represent lesions to the visual pathway, some of which may be life-threatening. It is, therefore, crucial that optometrists understand how to diagnose these lesions, so they may know when, and to whom to refer the patient. The following cases illustrate the management of patients with lesions to the prechiasmal, chiasmal, and postchiasmal visual pathway.

Dynamic CT scan of intracranial tumors.

Of ninety-eight patients with intracranial tumors examined by dynamic CT scanning, 66 were confirmed operatively and pathologically. Our study showed that: 1) Dynamic CT can be performed safely and easily in outpatients; 2) Acoustic neurinoma, meningioma, pituitary chromophobe adenoma, astrocytoma and metastatic tumor have varying levels of time-density curves; 3) The tissue-blood ratio (TBR) at peak time (TBRp) is a useful indicator of the vascularity of tumoral tissues, and analysis of the time-density curve combining with TBRp is helpful to the differential diagnosis of tumors; 4) Differential diagnosis between tumors and vascular abnormalities such as aneurysm and arteriovenous malformation could be made easily with dynamic CT.

[A case of pituitary adenoma presenting binasal inferior quadrants hemianopsia].

Visual field defect due to pituitary adenoma ordinarily shows bitemporal hemianopsia. But we experienced a case presenting binasal inferior quadrants hemianopsia. A 60-year-old woman was admitted to our hospital complaining of headache and blurred vision. At ophthalmologic examination, the visual acuity on the right was 0.02 and on the left 0.3. Visual field showed a loss of bilateral inferior nasal quadrants. There was neither pallor nor edema of either of the optic disks. A computerized tomography (CT) scan showed an enhancing mass in the intra- and suprasellar region. But despite remarkable suprasellar expansion of the tumor, the straight view of bilateral carotid angiograms revealed no elevation of the first part of the anterior cerebral arteries (ACA). On the lateral view, the terminal portion of the precommunicating part of the left ACA showed rather marked anteroinferior displacement. 2 mm thin sliced CT scans at the suprasellar region revealed that the left internal carotid artery had been touching the lateral portion of the tumor and the ACA had been displaced anteriorly by the tumor. Two weeks after admission, transsphenoidal tumor resection was carried out. Total removal was achieved and histological examination showed that the tumor was nonfunctioning chromophobe adenoma. The postoperative course was uneventful except for transient diabetes insipidus. The patient's visual acuity rapidly improved to 0.8 on the right and 0.5 on the left two weeks after operation. Although there was still a tendency for left inferior nasal field defect, remarkable improvement was obtained subjectively and objectively. According to the findings of CT scans and cerebral angiograms, binasal hemianopsia may have been produced by the mechanism as follows.(ABSTRACT TRUNCATED AT 250 WORDS)

Invasive pituitary adenoma presenting with nasal obstruction.

We report two cases of massive invasive pituitary adenoma with the unusual presentation of nasal obstruction. In both cases the diagnosis was only made when the obstructing tissue was removed. Cases reported previously have usually presented with severe focal neurological signs or a long history of neurological symptoms. These two cases are unusual in having minimal neurological deficits despite the extension of tumour into the nasopharynx and the middle and posterior cranial fossae. These extensions were well illustrated by computerised tomography. This unusual presentation is discussed with reference to the literature.

Third nerve palsy: the presenting sign of a pituitary adenoma in five patients and the only neurological sign in four patients.

Five male patients sought medical attention for diplopia and were found to have third nerve palsies secondary to pituitary adenomas. In four cases this was the only neurologic abnormality. In the fifth there was an additional, asymptomatic, temporal visual field defect in one eye. Partial third nerve involvement was seen in all but one patient. Four patients underwent successful surgery and were found to have chromophobe adenomas. One patient had clinical and laboratory evidence of Cushing's syndrome. An initial diagnosis of cerebral aneurysm was made in three cases when the third nerve palsy followed a severe, acute headache. Later it became evident that pituitary apoplexy was the correct diagnosis. The mechanisms by which a pituitary adenoma causes a third nerve palsy are discussed. The importance of recognizing a pituitary tumor as the etiology of an isolated third nerve palsy is emphasized.

Pituitary tumour causing multiple endocrinopathies in a dog.

A 9-year-old male Boxer with signs of lethargy, weight gain, polyuria, polydipsia, eosinopaenia and lymphopaenia was diagnosed as having hyperadrenocorticism. Concurrent central diabetes insipidus was diagnosed using a water deprivation test and antidiuretic hormone response test. A contrast radiographic technique was used to outline a pituitary mass. A chromophobe adenoma and secondary hypothyroidism were found on post-mortem examination.

'Normal' and 'abnormal' crossed asymmetry in monocular visual evoked potentials.

To restate the above, in the population of 29 normal subjects tested by us, 'normal' crossed asymmetry occurred in one-fifth on the FVEP study and in none on the PSVEP study; this 'normal' crossed asymmetry was always undirectional, larger Wave III being contralateral to the stimulated eye. Deviations from these observations, namely a larger Wave III ipsilateral to the stimulated eye, or a crossed asymmetry of P100 on the PSVEP study are probably examples of 'abnormal' crossed asymmetries. However, a 'normal' crossed asymmetry may occur in some abnormal situations as well, e.g. diseases and syndromes with optic misrouting as noted earlier.