Pituitary metastasis,a rare kind of intracranial malignant tumor,is characterized by metastasis from all parts of the body to the pituitary.The common tumors metastatic to pituitary are abundant with blood supply,located in the posterior pituitary lobe and/or the pituitary stalk.The lesion shows infiltrative growth,and mainly demonstrates low signal on T1 weighted imaging and high signal on T2 weighted imaging.It is usually enhanced significantly after iodinated contrast administration.The metastatic tumor with poor blood supply is similar to pituitary macroadenoma on magnetic resonance image,which makes it difficult to be differentiated.We reported two cases of pathologically diagnosed pituitary metastasis with poor blood supply and reviewed related papers,aiming to provide the imaging differentiation points of hypovascular pituitary metastasis.
Contrast Media ; Humans ; Magnetic Resonance Imaging ; Pituitary Diseases ; Pituitary Gland ; Pituitary Neoplasms/diagnostic imaging*

With the generalized use of highly sensitive thyroid stimulating hormone (TSH) and free thyroid hormone assays, most thyroid function tests (TFTs) are straightforward to interpret and confirm the clinical impressions of thyroid diseases. However, in some patients, TFT results can be perplexing because the clinical picture is not compatible with the tests or because TSH and free T4 are discordant with each other. Optimizing the interpretation of TFTs requires a complete knowledge of thyroid hormone homeostasis, an understanding of the range of tests available to the clinician, and the ability to interpret biochemical abnormalities in the context of the patient's clinical thyroid status. The common etiologic factors causing puzzling TFT results include intercurrent illness (sick euthyroid syndrome), drugs, alteration in normal physiology (pregnancy), hypothalamic-pituitary diseases, rare genetic disorders, and assay interference. Sick euthyroid syndrome is the most common cause of TFT abnormalities encountered in the hospital. In hypothalamic-pituitary diseases, TSH levels are unreliable. Therefore, it is not uncommon to see marginally high TSH levels in central hypothyroidism. Drugs may be the culprit of TFT abnormalities through various mechanisms. Patients with inappropriate TSH levels need a differential diagnosis between TSH-secreting pituitary adenoma and resistance to thyroid hormone. Sellar magnetic resonance imaging, serum α-subunit levels, serum sex hormone-binding globulin levels, a thyrotropin-releasing hormone stimulation test, trial of somatostatin analogues, and TR-β sequencing are helpful for the diagnosis, but it may be challenging. TFTs should be interpreted based on the clinical context of the patient, not just the numbers and reference ranges of the tests, to avoid various pitfalls of TFTs and unnecessary costly evaluations and therapies.
Diagnosis ; Diagnosis, Differential ; Diagnostic Errors ; Euthyroid Sick Syndromes ; Homeostasis ; Humans ; Hyperthyroidism ; Hypothyroidism ; Magnetic Resonance Imaging ; Physiology ; Pituitary Neoplasms ; Rare Diseases ; Reference Values ; Sex Hormone-Binding Globulin ; Somatostatin ; Thyroid Diseases ; Thyroid Function Tests ; Thyroid Gland ; Thyrotropin ; Thyrotropin-Releasing Hormone

Adenoma ; diagnosis ; surgery ; Aged ; Female ; Humans ; Magnetic Resonance Imaging ; Neoplasm Invasiveness ; Optic Chiasm ; pathology ; Pituitary Neoplasms ; diagnosis ; diagnostic imaging ; surgery ; Recurrence ; Treatment Outcome

The early diagnosis and treatment of pituitary carcinoma is difficult. The diagnosis is often delayed, and the confirmation of a diagnosis requires the presence of distant subarachnoid,brain or systemic metastasis from the primary pituitary tumor in the sella and also needs the evidences of pathology and imaging of the primary pituitary carcinoma and metastases. Treatment of pituitary carcinoma includes surgery, radiation therapy ,hormone therapy, chemotherapy, and molecularly targeted therapy; however, these methods are mainly palliative and can not prolong the survival. The prognosis remains poor. Efforts should be made to develop more effective diagnosis and treatment options.
Diagnostic Imaging ; Humans ; Pituitary Neoplasms ; Prognosis

Adolescent ; Adult ; Female ; Humans ; Magnetic Resonance Imaging ; Male ; Pituitary Neoplasms ; pathology ; Thyroid Dysgenesis ; diagnostic imaging ; pathology

BACKGROUND: Multiple endocrine neoplasia type 1 (MEN1) is a rare inherited disorder characterized by the simultaneous occurrence of endocrine tumors in target tissues (mainly the pituitary, endocrine pancreas, and parathyroid glands). MEN1 is caused by mutations in the MEN1 gene, which functions as a tumor suppressor and consists of one untranslated exon and nine exons encoding the menin protein. This condition is usually suspected when we encounter patients diagnosed with tumors in multiple endocrine organs, as mentioned above. METHODS: A 65-year-old woman who underwent surgery for a pancreatic tumor (serous cystadenoma) 5 years previously was referred to our hospital due to neurologic symptoms of diplopia and left ptosis. Brain magnetic resonance imaging revealed a 3.4-cm lesion originating from the cavernous sinus wall and extending into the sellar region. It was thought to be a nonfunctioning tumor from the results of the combined pituitary function test. Incidentally, we found that she also had a pancreatic tumor, indicating the necessity of genetic analysis for MEN1. RESULTS: Genomic analysis using peripheral leukocytes revealed a heterozygous c.1621G>A mutation in the MEN1 gene that was previously reported to be either a pathogenic mutation or a simple polymorphism. We pursued a stereotactic approach to the pituitary lesion, and microscopic findings of the tumor revealed it to be an intrasellar cavernous hemangioma, a rare finding in the sellar region and even rarer in relation to oculomotor palsy. The patient recovered well from surgery, but refused further evaluation for the pancreatic lesion. CONCLUSION: There is great emphasis placed on genetic testing in the diagnosis of MEN1, but herein we report a case where it did not assist in diagnosis, hence, further discussion on the role of genetic testing in this disease is needed. Also, in cases of pituitary tumor with cranial nerve palsy, despite its low prevalence, intrasellar cavernous hemangioma could be suspected.
Aged ; Brain ; Cavernous Sinus ; Cranial Nerve Diseases ; Diagnosis ; Diagnostic Errors* ; Diplopia ; Exons ; Female ; Genetic Testing ; Hemangioma, Cavernous* ; Humans ; Islets of Langerhans ; Leukocytes ; Magnetic Resonance Imaging ; Multiple Endocrine Neoplasia Type 1* ; Neurologic Manifestations ; Paralysis ; Pituitary Function Tests ; Pituitary Neoplasms ; Prevalence

BACKGROUND/AIMS: Although magnetic resonance imaging (MRI) is a good visual modality for the evaluation of pituitary lesions, it has limited value in the diagnosis of mixed nodules and some cystic lesions. We evaluated the usefulness of 18F-fluorodeoxyglucose positron emission tomography (FDG PET) for patients with pituitary lesions. METHODS: 18F-FDG PET and MRI were performed simultaneously in 32 consecutive patients with pituitary lesions. The relationships between FDG uptake patterns in PET and MRI findings were analyzed. RESULTS: Of 24 patients with piuitary adenomas, 19 (79.2%) showed increased uptake of 18F-FDG in the pituitary gland on PET scans. All patients with pituitary macroadenomas showed increased 18F-FDG uptake on PET scans. Meanwhile, only five (50%) of the 10 patients with pituitary microadenomas showed positive PET scans. Interestingly, of two patients with no abnormal MRI findings, one showed increased 18F-FDG uptake on PET. For positive 18F-FDG uptake, maximum standardized uptake values (SUVmax) > 2.4 had 94.7% sensitivity and 100% specificity. In addition, SUVmax increased in proportion to the size of pituitary adenomas. Most cystic lesions did not show 18F-FDG uptake on PET scans. CONCLUSIONS: About 80% of pituitary adenomas showed positivity on PET scans, and SUVmax was related to the size of the adenomas. PET may be used as an ancillary tool for detection and differentiation of pituitary lesions.
Adenoma/pathology/*radionuclide imaging ; Adolescent ; Adult ; Aged ; Aged, 80 and over ; Female ; Fluorodeoxyglucose F18/*diagnostic use ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Pituitary Gland/pathology/*radionuclide imaging ; Pituitary Neoplasms/pathology/*radionuclide imaging ; *Positron-Emission Tomography ; Predictive Value of Tests ; Radiopharmaceuticals/*diagnostic use ; Tumor Burden ; Young Adult

Multiple endocrine neoplasia type 1 (MEN1) is an inherited autosomal dominant disease presenting with pancreatic neuroendocrine tumors (pNETs), parathyroid tumors, or pituitary tumors. Using the PubMed database, we reviewed the literature on information regarding the proper diagnosis and treatment of MEN1-associated pNET. Many cases of MEN1-associated pNET are functioning pNETs. Gastrinomas and insulinomas tend to occur frequently in the duodenum and pancreas, respectively. In addition to diagnostic imaging, the selective arterial secretagogue injection test (SASI test) is useful for localizing functioning pNET. The standard treatment is surgical resection. However, in the case of a functioning pNET, the tumor should first be accurately located using the SASI test before an appropriate surgical method is selected. In cases of a MEN1-associated non-functioning pNET that exceeds 2 cm in diameter, the incidence of distant metastasis is significantly increased, and surgery is recommended. In cases of unresectable pNET, a somatostatin analog has been shown to demonstrate antitumor effects and is considered to be a promising treatment. In addition, molecular-targeted drugs have recently been found to be effective in phase III clinical trials.
Diagnostic Imaging ; Duodenum ; Gastrinoma ; Incidence ; Insulinoma ; Multiple Endocrine Neoplasia ; Multiple Endocrine Neoplasia Type 1 ; Neoplasm Metastasis ; Neuroectodermal Tumors, Primitive ; Neuroendocrine Tumors ; Pancreas ; Pituitary Neoplasms ; Somatostatin

BACKGROUNDPituitary adenomas are common intracranial tumors, with a rising incidence in China. Excision is a mainstay therapy for this disease, and is often carried out via transfrontal, transsphenoidal or transpterional approaches. However, few studies have systematically addressed the regional anatomy involved in these microsurgical procedures. The present study attempted to establish some key anatomic measurements relevant to pituitary adenoma resection based on cadaver and computer tomography (CT) image studies.

METHODSHead specimens from 30 randomly selected formalin-fixed adult cadavers were used for anatomical analysis. Measurements were made on the base of the skull following removal of brain structures above the pituitary gland, and on the mid-sagittal plane of the cranium. Parameters were designed by considering the 3 above-mentioned common microsurgical approaches, and obtained on each head using a sliding caliper. Multi-level CT images from 30 individuals were also used for distance measurements between landmark structures that are relevant to these surgeries. All data were subjected to statistical analysis using the SPSS 11.5 software.

RESULTSThere was statistically significant difference (P < 0.05) of distance measured on cadavers relative to CT images in 3 sets of measurements related to the transfrontal surgical approach, i.e., distances from the midpoint of superciliary arch superior border to the cranial entrance of internal carotid arteries (ICAs), the opposite side entrance of ICA and to the genu of ICA. While regional anatomical analyses were carried out according to the transpterional approach, statistically significant difference was also found in 3 sets of distance measurements between cadaver and CT image data, with regard to the distances between the pterion and some landmark structures around the pituitary.

CONCLUSIONSThe present study provides key anatomical and CT image measurements involving the 3 conventionally used surgical approaches for pituitary tumor resection. The data implicate that while CT scan results can provide valuable guidelines for operations, cautions and adjustments are needed during surgery for sufficient tumor excision and protection of key blood vessels and nerves in the vicinity of the pituitary gland and around the surgical pathway.

Adult ; Female ; Humans ; Male ; Pituitary Gland ; anatomy & histology ; diagnostic imaging ; Pituitary Neoplasms ; diagnostic imaging ; surgery ; Radiography

Radiosurgery, or stereotactic radiosurgery, is a minimally invasive modality to treat a lesion with stereotactically focused ionizing radiation without surgical incision. Because there are no incision procedures, general anesthesia or transfusion is not required, and complications related to incisional procedures do not occur in radiosurgery. As a result, radiosurgery shows much low rates of complications than conventional open surgery with comparable cure rates. In the beginning, radiosurgery was applied only to a few intracranial diseases because a stereotactic frame was applied to the skull. Along with the development of technologies and accumulation of knowledge on radiosurgery such as medical imaging, computer, radiation physics, and radiobiology, indications of radiosurgery have been expanded in various ways. Nowadays, radiosurgery is accepted as an adjuvant treatment or a primary treatment option for many neurosurgical diseases and cancers. Cranial nerve schwannomas, brain meningiomas, pituitary adenoma, and other benign brain tumors are good indications for radiosurgery. Intracranial arteriovenous malformation, brain metastases from extracranial cancers, and trigeminal neuralgia are also well controlled by radiosurgery. Spinal metastases and various cancers are emerging indications for extracranial radiosurgery, which has been recently introduced. In this article, the authors summarized the basic concept, history, development, and future of radiosurgery as an introduction to radiosurgery.
Anesthesia, General ; Brain ; Brain Neoplasms ; Cranial Nerves ; Diagnostic Imaging ; Intracranial Arteriovenous Malformations ; Meningioma ; Neoplasm Metastasis ; Neurilemmoma ; Pituitary Neoplasms ; Radiation, Ionizing ; Radiobiology ; Radiosurgery ; Skull ; Trigeminal Neuralgia