Shintaro Mori

Growth hormone-producing pituitary adenoma with crystal-like amyloid immunohistochemically positive for growth hormone.

Growth hormone (GH)‐producing pituitary adenoma from a 50‐year‐old acromegalic female was studied histochemically, immunohistochemically and electron microscopically. The adenoma was characterized by numerous crystal‐like amyloid bodies of 5 to 40 μm in diameter. In the periphery of the crystal‐like amyloid, bundles of amyloid fibrils were closely associated with deep invaginations of adenoma cells. The adenoma cells had numerous vesicles and vacuoles filled with amyloid fibrils, some of which were continuous with extracellular space. The crystal‐like amyloids, as well as the adenoma cells, were immunohistochemically positive for GH. It might be possible that disorder of hydrolysis of “prohormone,” from which GH is elaborated, is responsible for the amyloid production, and that amyloid discharge is accompanied with immunoreactive GH.

Surgical treatment of tumors in the anterior skull base using the transbasal approach.

Five patients with tumors in the anterior skull base were surgically treated using the transbasal approach, which permits removal of the tumor, repair of the dura mater, and reconstruction of the skull base in a one-stage procedure. By using autologous materials for the bone graft and pedunculated pericranial flap for the reconstruction, the intracranial structures are separated from the air-filled nasal and paranasal cavities. No postoperative complications such as wound infection and leakage of cerebrospinal fluid were encountered. The use of this surgical technique makes it possible to extirpate brain tumors that heretofore have been considered unresectable.

Primary myxoma in the pituitary fossa: case report.

A case of primary myxoma in the pituitary fossa is described. The tumor presented as an intrasellar and suprasellar mass and was successfully removed during a transsphenoidal operation. It was verified as a myxoma by histopathological studies, and there was no evidence that it was a metastasis. This is thought to be the first report of this tumor occurring in the pituitary fossa.

Intracavernous Sinus Ectopic Adrenocorticotropin-Secreting Tumours Causing Therapeutic Failure in Transsphenoidal Surgery for Cushing's Disease

Summary Background. The major cause of surgical failure in the treatment of Cushings disease lies in unsuccessful identification of adenomas. In the present study, we investigated the pathogenesis of negative exploration in transsphenoidal surgery for Cushings disease by analyzing neuro-imaging studies, endocrinological examination and selective venous sampling. Methods. Thirty patients with ACTH-dependent Cushings syndrome that met the endocrinological criteria for Cushings disease were treated by transsphenoidal microsurgery. Depending on positive or negative identification of adenomas during the surgery, selective adenomectomy, partial hypophysectomy or subtotal hypophysectomy was performed. Findings. All nine patients who underwent selective adenomectomy showed endocrinological remission and did not need any hormone replacement therapy. Of the 12 patients who underwent partial hypophysectomy, 11 showed normalization of hypercortisolism but seven needed permanent replacement of hydrocortisone. Four patients underwent subtotal hypophysectomy because no adenoma could be identified in spite of detailed exploration, and three of them showed remission but with permanent requirements of hydrocortisone and other pituitary hormones. Five patients, whose hypercortisolism persisted after initial surgery, underwent total hypophysectomy as secondary transsphenoidal surgery, and only one of them showed endocrinological remission. Of the six patients with surgical failure, four were thought to be rare cases in whom the ACTH-secreting tumours may have occurred ectopically in the cavernous sinus without direct contact with the pituitary gland. Endocrinologically, these four patients showed a low or no response to corticotropin releasing hormone (CRH) stimulation, and for three of them, radiation therapy to the sellar region including the cavernous sinus was effective for persistent hypercortisolemia. Interpretation. Recognition of an ectopic intracavernous sinus ACTH-secreting tumour as a pathological entity for Cushings disease may not only enhance the diagnostic accuracy but also be important for determining the optimal surgical mode for persistent Cushings disease.

Primary meningioma of paranasal sinuses treated by the transbasal approach

The authors found the transbasal approach very useful for the treatment of a meningioma originating in the paranasal sinus and massively involving the anterior cranial base. By this approach, both total excision of the tumor and reconstruction of the base of the skull were successfully achieved at the same operation. The usefulness of the transbasal approach as well as the clinicopathologic features of the meningiomas arising in the paranasal sinus are described.

Treatment of prolactinoma based on the results of transsphenoidal operations

Ninety-eight patients (16 male, 82 female) with prolactinomas were treated by transsphenoidal operation. The postoperative course was closely related to the tumor size and the preoperative levels of serum prolactin. In 37 (74%) of 50 patients with microadenomas, the levels of serum prolactin returned to normal postoperatively. There were 48 patients with macroadenomas; 27 of these were expansive and 21 were invasive. In 9 (33%) of the 27 patients with expansive macroadenomas, the postoperative levels of prolactin returned to normal; this was not the case in any of the 21 patients with invasive macroadenomas. Of 81 premenopausal women, 35 (43%) resumed normal menstruation postoperatively. All patients with preoperative deficits in the visual field experienced postoperative improvement. There were no postoperative deaths or serious complications in this series. Our data indicate that microprolactinomas are highly curable by transsphenoidal operation alone. In women who plan to have children, prolactinomas should be removed immediately. On the other hand, in patients with macroprolactinomas who manifest high levels of serum prolactin, initial treatment with bromocriptine should be considered because there is little hope for surgical cure and postoperative bromocriptine treatment might be necessary.

Bifrontal Epidural Hematoma after Transsphenoidal Operation: Report of a Case with a Rare Complication

We report a patient with a growth hormone-secreting adenoma who developed bifrontal epidural hematomas after a transsphenoidal operation. To our knowledge, this is the first report of such a complication.

Hypogonadism of male prolactinomas: Relation to pulsatile secretion of LH: Hypogonadisms des Mannes mit Prolaktinomen: Beziehungen zur pulsatilen LH‐Sekretion

Summary In order to investigate whether a hypothalamic disorder cause hypogonadism in male prolactinomas, LH pulsatile secretion was studied in 13 male patients. Serum PRL levels ranged from 186 to 45, 000 ng ml‐1 before treatment, and all the tumors were macroadenomas. Reduced LH secrection was revealed in 5 of 13 patients, and FSH was reduced in 1 of 13. Serum testosterone (T) levels were lower than the normal limit in all the patients. HCG tests in 3 patients showed good responses, but the peak values of T were lower than those of normal men. LH pulsatilities were examined in 5 hyperprolactinemic patients before treatment, in 4 hyperprolactinemic patients after operation, and in 8 normoprolactinemic patients after operation and/or bromocriptine treatment. There was no significant difference of the mean LH values, the frequencies of LH pulses, and amplitudes among the hyperprolactinemic patients before operation (n = 5), the normoprolactinemic patients after operation (n = 8), and normal men (n = 7). From these results, it was evident that the hypothalamus and pituitary function of male prolactinomas were well preserved, in spite of higher serum PRL levels and larger tumor size than those reported in females. It is suggested that the main cause of hypogonadism in these patients is due to testicular dysfunction resulting from excessive serum PRL.

Annulate lamellae in prolactin-secreting pituitary adenomas

SummaryElectron-microscopic examination revealed the presence of annulate lamellae in four of five prolactinomas. All the patients examined were 24–30-year-old women who had suffered from amenorrhea and galactorrhea for 3–5 years. Serum levels of prolactin were 114–4,700 ng/ml. The tumors removed by a transsphenoidal approach were 4–23 mm in diameter and showed the ultrastructural features of sparsely granulated prolactinoma. Analysis in correlation with clinical and laboratory data revealed that the annulate lamellae were found in rapidly growing prolactinomas. This is the fifth report on pituitary adenomas with annulate lamellae.