Pharyngeal pituitary non-functioning adenoma with normal intra-sellar gland: massive tumor shrinkage on octreotide therapy

OBJECTIVE: Functioning or non-functioning ectopic tumors may develop from pharyngeal pituitary remnants. They constitute <1% of all obstructive pharyngeal masses and they have a strong tendency to bleed. We report a case of a non-functioning ectopic pituitary adenoma of the rhino-pharynx studied over a long-term somatostatin analog treatment. PATIENT AND TREATMENT: A 60-Year-old woman presented with severe posterior epistaxis. She had complained of nasal obstruction for the past 2 Years. Magnetic resonance imaging (MRI) and endoscopic examination revealed a 2 cm exophytic, bleeding mass in the cavum, which was judged inoperable, and a biopsy was performed. On immunostaining, tumor cells were positive for pancytokeratins MNF 116 and C11, epithelial membrane antigen, chromogranin and neuron-specific enolase (NSE), and negative for synaptophysin, desmin, actin, estrogen and progesterone receptors, all anterior pituitary hormones and human chorionic gonadotropin. Blood levels of the above hormones and tumor markers were normal, except for a moderate elevation of NSE (33.8 microg/l, normal value <12 microg/l). It was concluded that this was a non-functioning pituitary adenoma of the rhino-pharynx. MRI showed a normal intra-sellar pituitary gland, including the normal bright signal of the posterior lobe. Somatostatin receptor scintigraphy (SRS) disclosed intense tracer uptake in the tumor, indicating high somatostatin receptor content. There was also an intense uptake in the intra-sellar pituitary. Therapy with long-acting octreotide was started, 20 mg per Month i.m. RESULTS: The patient has been on octreotide for the last 12 Months. Nasal obstruction rapidly subsided and bleeding did not recur. Repeated endoscopic examinations showed rapid tumor reduction, the mass shrinkage being almost complete at 3 Months. This was confirmed by MRI, while SRS showed markedly decreased uptake in the residual tumor and the intra-sellar pituitary, and NSE became normal. CONCLUSION: Pharyngeal pituitary remnant adenomas are rare, but they must be considered in the differential diagnosis of bleeding or obstructive masses of the rhino-pharynx. In this case, the positive SRS influenced the choice of octreotide, as an alternative to surgery. As we show for the first time in this location, octreotide can exert prolonged and marked anti-tumoral effects in non-functioning adenoma.

Surgical treatment of Cushing's disease

✓ The endocrinological, radiological, surgical, and pathological experience with 34 consecutive patients operated on for Cushing's disease is presented. Preoperative endocrine evaluation demonstrated that 19 patients had “typical” endocrine patterns for pituitary adrenocorticotropic hormone (ACTH)-dependent hypercortisolism and 11 had “atypical” testing. Pituitary pathology was found in 95% of the patients with typical preoperative endocrine testing but in only 55% of those with atypical testing. Eight of 34 preoperative computerized tomography scans demonstrated tumors, which correlated in all instances with the surgical findings. Microadenomas were removed from 25 patients, 22 of whom achieved postoperative remission of endocrine symptoms. Macroadenomas were found in three patients, only one of whom achieved remission after surgery. One patient had removal of an adenoma in the pharyngeal pituitary, and in another an ectopic lung carcinoid was excised; both of these patients were in postoperative remission. Four patients underwent transsphenoidal exploration but no definitive explanation was found for their hypercortisolism; these patients were not in remission. Immunohistochemical staining was performed on every specimen and all tumors showed excessive ACTH-secreting cells. A new rapid stain of the fibrovascular stroma is described.

Human pharyngeal and sellar pituitary glands: differences and similarities revealed by an immunocytochemical study

ABSTRACT Fifteen pharyngeal and sellar pituitary glands, obtained at autopsy from unselected adult patients, were compared in an attempt to elucidate the functional significance of the pharyngeal pituitary. The study was carried out using light microscopy and an indirect peroxidase technique to detect the presence of prolactin, GH, ACTH, LH, FSH, TSH and lipotrophin (LPH) immunoreactive cells. A quantitative analysis of these cell types in each gland was performed. Neither the pharyngeal nor the sellar pituitaries were abnormal in six cases. In this group the average percentage of immunoreactive cells in the sellar vs the pharyngeal pituitary was 11·3 vs 7·4 for FSH cells, 13·3 vs 4·4 for LH cells, 6·4 vs 5·2 for TSH cells, 14 vs 1·5 for ACTH cells, 13·1 vs 6 for LPH cells, 29·4 vs 5·2 for GH cells and 21·2 vs 8·5 for prolactin cells. A comparative statistical evaluation of the seven hormone-producing cell types indicated that, in most cases, the percentage of immunoreactive cells was significantly higher in the sellar pituitary. Examination of serial sections revealed hyperplasia, with or without microadenomas, in nine sellar pituitaries. In these abnormal cases most of the pharyngeal pituitary glands showed hyperplasia of the same cell type as was found hyperplastic in the sellar adenohypophysis. However, hyperplasia restricted to the sellar pituitary was also seen. There were two cases in which the pharyngeal pituitary was almost lacking in immunoreactive cells; in one of them the sellar pituitary had GH and prolactin cell hyperplasia. The results obtained confirm that under normal conditions the pharyngeal pituitary is not an important source of adenohypophyseal hormones. They also suggest that the pharyngeal pituitary, despite its capacity to respond at a cellular level, has a limited potential in terms of volume, and that it is not developmentally programmed to replace the sellar adenohypophysis except when the latter has a serious pathological condition. J. Endocr. (1986) 108, 231–238