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Lewis S Blevins

Publications and source records attributed to Lewis S Blevins.

4 recordsLinked to original sources

The utility of external beam radiation and intracystic 32P radiation in the treatment of craniopharyngiomas.

BACKGROUND: The management of craniopharyngiomas has historically been controversial in terms of the extent of initial surgical resection and the use of additional treatments. Various options include radical excision versus a more conservative surgical approach followed by external beam radiation; most recently, intracystic 32P radiation has been used in selected patients. METHODS: We reviewed our experience with 25 patients with craniopharyngiomas treated between 1984 and 1999 to assess the effectiveness of external beam radiation and intracystic 32P radiation therapy in preventing progression and recurrence of local disease. RESULTS: All patients underwent surgery as a component of initial therapy for their histologically-proven craniopharyngiomas. Fifteen patients additionally received external beam radiation. Forty-five percent of patients who underwent incomplete resections followed by external beam radiation required additional therapy. In contrast, 80% of patients who had incomplete resections without post-operative external beam radiation required further treatment. Seven patients had intracystic 32P colloid injections. Neither of the two patients receiving 32P intracystic radiation as part of their initial therapy needed further treatment. Only one of the five patients receiving 32P intracavitary radiation for disease progression following initial therapy required further intervention. Of the remaining four patients, three enjoyed responses to treatment and one had stable disease. CONCLUSIONS: Our observations support the use of external beam radiation for prevention of tumor progression in adults unable to receive a complete surgical resection. Our results additionally suggest that intracystic 32P radiation results in control of cystic components of craniopharyngiomas in the majority of cases.

Adolescent↗

Hypertension in an adolescent boy.

We report the case of an adolescent boy who presented with hypertension and hypokalemia. A systematic work-up revealed hyperreninemic hyperaldosteronism. Further study revealed Page kidney caused by trauma-associated renal hematoma. The evaluation and management of hyperaldosteronism and Page kidney are discussed.

Adolescent↗

Immunohistochemical localization of carboxypeptidases D, E, and Z in pituitary adenomas and normal human pituitary.

Carboxypeptidases may play important role(s) in prohormone processing in normal and neoplastic adenohypophyseal cells of the pituitary. We have recently demonstrated carboxypeptidase E (CPE) and carboxypeptidase Z (CPZ) in the majority of adenohypophyseal cells with carboxypeptidase D (CPD) immunoreactivity largely confined to adrenocorticotrophs. This study evaluated the expression patterns of CPE, CPD, and CPZ immunoreactivity in 48 pituitary adenomas. Our immunohistochemistry demonstrated extensive intracytoplasmic immunoreactivity for CPE, CPD, and CPZ in adrenocorticotrophic hormone (ACTH)-producing adrenocorticotroph cells, prolactin-producing lactotroph cells, and growth hormone (GH)-producing somatotroph cell adenomas, all of which require carboxypeptide processing of prohormones to produce active endocrine hormones. In contrast to the restricted expression in the normal adenohypophysis, CPD appeared to be widespread in the majority of adenomas, suggesting that CPD levels are increased in adenomas. In luteinizing hormone/follicle-stimulating hormone (LH/FSH)-producing gonadotroph adenomas, which do not require carboxypeptidases to produce gonadotropins, only CPZ immunostaining was demonstrated. In null-cell adenomas, CPE immunoreactivity was detected in the majority of tumors, but CPD and CPZ were identified only in a minority of cases. CPE in these cells may process other peptides critical for pituitary cell function, such as chromogranin A or B. These findings suggest that CPs participate in the functioning of pituitary adenomas.

Adenoma↗