Islet cell carcinomas of the pancreas: a twenty-year experience

Unlike its lethal exocrine counterpart, islet cell carcinoma of the pancreas is an indolent neuroendocrine neoplasm. The majority of these tumors are hormonally active. When functioning, a number of clinical syndromes (for example, hyperinsulinism, Zollinger-Ellison and Cushing's syndromes) may be evident. Fifty-eight patients surgically treated between 1965 and 1984 were retrospectively analyzed. The purpose of this study was to determine the distribution of functioning versus nonfunctioning tumors and the response to type of therapy. Mean postoperative follow-up was 7.4 years. Survival and prognostic indices were calculated by the Kaplan-Meier method and compared with log-rank tests. Of the group, 54% had functioning and 46% nonfunctioning tumors. Gastrinomas were the most common functioning tumors encountered (19%). Of interest was the finding that nonfunctioning tumors increased steadily during the last 15 years of the study (25% to 65%). Curative resections were performed in 15 (26%) and noncurative procedures in 43 patients (74%), with an overall operative mortality rate of 3%. Symptomatic improvement was achieved in 90% (curative) and 51% (noncurative). Survival at 3 years was 87% and 66% for the curative and noncurative groups, respectively (p less than 0.1), with an overall 5-year survival of 42%. The absence of hepatic metastases was a major predictor of survival at 3 years (82% vs 56%, p less than 0.05). Survival was statistically better at 3 years in those patients with gastrinomas compared with patients with nonfunctioning tumors (91% vs 58%, p less than 0.05). Although surgical cure is rare, significant long-term palliation may be achieved in a large percentage of patients with an aggressive surgical approach, occasional total gastrectomy, combination chemotherapy, H2 blockade, when indicated, and, most recently, with the new long-acting analogue of somatostatin.

Peptide YY concentrations in normal ileum and colon and in idiopathic inflammatory bowel disease

Concentrations of the candidate endocrine and paracrine peptide, peptide YY, were measured by specific radioimmunoassay in tissue extracts prepared from normal ileum, normal colon, Crohn's disease, and ulcerative colitis. In both the ascending and descending colon, there were significantly decreased mean concentrations of peptide YY in Crohn's colitis and ulcerative colitis, compared to mean concentrations in normal colon. There was no age-related decrease of concentrations of peptide YY in normal colon. The decrease in concentrations of peptide YY in colon obtained from patients with inflammatory bowel disease did not appear related either to the duration of the clinical symptoms of the disease or to the severity of colonic inflammation. Further studies of the physiological function of peptide YY in man are needed to determine whether these findings might be useful in understanding a component of the pathophysiology of idiopathic inflammatory bowel disease.

Spontaneous contractions and some electrophysiologic properties of circular muscle from normal sigmoid colon and ulcerative colitis

Spontaneous contractions, inhibitory responses produced by electrical field stimulation, and some electrophysiologic properties of circular smooth muscle from normal sigmoid colon and from sigmoid colon of ulcerative colitis patients were compared in vitro using simultaneous recordings of mechanical and intracellular electrical activity. In normal colonic circular muscle obtained from 21 patients, the frequency of spontaneous summation contractions ranged from 3 to 7 per 4 min, whereas in circular muscle from 13 patients with ulcerative colitis, the frequency of these contractions ranged from 1 to 9 per 4 min. Nonadrenergic, noncholinergic relaxation produced by electrical field stimulation was recorded in the majority of circular smooth muscle strips from both normal colon and colon from patients with ulcerative colitis. There were no significant differences in mean resting membrane potential, mean slow-wave frequency, mean maximum slow-wave amplitude, or inhibitory-junction potential amplitudes recorded using circular smooth muscle from both normal colon and colon from patients with ulcerative colitis. There appeared to be a weak association in patients with ulcerative colitis between increasing duration of symptoms and decreasing frequency of spontaneous summation contractions, but there were no associations between the frequency of these contractions and the severity of colonic inflammation, patient age, or the frequency of stools. The mechanism accounting for a wider range in the frequency of summation contractions recorded from colonic circular smooth muscle in ulcerative colitis remains to be determined.

New rapid latex agglutination test for diagnosing Trichomonas vaginalis infection

A newly developed latex agglutination test for Trichomonas vaginalis infection was compared for sensitivity, specificity, efficiency, and positive and negative predictive values with microscopy, culture, and an enzyme linked immunosorbent assay (ELISA) in the diagnosis of 395 women attending a genitourinary medicine clinic. T vaginalis infection was diagnosed in 42 (11%) women. The sensitivities of both the latex agglutination test and the ELISA were 95% compared with 74% for microscopy and 76% for culture. The latex test was specific and showed no cross reaction with a wide range of other genital tract infections. The latex agglutination test can detect antigen in both soluble and insoluble forms, and as it is simple to perform, can be undertaken during routine examination without recourse to special equipment or training. Further evaluation is required.

Distribution, quantitation, and origin of immunoreactive neuropeptide Y in the human gastrointestinal tract

A radioimmunoassay for measurement of immunoreactive neuropeptide Y has been developed using antiserum from a rabbit (221) immunized with porcine neuropeptide Y. Antibody 221 has been characterized for both sensitivity and specificity. To determine the distribution of neuropeptide Y in the human gastrointestinal tract, fresh tissue specimens were separated by microdissection into the muscularis externa and the mucosa-submucosa. To examine the origin of neuropeptide Y in human colon, specimens of aganglionic and ganglionic colon were obtained from patients with Hirschsprung's disease. Immunoreactive neuropeptide Y in human gut was present in highest concentrations in the muscularis externa of the stomach and in lowest concentrations in the muscularis externa of the ileum and descending colon. Neuropeptide Y in the stomach was present in higher concentrations in the muscularis externa than in the mucosa-submucosa, but in the descending colon there were lower concentrations of neuropeptide Y in the muscularis externa than in the mucosa-submucosa. In Hirschsprung's disease, concentrations of neuropeptide Y were increased in aganglionic colon in both the muscularis externa and the mucosa-submucosa, compared to corresponding layers from proximal ganglionic colon. Extracts of the gastric muscularis externa and the colonic mucosa-submucosa were separated by C18 reverse-phase high-performance liquid chromatography. One major immunoreactive species was identified by radioimmunoassay which eluted in a position similar to synthetic human neuropeptide Y. These results demonstrated both regional and layer differences in concentrations of neuropeptide Y in human gut. Increased concentrations of neuropeptide Y in aganglionic colon from Hirschsprung's disease most likely result from enlargement of neuropeptide Y-containing extrinsic nerve fibers in both the mucosa-submucosa and the muscularis externa.

Ectopic ACTH syndrome caused by a bronchial carcinoid tumor responsive to dexamethasone, metyrapone, and corticotropin-releasing factor

Cushing's syndrome due to bronchial carcinoid tumors that secrete adrenocorticotropin (ACTH) may be difficult to distinguish from pituitary Cushing's disease, since the responses to dexamethasone and metyrapone are sometimes similar. Recently, the ACTH and cortisol responses to ovine corticotropin-releasing factor (oCRF) have been shown to be different in pituitary Cushing's disease than in Cushing's syndrome due to other causes. It is not known if the response to oCRF can distinguish pituitary Cushing's disease from those ACTH-secreting bronchial carcinoid tumors that respond to dexamethasone and metyrapone. A case of Cushing's syndrome due to an ACTH-secreting bronchial carcinoid is described in which the responses to dexamethasone, metyrapone, and oCRF were indistinguishable from the responses observed in pituitary Cushing's disease. A bronchial carcinoid tumor should be considered even when responses to dexamethasone, metyrapone, and oCRF suggest pituitary Cushing's disease.

Decreased colonic peptide histidine-methionine in idiopathic inflammatory bowel diseases

The sequence for peptide histidine-methionine is present within the same preprohormone as vasoactive intestinal polypeptide. Since our previous study using radioimmunoassay had demonstrated significantly decreased colonic concentrations of vasoactive intestinal polypeptide in ulcerative colitis and Crohn's colitis compared to normal colon, we determined the distribution and quantitation of peptide histidine-methionine. Fresh surgical specimens were dissected into mucosal-submucosal and muscularis externa layers prior to acid extraction and specific radioimmunoassay. One immunoreactive species that appeared to coelute with peptide histidine-methionine was separated by reverse-phase high-performance liquid chromatography. Mucosal-submucosal concentrations of peptide histidine-methionine were significantly decreased in ulcerative colitis and Crohn's colitis, compared to those in normal colon. In normal ileum and colon, linear correlation analysis showed no relationship between patient age and tissue concentrations of peptide histidine-methionine. However, a parallel decrease in molar concentrations of peptide histidine-methionine and vasoactive intestinal polypeptide in ulcerative colitis and Crohn's colitis was demonstrated by linear correlation analysis. These results are consistent with the hypothesis that peptide histidine-methionine and vasoactive intestinal polypeptide are colocalized within the same neural structures that have been altered in the idiopathic inflammatory bowel diseases.

Somatostatin in the idiopathic inflammatory bowel diseases

To study the effect of mucosal inflammation on tissue concentrations of somatostatin, the distribution and concentration of somatostatin in specimens of normal and abnormal (ulcerative colitis and Crohn's disease) ileum and colon were determined by a specific radioimmunoassay. Each tissue specimen obtained at surgery was separated by microdissection into the mucosa-submucosa and the muscularis externa. Immunoreactive somatostatin was acid-extracted from each layer before measurement. Gel chromatography was used to characterize immunoreactive somatostatin measured by radioimmunoassay; somatostatin-28 was the major immunoreactive species measured in human intestine. In normal colon, concentrations of somatostatin were not related to patient age. Concentrations of immunoreactive somatostatin in the mucosa-submucosa of the descending colon were significantly decreased in ulcerative colitis and in Crohn's colitis, compared with normal colon. There was no apparent relationship between concentrations of somatostatin and the duration of inflammatory bowel disease. However, somatostatin concentrations appeared to be lower in patients with severe colitis than in patients with minimal colitis. The decrease in mucosal-submucosal concentrations of somatostatin is in agreement with previous morphologic studies, which have suggested diminished populations of endocrine cells in ulcerative colitis. The possible role of somatostatin in the colon suggests that further studies of the alteration of this gut peptide may be useful in understanding a component of the pathophysiology of idiopathic inflammatory bowel disease.

Idiopathic chronic constipation is associated with decreased colonic vasoactive intestinal peptide

To investigate the reported association between idiopathic chronic constipation and morphologic abnormalities of enteric nerves, we measured the concentrations of six neuropeptides, vasoactive intestinal peptide, peptide histidine-methionine, substance P, methionine5-enkephalin, neuropeptide Y, and the bombesinlike intestinal peptides, in descending colon from 4 patients with idiopathic chronic constipation. Decreased concentrations of vasoactive intestinal peptide (707 +/- 112 ng/g wet tissue) and peptide histidine-methionine (543 +/- 58 ng/g) were found in the muscularis externa obtained from constipated patients compared with normal concentrations (40 patients) of vasoactive intestinal peptide (1199 +/- 47 ng/g) and peptide histidine-methionine (815 +/- 45 ng/g). Vasoactive intestinal peptide was identified by immunocytochemistry in nerve fibers within the circular smooth muscle layer of descending colon obtained from 6 control patients, but not in nerve fibers within the circular smooth muscle of descending colon obtained from 3 patients with idiopathic chronic constipation. By contrast, the distribution of immunoreactive met5-enkephalin was similar in normal descending colon and in descending colon obtained from patients with idiopathic chronic constipation. Decreased colonic concentrations of vasoactive intestinal peptide (a candidate nonadrenergic, noncholinergic inhibitory neurotransmitter) may be associated with diminution of inhibitory innervation of colonic circular smooth muscle in some patients with idiopathic chronic constipation.

Amiodarone-associated thyrotoxicosis (AAT): experience with surgical management

Amiodarone (Cordarone), a benzofuran derivative containing two atoms of iodine per molecule (37% of molecular weight), has recently been released in the United States for the management of refractory cardiac arrhythmias. While it was still under investigation, 529 patients were managed with this drug at the Mayo Clinic between 1981 and 1986; eight of them (1.5%) had thyrotoxicosis 12 to 37 months (median, 28 months) after initiation of treatment. Low 24-hour iodine-131 uptake (less than 4%) and recognized refractoriness to thionamide treatment precluded the use of radioablation or antithyroid drugs. Cessation of the amiodarone treatment was considered undesirable from a cardiac standpoint. Near-total thyroidectomies were undertaken in six patients, and rapid correction of hyperthyroidism followed. There were no intraoperative or postoperative arrhythmias. The median postoperative hospital stay was 4.3 days (range, 2 to 13 days). Subsequently, all patients required thyroid hormone replacement. Near-total thyroidectomy has proved a safe and effective treatment for amiodarone-associated thyrotoxicosis in patients who required drug continuation.

Ocular pigmented spots and eyelid myxomas

Ophthalmic abnormalities are part of a recently recognized syndrome that includes myxomas, spotty pigmentation, and endocrine overactivity. The complex is familial with mendelian dominant mode of inheritance. The 63 patients (27 males and 36 females) we have identified with this complex had the following ophthalmic abnormalities: facial and eyelid lentigines in 44 patients (70%); pigmented lesions on the caruncle or conjunctival semilunar fold in 17 patients (27%); and eyelid myxomas in ten patients (16%). Because these findings usually preceded the most serious component of the syndrome, cardiac myxoma, early recognition of their significance is important.

Identification and distribution of immunoreactive peptide YY in the human, canine, and murine gastrointestinal tracts: species-related antibody recognition differences

A radioimmunoassay using two antisera (antibody 80 and antibody 213) from rabbits immunized with porcine peptide YY has been characterized for both sensitivity and specificity. To determine the distribution of peptide YY in the gut, fresh tissue specimens from the human and canine gut were separated into mucosal-submucosal and muscularis externa layers by microdissection. These tissues and transmural specimens from murine gut were acid-extracted and neutralized, followed by radioimmunoassay using each antiserum. Immunoreactive peptide YY in canine and murine gut was present in similar concentration and distribution using each antiserum, with highest concentrations in the mucosal-submucosal layer of the descending colon. Using antibody 213, immunoreactive peptide YY throughout the human gut was measured only at the lower detection limit of the radioimmunoassay. By contrast, using antibody 80, peptide YY in human gut was present in a distribution similar to canine and murine gut. Using antibody 80, one major immunoreactive species was identified with C18 reverse-phase high-performance liquid chromatography in extracts of human, canine, and murine colon. These results suggest species-related antibody recognition differences. The similar concentrations of peptide YY in canine and murine gut determined with the two antisera are consistent with the hypothesis that the amino acid sequences of canine and murine peptide YY are similar to porcine peptide YY. Using antibody 213, the low concentrations of immunoreactive peptide YY found in human gut are consistent with the hypothesis that human and porcine peptide YY have different amino acid sequences. Antisera prepared by immunization with porcine PYY must therefore be carefully characterized prior to studies using human sera or human tissue extracts.

Hyalinizing trabecular adenoma of the thyroid gland

The hyalinizing trabecular adenoma, a distinctive lesion, is important because it may mimic medullary and papillary carcinoma microscopically. We describe 11 such tumors obtained from women ages 27-72 years (mean, 46 years). The initial pathologic diagnoses were carcinoma (five cases), adenoma (two cases), paraganglioma (one case), and "indeterminate" (three cases). None of the tumors recurred or metastasized (mean follow-up, 10 years). Grossly, the neoplasms measured 0.3-4 cm in diameter, and were yellow-tan and circumscribed. Microscopically, they were encapsulated or circumscribed and solid, or vaguely lobulated. The polygonal, oval, and elongated tumor cells were arranged in trabeculae, clusters, or both, and were often inserted vertically into capillaries. The sharply outlined cells had finely granular cytoplasm that was either acidophilic, amphophilic, or clear. Typical features included oval and elongated nuclei, perinucleolar vacuoles, acidophilic nuclear inclusions, fine nuclear grooving, and infrequent mitotic figures. Perivascular hyaline fibrosis and cell degeneration mimicked amyloid, but these tumors were Congo red-negative. Occasional trabeculae featured round or irregularly shaped follicles, sometimes with papillary infoldings, that were either empty or contained colloid-like material and psammoma bodies. Immunostaining of tumor cells was positive for thyroglobulin and negative for calcitonin. Among six tumors analyzed by flow cytometry, five displayed a diploid pattern and one showed an aneuploid peak.

Pituitary adenomas of the multiple endocrine neoplasia type I syndrome

In a series of 1,500 pituitary adenomas surgically resected at Mayo Clinic, 41 (2.7%) occurred in the setting of multiple endocrine neoplasia, type I (MEN-I). Of the 40 patients (18 males, 22 females), 21 (52%) presented with clinical evidence of a pituitary neoplasm, 13 with hyperparathyroidism, and two with functional islet cell tumor. Of the 41 tumors, 11 (27%) were microadenomas, and 30 (73%) were macroadenomas. Immunocytochemical studies demonstrated the following reactivities: GH (4), GH/PRL (6), GH/PRL/glycoprotein (7), GH/ACTH/glycoprotein (1), PRL (16), PRL/TSH (1), ACTH (3), and null cell adenoma (3). We conclude that, in comparison with pituitary adenomas occurring in the general population, those occurring in association with MEN-I are (1) more often endocrinologically functional, (2) more frequently GH- or PRL-producing, and (3) clinicopathologically similar in terms of the subjects age and sex as well as of tumor size and invasiveness.

Chromosomally abnormal clones and nonrandom telomeric translocations in cardiac myxomas

Cardiac myxomas from eight patients were examined cytogenetically in short-term cultures. Cultures could not be established in two of the eight cases. Chromosomally abnormal clones occurred in two of the myxomas; their karyotypes were 45,X,-Y,+7,-18 and 45,X,-Y. In three other myxomas, we found a rare kind of telomere-to-telomere translocation between chromosomes. The telomeres predominantly involved in these three tumors were the 2qter (the end of the long arm of chromosome 2), the 12pter (the end of the short arm of chromosome 12), and Yqter (the end of the long arm of the Y chromosome), respectively. In one other myxoma, 20% of the cells were tetraploid. These findings support the concept that myxomas are neoplastic; those with an abnormal clone may even have malignant potential. The unusual telomere-to-telomere translocations were not observed in a clonal pattern. They may represent a specific type of chromosomal instability associated with a defect in repair or replication of telomeric DNA.

Use of slide latex agglutination test for rapid diagnosis of vaginal candidosis

A new slide latex agglutination test was compared with microscopy and culture for diagnosing vaginal candidosis in 367 women attending a genitourinary medicine clinic. Vaginal candidosis occurred in 10% of the patients, and 7% had commensal carriage of Candida spp. The slide latex agglutination test was superior to microscopy in immediate diagnosis and was rapid and simple to perform. Of the patients with vaginal candidosis, 72% were detected by slide latex agglutination test compared with 38% by microscopy. The test discriminated well between patients yielding cultures of Candida spp who had symptoms and signs and those who showed commensal carriage.

Distribution and quantitation of gut neuropeptides in normal intestine and inflammatory bowel diseases

To study hyperplasia of peptidergic nerves purported to be diagnostic of Crohn's disease, we determined the distribution and concentrations of gut neuropeptides in specimens of normal intestine, ulcerative colitis, and Crohn's disease. Tissue specimens obtained at surgery were dissected into the mucosal-submucosal and muscularis externa layers, and immunoreactive gut neuropeptides were acid-extracted for measurement by radioimmunoassay. The immunoreactive species were characterized by column chromatography. Mucosal-submucosal layer concentrations of vasoactive intestinal peptide were significantly decreased in Crohn's colitis and ulcerative colitis, while mucosal-submucosal layer concentrations of substance P were significantly increased in left-sided ulcerative colitis. Muscularis externa layer concentrations of vasoactive intestinal peptide and met5-enkephalin were decreased in left-sided Crohn's colitis. These neuropeptide concentration abnormalities did not clearly differentiate between Crohn's colitis and ulcerative colitis, and no increase in concentration of a neuropeptide diagnostic of Crohn's disease was identified.

Pathology of the thyroid in amiodarone-associated thyrotoxicosis

Among 83 consecutive patients operated on for thyrotoxicosis at the Mayo Clinic between January 1, 1980 and May 1, 1986, four had a combination of pathologic findings that were similar and unexpected: involutional changes; degenerative and destructive follicular lesions; and zones of fibrosis. These four, but none of the remaining 79, were being treated with amiodarone for cardiac tachyarrhythmias; this drug is known to be taken up by the thyroid gland. Characteristically, small groups of involuted follicles exhibited varying degrees of damage ranging from degenerative changes in a few lining cells to total follicular destruction. Damaged follicular cells were swollen and featured granular or vacuolated cytoplasm. This type of cytoplasmic alteration has been reported to occur in pneumocytes and hepatocytes damaged by amiodarone. Therefore, the drug probably is the cause of the thyroid cell damage, and follicular disruption (with consequent release of iodothyronines into the circulation) is likely to be an important contributor to the associated thyrotoxicosis.

Mucocutaneous pigmented spots and oral myxomas: the oral manifestations of the complex of myxomas, spotty pigmentation, and endocrine overactivity

The complex of myxomas, spotty pigmentation, and endocrine overactivity is a recently recognized syndrome, transmitted as an autosomal dominant trait. The most serious component of the disorder is cardiac myxoma, which has caused the death of one fourth of the affected patients and serious disability in an equal number. It is, therefore, important to recognize patients at risk from the syndrome and, in particular, to test them for cardiac myxoma. Fortunately, in many patients the myxoma complex has a clearly visible marker: mucocutaneous pigmentation. Among 58 patients with the syndrome, spotty facial pigmentation was present in 36 (62%), and 29 (50%) of these also had pigmented spots on their lips. This type and distribution of pigmentation should be a clue to the possible presence of the complex of myxomas, spotty pigmentation, and endocrine overactivity, and patients thus affected should be referred for further investigation. Oral cavity myxoma(s) occurred in four patients with the syndrome.

Multiple adenomatous polyps arising in a continent reservoir ileostomy

In a 29-year-old man who presented with leakage from a continent ileostomy after proctocolectomy, endoscopic evaluation of the reservoir revealed extensive adenomatous polyposis. The polyps were not present at the time of revision of the reservoir 4 years earlier. Because it was not possible to fashion an adequate nipple valve in the presence of so many polyps and the concern over possible malignant transformation, the reservoir was excised. This is the second reported case of polyposis involving a continent reservoir ileostomy. Patients with a continent ileostomy constructed after proctocolectomy for polyposis coli should be evaluated endoscopically at regular intervals.

Primary pigmented nodular adrenocortical disease: diagnosis and management

A rare cause of Cushing's syndrome appearing to originate in the adrenal glands is primary pigmented nodular adrenocortical disease (PPNAD). It may be variably associated with a complex of other pathologic characteristics that include cardiac myxomas, cutaneous myxomas, and lentigines, mammary myxoid lesions, testicular tumors, pituitary adenomas, and neuroectodermal tumors. We have reviewed the clinical, biochemical, radiographic, operative, and pathologic details of seven patients with PPNAD who have been evaluated at Mayo Clinic. Biochemical testing supported autonomous adrenal hyperfunction. This was based on the failure of cortisol suppression by high-dose dexamethasone, failure of pituitary stimulation by metyrapone administration, either normal or suppressed basal adrenocorticotropic hormone (ACTH) levels, normal radiographic studies of the sella turcica, and normal abdominal and thoracic computerized tomography in search of an ectopic ACTH-producing tumor. Six patients underwent bilateral total adrenalectomy without postoperative complications. Nelson's syndrome has not occurred, but acute adrenocortical insufficiency may have contributed to the death of one patient. To recognize the possible diagnosis of PPNAD preoperatively is important to proceed directly with adrenalectomy, avoiding unnecessary pituitary surgery. Moreover, if PPNAD is part of the broader pathologic complex, the possible presence of cardiac myxomas that may be multiple, recurrent, in atypical locations, and familial must be borne in mind.

Duodenal gangliocytic paraganglioma. Clinicopathologic and immunocytochemical study of 11 cases

The clinicopathologic features of 11 cases (8 in men) of duodenal gangliocytic paraganglioma are presented. The patients averaged 56 years of age; none showed evidence of phakomatosis. Ten tumors occurred in the second portion of the duodenum, and one arose in the third portion. All tumors were polypoid, and half presented with gastrointestinal bleeding. The neoplasms were composed of paraganglioma and carcinoid-like elements, neurons, and Schwann as well as sustentacular cells. All tumors behaved in a benign fashion after local resection or snare polypectomy; long-term follow-up (1-25 years; mean, 8.3 years) showed no recurrence in any case. Immunocytochemical examination demonstrated the presence of somatostatin, serotonin, and human pancreatic polypeptide within endocrine cells and neurons.