A phase II trial of gefitinib in patients (pts) with progressive metastatic neuroendocrine tumors (NET): A Phase II Consortium (P2C) study

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Background: Systemic treatment options for progressive metastatic NET, including islet cell carcinoma (ICC) and carcinoid tumor (CT), are limited. These tumors frequently express the epidermal growth factor receptor (EGFR). Gefitinib, a small-molecule inhibitor of the EGFR tyrosine kinase, has been shown to inhibit the growth of NET cell lines. Methods: Eligibility criteria included: radiographic progression by RECIST criteria, ECOG PS ≤ 2, ≤ 1 prior chemotherapy, and good organ function. Prior interferon and prior or concurrent octreotide (if disease progression documented on stable dose) were allowed. Pts received gefitinib 250 mg po daily. We evaluated 6 month (mos) progression-free survival (PFS) in two cohorts (ie, CT and ICC) using separate 2-stage phase II designs. 6 mos PFS rates of 30% (CT) and 10% (ICC) were considered promising. Results: 96 pts were enrolled: (57 CT, 39 ICC). For pts evaluable for the primary endpoint, 23 of 38 (61%) CT pts and 9 of 29 (31%) pts with ICC were progression-free at 6 mos. 1 PR and one minor response (MR = 20–29% decrease in sum of target lesion diameters) were observed in 40 CT pts; 2 PR and 1 MR in 31 ICC pts. In addition, 32% (12/38) of CT and 14% (4/29) of ICC pts had stable disease on study for a duration that exceeded by at least 4 months the time to progression documented prior to study entry. Grade 3–4 toxicity was infrequent with fatigue (6%), diarrhea (5%) and rash (3%) most common. Evaluation of markers of the EGFR pathway on tumor tissue will be presented. Conclusions: Gefitinib is well-tolerated and results in prolonged disease stabilization in pts with prior documented objective progression of CT and ICC, with rare objective responses. Supported by NOI CM17104.

No significant financial relationships to disclose.

Chromatic and achromatic transient VEPs in adults with Down syndrome

Oculo-visual abnormalities such as strabismus and high refractive error are common in people with Down syndrome, and account in large part for reduced visual function in this group. In the absence of such abnormalities, however, some spatial vision deficits persist, probably reflecting abnormal function of the neural visual pathway in this population. In addition, colour vision abnormalities are reportedly common in subjects with Down syndrome. We recorded transient visual evoked potentials in response to black-white and chromatic stimuli, in seven subjects with Down syndrome and 33 controls, to investigate function of the visual pathways underpinning spatial and chromatic visual function in Down syndrome. Our findings indicate, in agreement with previous studies, that retino-striate achromatic and chromatic processing in Down syndrome are abnormal. We find, however, that abnormal retino-striate processing of chromatic signals in this group may not give rise to colour vision deficits detected by the Colour Vision Test Made Easy or the City University test.

Effects of chemotherapy on endogenous erythropoietin levels and the pharmacokinetics and erythropoietic response of darbepoetin alfa: a randomised clinical trial of synchronous versus asynchronous dosing of darbepoetin alfa

The introduction of longer-acting erythropoietic agents into the practice of oncology has demanded an understanding of the interaction of chemotherapy with the pharmacokinetics and haematological effects of these erythropoietins. We report results of a randomised trial comparing the haematological effects of darbepoetin alfa, 6.75 mug/kg, administered once every 3 weeks to anaemic cancer chemotherapy patients on either an asynchronous (day 15) or synchronous (day 1) schedule relative to their every-3-week chemotherapy. A total of 81 patients were randomised and received the study drug (43 asynchronous; 38 synchronous). No difference was observed between groups in the primary endpoint of mean haemoglobin change after 6 weeks of therapy (P=0.45) and change scores were similar to those observed with standard weekly darbepoetin alfa therapy. In a subset of patients evaluated with intensive pharmacokinetic sampling, an increase in endogenous erythropoietin concentration (up to 4-fold) lasting approximately 1 week following chemotherapy administration was observed in both groups. Synchronous administration of darbepoetin alfa was associated with a 1.3-fold increase in the area under the darbepoetin alfa concentration-time curve compared with asynchronous administration. Our data suggest that darbepoetin alfa is effective administered every 3 weeks regardless of timing of administration with respect to chemotherapy and that receptor-mediated uptake by the erythron may be an important clearance mechanism for erythropoietic proteins.

Cushing's disease due to plurihormonal adrenocorticotropic hormone and gonadotropin-producing pituitary adenoma

A 67-year-old woman presented with clinical features of hypercortisolism in association with an invasive pituitary macroadenoma. Adrenocorticotropic hormone (ACTH)-dependent Cushing's disease was documented, and the resected tumor was chromophobic, weakly positive with periodic-Schiff reagent, and showed immunostaining for ACTH and beta-endorphin in a minority of adenoma cells. Both luteinizing hormone and alpha-subunit staining were also observed, but no follicle-stimulating hormone reactivity was seen. Ultrastructurally, the tumor showed typical features of a gonadotroph adenoma of female type. Immunoelectron microscopy showed that ACTH was not produced in corticotrophs, but in cells with the characteristic features of gonadotrophs. This represents the second report of a plurihormonal gonadotroph adenoma producing sufficient ACTH to result in pituitary-dependent Cushing's disease.

Msh2 DNA mismatch repair gene deficiency and the food-borne mutagen 2-amino-1-methy1-6-phenolimidazo [4,5-b] pyridine (PhIP) synergistically affect mutagenesis in mouse colon

Msh2 deficiency and food-borne carcinogen PhIP have been implicated as genetic and environmental factors, respectively, in human colon carcinogenesis. It is not clear whether loss of one or both alleles of Msh2 gene increases the mutational sensitivity in colon when exposed to environmental carcinogens. In the current study, Msh2(+/-)/lacI and Msh2(-/-)/lacI double transgenic mice were treated with PhIP and mutations in the lacI gene were studied in the colon. The spontaneous mutation frequency (MF) is approximately eightfold higher in Msh2(-/-) mice than in Msh2(+/+) mice, while Msh2(+/-) mice display similar levels of spontaneous mutation as the Msh2 wild type mice. PhIP induced a significant increase in MF in all genotypes of mice. However, induced MF is much higher in Msh2(-/-) mice compared to Msh2(+/+) and Msh2(+/-) mice. Msh2(+/-) mice displayed an increased level of G:C>T:A transversions and -1 frameshifts upon PhIP treatment. In contrast, loss of both Msh2 alleles mainly results in increased frequency of G:C>A:T transitions when exposed to PhIP. These results suggest that a defect in mismatch repair may result in an enhanced sensitivity from exposure to a dietary carcinogen. It also provides insight into interaction between genetic and environmental factors in human carcinogenesis.

Adrenocortical carcinoma: surgical progress or status quo?

HYPOTHESIS

Outcome of patients with adrenocortical carcinoma (ACC) has improved with the advent of more widely available and higher quality imaging. Operative management strategies and use of adjuvant therapy have not changed.

DESIGN

Retrospective review of patient histories, imaging studies, operative data, adjuvant therapy, and outcomes at a single institution. Follow-up was complete for a mean of 53 months. Data was compared with prior institutional experience.

SETTING

Tertiary care referral center.

PATIENTS

All patients undergoing operative management for ACC during the period from 1980 to 1996.

MAIN OUTCOME MEASURES

Determinants of recurrence, survival, and the effect of adjuvant therapy on overall outcome.

RESULTS

Fifty-eight patients (30 men, 28 women) with a mean age of 53 years underwent primary operative management for ACC. Functional tumors were identified in 27 patients (47%). Mean tumor size was 12.5 cm. Stage according to the TNM staging system (AJCC Cancer Staging Manual) at presentation was I (n = 0), II (n = 30), III (n = 7), and IV (n = 21). Surgical management included curative resection in 41 (71%), noncurative resection in 14 (24%), and open biopsy in 3 (5%). Perioperative mortality was 5%. Recurrence occurred in 30 patients (73%) with a median time to recurrence of 17 months. Five-year survival by the Kaplan-Meier method was 37%. Prognostic factors (P<.05) included functional status, stage, and chemotherapy in stage III/IV patients. When compared with our prior institutional experience (1960-1980), current patients were more likely to present with stages I to II (52% vs. 34%), have curative resections (71% vs. 50%), and have improved 5-year survival (37% vs. 16%).

CONCLUSIONS

(1) Surgical resection remains the principal treatment for stage I to III disease. (2) Adjuvant therapy may improve survival in patients with stage III or IV disease. (3) Current patients were more likely to present at an earlier stage, undergo curative resections, and have improved 5-year survival than institutional historical comparisons.

Kinetic changes associated with load carriage using two rucksack designs

This study assessed changes in kinetics from unloaded walking associated with load carriage using both a traditional and a new rucksack design that incorporates front balance pockets (AARN). Nine subjects walked at 3(+/-0.05) km x h(-1) over a force plate unloaded and carrying 25.6 kg in each of the rucksacks. The order of trials was randomized and speed-controlled by use of photoelectric cells and a millisecond timer. Anteroposterior and vertical ground reaction forces were analyzed using repeated measures ANCOVA (speed covariate). There was a trend for the AARN pack to elicit a shorter support time than the traditional pack, 1.025+/-0.049 versus 1.037+/-0.06 s (p = 0.056), while the unloaded condition produced the shortest support time, 1.016+/-0.04 s. Both braking and propulsive forces for the rucksacks were significantly greater than for unloaded walking. While there was no significant difference between the packs for the braking force, the AARN pack produced a significantly lower (p<0.05) propulsive force than the traditional rucksack, 0.79+/-0.2 versus 0.94+/-0.16 N x kg bodyweight(-1). Both rucksacks produced significantly greater (p<0.001) vertical force peaks than unloaded walking, the increases being proportional to the increase in system weight. These findings indicate that there may be some advantage in terms of propulsive force production for the front/back system.

Immunolocalization of vascular endothelial growth factor in the GH3 cell line

The question of whether vascular endothelial growth factor (VEGF) is expressed in the GH3 cell line was investigated using immunocytochemistry, immunoelectron microscopy, and Western blotting. Using immunocytochemistry, VEGF was demonstrated in approximately 90% of the cells. Immunopositivity was localized mainly in the paranuclear Golgi region. In a small minority of cells, diffuse cytoplasmic immunostaining was also noted. By immunoelectron microscopy VEGF was evident in the secretory granules, cytoplasmic vesicles, rough endoplasmic reticulum, and the Golgi apparatus. Western blotting confirmed the results of the morphologic studies. It can be concluded that VEGF, which is know to induce angiogenesis and to increase vascular permeability, is produced in the prolactin- and growth hormone (GH)-secreting GH3 cell line. The functional role of VEGF in the GH3 cells is unknown. It is possible that this growth factor affects endocrine activity of GH3 cells by a paracrine mechanism.

The oxygen consumption associated with unloaded walking and load carriage using two different backpack designs

The purpose of this study was to assess the energy expenditure associated with load carriage using both a traditional rucksack and a new rucksack design, the AARN rucksack, which incorporates front balance pockets. Nine volunteers walked at 3 km h(-1) at various uphill and downhill gradients on a treadmill without a load and carrying a load of 25.6 kg in each of the rucksacks. The oxygen consumption associated with both of the loading conditions was significantly (P < 0.001) higher than that associated with unloaded walking at all downhill gradients tested, although there was no significant difference between the two loading conditions. During the uphill gradients the oxygen consumption associated with the AARN pack was significantly (P < 0.05) lower than that associated with the traditional pack at the 0%, 5%, 10% and 20% gradients. The mean (%) differences at these gradients, expressed in ml x kg(-1) x min(-1) were 1.18 (9%), 1.45 (8%), 1.76 (8%) and 1.88 (6%), respectively. On average for the whole protocol, the oxygen consumption associated with the AARN rucksack was 5% lower than that associated with the traditional rucksack [mean (SD) 17.28 (7.46) ml x kg(-1) x min(-1) for the AARN pack and 18.20 (7.84) ml x kg(-1) x min(-1) for the traditional pack]. The findings of the present study suggest that a load carriage system that allows the load to be distributed between the back and font of the trunk is more appropriate for carrying relatively heavy loads than a system that loads the back only.

Nitric oxide synthase and cGMP activity in the salivary glands of the American dog tick Dermacentor variabilis

We colocalized nitric oxide synthase (NOS) activity in epithelial cells that surround the salivary gland duct in female Dermacentor variabilis with NADPH diaphorase histochemistry and immunohistochemistry using a polyclonal anti-endothelial NOS. Using size-exclusion chromatography, a fraction with a molecular mass of about 185 kDa that had diaphorase activity was eluted from tick salivary gland homogenate. This fraction converted arginine to citrulline with the production of nitric oxide (NO), which was detected by using electron spin resonance spectroscopy. The complete activity of the diaphorase fraction was dependent on NADPH, FAD, tetrahydrobiopterin, calmodulin, (CaM), and Ca(2+), but was not dependent on dithiothreitol. The arginine analog N(G)-monomethyl-L-arginine inhibited the activity of this fraction. NO and arginine activated soluble guanylate cyclase to produce cGMP in dopamine-stimulated isolated salivary glands. Dopamine-stimulated isolated salivary glands treated with tick saline containing either EDTA, the NOS inhibitor N(G)-nitro-L-arginine methyl ester, or the calcium/CaM binding inhibitor W-7 showed no increase in cGMP. The NO donor sodium nitroprusside significantly increased cGMP levels in unstimulated isolated salivary glands. A possible function for NO in salivation by this ixodid tick is discussed.

Sliding dermoid cyst. A case report

Dermoid cysts of the oral cavity usually present as a solitary, painless mass in the midline or, on occasion, more laterally in the submandibular region. A patient is described who presented with a mass in the submandibular region, which could be made to appear or disappear at will. This unusual manifestation occurred as the cyst plunged around the posterior border of the mylohyoid on tensing the floor of the mouth.

Nursing rotas. Shift up

Trusts may wish to consider more flexible, staggered daytime shifts, which accommodate married nurses--for instance, 9.30 am-3.30 pm on weekdays with longer hours at weekends/on nights to ensure that contractual requirements are met. For larger trusts, creche/nursery facilities may solve the problem. After-school clubs on site on a voluntary basis may also mean that more married women and unmarried women with children could more easily accommodate standard shifts. The tribunal decision seems to condone the provision of somewhat ad hoc training and supervision, whereas in professional practice continuous supervision and participation in professional developments are essential elements in the provision of safe, high-quality clinical practice.

Massetolides A-H, antimycobacterial cyclic depsipeptides produced by two pseudomonads isolated from marine habitats

Massetolides A-H (1-8), novel cyclic depsipeptides, and the known compound viscosin (9) have been isolated from cultures of two Pseudomonas sp. isolated from a marine alga and a marine tube worm, respectively. Massetolide A (1) and viscosin (9) exhibit in vitro antimicrobial activity against Mycobacterium tuberculosis and Mycobacterium avium-intracellulare. Precursor-directed biosynthesis has been used to generate unnatural massetolides 11-13 incorporating nonprotein amino acids.

Mutator tRNAs are encoded by the Escherichia coli mutator genes mutA and mutC: a novel pathway for mutagenesis

We have previously described the mutator alleles mutA and mutC, which map at 95 minutes and 42 minutes, respectively, on the Escherichia coli genetic map and which stimulate transversions; the A.T-->T.A and G.C-->T.A substitutions are the most prominent. In this study we show that both mutA and mutC result from changes in the anticodon in one of four copies of the same glycine tRNA, at either the glyV or the glyW locus. This change results in a tRNA that inserts glycine at aspartic acid codons. In view of previous studies of missense suppressor tRNAs, the mistranslation of aspartic acid codons is assumed to occur at approximately 1-2%. We postulate that the mutator tRNA effect is exerted by generating a mutator polymerase and suggest that the epsilon subunit of DNA polymerase, which provides a proofreading function, is the most likely target. The implications of these findings for the contribution of mistranslation to observed spontaneous mutation rates in wild-type strains, as well as other cellular phenomena such as aging, are discussed.

Pathogenesis of gastric metaplasia of the human duodenum: role of Helicobacter pylori, gastric acid, and ulceration

BACKGROUND & AIMS

The pathogenesis of gastric metaplasia (GM) in the duodenum is unclear. The aim of this investigation was to study the effect on the extent of GM of ulcer healing, Helicobacter pylori eradication, and acid suppression singly and in combination. The relationship between GM and gastroduodenal inflammation and H. pylori infection density was also studied.

METHODS

Duodenal and gastric antral biopsy specimens were obtained from H. pylori-positive patients with duodenal ulcer and from H. pylori-positive nonulcer subjects. Biopsy procedures from patients with duodenal ulcer were repeated after 6 months of treatment. Nonulcer subjects were treated symptomatically and did not undergo re-endoscopy.

RESULTS

Ulcer healing alone produced no change in GM or in gastroduodenal inflammation. H. pylori eradication produced a 42% reduction in GM and improvement in inflammation. Acid suppression produced a 43% reduction in GM but without a significant change in inflammation. A combination of H. pylori eradication and acid suppression produced an additive effect with a 66% reduction in GM. A positive relationship was detected between the extent of GM and antral H. pylori density, duodenitis score, and antral gastritis score.

CONCLUSIONS

This study shows that the extent of duodenal GM is unrelated to the presence or absence of ulceration but is partly due to H. pylori and partly due to acid.

Prospective screening of dyspeptic patients by Helicobacter pylori serology

Helicobacter pylori infection is associated with 95% of duodenal ulcers and more than 80% of gastric ulcers. Several reports have indicated that screening for H pylori may avoid subsequent endoscopic examination. We screened 183 dyspeptic patients, aged under 45, by taking a history of sinister symptoms and regular use of non-steroidal anti-inflammatory drugs (NSAIDs), together with serological testing for H pylori. Endoscopy was performed on 113 patients, of whom 90 (49%) were seropositive, 14 (8%) had sinister symptoms, and 9 (5%) had used NSAIDs regularly. In 34 (19%) patients we detected peptic ulceration. The remaining 70 (38%) patients who were H pylori seronegative, had no sinister symptoms, and had not taken NSAIDs (screen-negative), did not undergo endoscopy but were returned to their primary care physician for treatment of symptoms. At subsequent reassessment (of the non-endoscoped group), symptom severity (p = 0.002), interference with life events (p = 0.01), and medication (p = 0.0002) were all significantly lower in the 6 months after screening than in the 6 month period before screening. Only three screen-negative patients were re-referred after screening but their endoscopic findings were normal. Thus, 67 (36%) endoscopies were avoided. When the non-endoscoped screen-negative patients were compared with a cohort of endoscoped screen-negative patients, the groups did not differ in terms of symptom severity (odds ratio 1.12, 95% CI 0.53-2.35, p = 0.77) or interference with life events (0.82, 0.38-1.76, p-0.61). However, medication use was significantly less (0.37, 0.17-0.80, p = 0.01) in those who did not have an endoscopy. Our study indicates that colonisation screening based on H pylori serology, a history of sinister symptoms, or a history of NSAID use was worthwhile in dyspeptic patients. We avoided 37% of endoscopies and reduced drug usage without disadvantaging those not endoscoped.

Neurochemical correlates of the Klüver-Bucy syndrome by in vivo microdialysis in monkey

The Klüver-Bucy syndrome is a well known consequence of lesions of the temporal lobe, but the neural mechanisms remain obscure. To elucidate the neurochemical changes in this syndrome, we utilized in vivo microdialysis of amygdala and hypothalamus in two Cebus monkeys (C. apella) before and after bilateral lesions of the temporal pole (TP). Both subjects were housed and observed in a social group when not being dialyzed. Behavioral changes consequent to the TP lesion included early postoperative anorexia, adipsia, hunched posture, tameness, and lethargy. Subsequently loss of fear, hyperorality, loss of social rank, and social withdrawal were observed. Neurochemical changes in amygdala included fall in DA metabolites, increase in NE, and fall in 5-HIAA. The amino acids glutamate and aspartate were both lower postoperatively but more so in the subject with the greatest behavioral changes. Similar changes were noted in hypothalamus except for DA metabolites which remained unchanged. The Klüver-Bucy syndrome consequent to ablation of the temporal pole appears related to a partial deafferentation of excitatory projections to amygdala, along with a lowering of DA and 5-HIAA and an increase in NE.