Unmet Needs in Functional and Nonfunctional Pancreatic Neuroendocrine Neoplasms

Recently, the European Neuroendocrine Tumor Society (ENETS) held working sessions composed of members of the advisory board and other neuroendocrine neoplasm (NEN) experts to attempt to identify unmet needs in NENs in different locations or with advanced/poorly differentiated NENs. This report briefly summarizes the main proposed areas of unmet needs in patients with functional and nonfunctional pancreatic NENs.

Transplantation of parathyroid tissue in experimental hypoparathyroidism: in vitro and in vivo function of parathyroid tissue microencapsulated with a novel amitogenic alginate

Microencapsulation of tissues is an alternative to postoperative immunosuppression in transplantation. In 1994 iso-, allo- and xenotransplantation of microencapsulated parathyroid tissue was achieved in vivo. However, continued analysis of the coating substance (an alginate) determined mitogenic properties. Here, we report on the in vitro and in vivo function of parathyroid tissue microencapsulated with a novel amitogenic alginate suitable for use in humans. To assess in vitro function, parathyroid tissue encapsulated with mitogenic and amitogenic alginate was exposed to rising concentrations of calcium. For in vivo experiments, it was isotransplanted into parathyroidectomized rats. PTH release into medium and PTH serum levels as well as calcium levels of recipient rats were analyzed and compared to native (non-microencapsulated) tissue and empty capsules, respectively. In vivo, transplants were excised and subjected to histologic examination six months after trans-plantation. In vitro, parathyroid tissue encapsulated with amitogenic alginate releases approximately half of the PTH of native tissue, not different from tissue encapsulated with the mitogenic alginate. In vivo, the novel alginate preserved parathyroid function similar to that of native tissue over the six month period resulting in complete reversal of hypoparathyroidism. Correspondingly, histologic examination revealed vital parathyroid tissue in intact microcapsules. By establishing in vitro function and successful long-term transplantation, we have documented the principle of microencapsulation of parathyroid tissue to be effective also with the novel amitogenic alginate, which is suitable for clinical use.

Medical and Surgical Treatment for Secondary and Tertiary Hyperparathyroidism

Prevention and treatment of secondary hyperparathyroidism (SHPT) in patients on chronic maintenance hemodialysis and of tertiary hyperparathyroidism (THPT) in patients after kidney transplantation is a challenge for the nephrologist and for the surgeon. Indication and results of medical and surgical therapy for SHPT and THPT have remained under discussion during the last decades. This review resumes the current medical and surgical strategies for patients with SHPT and THPT.

Surgical leadership

Still important

Surgery for multiple endocrine neoplasia type 1-associated primary hyperparathyroidism

Background

Surgery in patients with multiple endocrine neoplasia type 1 (MEN1)-associated primary hyperparathyroidism (pHPT) is difficult as the condition it is caused by asymmetrical multiple gland hyperplasia. It is uncertain which operative procedure provides the best outcome with regard to long-term normocalcaemia.

Methods

All patients who had surgery for genetically confirmed MEN1-associated pHPT between 1987 and 2009 were identified from a prospective database. Clinical data, operative procedures and outcome were analysed retrospectively.

Results

A total of 47 patients were identified. Twenty-three patients underwent total parathyroidectomy with thymectomy and autotransplantation (TPTX + AT), 11 patients subtotal parathyroidectomy (3–3·5 glands, SPTX) with thymectomy, and 13 patients selective gland excision (fewer than 3 glands, SGE). Rates of persistent disease, recurrent disease and permanent hypoparathyroidism after TPTX + AT were 4 per cent (1 patient), 4 per cent (1 patient) and 22 per cent (5 patients) respectively. Respective rates after SPTX were 0 per cent, 18 per cent (2 patients) and 45 per cent (5 patients), which were not statistically different from those following TPTX + AT. SGE resulted in persistent disease in 23 per cent (3 patients) and a significantly higher rate of recurrent disease (46 per cent, 6 patients; P = 0·004 versus TPTX, P = 0·210 versus SPTX), but permanent hypoparathyroidism did not occur.

Conclusion

TPTX + AT and SPTX both seem adequate surgical procedures for the treatment of MEN1-associated pHPT and are associated with fewer recurrences than SGE.

[Mesh-wrapping of a traumatised liver with active bleeding: a subsequent complication--obstruction of the inferior vena cava]

In multiply traumatised patients injuries of the -liver are frequently seen. Depending on location and extent of the trauma, different techniques can be applied. In the presented case of a central liver trauma in a 21-year-old man with active bleeding, mesh-wrapping of both liver lobes was applied to achieve control of the bleeding. Postoperatively the patient developed constant hypertension, oliguria and severe anasarka of the lower half of the body caused by a near total obstruction of the inferior vena cava. After removal of the wrappings, all symptoms slowly disappeared. This case and the findings in similar cases in the literature suggest that there is an indication for wrapping a traumatised liver rather with diffuse and peripheral bleeding than with a central liver trauma.

Five years of prospective screening of high-risk individuals from families with familial pancreatic cancer

OBJECTIVE

Familial pancreatic cancer (FPC) accounts for approximately 3% of all pancreatic cancer (PC) cases. It has been suggested that high-risk individuals (HRIs) should be offered a screening programme.

AIM

To evaluate the diagnostic yield of a prospective screening programme in HRIs from families with FPC over a period of 5 years.

METHODS

HRIs of families with FPC of the National German Familial Pancreatic Cancer Registry (FaPaCa) were counselled and enrolled in a prospective, board-approved PC screening programme. Screening included clinical examination, laboratory tests, endoscopic ultrasound (EUS) and MRI with magnetic resonance cholangiopancreaticography (MRCP) and MR angiography.

RESULTS

Between June 2002 and December 2007, 76 HRIs of families with FPC took part in the screening programme with a total of 182 examination visits. Twenty-eight patients revealed abnormalities in EUS (n = 25) and/or MR/MRCP (n = 12). In 7 patients fine needle aspiration cytology was performed. Operative pancreatic explorations were performed in 7 individuals, resulting in limited resections in 6 cases. Histopathological examination of the resected specimens showed serous oligocystic adenomas (n = 3), pancreatic intraepithelial neoplasia 1 (PanIN1) lesions with lobular fibrosis (n = 1), PanIN2 lesions (n = 1) and PanIN1 lesion plus a gastric type intraductal papillary mucinous neoplasm (IPMN) (n = 1).

CONCLUSIONS

In FPC an EUS/MR/MRCP-based screening programme leads to the detection of potential precursor lesions of PC. However, the yield of an extensive screening programme is low, especially since the tumourigenic value of low grade PanIN lesions is not yet defined. Taking into account the enormous psychological stress for the tested individual and the high costs, a general PC screening in HRIs is not justified.

Structured information during the ICU stay to reduce anxiety: study protocol of a multicenter randomized controlled trial

Background

ICU stay is often associated with negative experiences for the individual patient. Many patients are disabled and their communication is restricted during the ICU stay. Specific information on procedures, sensations and coping behavior are thought to reduce anxiety on the ICU. Until now information programs to reduce anxiety were mainly delivered preoperatively, completely neglecting informational needs of non-elective ICU patients.

Methods

The trial is designed as a prospective multicenter randomized controlled trial in the cities of Marburg, Halle and Stuttgart. Elective and non-elective ICU patients will be included. The trial includes an intervention and a control group on the ICU. The control group receives a trivial conversation without any ICU-specific information. The intervention group receives an information program with specific procedural, sensory and coping information about their ICU stay. Both conversations take place in the ICU and are planned to take about 10 minutes.

Discussion

In contrast to former trials on information programs on the ICU-stay our intervention will take place in the ICU itself. This approach will ensure to compensate for memory effects due to anesthesia or preoperative stress. Further the results will be applicable to non-elective ICU-patients.

Trial Registration

ClinicalTrials NCT00764933

Reoperative surgery for primary hyperparathyroidism

Successful in up to 90 per cent of patients

Immunohistochemical studies on specificity and affinity of the BB5-antibody against human parathyroid tissue

Localisation of parathyroid tissue in hyperparathyroidism may be difficult with standard methods. Immunoscintigraphy, using radiolabeled antibodies against epitopes of human parathyroid cells, could be a promising alternative. Therefore, we studied the necessary preconditions, whether the so-called BB5-antibody, directed against parathyroid cell membranes possesses sufficient specificity and affinity to be employed in immunoscintigraphy. Specificity was tested immunohistochemically with APAAP-staining of 39 different human tissues. Additionally, an immunoscore-based quantitative comparison was performed to test the affinity of BB5-antibody for normal and pathologic parathyroid tissue. Specificity was proven by the fact that of all 39 tested tissue-types only the parathyroid tissue was BB5-positive. Normal parathyroid tissue showed a significantly higher affinity to the BB5-antibody than pathologic parathyroid tissue (p < 0.03). However, all tissue samples from primary or secondary hyperparathyroidism exhibited sufficient staining. We conclude that the BB5-antibody fulfills the necessary conditions to be tried for immunoscintigraphical localisation of the parathyroid glands.

Influence of somatostatin to biochemical parameters in patients with primary hyperparathyroidism

Somatostatin (SRIF) is effective in the nonoperative management of a variety endocrine tumors. A potential role of SRIF for treatment of patients with primary hyperparathyroidism (pHPT) has been suggested. In a controlled, prospective, triple-blinded, randomized clinical trial, the somatostatin analogue octreotide (SMS 201-995, Sandostatin) was evaluated in 40 patients with well documented pHPT. Amongst other biochemical parameters, serum calcium and-phosphate and levels of parathyroid hormone, calcitonin, and osteocalcin as well as octreotide were assessed before and for 4 hours after a single iv. application of 200 micrograms ocreotide or placebo. SRIF-receptor autoradiography was performed in parathyroid tissue samples. Baseline values revealed a constellation of biochemical parameters typically found in pHPT. Following 200 micrograms octreotide, no significant changes in any of the biochemical parameters investigated for were observed. Multivariate analysis was performed to identify patient subpopulations in which any given combination of laboratory parameters changed in response to either drug or placebo. However, no 'responders' to octreotide were identified. 45% of patients receiving octreotide, reported side effects. Parathyroid tissue samples were negative for SRIF-receptor expression. It is concluded that a single dose iv. application of octreotide does not result in appreciable changes of biochemical parameters relevant in pHPT and carries a high rate of side effects. Furthermore, absence of SRIF-receptors in parathyroid tissue from patients with pHPT, together with lack of octreotide effects, suggests that somatostatin-analogues may not be effective in the non-operative therapy of pHPT.

The impact of self-belief on laparoscopic performance of novices and experienced surgeons

BACKGROUND

In many professions, nontechnical aspects such as motivation or coping with stress are known to influence performance, success, and outcome. These qualities are assessed and trained in novices for quality and safety reasons. This study explored the impact of self-belief of surgeons on laparoscopic performance using a virtual reality simulator (LapSim).

METHODS

Eighteen inexperienced surgical residents (with less than ten laparoscopic procedures performed) and 22 advanced residents (with more than 50 laparoscopic procedures performed) filled out a ten-item questionnaire used for the assessment of the individual sense of general self-efficacy (GSE). Afterward the participants were asked to perform three defined tasks on the LapSim, each at two different levels of difficulty. The tasks consisted of coordination, dissection, and application of clips. To assess laparoscopic performance, the total time to complete the tasks, economy of motion, and damage parameters were analyzed and correlated with the GSE score by means of Bravis-Pearson correlation analysis.

RESULTS

In novices, high GSE scores correlated with more errors and poor economy of motion, while in advanced residents, laparoscopic performance was independent of the level of assessed self-efficacy.

CONCLUSION

In a small sample, high self-belief does not predict success. In novices it negatively correlates with laparoscopic skills, while in advanced residents it is independent of laparoscopic performance. Thus, training aspects seem to be of greater importance for laparoscopic skills. Nevertheless, nontechnical aspects like self-belief, motivation, stress-coping strategies, judgment, decision-making, and leadership should be included in the surgical curriculum.

Expression of the zinc-finger transcription factor Snail in adrenocortical carcinoma is associated with decreased survival

In this study, we evaluate whether Snail is expressed in adrenocortical cancer (ACC) and if its expression is related to patient outcome. One of the best known functions of the zinc-finger transcription factor Snail is to induce epithelial-to-mesenchymal transition (EMT). Increasing evidence suggests that EMT plays a pivotal role in tumour progression and metastatic spread. Snail and E-cadherin expression were assessed by immunohistochemistry in 26 resected ACCs and real-time quantitative RT–PCR expression analysis was performed. Data were correlated with clinical outcome and in particular with overall patient survival. Seventeen of 26 (65%) ACC tumour samples expressed Snail when assessed by immunohistochemistry. Snail expression was neither detected in normal adrenocortical tissue, nor in benign adrenocortical adenomas. Expression levels were confirmed on the mRNA level by Real-Time–PCR. Survival rates were significantly decreased in Snail-positive tumours compared to Snail-negative tumours: 10 out of 16 vs one out of eight patients succumbed to disease after a median follow up of 14.5 and 28.5 months, respectively (P=0.03). Patients with Snail-expressing ACCs presented in advanced disease (11 out of 12 vs 6 out of 14, P=0.01) and tend to develop distant metastases more frequently than patients with negative staining (7 out of 11 vs two out of eight, P=0.19). In conclusion, we describe for the first time that Snail is expressed in a large subset of ACCs. Furthermore, Snail expression is associated with decreased survival, advanced disease and higher risk of developing distant metastases.

The impact of parathyroid gland autotransplantation during bilateral thyroid surgery for Graves' disease on postoperative hypocalcaemia

OBJECTIVE

The aim of this study was to compare the rate of hypocalcaemia after bilateral thyroid resection for Graves' Disease in patients with and without parathyroid gland autotransplantation (PTAT).

PATIENTS AND METHODS

A total of 153 patients following thyroid surgery for Graves' disease were studied. Patients were divided into three groups. Subgroup I comprised of 129 patients without PTAT, Subgroup II comprised of 19 patients with PTAT of one parathyroid gland and Subgroup III comprised of 6 patients with PTAT of two parathyroid glands. Association between PTAT and postoperative hypocalcaemia (PH) after thyroidectomy was investigated.

RESULTS

There were 27/128 (21.1%) patients with transient and 10/128 (7.8%) patients with permanent hypocalcemia within Subgroup I. Among Subgroup II 4/19 (21.1%) patients developed transient and no patient developed permanent hypocalcaemia, while in Subgroup III 2/6 (33.3 %) patients developed transient hypocalcaemia which became persistent. Thus, the frequency of permanent postthyroidectomy hypocalcaemia (PH) was significantly higher in the Subgroup III with PTAT of two parathyroid glands when compared to the Subgroup I without PTAT (p=0.032) and Subgroup II with PTAT of only one parathyroid glands (p=0.012).

CONCLUSION

PTAT of one parathyroid gland is an effective procedure to reduce the incidence of permanent hypoparathyroidism after bilateral surgery for Graves disease. Transient hypoparathyroidism was not influenced by PTAT.

Open diverticulectomy in a patient with a giant symptomatic retro-pancreatic duodenal diverticulum. A case report

Although often incidentally found, diverticular disease of the small bowel and duodenum may generate complications and impose surgical treatment. Diagnosis of small bowel diverticulosis is difficult because the clinical picture is usually ambiguous. We report a case of diverticulosis of the whole intestine including a giant symptomatic retro-pancreatic duodenal diverticulum in a 74-year-old patient who presented with recurrent episodes of abdominal pain, weight loss and intestinal obstruction. The diagnosis was made by MRI enteroclysis and endoscopy. Open diverticulectomy with choledochostomy and insertion of a T-tube was performed and resulted in a rapid improvement of the symptoms.

Management of sporadic and multiple endocrine neoplasia type 1 gastrinomas

BACKGROUND

Gastrinomas are functional endocrine duodenopancreatic tumours and are responsible for Zollinger-Ellison syndrome (ZES). Clinical presentation, localization techniques and operative management were reviewed.

METHODS

An electronic search of the Medline database was undertaken for articles published in English between January 1987 and May 2007. This timeframe was chosen because of the fundamental changes in operative strategy, antisecretory therapy and localization techniques during this period.

RESULTS AND CONCLUSION

Most gastrinomas are located in the 'gastrinoma triangle', comprising the head of the pancreas, and the first and second parts of the duodenum. Some 20 per cent of gastrinomas occur in association with multiple endocrine neoplasia type 1 (MEN1) and 50-60 per cent of tumours are malignant at the time of diagnosis. Biochemical evidence justifies operation of which duodenotomy is an essential part. Only complete tumour resection allows 5- and 10-year survival rates of 90 per cent. Pylorus-preserving pancreaticoduodenectomy may be the procedure of choice for MEN1-ZES.

Developing Effective Screening Strategies in Multiple Endocrine Neoplasia Type 1 (MEN 1) on the Basis of Clinical and Sequencing Data of German Patients with MEN 1

BACKGROUND

Multiple-endocrine-neoplasia-type-1 (MEN1) is an autosomal-dominant inherited disorder characterized by the combined occurrence of primary hyperparathyroidism (pHPT), gastroenteropancreatic neuroendocrine tumors (GEP), adenomas of the pituitary gland (APA), adrenal cortical tumors (ADR) and other tumors. As the tumors appear in an unpredictable schedule, uncertainty about screening programs is persisting.

OBJECTIVE

To optimize screening and to analyze possible differences in sporadic versus familial cases.

METHODS

We analyzed data of 419 individuals including 306 MEN-1 patients (138 isolated and168 familial cases out of 102 unrelated families).

RESULTS

A total of 683 tumors occurred consisting of 273 pHPT, 138 APA, 166 GEP, 57 ADR, 24 thymic- and bronchial-carcinoids as well as 25 neoplasms of other tissues. The age-related penetrance was determined as 10%, 35%, 67%, 81% and 100% at 20, 30, 40, 50 and 65 years respectively. Although pHPT being the most frequent first manifestation (41%), also GEP (22%) or APA (21%) were found to be the first presentation. APA occurred significantly more frequent (p<0,05) in isolated (n=138) than in familial (n=168) cases, whereas GEP showed a tendency to occur more often in familial cases. Genotype/phenotype correlation in 140 clinically affected MEN-1 cases showed a tendency for truncating mutations, especially nonsense mutations to be associated to GEP and carcinoids of the lungs and thymus.

CONCLUSION

In view of the morbidity and frequency in familial cases an effective screening programme should aim at an early diagnosis of GEP particularly when truncating, especially nonsense mutations are found.

Surgical Treatment of Tertiary Hyperparathyroidism: The Choice of Procedure Matters!

BACKGROUND

Parathyroid surgery (PTX) in patients with tertiary hyperparathyroidism (tHPT) may endanger the long-term survival of transplanted renal grafts. The mechanism by which graft function deteriorates is unknown. We reviewed our experience in regard to the operative procedures and postoperative outcome.

METHODS

Sixty-nine patients were operated on for tHPT between 1987 and 2006 at our institution. Serum (s) calcium, s-creatinine, and levels of intact parathyroid hormone (PTH) were measured before and after PTX. The Modification of Diet in Renal Disease (MDRD) equation was used to estimate glomerular filtration rate (GFR).

RESULTS

The entire patient group developed a deterioration of kidney graft function after PTX. Nineteen of 69 patients developed a decrease in GFR of more than 20% during the hospital stay, persisting for more than one year after PTX. Ten of them had to restart dialysis during the first year after PTX. Mean preoperative s-creatinine was 4.4 +/- 0.6 mg/dl in these patients. When divided according to the surgical procedure performed, only the subgroup who underwent total parathyroidectomy showed a significant worsening of graft function when compared to subtotal or reoperative PTX.

CONCLUSIONS

PTX is an efficient way to treat tHPT but represents a risk for impairing graft function, especially for patients that already demonstrate poor kidney function at the time of surgery. In the aim to prevent transient hypoparathyroidism, which may provoke reduced graft perfusion, as one possible cause of kidney graft deterioration associated with PTX, one should consider subtotal instead of total parathyroidectomy.

[Adrenal incidentalomas]

Adrenal incidentalomas are clinically inapparent masses detected incidentally with imaging studies conducted for other reasons. They are relatively common and require structured diagnostic workup. In many cases surveillance is warranted. The diagnostic workflow has to reveal whether the mass is hormonally functioning and/or if there is evidence of malignancy. If the tumor is functionally silent and not larger than 4 cm, surveillance is warranted. Functioning tumors and masses larger than 6 cm have to be resected. Fine-needle aspiration biopsy is indicated in very rare cases, but pheochromocytoma has to be ruled out first.

Spatial perception predicts laparoscopic skills on virtual reality laparoscopy simulator

OBJECTS

This study evaluates the influence of visual-spatial perception on laparoscopic performance of novices with a virtual reality simulator (LapSim(R)).

MATERIALS AND METHODS

Twenty-four novices completed standardized tests of visual-spatial perception (Lameris Toegepaste Natuurwetenschappelijk Onderzoek [TNO] Test(R) and Stumpf-Fay Cube Perspectives Test(R)) and laparoscopic skills were assessed objectively, while performing 1-h practice sessions on the LapSim(R), comprising of coordination, cutting, and clip application tasks. Outcome variables included time to complete the tasks, economy of motion as well as total error scores, respectively.

RESULTS

The degree of visual-spatial perception correlated significantly with laparoscopic performance on the LapSim(R) scores. Participants with a high degree of spatial perception (Group A) performed the tasks faster than those (Group B) who had a low degree of spatial perception (p = 0.001). Individuals with a high degree of spatial perception also scored better for economy of motion (p = 0.021), tissue damage (p = 0.009), and total error (p = 0.007).

CONCLUSION

Among novices, visual-spatial perception is associated with manual skills performed on a virtual reality simulator. This result may be important for educators to develop adequate training programs that can be individually adapted.

Comparison of Minimally Invasive Surgical Skills of Neurosurgeons versus General Surgeons: Is there a Difference in the First Exposure to a Virtual Reality Simulator?

OBJECTIVE

The increasing use of minimally invasive surgery, which has a longer learning curve compared to open surgery lets the necessity to develop training programs to improve endoscopic skills of trainees become ever clearer. The aim of this study was to compare the endoscopic skills of neurosurgeons versus general surgeons at first exposure to a virtual reality simulator.

METHODS

72 general surgeons who visited the 122nd Conference of the German Surgeons Society (DGCH in Munich 2005) and 35 neuroendoscopic surgeons, who visited the Third World Conference of the International Study Group of Neuroendoscopy (ISGNE in Marburg 2005) participated in this study. Each participant performed the basic module "clip application" on the virtual reality simulator (LapSim). All participants were given the same pretest instructions. Time to complete the task, error score and economy of motion were recorded.

RESULTS

The general surgeons performed the clip application faster, but with more errors than neuroendoscopic surgeons. However, the difference of both parameters was not significant. Both surgeon groups have a similar score for economy of motion.

CONCLUSION

Although neuroendoscopic surgeons were exposed to a foreign procedure and unfamiliar equipment, they were able to perform virtual endoscopy with similar accuracy as general surgeons, who are adapted to these endoscopic instruments and procedures and do these daily.

Differential effects of cetuximab and AEE 788 on epidermal growth factor receptor (EGF-R) and vascular endothelial growth factor receptor (VEGF-R) in thyroid cancer cell lines

This study evaluated the role of EGF and the effects of EGF-targeting drugs (Cetuximab, AEE 788) on growth, apoptosis, and autocrine VEGF-secretion of thyroid cancer (TC) cells. Autocrine activation of the epidermal growth factor receptor (EGF-R) is commonly regarded to contribute to the malignant phenotype of TC cells and may therefore represent a rational therapeutic target. Out of a number of TC cell lines two anaplastic (Hth74, C643), one follicular (FTC133), and one papillary thyroid cancer cell line (TPC1) were analyzed in depth for VEGF-R-and EGF-R-expression, basal and EGF-stimulated (1-100 ng/ml) VEGF protein secretion and proliferation. Subsequently the antiprolifereative and antiangiogenic effect of cetuximab (Erbitux), a monoclonal antibody that blocks the EGF-R and AEE 788, a novel dual-kinase inhibitor of EGF-R and VEGF-R were assessed, and the downstream EGF-R signal transduction was analyzed by means of detecting phosphorylated pEGF-R, pVEGF-R, pAkt, and p-MAPK. EGF stimulated VEGF-mRNA expression and protein secretion in all TC cell lines. The EGF-R antagonist Cetuximab consistently decreased VEGF secretion in all TC cell lines (min. 15%, n.s. in C643 cells and max. 90% in Hth74 cells, P < 0.05), but did not affect tumor cell proliferation in vitro. In contrast, the EGF-R- and VEGF-R-kinase inhibitor AEE 788 not only reduced VEGF secretion (min. 55%, P < 0.05 in C643 and max. 75%, P < 0.05, in FTC133), but also exhibited a dose-dependent inhibition of tumor cell proliferation (min. 75%, P < 0.05 in C643 and max. 95%, P < 0.05 in Hth74) and was a potent inductor of apoptosis in two of four TC cell lines. These effects were always accompanied by reduced levels of pEGF-R, pVEGF-R, pAkt, and pMAPK. Although inhibition of the EGF-receptor by Cetuximab potently disrupts autocrine secretion of VEGF, only the concurrent inhibition of the VEGF- and EGF receptor, e.g., by AEE 788 induces reduced proliferation and apoptosis in vitro. This suggests a particular rationale for the use of tyrosine kinase inhibitors with dual modes of action such as AEE 788 in thyroid cancer.

[Operative management and long-term survival in patients with neuroendocrine tumors of the pancreas--experience with 144 patients]

BACKGROUND AND OBJECTIVE

To evaluate the outcome of patients with pancreatic endocrine tumors (PETs) in a tertiary referral centre.

METHODS

144 patients with PETs that underwent surgery between 1987 and 2005 at our institution were retrospectively evaluated. The diagnosis of gastrinoma, insulinoma, vipoma and non-functioning PETs was based on clinical symptoms, biochemical tests and histopathology.

RESULTS

144 patients were identified for this study, 20% with a MEN1-syndrome. 172 operations were performed, 122 initial operations and 50 reoperations. Enucleation of the tumor and distal pancreatic resections were the main type of operations. In 23 patients liver metastases were resected. After a median follow up of 67 months (range 1-339), 74 of 144 (51%) patients are still alive without evidence of disease. No patient with a benign tumor and no MEN1-patients died because of PETs. The 5, 10, and actuarial 20-year survival rate for patients with malignant tumors were 75%, 70% and 65%, respectively. The survival rate was significantly related to the type of tumor (benign vs. malignant: p = 0.0002), the patients age at time of initial operation (<50 years vs. >50 years: p = 0.0007), the genetic background of the tumor (sporadic vs. MEN1: p = 0.0312) and the development of metastases after the initial operation (none or lymph node metastases vs. distant metastases: p = 0.01).

CONCLUSION

We show that an aggressive surgical approach leads to cure in patients with benign PETs. Although long-term cure can only be achieved in a proportion of patients with malignant PETs, significant long-term palliation can be achieved.

[Instituting a surgical skills lab at a training hospital]

The improvement of surgical skills of trainees in Germany often occurs solely in the operating room. In recent years, several countries have established surgical skills labs as an essential part of surgical education, with the goal of improving and refining surgical skills before clinical application. Several years ago, training units were established by the industry wherein the curricula focused on products of the respective company. Selected training courses are still offered in a few clinics. Presently, laboratories which train the surgical skills of novices in an individually adapted form are lacking. A surgical skills lab with a comprehensive curriculum of training courses was introduced at the University Hospital of Marburg in 2005. The present article describes the development and introduction of such facilities. The authors are convinced that surgical skills labs will become increasingly important in German surgical education for improving patient safety in the operating room.

Adrenal involvement in multiple endocrine neoplasia type 1: results of 7 years prospective screening

BACKGROUND

Adrenal tumors are a common manifestation of the multiple endocrine neoplasia type 1 (MEN-1) syndrome. Prevalence in recent studies varies between 9 and 45%. A genotype-phenotype correlation has been described as well as the development of adrenocortical carcinomas. Long-term prospective data are still lacking.

MATERIALS AND METHODS

Thirty-eight MEN-1 patients with proven germline mutations have been prospectively observed in a regular screening program in our hospital. Adrenal glands have been screened by biochemical analysis and either by endoscopic ultrasound (EUS) or computed tomography (CT) or both. Median follow-up was 48 months (12-108 months). Age at diagnosis of MEN-1, type of adrenal tumor, genotype, therapy, and clinical characteristics have been analyzed.

RESULTS

In 21 (55%) patients, adrenal involvement of the disease was detected. Adrenal lesions were detected in average 6.9 years after the initial diagnosis of MEN-1. Median tumor size was 12 mm (5-40 mm). Tumor size smaller than 10 mm was observed in 11 patients. Twelve patients had unilateral while nine had bilateral adrenal lesions. EUS detected all adrenal tumors, whereas CT failed in seven cases. In three patients, functioning tumors (one pheochromocytoma, one bilateral Cushing adenoma, and one adrenocortical carcinoma) and one nonfunctioning adenoma were diagnosed by histology and biochemical assessment. Two laparoscopic adrenalectomies and one laparoscopic subtotal resection were performed. Nonfunctioning adrenal lesions, not characterized by histology yet, were found in 18 patients. There was no statistical difference with regard to adrenal involvement between patients with germline mutations in exons 2 and 10 (12/21) and those with mutations in exons 3-9 (6/11).

CONCLUSION

MEN-1-associated adrenal tumors are mostly small, benign, and nonfunctioning and much more common than previously reported. EUS was the most sensitive imaging procedure. The genotype-pheotype correlation previously suggested by our group could not be confirmed.

Negative stress-coping strategies among novices in surgery correlate with poor virtual laparoscopic performance

Background

This study explored the impact of habitual stress-coping strategies on the laparoscopic performance of novices in surgery using a virtual reality simulator.

Methods

The SVF78 stress-coping questionnaire was administered to 12 medical students in their final year of medical school (camera holders) and to 12 inexperienced surgical residents (postgraduate years 1–3). The questionnaire included devaluation during stressful situations, distractions from stressful situations, control over stressful reactions and negative coping strategies such as stress avoidance and need for social support. Assessment of laparoscopic dexterity was based on the results of performance on a virtual reality simulator. The variables of time taken to complete the task, errors and economy of motion were analysed, with a higher score indicating poor performance. Pearson and non-parametric Spearman correlations were used to compare the subjects' results on the SVF78 with those on the LapSim®.

Results

Time taken to complete the task correlated with high values in distractive stress-coping strategies (P = 0·002) and high values in negative stress-coping strategies (P = 0·042).

Conclusion

Ineffective stress-coping strategies correlate with poor virtual laparoscopic performance. The need for effective intraoperative stress-coping strategies is evident.

Targeting the EGF/VEGF-R system by tyrosine-kinase inhibitors--a novel antiproliferative/antiangiogenic strategy in thyroid cancer

AIM

In thyroid cancer (TC), endothelial growth factor (EGF) has been associated with dedifferentiation, tumor cell proliferation, and angiogenesis. Vascular endothelial growth factor (VEGF) has been documented to be the main stimulator of angiogenesis in the thyroid gland. Patients with undifferentiated thyroid cancer are in desperate need of new therapeutic strategies because common protocols of therapy usually fail. The aim of this study, therefore, was to evaluate two tyrosine-kinase inhibitors (TKI, ZD 1839 gefitinib and ZD 6474 vandetanib), directed against the EGF/VEGF receptor for possible antitumor therapy in thyroid cancer.

METHODS

EGF/VEGF-R was documented in anaplastic (Hth74, C643), follicular (FTC133), and papillary (TPC1) thyroid cancer cell lines by Western blot analysis. The antiproliferative effect of two TKI (0.1-10 microM) on thyroid cancer cell lines in vitro was quantified by MTT assay, the antiangiogenic effect by assessing secretion of VEGF by enzyme-linked immunosorbent assay (R&D Systems). ZD 1839 is mainly directed against EGF-R and ZD 6474 against VEGF-R (AstraZeneca, UK), single applications and combinations of compounds were evaluated.

RESULTS

EGF-R and VEGF-R as well as the phosphorylated receptor were documented in all of the cell lines. Administration of ZD1839 led to an up to 90% reduction of cell number in Hth74, 80% in C643, 50% in FTC133, and 90% in TPC1 (p < 0.05). ZD1839 induced a decrease of VEGF secretion between 30% in C643 and 90% in Hth74. Administration of ZD6474 led to an up to 95% reduction of cell number in Hth74, 85% in C643, 90% in FTC133, and 90% in TPC1 (p < 0.05). The ZD6474 induced decrease of VEGF secretion ranged between 20% (FTC133) and 60% (TPC1). Combinations of IC50 concentrations of TKI showed synergistic effects, resulting in additional inhibition of proliferation between 50 and 90% compared to single drug administration.

CONCLUSION

The EGF/EGF-R system resembles a powerful VEGF-stimulating pathway in all histiotypes of TC and can be inhibited by TKI. TKI directed against EGF-R as well as VEGF-R inhibit tumor cell proliferation and VEGF secretion in vitro. Combinations of TKI are more effective than strategies using single agents. It is suggested that targeting EGF-R/VEGF-R-mediated pathways may have therapeutic potential in some undifferentiated thyroid cancers.

Clinical background is required for optimum performance with a VR laparoscopy simulator

OBJECTIVE

To determine the role of clinical background when assessing the learning effect using a virtual-reality (VR) laparoscopy simulator (LapSim).

MATERIALS AND METHODS

Test subjects were 12 final-year medical students (Group A) and 12 inexperienced residents (Group B) with no previous experience of VR simulators. First, to establish a baseline, both groups performed the "clip application" task twice. They then completed a training program of increasing difficulty (coordination, cutting and clip application), after which both groups were re-tested using a difficult level of the "cutting" task as an endpoint measurement. Time to complete the tasks, as well as trauma and precision parameters, were scored.

RESULTS

Before training, times to complete the baseline task, as well as parameters of trauma and precision, were similar for both groups. After training, Group B (residents) completed the cutting task significantly faster than Group A (students). However, the former group also showed significant improvement in trauma and precision parameter scores in the endpoint measurement.

CONCLUSION

These results suggest that clinical background and understanding of the clinical value of a training program lead to faster acquisition and improvement of laparoscopic skills as performed on the laparoscopy simulator. Thus, medical students or other personnel not involved in practical surgery may be unsuitable as candidates for assessing the value of a VR training program.

Endoscopic ultrasound imaging of insulinomas: limitations and clinical relevance

Compared to other imaging methods, endoscopic ultrasound is the best procedure to localize insulinomas preoperatively. Positive finding furthermore confirms endocrinological diagnosis, especially considering the differential diagnosis of hypoglycaemia factitia by oral antidiabetics. However, it always has to be considered that endoscopic ultrasound imaging may reveal false positive and false negative results, and quality of the findings obtained by endoscopic ultrasound imaging depends to a large extent on the examiner's experience. An important issue of endoscopic ultrasound imaging in insulinomas nowadays is planning surgical strategy. As illustrated by three cases, endoscopic ultrasound imaging enables to identify patients that qualify for laparoscopic, minimal invasive surgery.

Prophylaktische Chirurgie des Pankreas

The goal of prophylactic surgery is to prevent malignant growth in patients with hereditary tumor predisposition. The pancreas presents as particularly challenging, due to the difficulty of operation and comparatively high risk of morbidity and even mortality. In addition, partial operative procedures and, more significantly, total resection lead to exocrine pancreas insufficiency and secondary diabetes, with grave consequences for the patient. Hereditary tumor predisposition syndromes that can result in pancreaticoduodenal endocrine tumors (PET) include multiple endocrine neoplasia type 1 syndrome and von Hippel-Lindau syndrome. As penetrance is maximally 70-80% and the 10-year survival rate over 80%, prophylactic pancreatic resection without evidence of a tumor is not indicated. However, prophylactic extension of a resection would be advised, should a PET be diagnosed. Patients predisposed to developing ductal pancreatic carcinoma (PC) are at risk of familial pancreatic cancer syndrome (FPC), hereditary pancreatitis, and other hereditary tumor predisposition syndromes such as Peutz-Jeghers syndrome and familial atypical multiple mole-melanoma syndrome. As the gene defect responsible for FPC has yet to be identified and the penetrance of PC in the other tumor predisposition syndromes is low or unknown, a prophylactic pancreatectomy based on today's knowledge is not indicated. Prophylactic extension of the resection is advisable should PC or high-grade PanIN lesions be diagnosed, as these patients often present with multifocal dysplasia and even carcinoma.