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D Oertli

Publications and source records attributed to D Oertli.

At least 19 recordsLinked to original sources
PubMed2007

Randomized clinical trial of Lichtenstein's operation versus mesh plug for inguinal hernia repair.

BACKGROUND: Two of the most commonly used open prosthetic tension-free techniques for inguinal hernia repair are Lichtenstein's operation and the mesh plug repair. The technique of choice remains a subject of ongoing debate. The objective of the present investigation was to compare the two surgical procedures with respect to associated morbidity and recurrence rates. METHODS: Five hundred and ninety-five patients with 700 primary or recurrent inguinal hernias were randomized to undergo either Lichtenstein's operation or mesh plug repair. The primary endpoint of the investigation was the recurrence rate 1 year after surgery. Secondary endpoints were perioperative complications and reoperation rates. RESULTS: At 12-month follow-up, 597 hernia repairs (85.3 per cent) were evaluated. There were no significant differences regarding recurrence rates and perioperative complications. However, there was a significant difference in the overall reoperation rate between the two treatment groups, with 13 reoperations (4.2 per cent) in the Lichtenstein group and four (1.4 per cent) in the mesh plug group (P = 0.047). CONCLUSION: Lichtenstein's operation and the mesh plug repair are comparable with respect to perioperative complications and recurrence rates.

Adult↗
PubMed2006

Can skills assessment on a virtual reality trainer predict a surgical trainee's talent in laparoscopic surgery?

BACKGROUND: A number of studies have investigated several aspects of feasibility and validity of performance assessments with virtual reality surgical simulators. However, the validity of performance assessments is limited by the reliability of such measurements, and some issues of reliability still need to be addressed. This study aimed to evaluate the hypothesis that test subjects show logarithmic performance curves on repetitive trials for a component task of laparoscopic cholecystectomy on a virtual reality simulator, and that interindividual differences in performance after considerable training are significant. According to kinesiologic theory, logarithmic performance curves are expected and an individual's learning capacity for a specific task can be extrapolated, allowing quantification of a person's innate ability to develop task-specific skills. METHODS: In this study, 20 medical students at the University of Basel Medical School performed five trials of a standardized task on the LS 500 virtual reality simulator for laparoscopic surgery. Task completion time, number of errors, economy of instrument movements, and maximum speed of instrument movements were measured. RESULTS: The hypothesis was confirmed by the fact that the performance curves for some of the simulator measurements were very close to logarithmic curves, and there were significant interindividual differences in performance at the end of the repetitive trials. CONCLUSIONS: Assessment of perceptual motor skills and the innate ability of an individual with no prior experience in laparoscopic surgery to develop such skills using the LS 500 VR surgical simulator is feasible and reliable.

Adult↗
PubMed2006

[Sonography of the thyroid].

According to its superficial anatomical location the thyroid gland is easily accessible by sonography. Ultrasound is a reliable examination to detect various pathologies of the thyroid gland and it should always be combined with a sonography of the surrounding soft tissues and vessels. Sonography allows an exact documentation of the size, volume and parenchymal echostructure of the thyroid gland as well as detection of various diffuse and focal abnormalities of the gland itself and of the surrounding structures. The presented article gives an overview of the sonographic diagnoses and differential diagnoses of various diffuse and focal pathologies of the thyroid gland as well as some recommendations regarding their possible further diagnostic approach.

Acute Disease↗
PubMed2006

Propensity scores and the surgeon.

BACKGROUND: Evidence-based surgery has been established as a cornerstone of good clinical practice, promising to improve the treatment of patients and the quality of surgical education. However, evidence-based surgery requires dedicated clinicians trained to perform methodologically sound clinical investigations. Statistical knowledge is therefore invaluable. Surgical studies often cannot be randomized. Propensity scores offer a powerful alternative to multivariable analysis in the assessment of observational, non-randomized surgical studies. Unfortunately, many surgeons are unaware of this important analytical approach that has gained increasing stature in medical research. Thus, propensity score analyses are not used often in surgical studies. OBJECTIVE: The purpose of this paper is to provide a comprehensive overview of propensity score analysis, allowing the surgeon to understand the role, advantages and limitations of propensity scores, boosting their development in surgical investigations.

Confounding Factors, Epidemiologic↗
PubMed2005

Presymptomatic thyroidectomy in multiple endocrine neoplasia 2a.

AIMS: To evaluate the value of prophylactic total thyroidectomy in multiple endocrine neoplasia 2a (MEN 2a), based on results of genetic testing, in a presymptomatic early stage of the disease. METHODS: Fourteen presymptomatic patients genetically diagnosed and surgically treated at our centre. We analysed age, gender, location of the RET mutation, calcitonin tests, surgery, histologic findings, TNM classification, and postoperative follow-up. RESULTS: The 14 patients belonged to two families with MTC (MEN 2a). Median age was 16 years. The RET mutation was located in codon 618 and 634. Basal calcitonin (CT) levels were normal in all patients. Twelve had pathologic peak CT measurements. Total thyroidectomy was performed in all and associated central neck dissection in 12 patients. Pathohistologic assessment showed C-cell hyperplasia in all specimens and 11 MTCs; the median size of the tumours was 0.2 cm; two patient had lymph-node metastases. According to TNM, three had stage 0, nine had stage I, one had stage II, and one had stage III disease. Postsurgery basal and peak CT values were normal in all but one patients, indicating a biochemical curative rate of 95%. Calcitonin determination did not distinguish between MTC and C-cell hyperplasia. CONCLUSION: Prophylactic thyroidectomy based on genetic testing allows identification and treatment of patients at an early stage of the disease. Pathologic peak CT values are markers for the presence of microscopic MTC and should be considered in selecting operative procedures for these patients.

Adolescent↗
PubMed2005

[Injection site abscesses in intravenous drug users. Frequency of associated complications related to localisation].

BACKGROUND: Skin and soft tissue infections are the most frequent cause of hospital admissions among intravenous drug users. Associated complications include septic arthritis, septic thrombosis and embolisation, peripheral ischaemia due to intra-arterial injections, venous and arterial pseudoaneurysms, local destruction of adjacent structures, and necrotising fasciitis. METHODS: We conducted a retrospective review of the associated complications of 85 patients with 130 abscesses treated during 108 hospital stays. RESULTS: The majority of abscesses (55%) were located on the lower extremities, where the complication rate following injections was significantly higher than in other parts of the body (12/71 vs 0/55, P=0.0005). Patients with abscesses on the lower extremities had significantly longer hospital stay than those with abscesses on other localisations (8.5 days vs 4.2 days, P=0.0005) and therefore were more expensive to treat. CONCLUSIONS: Surgeons treating abscesses caused by intravenous drug use must be aware of the higher rate of associated complications after injection in the lower extremities. Prevention in drug addiction programs could reduce complications and costs related to drug use by avoiding injection sites on the lower extremities.

Abscess↗
PubMed2005

Long-term outcomes of breast cancer patients after endoscopic axillary lymph node dissection: a prospective analysis of 52 patients.

BACKGROUND: Reports on long-term outcomes after endoscopic axillary lymph node dissection (ALND) of breast cancer patients are still lacking in the medical literature. The objective of this prospective study was to assess the oncological and functional outcomes in breast cancer patients after endoscopic ALND. METHODS: Fifty-five breast cancer patients were prospectively enrolled, of whom 52 were available for follow-up with a median of 71.9 months (range 11-96). The following oncological and functional endpoints were evaluated during follow-up at several time points: occurrence of local, axillary and distant metastases, seroma or infection, shoulder mobility (range of motion), numbness, pain, presence of lymphoedema as well as restriction in activities of daily living. RESULTS: In 52 patients endoscopic ALND of level I and II was successfully performed. Two port-site metastases (2/52, 4%) occurred, one of which in a patient with negative axillary lymph nodes. The same patient suffered from the only axillary recurrence (1/52, 2%). Three patients (3/52, 6%) developed lymphoedema. No other functional adverse events (shoulder mobility, pain, numbness, hypertrophic scar) were noticed at the end of the observation period. CONCLUSION: The present investigation with long-term follow-up after endoscopic ALND--the first one in the literature--reveals minor morbidity, good functional and cosmetic results. In contrary to conventional surgery, the endoscopic procedure is associated with the occurrence of port-site metastases, not seen in the open approach. Axillary recurrences do not appear more frequently when compared with results after conventional ALND. In the meantime the less invasive sentinel lymph node (SLN) biopsy is the established standard technique in evaluating the axillary lymph node status.

Activities of Daily Living↗
PubMed2005

[Current concepts in minimal invasive endocrine surgery].

During the past ten years, endoscopic adrenalectomy has emerged as the standard of treatment of benign diseases of the adrenal gland. Although no randomised trial exists comparing open with endoscopic adrenalectomy, the endoscopic approach has proven to be safe with lower morbidity and shorter hospital stay compared with open surgery. For parathyroidectomy several different minimal invasive techniques have been described (i.e. fully endoscopic, videoscopic assisted, and focused using mini-incision). Prerequisits for all of these approaches are a positive preoperative localisation of the adenoma, an intraoperative parathormone testing, and the respective surgical experience in the minimal invasive technique. Proponents of the videoendoscopic assisted thyroidectomy mention the enhanced exposure of the surgical field to be beneficial. However, drawbacks of this technique are the fact that a minority of patients qualify for this approach and that the learning curve is quite long for the surgeon. The experience with the laparoscopic approach to endocrine pancreatic tumours is still limited. Good indications are insulinomas that are located anteriorly or within the tail of the pancreatic gland. Nowadays, laparoscopic enucleation of such tumours and tail resections become feasable and safe.

Adenoma↗
PubMed2004

Encapsulation into sterically stabilised liposomes enhances the immunogenicity of melanoma-associated Melan-A/MART-1 epitopes.

Tumour-associated antigens (TAA)-specific vaccination requires highly immunogenic reagents capable of inducing cytotoxic T cells (CTL). Soluble peptides are currently used in clinical applications despite an acknowledged poor immunogenicity. Encapsulation into liposomes has been suggested to improve the immunogenicity of discrete antigen formulations. We comparatively evaluated the capacity of HLA-A2.1 restricted Melan-A/MART-1 epitopes in soluble form (S) or following inclusion into sterically stabilised liposomes (SSL) to be recognised by specific CTL, to stimulate their proliferation and to induce them in healthy donors' peripheral blood mononuclear cells (PBMC), as well as in melanoma-derived tumour-infiltrating lymphocytes (TIL). HLA-A2.1(+), Melan-A/MART-1-NA-8 melanoma cells served as targets of specific CTL in 51Cr release assays upon pulsing by untreated or human plasma-treated soluble or SSL-encapsulated Melan-A/MART-1 27-35 (M27-35) or 26-35 (M26-35) epitopes. These reagents were also used to stimulate CTL proliferation, measured as 3H-thymidine incorporation, in the presence of immature dendritic cells (iDC), as antigen-presenting cells (APC). Induction of specific CTL upon stimulation with soluble or SSL-encapsulated peptides was attempted in healthy donors' PBMC or melanoma-derived TIL, and monitored by 51Cr release assays and tetramer staining. Na-8 cells pulsing with SSL M27-35 resulted in a five-fold more effective killing by specific CTL as compared with equal amounts of S M27-35. Encapsulation into SSL also provided a partial (50%) protection of M27-35 from plasma hydrolysis. No specific advantages regarding M26-35 were detectable in these assays. However, at low epitope concentrations (</=100 ng ml(-1)), SSL M26-35 was significantly more effective in inducing CTL proliferation than S M26-35, in the presence of iDC, as APC. Preincubation with iDC for 6 h virtually abolished the capacity of S M26-35 to stimulate specific CTL proliferation, but only partially affected that of SSL M26-35. Most importantly, SSL M26-35 was able to enhance the induction of specific CTL in healthy donors PBMC and in melanoma-derived TIL as compared to S M26-35. Taken together, our data indicate that encapsulation of TAA epitopes into SSL results in effective immunogenic formulations suitable for clinical use in active specific tumour immunotherapy.

Antigens, Neoplasm↗
PubMed2003

Phase I/II clinical trial of a nonreplicative vaccinia virus expressing multiple HLA-A0201-restricted tumor-associated epitopes and costimulatory molecules in metastatic melanoma patients.

We performed a phase I/II clinical trial in metastatic melanoma patients with an ultraviolet (UV)-inactivated nonreplicating recombinant vaccinia virus enabling the expression, from a single construct, of endoplasmic reticulum-targeted HLA-A0201-restricted Melan-A/MART-1(27-35), gp100(280-288), and tyrosinase(1-9) epitopes, together with CD80 and CD86 costimulatory proteins. Corresponding soluble peptides were used to boost responses and granulocyte-macrophage colony-stimulating factor was used as systemic adjuvant. Safety and immunogenicity, as monitored with in vitro-restimulated peripheral blood mononuclear cells by cytotoxic T lymphocyte precursor (CTLp) frequency analysis and tetramer staining, were specifically addressed. Of 20 patients entering the protocol, 2 had to withdraw because of rapidly progressing disease. Immune responses were evaluated in 18 patients (stage III, n = 5; stage IV, n = 13) and increases in specific CTLp frequencies were observed in 15. In 16 patients responsiveness against all 3 antigens could be analyzed: 7 (43%), including all stage III cases, showed evidence of induction of CTLs specific for the three epitopes, and 2 (12%) and 4 (25%), respectively, showed reactivity against two or one tumor-associated antigen. In three stage IV patients no specific CTL reactivity could be induced. Increases in CTLp frequency were detected mostly after viral vaccine injections. However, in a majority of patients final CTLp levels were comparable to initial levels. Tetramer characterization of Melan-A/MART-1(27-35)-specific CTLs during the protocol also suggested preferential expansion after recombinant virus administration. Vector-specific humoral responses, frequently undetectable in stage IV patients, did not appear to prevent tumor-associated antigen-specific CTL induction. Aside from a single occurrence of transient grade 3 leukopenia, no major clinical toxicity was reported. Seventeen of 18 patients completed the 3-month trial (one patient died before the last delayed-type hypersensitivity test). Three displayed regression of individual metastases, seven had stable disease, and progressive disease was observed in seven patients. This is the first report on the administration of a UV-inactivated recombinant vaccinia virus coexpressing five transgenes in cancer patients. The results described here, in terms of safety and immunogenicity, support the use of this reagent in active specific immunotherapy.

Adult↗
PubMed2003

Peritoneal mesothelioma after environmental asbestos exposure.

Mesothelioma are primary malignant neoplasms of the serous membranes. They usually involve the pleura and rarely the pericardium, the peritoneum and the tunica vaginalis testis. About 90% are associated with exposure to asbestos. The exposure is generally occupational, an environmental inhalation of asbestos and asbestiform fibers in areas in Turkey has been observed and presents a major health problem. This report of a patient from Anatolia with peritoneal mesothelioma after environmental exposure outlines the importance of considering this pathology in the differential diagnosis of a Turkish patient presenting with ascites.

Adult↗
PubMed2001

[Neurogenic appendicopathy: a frequent, almost unknown disease picture. Evaluation of 816 appendices and review of the literature].

BACKGROUND: Neurogenic appendicopathy (NA) represents an almost unknown pathology which clinically cannot be differentiated from acute appendicitis. The diagnosis can only be established histologically. Nerve proliferation and an increased number of endocrine cells are typical for NA. This study characterizes the epidemiology, histology, clinical appearance and therapy of NA. We evaluated the incidence of NA in macroscopically normal specimens from patients presenting the symptoms of acute appendicitis and in incidental appendectomies. PATIENTS AND METHODS: 816 routine appendix specimens were examined at the Institute of Pathology, University of Basel, for the presence of NA. We analyzed the indication for appendectomy, the histological form and the age and sex of the patients. RESULTS: 140 appendices (17.1%) showed the histological criteria for NA. 25% of incidental appendectomies were positive for NA, as opposed to 53% of the macroscopically normal specimens of patients presenting the symptoms of acute appendicitis (P < 0.0001). NA is more frequent in men than in women (19.5% versus 14.5%, P = 0.057). Out of the total of 140 NA, 105 (12.9%) were classified as central, 12 (1.5%) as intramucosal and 5 (0.6%) as submucosal forms of NA. 18 times (2.2%) the histologic subtype of NA was not specified. CONCLUSIONS: This study establishes that NA is a frequent, often asymptomatic pathology. In more than half of the macroscopically normal specimens of patients presenting symptoms of acute appendicitis NA can be diagnosed, significantly more than in incidental appendectomies. Therefore it is imperative to remove and analyze a macroscopically normal appendix in a patient presenting symptoms of acute appendicitis if no other intraabdominal pathology can be found.

Acute Disease↗
PubMed2001

Immunogenicity of nonreplicating recombinant vaccinia expressing HLA-A201 targeted or complete MART-1/Melan-A antigen.

The effect on immunogenicity of different tumor T cell epitope formulations was evaluated in vitro using nonreplicating recombinant vaccinia vector expressing two forms of the melanoma-associated MART-1/Melan-A antigen. The first recombinant virus expressed a minigene encoding a fusion product between an endoplasmic reticulum (ER)-targeting signal and the HLA-A201 binding 27-35 peptide. The second viral construct encoded the complete MART-1/Melan-A protein. The capacity of HLA-A201 cells infected with either viral construct to generate and to stimulate MART-1/Melan-A 27-35 specific cytotoxic T-lymphocytes (CTL), was comparatively characterized. The results obtained here with a tumor antigen confirmed the capacity of vaccinia virus-encoded ER-minigene to generate a very strong antigenic signal. In cytotoxicity assays, recognition of target cells infected with high amounts of both recombinant viruses with activated specific CTL clones, resulted in similar lytic activity. With regard to calcium mobilization, TCR down-regulation, IFN-gamma release, and T cell proliferation assays, the targeted epitope elicited 10- to 1000-fold stronger responses. Remarkably, the immunogenic difference between the two formulations, in their respective capacity to generate CTL from naive HLA-A2 peripheral blood mononuclear cells in vitro as measured by tetramer detection, was lower (2- to 3-fold). Recombinant vectors expressing complete antigens have demonstrated their capacity to generate specific responses and such vaccines might take advantage of a broader potential of presentation. However, as demonstrated here for the HLA-A201-restricted MART-1/Melan-A immunodominant epitope, nonreplicative vaccinia virus expressing ER-targeted minigenes appear to represent a significantly more immunogenic epitope vaccine formulation.

Antigen Presentation↗
PubMed2001

[Percutaneous stereotactic biopsy of non-palpable breast lesions using the Advanced Breast Biopsy Instrumentation (ABBI) system: critical evaluation of indication strategies].

PURPOSE: To compare the indications for biopsy with and without the use of the Breast Imaging Reporting and Data System. MATERIAL AND METHODS: Biopsies using the ABBI were performed in 62 patients with 64 non-palpable evident mammographic lesions. The initial decision for biopsy was made by non-radiologists due to suspicious microcalcifications (n = 53) and masses (n = 11). The indication was retrospectively reassessed by adopting the BI-RADS classification by three radiologists in consensus. The positive predictive value (PPV) of both indication strategies was assessed and compared. RESULTS: Biopsies adopting ABBI were performed without major side-effects and were diagnostic. Carcinoma was present in 14 lesions: nine specimens were diagnosed as DCIS and five as invasive carcinomas. For the 50 benign lesions histology revealed mastopathies (26/50) and fibroadenomas (8/50) as the most frequent diagnosis. The positive predictive value (PPV) for the initial indication was 22%, whereas PPV for BI-RADS based indications (categories 4 and 5) was 31%. CONCLUSION: ABBI enables stereotactically-guided procedures that result in representative and diagnostic biopsies. Standardized criteria like BI-RADS improve the PPV and should be a mandatory part of mammographic evaluation. Radiologists should remain involved in the decision making.

Adult↗
PubMed2001

Advanced breast biopsy instrumentation for the evaluation of impalpable lesions: a reliable diagnostic tool with little therapeutic potential.

OBJECTIVE: To assess the potential of advanced breast biopsy instrumentation (ABBI) to clarify the diagnosis of impalpable mammographic lesions and to remove the entire malignant lesions with clear margins. DESIGN: Prospective assessment in a consecutive series of patients. SETTING: University hospital, Basel, Switzerland. SUBJECTS: 139 patients presenting with 144 impalpable microcalcifications or solid nodular densities evident on screening and follow-up mammograms that were suspicious of malignancy. MAIN OUTCOME MEASURES: Feasibility, sensitivity, efficiency in obtaining definitive diagnoses in an outpatient clinic under local anaesthesia, feasibility of complete removal of a primary malignancy, and intervention-related morbidity. RESULTS: The ABBI procedure was successful in 135/144 (94%); an accurate diagnosis was made in 129/130 patients followed up (99%), sensitivity for malignant lesions was 31/32 (97%) and there were 2 complications (2%). Margins of the biopsy cylinder contained a malignant lesion in 26/31 (84%). CONCLUSIONS: Excisional biopsy using the ABBI system is a reliable diagnostic tool with a low morbidity. As in other published series margins were often not clear of tumour and therefore the therapeutic use of the ABBI procedure is limited.

Adult↗
PubMed2000

[The Advanced Breast Biopsy Instrumentation (ABBI) for evaluation of mammographically suspicious, non-palpable findings of the breast: a reliable diagnosis with minor therapeutic potential].

BACKGROUND: Stereotactic biopsy techniques supersede conventional hook-wire localization followed by open excision to clarify the dignity of nonpalpable mammographic lesions. The advanced breast biopsy instrumentation (ABBI) allows stereotactically guided excision of a specimen up to 20 mm in diameter on an outpatient basis under local anaesthesia. METHODS: Demographic information, mammographic and pathological findings, complications, subsequent interventions and sensitivity as well as efficiency of a series of 144 planned ABBI procedures were documented (largest published single institution series). RESULTS: The ABBI procedure was successfully performed in 93.8% (135/144); accurate diagnosis was made in 99.3% (134/135), sensitivity for malignant lesions was 96.9% (31/32) and morbidity was 1.5%. Consistent with other published series margins of the biopsy cylinder containing a malignant lesion were involved in 83.9% (26/31). CONCLUSIONS: Excisional biopsy using the ABBI system is a reliable diagnostic tool with a low incidence of morbidity. The therapeutic use is of limited potential.

Adult↗