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M Treiber

Publications and source records attributed to M Treiber.

At least 19 recordsLinked to original sources

[Intraoperative radiotherapy as part of the treatment concept of soft tissue sarcomas].

The therapy of soft tissue sarcomas is not uniform. The goal of treatment for soft tissue sarcomas is surgical resection with negative microscopic margins. Other therapy options are pre-, intra-, or postoperative radiotherapy as well as neoadjuvantor adjuvant chemotherapy with different drugs, systemic or under local perfusion of the limb. If a margin-free surgical resection is not possible, intraoperative radiation therapy (IORT) offers the possibility for treatment of sites at high risk for local recurrence. The goal of this collaborating study of the Orthopedic University Hospital of Heidelberg and the department of Radio-Oncology of the University Hospital of Heidelberg is to observe the influence of IORT on the rate of local recurrence, complications, metastases, and survival in another wise unchanged tumor management. From 1960 to 1998,78 patients were treated for soft tissue sarcomas; 26 of 78 patients underwent intraoperative radiation and 52 patients were treated without intraoperative radiation. We found a recurrence rate of 15% in the IORT group and 29% in the non-IORT group. No difference for survival or distant recurrence was found, also no difference in early postoperative complication rate, but a higher rate of late complications after IORT (34% vs 7%) was remarkable. We think intraoperative radiation allows better local control and for that reason IORT is integrated into our therapeutic concept. Its influence on survival and distant metastases needs further investigations.

Adolescent↗

[Intraoperative extracorporeal irradiation and replantation in local treatment of primary malignant bone tumors].

In 13 patients with primary malignant bone tumors (10 Ewing's sarcoma, 1 parosteal osteosarcoma, 1 adamantinoma recurrence, and 1 MFH) local therapy was performed as intraoperative extracorporeal irradiation and replantation (IEIR) of the involved bone segment (5 tibia, 2 femur, and 6 pelvis). Of the 13 patients (69%), 9 are alive at the time of the follow-up (5 CDF, 4 AWM(treated)) and 4 patients died of disease (DOD). Up to now during the follow-up of 32 months (6-57), no local recurrence was observed in the replanted bone segments. The complication rate was very high (18 complications in 11 of the 13 patients, including 6 cases with complication V degrees according to Ruggieri with loss of the reconstruction). The typical complication is severe local infection necessitating removal of the replant. In cases of mechanical failure, the replanted segment could mostly be preserved by surgical revision and autologous bone grafting. If serious complications can be managed or avoided, functional results can be achieved. IEIR must be seen as an extraordinary reconstruction procedure in cases where established procedures such as endoprosthesis, biological reconstructions, or rotationplasties cannot be used or are refused by the patient.

Adolescent↗

[Improving local control in patients with aggressive fibromatosis by combined surgery and radiotherapy].

INTRODUCTION: The purpose of this retrospective analysis is to evaluate whether the combination of surgery and radiation therapy in patients with aggressive fibromatosis influences the therapeutic outcome. METHOD: Clinical, radiological and pathological results of 23 consecutive cases with histologically proven aggressive fibromatosis were retrospectively analyzed. The median follow-up was 59 months. RESULTS: Twelve patients received surgery alone for their first treatment, 10 patients had a combination of surgery and radiotherapy and 1 patient had radiochemotherapy. Of 23 patients 14 (63%) had one or more local recurrences and 9 (39%) were recurrence-free. The patients received a total of 50 treatments: 29/50 (58%) treatments were followed by a local recurrence and 21/50 (42%) were without relapse. Twenty-nine treatments with local recurrence consisted of 25/29 (86%) surgical treatments, 3/29 (10%) combinations of surgery and radiation therapy, and 1/29 (3%) radiochemotherapy. Of the patients who had only surgery for their first treatment, after one year 8 of 12 (66%) and after 5 years all patients had a local recurrence. In the group with surgery and radiotherapy, there was no recurrence after 1 year and 1 recurrence after 5 years (p = 0.0001). CONCLUSION: We recommend a complete tumor resection, without mutilating the patient. Radiation therapy in combination with surgery in contrast to surgery alone is an efficient treatment option for reducing local recurrence.

Adolescent↗

Daily patient set-up control in radiation therapy by coded light projection.

Advances in conformal radiation therapy to control disease via dose escalation are challenged by set-up uncertainties. Recently, techniques have been developed to use surface features to evaluate the patient's position and correct it where necessary. The aim of this study was to use the patient's surface as a tool for daily set-up control and monitoring. We use a surface scanner based on the projection of coded light to receive--in a daily routine--a large amount of surface points which enables us to register the CT-based planning data with the patients current position. By superimposing current and planned volumes, a volume of congruency was obtained. An error below 1 mm was considered acceptable. In cases where set-up was not satisfactory a map of the surface comparison was evaluated showing the areas of missing alignment. According to this information a manual repositioning was performed. This procedure was repeated until the error was acceptable. No more then 3 repetitions where necessary to obtain an acceptable result. The whole procedure including registration, calculation and visualization took about 20 sec for one repetition. The use of structured light projection in the daily set-up control and monitoring proved to be a noninvasive, easy, quick, inexpensive and reliable solution.

Data Collection↗

Non-infectious lung complications are closely associated with chronic graft-versus-host disease: a single center study of incidence, risk factors and outcome.

Non-infectious lung complications (NILC) are frequent, influencing morbidity and mortality of patients after allogeneic BMT. Although the term NILC encompasses a number of different entities, an association with GVHD has been noted for almost all of them. Our study was directed towards assessing the incidence and risk factors for developing NILC, as well as the response to treatment and long-term outcome. Forty (14.7%) out of 272 patients surviving for more than 3 months after allogeneic BMT, developed lung complications fulfilling the criteria for NILC. The evaluation was based on clinical investigation, radiologic imaging, lung function tests, broncho-alveolar lavage and biopsies. Risk factors were assessed by univariate and multiple statistical regression models, where chronic GVHD proved to be the only significant risk factor for the development of NILC (P = 0.011). In three patients NILC developed in direct association with donor lymphocyte infusions. The majority of patients responded well to treatment with corticosteroids and immunosuppressive drugs. NILC had no adverse effect on survival. The frequency of NILC was low in autologous (5%) as compared with allogeneic transplants (14.7%) but this difference was not statistically significant. Bone Marrow Transplantation (2000) 25, 1263-1268.

Bone Marrow Transplantation↗

Congested traffic states in empirical observations and microscopic simulations

We present data from several German freeways showing different kinds of congested traffic forming near road inhomogeneities, specifically lane closings, intersections, or uphill gradients. The states are localized or extended, homogeneous or oscillating. Combined states are observed as well, like the coexistence of moving localized clusters and clusters pinned at road inhomogeneities, or regions of oscillating congested traffic upstream of nearly homogeneous congested traffic. The experimental findings are consistent with a recently proposed theoretical phase diagram for traffic near on-ramps [D. Helbing, A. Hennecke, and M. Treiber, Phys. Rev. Lett. 82, 4360 (1999)]. We simulate these situations with a continuous microscopic single-lane model, the "intelligent driver model," using empirical boundary conditions. All observations, including the coexistence of states, are qualitatively reproduced by describing inhomogeneities with local variations of one model parameter. We show that the results of the microscopic model can be understood by formulating the theoretical phase diagram for bottlenecks in a more general way. In particular, a local drop of the road capacity induced by parameter variations has essentially the same effect as an on-ramp.

Journal Article↗

Intraoperative radiotherapy for primary and locally recurrent soft tissue sarcoma: morbidity and long-term prognosis.

INTRODUCTION: Soft tissue sarcoma has a high risk of local recurrence. Therefore, extensive surgical resection has been combined with radiotherapy to improve long-term results. Because external beam radiation doses may be limited by adjacent radiosensitive tissue, intraoperative boost radiation has been devised to achieve a higher total radiation dose in combination with external beam radiotherapy. We report our experience with this multimodal approach for primary and recurrent soft tissue sarcoma. METHODS: Clinical and pathological data were extracted from a prospective data base including all patients with a diagnosis of soft tissue sarcoma treated at the Department of Surgery, University of Heidelberg between 1988 and 1999. Intraoperative radiotherapy dosages were 12-15 Gy for the extremities and 15-18 Gy for the trunk and the retroperitoneum. Additional external beam radiotherapy was given at 40 Gy, whenever possible. RESULTS: Between 1988 and 1999, a total of 251 patients with primary or recurrent soft tissue sarcoma of the extremities, the trunk or the retroperitoneum were treated. The mean (+/- SD) age of 136 men and 115 women was 53+/-16 years. Five of 251 patients died post-operatively, giving a mortality rate of 2.0%. Intraoperative radiotherapy (IORT) was used in 92 patients (37%). Surgical complications were more frequent in IORT patients (30 of 92; 33%) compared to non-IORT patients (36 of 159; 23% P=0.1). Infectious complications were significantly more frequent in patients receiving IORT (P=0.03). Two hundred and four patients were macroscopically tumour-free (R0, R1 resection). For these patients multivariate analysis identified grading (relative risk (RR) 3.1-6.6; P<0.001), age (over 55 years; (RR) 1.8: P<0.008) and tumour location in the retroperitoneum (RR 2.2; P<0.004) as independently associated with recurrence-free survival. The use of IORT (P<0.02) reduced the relative risk of death or recurrence by 40% (RR 0.6; P<0.02). Sex, primary vs. recurrent tumour, T classification and R-status (R0 vs. R1) were not significantly related to recurrence-free survival. CONCLUSIONS: In this prospective, non-randomized study of soft tissue sarcoma IORT was associated with a higher rate of infectious complications, but the the risk of death or recurrence was reduced by 40%.

Adolescent↗

Moderate dose intraoperative and external beam radiotherapy for locally recurrent rectal carcinoma.

BACKGROUND AND PURPOSE: Late adverse effects (i.e. neuropathy, chronic bowel obstruction) limit the effective dose given in intraoperative radiotherapy (IORT) and external beam radiotherapy (EBRT). Initial results of a multi-modality treatment approach using moderate dose IORT and moderate dose EBRT are presented. PATIENTS AND METHODS: Thirty-one consecutive patients with recurrent rectal carcinomas had IORT and EBRT after complete (R0, n = 14) or incomplete resection (R1, n = 9; R2, n = 8). The mean [ORT dose was 13.7 Gy (range 12-20 Gy) supplemented with an EBRT dose of 41.4 Gy. Twenty-two patients had preoperative EBRT and 22 patients had concomitant chemotherapy (5-FU, Leucovorine). RESULTS: After a median follow-up of 28 months, 16 patients had re-recurrent disease and 11 patients had died. Nine patients failed locally (four in-field, four marginal and one anastomotic re-recurrence), three combined with distant metastasis, resulting in overall and IORT infield local control rates of 71% and 87%, respectively. Distant metastases alone were found in seven patients. The 4-year overall and relapse-free survival rates were 58% and 48%, respectively. After incomplete resection the local failure rate increased (R0 21%, R1/2 35%) and the 4-year relapse-free survival rate decreased significantly (29% versus 71%) due to a markedly increased distant metastasis rate (53% versus 7%). Acute and late toxicities were not increased. CONCLUSION: The combination of moderate dose IORT and EBRT is a safe and efficacious component in a multi-modality treatment approach.

Antineoplastic Agents↗

Pediatric ambulance utilization in a large American city: a systems analysis approach.

BACKGROUND: Research on utilization of ambulances by pediatric patients lacks an objective, reproducible tool for the evaluation of patterns of ambulance use by both the providers and the users of this resource. OBJECTIVES: 1) To develop an objective, diagnosis-based measure of appropriateness of ambulance utilization. 2) To use the measure to evaluate whether Municipal Ambulance Service dispatchers assign ambulances appropriately, and whether parents/caretakers request ambulances appropriately. STUDY DESIGN: 1) Development of the pediatric ambulance need evaluation (PANE) tool: The consensus of an expert panel was used to assign patients arriving by ambulance to three levels of prehospital transport need based upon their ultimate hospital discharge diagnoses, and were as follows: required advanced life support ambulance (ALS); required basic life support ambulance (BLS); required a less acute mode of transport (LAT). 2) Assessment of appropriateness of ambulance assignments by EMS call-receiving operators (CRO) and of ambulance requests by parents/caretakers: Comparison of actual type of ambulance assigned and of need for ambulance, using the PANE tool and hospital admission rates as gold standards. DATA COLLECTION: Level of prehospital transport provided (ALS vs BLS), ultimate ED diagnosis, and ED disposition (admission vs discharge) was collected for each patient from information abstracted from the prehospital and ED records. SETTING: Bellevue Hospital Center and Harlem Hospital Center, two level I trauma centers in New York City, both with Pediatric Emergency Departments staffed 24 hours a day by attending physicians and residents. PATIENT SELECTION: Consecutive sample of 2633 patients, birth to 18 years of age, who arrived to either hospital by ambulance as primary transports from the field over a one-year period. RESULTS: 1) Development of PANE tool: At Bellevue Hospital, 7% of ED visits arrived by ambulance; at Harlem Hospital, 5% arrived by ambulance. Using these ambulance arrivals, 215 diagnoses were identified for inclusion in the PANE tool. An expert panel categorized each diagnosis as requiring ALS, BLS, or LAT, with a high level of interobserver agreement (weighted kappa = 0.793). As a measure of external validity of the PANE, admission rates were highest in the ALS group, next highest in the BLS group, and lowest in the LAT group (chi2 for trend, P < 0.05). 2) Assessment of ambulance assignments and requests: According to the PANE tool, the sensitivity of dispatcher assignment of ALS ambulances was 72 %. Therefore, 28 % of patients who required an ALS ambulance received BLS care. 50% of patients assigned to an ALS ambulance did not require that level of care, and 1/3 of these were categorized by the PANE as not requiring an ambulance at all. CONCLUSIONS: The PANE tool compared favorably to admission rates as a measure of the severity of illness of patients arriving by ambulance. Applying the PANE tool, we conclude that the majority of requests for ambulances are appropriate, and that the majority of the time dispatchers were able to dispatch the appropriate level of care. However, there is room for significant improvement in utilization of ambulances, and tools like the PANE will be useful in achieving this goal.

Adolescent↗

Certified first responder: a comprehensive model for pediatric training.

The purpose of this document is to present a general approach to educating the First Responder in Emergency Pediatric Care. The First Responder is especially important in the emergency care of the sick or injured child. The majority of mortality and morbidity associated with pediatric emergencies is a result of airway and ventilatory compromise. In addition, most airway and ventilation problems can be corrected with only basic life support interventions that are within the scope of practice of the First Responder. As a result, it is of paramount importance to assure that the First Responder is adequately trained in the initial care of the pediatric patient. This document will review some of the key objectives and topics which the First Responder needs to understand in order to adequately care for children until further emergency care arrives. Templates for lesson plans and suggested activities for training the First Responder are also presented.

Certification↗