Search PubMed⌕ Search

Biomedical subjects

E Scherer

Publications and source records attributed to E Scherer.

At least 73 records · Page 4Linked to original sources
PubMed1984

[Current state and possibilities of radiotherapy in the inter- disciplinary treatment of malignancies of the stomach, pancreas and biliary tract. II. Pancreatic cancer].

The extremely unfavorable prognosis of the carcinoma of the pancreas is due to the fact that a curative operation - even by ultraradical surgery - is already impossible in 75 to 90% of patients at the moment of diagnosis. Contrary to expectation this situation has not been essentially improved by the introduction of modern, non-invasive examination methods such as ultrasound and computed tomography. Thus medical science is confronted again with the task of searching for operation modalities, especially for patients whose tumors are curatively inoperable but still restricted to the pancreatic region. Today the efficacy of radiotherapy can be considered to be proved also with respect to the carcinoma of the pancreas. The available results seem to indicate that the effect of radiotherapy depends on the dose and that the combination of radiotherapy and chemotherapy is more efficient than radiotherapy alone. It is not known yet if the effect of additional chemotherapy is only of a locally adjuvant or also of a systemic nature. Similarly to the carcinoma of the stomach, direct intraoperative irradiation - alone or combined to percutaneous irradiation - brings about the greatest effect. The authors present the surgical, radiotherapeutic, and chemotherapeutic results achieved hitherto in the treatment of the locally advanced carcinoma of the pancreas. Further possibilities for the future use of radiotherapy are proposed in order to encourage the establishment and application of interdisciplinary therapy conceptions.

Adenocarcinoma↗
PubMed1983

Neutron and neutron-boost irradiation of soft tissue sarcomas: a 4.5 year analysis of 139 patients.

A 4.5 year analysis of neutron and neutron-boost therapy is presented for 139 patients with soft tissue sarcomas. The actuarial survival rate of all patients is 64.3%, the disease-free survival rate is 61.6%. Significant differences in local control rates were found as a function of tumour stage (100% for T1, 72% for T2 and 46% for T3; p: 0.018) and as a function of the presence (50.5%) or absence of clinical evidence of tumour at the time of irradiation (76%; p: 0.002). The corresponding actuarial survival rates are 90.1% for T1 tumours, 78.5% for T2 tumours and 51.2% for T3 tumours, and on the other hand, 50.5% for patients with gross tumour and 76% for patients with no clinical evidence of tumour. A rather high morbidity rate (31/111, i.e. 28%) was observed after full neutron treatment. In order to reduce this complication rate, a combination of photons and a neutron boost was adopted. On 28 patients treated up to now, only two severe complications were observed. The effectiveness of this treatment regimen is presently being evaluated in a prospective European Organization for Research on Treatment of Cancer (EORTC) trial.

Adolescent↗
PubMed1983

Present interdisciplinary treatment regimen for advanced head and neck tumours at the West German Tumour Centre, Essen.

Apart from the classic combination of surgery and irradiation, four other treatment modalities are presently being evaluated in advanced head and neck tumours. These are: 1) antineoplastic chemotherapy 2) radiosensitizing agents 3) high LET radiotherapy 4)local hyperthermia Preoperative chemotherapy, followed by surgery and irradiation, has improved the local control as well as survival rates in phase II trials. Cis-platinum may yield some additional benefit due to its radiosensitizing properties. Radiosensitizing drugs such as nitro-imidazoles have so far failed to show any advantage in randomized trials, since neurotoxicity prevented maximum effective concentrations. The same is true for high LET radiotherapy with neutrons as compared to conventional irradiation. Local hyperthermia is considered as a palliation at the present time, when all other treatment modalities have been exhausted. In our centre, the preliminary results of radiotherapy and sensitization with cis-platinum in combination with surgery are encouraging. Some methods are discussed which permit the prediction of prognostic criteria for tumors under treatment. This may contribute to the optimization of individual treatment regimes in the future.

Antineoplastic Agents↗
PubMed1983

[Local hyperthermia in the treatment of advanced tumors: curative and palliative effects].

During the years of 1978 to 1981, a pilot study was conducted with 210 patients suffering from 235 tumors. The treatment included localized high-frequency hyperthermia alone or combined with radiotherapy and/or chemotherapy. The final evaluation of 164 tumors with different sites, sizes and histologic findings shows that even if the patients collective is unfavorably selected (nearly all tumors in an advanced stage), an increased palliative effect exceeding the clinical effect expected for radiotherapy alone was reached in 60 to 70% of all cases. 45% of the patients showed curative effects in the sense of an objectively improved tumor remission. At the same time, a significant reduction of local side effects of radiotherapy was achieved by the hyperthermic treatment. Localized hyperthermia until 42/43 degrees C has only a small rate of complications, even if it is applied in the abdominal region. Within the relatively short follow-up period, an increased rate of metastases after therapy combinations with hyperthermia was not observed.

Combined Modality Therapy↗
PubMed1983

[Significance of radiotherapy in the treatment of soft tissue sarcomas].

Postoperative photon- or electron irradiation has been well established in the treatment of soft tissue sarcomas. For further improvement of these results, neutron- or neutron-boost irradiation was introduced at several centres of radiation therapy. In this report, the 3.5 year results of 112 patients are analysed. The majority (62%) had T3-tumours (UICC classification, Geneva 1978). 58 patients presented with gross tumour at the beginning of radiotherapy, and 54 patients without clinical evidence of tumour. 39 patients (35%) had recurrent tumours. A highly statistical difference in local tumour control was found between the group of patients with gross tumour (47%) and the group of patients without clinical evidence of tumour (81%). A statistical difference in local control and survival was also found between the group of patients with T1-tumours (100%), T2 tumours (76.8%) and T3 tumours (44.5%), whereas no differences were found in terms of grading. The high complication rate of 25%, which was found after neutron therapy, was reduced to 7% after introduction of a neutron boost. The statistical significance of this treatment modality is presently being evaluated in a randomised EORTC trial. Adjuvant chemotherapy is recommended für all G3 tumours.

Adolescent↗
PubMed1983

[A new interdisciplinary treatment concept for head and neck tumors. Fundamentals, practicability and initial clinical results].

Surgery and subsequent irradiation are still considered as the basic treatment of advanced head and neck tumours. Improvements may be achieved by initial combined chemotherapy. However, this regimen has not yet been statistically substantiated. In order to reduce the therapeutic morbidity, Cis-platinum was given as a cytotoxic and radiosensitizing agent simultaneously with percutaneous irradiation. In case of partial tumour regression after a target volume dose of 40 Gy, radiotherapy was continued up to 60 or 70 Gy respectively. In case of minor tumour response, surgery was interposed after a dose of 40 Gy, followed by completing radiotherapy. After a maximum follow-up period of 14 months, 18 out of 22 patients show no evidence of tumour. In two cases a partial regression is seen. One patient died from intercurrent disease, another from uncontrolled primary. This tumour control rate is comparable to the data achieved with initial combined chemotherapy regimens, at a lower level of morbidity. Our preliminary results seem to corroborate the experimentally proven enhancement effect of Cis-platinum.

Cisplatin↗
PubMed1983

[Radiotherapy of the hemangioma of the choroid].

For the first time, a report is given on the percutaneous radiotherapy of hemangiomas of the choroid which could not be treated by photocoagulation. Diagnosis and control examinations of these tumors were performed by ophthalmoscopy, fluorescence angiography, and ultrasonography. Ten eyes (nine patients, three out of them with Sturge-Weber's disease) were treated between 1967 and 1982. A first group (five eyes, five patients) treated until 1974 received a target volume dose of 1,65 to 6,5 Gy combined with subsequent photocoagulation. All these eyes could be preserved. In addition, the second group (five eyes, four patients) treated since 1975 with unique radiotherapy showed better results with respect to visual acuity. The average follow-up period was four years (seven months up to nine years). Late effects were not observed. Even in case of advanced disease with retinal ablation and secondary glaucoma, an inactivation of the hemangioma of the choroid and a simultaneous regression of the secondary alterations could be achieved. According to our experiences, enucleations can be prevented by an irradiation with a target volume dose of 20 to 30 Gy.

Adolescent↗
PubMed1982

[Bone marrow transplantation for aplastic anaemia and acute leukaemia (author's transl)].

Twenty-six bone marrow transplantations were performed at the West Germany Tumour Centre at Essen between December 1975 and December 1981. Three patients had aplastic anaemia, 23 acute leukaemia. Of the leukaemia patients 13 had a recurrence and ten were in full remission at the time of the transplantation. Two of the patients with a recurrence received deep-frozen autologous marrow from the remission phase. One patient with aplastic anaemia had an identical twin as donour, while all other patients received allogeneic marrow from histocompatible family members. Eleven patients are still alive, all three of those with aplastic anaemia, one of those with leukaemia in a recurrence, and seven of those with acute leukaemia in full remission. Two of the survivors have a chronic graft-host reaction, but the others are symptom-free, after an observation period of up to four years. Main causes of death were leukemic recurrence (6), infection (5), and graft-host reaction (2). It would seem that at present bone marrow transplantation offers the best chance of a cure for severe aplastic anaemic and acute leukaemia in adults, but only if transplantation is undertaken early and not in the end-stage of the disease.

Acute Disease↗
PubMed1982

Measurement of O6-ethyldeoxyguanosine and N-(deoxyguanosin-8-yl)-N-acetyl-2-aminofluorene in DNA by high-sensitive enzyme immunoassays.

Antibodies raised in rabbits against the bovine serum albumin conjugates of O6-ethylguanosine and N-(guanosin-8-yl)-N-acetyl-2-aminofluorene have been used to develop a high-sensitive enzyme-linked immunosorbent assay (HS-ELISA) for the quantification of adducts in DNA modified by ethylating agents and N-acetyl-2-aminofluorene. Linear dose-response relations were obtained in the non-competitive HS-ELISA between 0.5 fmol and 50 fmol O6-ethyldeoxy-guanosine per 2.8 microgram DNA, and between 0.1 fmol and 20 fmol N-(deoxyguanosin-8-yl)-N-acetyl-2-aminofluorene per 0.8 microgram DNA. The sensitivity of an ultrasensitive radioimmunoassay was in the same order of magnitude. Modification levels as low as 0.1 mumol of adduct/mol DNA-nucleotides (1: 10(7)) can be detected by each assay.

2-Acetylaminofluorene↗
PubMed1982

[Combined surgical and radiologic treatment of anal cancer].

The different ways of metastases of carcinoma of the anus can hardly be removed by radical surgery and require other procedures than the lower carcinoma of the rectum. In comparing Miles operation in T3/T4 carcinomas of the anus with the combined therapy of local excision and radiotherapy results showed no great difference in T1/T2 tumors the Miles operation is not necessary. In T3/T4 carcinomas irradiation derives its worth from the few possible procedures ro radical surgery. In T1/T2 tumors irradiation can be an alternative (T1) or an additional treatment (T2) to the local excision.

Adenocarcinoma↗
PubMed1982

[Clinical significance of time dose distribution in radiotherapy].

A survey is given of the mathematical and empirical methods allowing to compare different chronological dose distributions; their possibilities and limits are described. The experimental bases of hyper- and superfractionation and the clinical experiences gained hitherto with multiple daily irradiations are communicated; radiotherapy with high individual fractions and long term irradiation are shortly explained. Finally some hints are given for the further development and the practical use of not typical fractionation schemes.

Humans↗
PubMed1981

Persistence and accumulation of (potential) single-strand breaks in liver DNA of rats treated with ethyl methanesulphonate.

In vivo alkylation of DNA leads to DNA fragmentation in alkaline sucrose gradients. In a previous paper (Chem.-Biol. Interact., 19 (1977) 111) we presented evidence that, depending on the experimental conditions, a major fraction of the single-stranded breaks observed might be derived from alkali-labile alkylphosphotriesters. Using alkaline gradients the present paper shows that injection of ethyl methanesulphonate (EMS) into Sprague-Dawley female rats results in significantly increased liver DNA fragmentation up to at least 56 days after injection. Accumulation of single-strand breaks was indicated by experiments in which at 6 days after the last of a series of 5 weekly EMS injections (5 X 110 mg/kg) 11.4 breaks/10(9) Dalton were found, being 3 times more than the number of breaks observed at 6 days after a single injection of 110 mg/kg EMS (3.8 breaks/10(9) Dalton). In animals treated with methyl methanesulphonate (MMS) single-strand breaks were observed at 4 h, 1 day and 2 days, but not at 6 days after injection (40 mg/kg). Repeated weekly injections of MMS (5 X 40 mg/kg) did not result in increased numbers of breaks when compared with animals receiving a single injection of this agent (1 X 40 mg/kg; animals were killed 1 day after (the last) injection). It is suggested that MMS-induced breaks are derived, either on the gradient or in situ, from apurinic sites, whereas persistent EMS-induced breaks reflect the presence of ethylphosphotriesters. The results are discussed in relation to the lacking capacity of EMS to induce foci of precancerous lesions in rat liver and the non-hepatocarcinogenic properties of both MMS and EMS.

Alkylation↗
PubMed1981

Sleeve lobectomy: an alternative to pneumonectomy in the treatment of bronchial carcinoma.

In a 20-year period between 1960 and 1979, 3,438 resections were done for primary cancer of the lung, the standard operation being either lobectomy or pneumonectomy in more than 90% of the cases. In 261 cases (7.4%) sleeve lobectomy was performed as an alternative to pneumonectomy in order to conserve pulmonary function as far as possible, provided the operation assured as equally radical a removal of the tumor as pneumonectomy. Long-term results could be evaluated for 113 cases operated before 1974. Fifty-seven (50%) were alive at least 5 years after operation, the follow-up being 100%. The postoperative mortality was 7.3% (19 cases). Indications for sleeve resection as well as some aspects of anesthesia and surgical technique are discussed.

Adenocarcinoma↗