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J Dunst

Publications and source records attributed to J Dunst.

At least 73 records · Page 4Linked to original sources
PubMed1998

Oxygenation of squamous cell carcinoma of the head and neck: comparison of primary tumors, neck node metastases, and normal tissue.

BACKGROUND: Most previous oxygenation measurements of head and neck tumors have mainly been performed in neck nodes. We investigated, therefore, the relationship between the pO2 status of primary tumors, cervical neck node metastases and normal tissues. PATIENTS AND METHODS: 30 patients with histologically proven advanced stage III-IV squamous cell carcinoma of head and neck underwent pretreatment polarographic pO2 measurements with a pO2 histograph (Eppendorf, Hamburg, Germany). We obtained data on oxygenation of 23 primary tumors, of 22 neck node metastases, and of 30 contralateral sternocleidomastoid muscles. In 15 cases, we were able to perform measurements in all three regions in the same individual. results: A highly significant correlation existed between the median pO2 of primary tumors and their neck node metastases (p=0.0001), as well as between the proportion of pO2 values < or =2.5 mmHg and +/-5.0 mmHg (p=0.0001, p=0.001) in both anatomic sites. The average pretreatment median PO2 was 14.7 mmHg (range 0.2-58.5 mmHg) in primary tumors, 13.7 mmHg (range 1.9-50.3 mmHg) in neck node metastases, and 43.8 mmHg (range 20.8-67.7 mmHg) in sternocleidomastoid muscles. In all cases, the oxygenation of malignant tissue was below that of the corresponding muscle. There was also a weak, but significant, correlation between hemoglobin level and the median pO2 of the primary tumors, as well as between hemoglobin concentration and the proportion of values below 5 mmHg at the primary site (p=0.017, p=0.003). CONCLUSIONS: Primary tumors and their regional lymph node metastases in advanced squamous cell carcinoma of the head and neck show comparable patterns of oxygenation in terms of the median pO2 and the proportion of hypoxic measurements. This report suggests that, in patients with such carcinomas, the oxygenation data obtained at one site are related to tumor oxygenation at other sites, so that measurements in any anatomic site would be sufficient to estimate a tumor's oxygenation status. The weak correlation between pO2 and hemoglobin level requires further investigation.

Adult↗
PubMed1998

A 2-week pretreatment with 13-cis-retinoic acid + interferon-alpha-2a prior to definitive radiation improves tumor tissue oxygenation in cervical cancers.

BACKGROUND: We have evaluated the tumor tissue pO2 in cervical cancers in patients treated with 13-cis-retinoic acid and interferon-alpha-2a prior to and during radiotherapy. PATIENTS AND METHODS: From June 1995 through April 1997, 22 patients with squamous cell carcinoma FIGO IIB/III of the cervix who were scheduled for definitive radiotherapy with curative intent received additional treatment with 13-cis-retinoic acid (cRA, isotretinoin) plus interferon-alpha-2a (IFN-alpha-2a) as part of a phase-II protocol. cRA/IFN-alpha-2a started 14 days prior to radiotherapy (1 mg per kilogramme body weight cRA orally daily plus 6 x 10(6) IU IFN-alpha-2a subcutaneously daily). After this induction period, standard radiotherapy was administered (external irradiation with 50.4 Gy in 28 fractions of 1.8 Gy plus HDR-brachytherapy). During radiotherapy, cRA/IFN-alpha-2a treatment was continued with 50% of the daily doses. Tumor tissue pO2-measurements were performed prior to and after the cRA/IFN-induction period as well as at 20 Gy and at the end of radiotherapy with an Eppendorf-pO2-histograph. RESULTS: In 11 out of the 22 patients, pO2-measurements were performed prior to the cRA/IFN-induction therapy. The median pO2 of these untreated tumors was 17.7 +/- 16.3 mm Hg. The relative frequency of hypoxic readings with pO2-values below 5 mm Hg ranged from 0% to 60.6% (mean 24.3 +/- 21.0%). After the 2-week induction period with cRA/IFN, the median pO2 had increased from 17.7 +/- 16.3 mm Hg to 27.6 +/- 19.1 mm Hg (not significant). In all 5 patients with hypoxic tumors prior to cRA/IFN (median pO2 of 10 mm Hg or less), the median pO2 was above 20 mm Hg after the 2-week cRA/IFN-induction. In this subgroup of hypoxic tumors, the median pO2 increased from 6.3 +/- 2.7 mm Hg to 27.0 +/- 5.6 mm Hg (p = 0.004, t-test for paired samples). The frequency of hypoxic readings (pO2-values < 5 mm Hg) decreased from 44.7 +/- 17.1% to 2.0 +/- 2.5% (p = 0.012, t-test for paired samples). There was, however, no obvious volume reduction after 14 weeks of cRA/IFN on clinical examination. A complete clinical remission of the local tumor was observed in 19/22 patients after radiotherapy and additional cRA/IFN-alpha-2a-treatment. In primarily hypoxic tumors (with a median pO2 below 10 mm Hg prior to treatment), 4/5 achieved complete remission. CONCLUSIONS: Pretreatment with cRA/IFN improves oxygenation of primarily hypoxic cervical cancers. The mechanisms of action remain unclear and further investigation of the combination regimen is recommended.

Aged↗
PubMed1998

p53 status in radiation-induced soft-tissue sarcomas.

BACKGROUND: Following therapeutic irradiation after a latency period of many years radiation-induced tumors, often sarcomas, can arise. Results of radiation-induced DNA damage can be 1. p53 over-expression, inducing growth arrest or apoptosis, and 2. occurrence of mutations, frequently including the p53 gene, as one molecular promotor for carcinogenesis. We were interested whether radiation-induced sarcomas are associated with alterations of the p53 status. MATERIAL AND METHODS: Samples from 11 radiation-induced soft-tissue sarcomas (STS) were studied by a non-radioactive PCR-SSCP sequencing analysis and by immunohistochemistry with five antibodies for their p53 status. RESULTS: A tumor of one patient possessed a G->A transition in codon 280 (exon 8). Of 11 tumors, 9 showed nuclear p53 positivity, detected by monoclonal antibody DO-1. Of these 9 patients, 7 died during the observation period, whereas the 2 patients with DO-1 negative tumor samples are still alive. CONCLUSIONS: p53 over-expression and p53 mutation occur in radiation-induced STS. p53 status is expected to have prognostic impact for radiation-induced STS.

Adult↗
PubMed1998

[Oxygenation status of squamous cell carcinoma of the head and neck: comparison of primary tumors, their neck node metastases and normal tissue].

AIM: Investigation of the relationship between the pO2-status of primary tumors, their cervical neck node metastases and normal tissues in squamous cell carcinomas of the head and neck. PATIENTS AND METHODS: Pretreatment oxygenation of primary tumors, their neck node metastases and of the contralateral sternocleidomastoid muscle was assessed in 16 patients with histologically proven advanced squamous cell carcinomas of head and neck. Oxygenation was measured with a polarographic microelectrode system (Eppendorf-pO-Histograph). Using CT/MRT additionally the volume of the tumors was estimated. RESULTS: A highly significant correlation existed between the median pO2 of primary tumors and their neck node metastases and between the relative proportion of hypoxic values (< 5 mm Hg) of both anatomic sites (both p = 0.0001) (Figure 1). Primary tumors were not different from their neck node metastases, neither regarding the pO2 median values nor in view of the relative frequency of hypoxic values (Table 1). No correlation was found between the volume of primary tumors and the one of their neck node metastases. For volume of tumors and the oxygenation status no relationship was found as well. Significantly different was the median pO2 in the muscles from the one of the malignant tissues (p = 0.0004). CONCLUSION: The results suggest that for to estimate the oxygenation status of squanious cell carcinomas of the head and neck pO2 measurements of primary tumors and neck node metastases are equally sufficient.

Carcinoma, Squamous Cell↗
PubMed1998

Acute radiation reaction and local control in breast cancer patients treated with postmastectomy radiotherapy.

BACKGROUND: We have investigated the variation of acute radiation reactions in medium-risk patients with postmastectomy radiotherapy with regard to a possible correlation between radiation reaction of normal tissues and local tumor control. MATERIAL AND METHODS: From 1985 through 1991, a total number of 194 patients received postmastectomy radiotherapy for breast cancer pT1-2pN0-2M0 at the University of Halle-Wittenberg. The lymphatics were irradiated by an anterior 9-MV photon field and the chest wall by an individually shaped anterior field with 9-MV electrons. Both fields received single doses of 2 Gy 5 times weekly up to a total dose of 44 Gy to the chest wall and 50 Gy to the lymphatics. All patients were routinely evaluated once weekly during radiotherapy for acute side effects by one examiner. Skin erythema was classified as mild, moderate or severe, esophagitis as being present in form of dysphagia or not and pneumonitis, if present, as asymptomatic (visible only on repeated chest X-rays) or clinically symptomatic. A differential blood count was also carried out once weekly. For this analysis, the records of all patients were retrospectively reviewed. The median follow-up at the time of analysis was 4.2 years. RESULTS: Of the patients, 98 (51%) had a mild, 53 (27%) moderate and 43 (22%) a severe erythema. Furthermore, 38 patients (20%) had signs of esophagitis, 13 (7%) had asymptomatic and 26 (13%) symptomatic pneumonitis. Patients with severe erythema or erythema plus esophagitis and pneumonitis had a more pronounced decrease in lymphocyte count during treatment than patients with mild erythema: the lymphocyte nadir was 0.14 vs 0.73 Gpt/l in patients with severe vs mild erythema, and 0.36 vs 0.69 Gpt/l in patients with erythema plus esophagitis plus pneumonitis vs patients with erythema only, p < 0.05. Of the patients, 44 (22%) developed chronic side effects, mostly arm edema. There was no correlation between acute and late effects. An overall number of seven local recurrences (3.6%) occurred. The risk of developing a local recurrence within 5 years after treatment was 0% in patients with severe erythema or erythema plus esophagitis/pneumonitis vs 7% in patients with mild erythema only; this difference was marginally significant, p = 0.055. CONCLUSIONS: This analysis showed a trend towards better local control in patients with severe acute radiation reaction of normal tissue. The data support a recent publication by Dahl and coworkers showing a linkage between acute radiation reaction of normal tissue and tumor response in patients with preoperative radiotherapy for rectal cancer. The correlation between acute normal tissue reaction and local control might be explained by interindividual variations in the intrinsic, genetically determined radiosensitivity. However, local factors might also be involved, e.g. induction of a cytokin cascade in cases of acute reactions in normal tissues.

Adult↗
PubMed1998

Chromosomal in-vitro radiosensitivity of lymphocytes in radiotherapy patients and AT-homozygotes.

BACKGROUND: We investigated the in-vitro radiosensitivity of peripheral blood lymphocytes with a special FISH/CISS-technique. PATIENTS AND METHODS: From October 1993 through April 1996, a total number of 52 cancer patients was enrolled in the study. The tumor sites in these patients were: breast (n = 41), lung (n = 4), head and neck (n = 3) as well as prostate, bladder, rectal cancer and Hodgkin's disease (each n = 1). Twenty-six of them were examined prior to planned radiotherapy (prospective group) and 26 after radiotherapy (retrospective group). Three additional individuals (without cancer or radiotherapy) with proven ataxia telangiectasia (Louis-Bar syndrome, AT-homozygotes) were also investigated and their blood samples served as positive control for radiosensitivity. The clinical radiation response of normal tissue in radiotherapy patients was scored according to the WHO grading system for acute and according to the RTOG grading system for late effects. For to estimate the intrinsic radiosensitivity, blood samples were taken and irradiated in vitro with 0 (control) or 0.7 or 2 Gy with a 6 MV-linear accelerator, standard 48-hour lymphocyte cultures were prepared, chromosomes #1, #2 and #4 were simultaneously labeled with a FISH/CISS-technique and 200 to 1,000 metaphase spreads were scored for chromosomal aberrations. The radiation sensitivity of lymphocytes was expressed as the number of radiation-induced chromosomal breaks per mitosis after 0.7 Gy or 2 Gy corrected for the 0-Gy control value. RESULTS: The frequency of chromosomal breaks/mitosis in the unirradiated control lymphocytes was 0.020 +/- 0.015 in prospective patients who had not yet received radiotherapy. It was significantly higher in retrospective patients (0.264 +/- 0.164 breaks/mitosis) as a result of the previous radiation exposure. The 3 AT-homozygotes showed also an increased number of spontaneous chromosomal breaks (0.084 +/- 0.016 breaks/mitosis), probably resulting from the chromosomal instability in this disease. This figure, however, was significantly lower than in retrospective patients. The number of radiation-induced breaks after in-vitro irradiation was comparable in lymphocytes of patients who showed no normal tissue reaction (n = 11) as compared to those with mild to moderate radiation reaction (n = 32, acute reactions Grade 1 to 2, late reactions Grade 0 to 2). In 9 patients with unexpected severe plus late Grade 3 to 4 reactions, however, a significantly higher number of radiation-induced chromosomal breaks was measured; the highest number was observed in a patient with a radiation myelitis. The 3 AT-homozygotes showed, as expected, an extreme radiosensitivity of their lymphocytes. The number of breaks/mitosis after 0.7 Gy in vitro irradiation of lymphocytes was 0.103 +/- 0.059 in patients with no normal tissue radiation reaction (n = 11), 0.122 +/- 0.146 in the group with mild to moderate radiation reactions Grade 1 to 2 (n = 32), 0.359 + 0.226 in patients with unexpected Grade 3 to 4 normal tissue reactions (n = 9) and 0.550 +/- 0.243 in the 3 AT-homozygotes (p < 0.01, t-test). The difference in lymphocyte radiosensitivity between these 4 groups was also detected after in-vitro irradiation with 2 Gy (0.484 +/- 0.132 vs. 0.535 +/- 0.228 vs. 0.926 +/- 0.349 vs. 1.423 +/- 0.072). CONCLUSIONS: We found a significantly higher number of chromosomal breaks in lymphocytes of patients with severe or extreme radiation reaction of normal tissues as compared to patients with no or only mild to moderate radiation reactions. The radiosensitivity of lymphocytes in these radiosensitive patients was in the range between normal radiosensitivity and the radiosensitivity of AT-homozygotes. Detection of patients with severely enhanced intrinsic radiosensitivity might be possible with this method.

Adult↗
PubMed1998

Primary metastatic (stage IV) Ewing tumor: survival analysis of 171 patients from the EICESS studies. European Intergroup Cooperative Ewing Sarcoma Studies.

BACKGROUND: In the multicenter European Intergroup Cooperative Ewing's Sarcoma Studies, localized Ewing tumors of bone were treated by combination chemotherapy with surgery and/or radiotherapy. Patients with primary metastases (pm-pts) were treated in high risk protocols. PATIENTS AND METHODS: One hundred seventy-seven pm-pts were registered from January 1990 to December 1995, 171 were evaluable for survival analyses. Thirty-six pm-pts received myeloablative megatherapy with stem cell rescue following conventional treatment. Bilateral whole lung irradiation (WLI) was administered in 57 pm-pts with pulmonary involvement. Event-free survival (EFS) rates were estimated by Kaplan-Meier analysis. Prognostic factors were identified by log-rank statistics, Cox procedures and logistic regression. RESULTS: Eighty-nine deaths were recorded by 1 February 1997, EFS four years after diagnosis for all 171 pm-pts was 0.27. EFS for isolated lung metastases was 0.34, for bone/bone marrow (BM) metastases, 0.28, and for combined lung plus bone/BM metastases, 0.14 (P < 0.005). WLI improved outcome in case of isolated pulmonary involvement (0.40 vs. 0.19, P < 0.05). In pm-pts with combined pulmonary/skeletal metastases, intensification by megatherapy and/or WLI improved EFS from 0.00 to 0.27 (P = 0.0001). CONCLUSIONS: EFS four years after diagnosis in patients with disseminated Ewing tumors is 0.27. Whole lung irradiation and megatherapy improve outcome in subgroups of patients with disseminated Ewing tumors is 0.27. Whole lung irradiation and megatherapy improve outcome in subgroups of patients with disseminated Ewing disease.

Adolescent↗
PubMed1998

Ewing's tumors with primary lung metastases: survival analysis of 114 (European Intergroup) Cooperative Ewing's Sarcoma Studies patients.

PURPOSE: To analyze event-free survival (EFS) and prognostic factors in patients who present with Ewing's tumors (ET) of bone and synchronous pulmonary and/or pleural metastases (ppm). PATIENTS AND METHODS: Of 1,270 patients (pts) registered at the continental office of the German/European Intergroup Cooperative Ewing's Sarcoma Studies (CESS81, CESS86, EICESS92), 114 were diagnosed ET with ppm. Patients underwent neoadjuvant therapy and local treatment of the primary tumor. Whole-lung irradiation 15 to 18 Gy was applied to 75 ppm-pts. EFS and 95% confidence intervals (CIs) were estimated according to the Kaplan-Meier method, and prognostic factors were analyzed by log-rank tests and Cox and logistic regression procedures. RESULTS: On November 1, 1997, at a median time under study of 5.9 years, the 5-year EFS was 0.36 (95% CI, 0.26 to 0.46) and the 10-year EFS was 0.30 (95% CI, 0.19 to 0.41). Thirty-seven of 59 (63%) first relapses involved lung and/or pleura, and the lungs were the only site of relapse in 26 of 59 (44%) ppm-pts. Risk factors identified in univariate and multivariate tests were poor response of the primary tumor toward chemotherapy, metastatic lesions in both lungs, and treatment without additional lung irradiation. CONCLUSION: Chemotherapy response of the primary tumor is a prognostic factor in patients with ET with ppm. Strategies of treatment intensification warrant further evaluation.

Adolescent↗
PubMed1998

Relevance of oxygen in radiation oncology. Mechanisms of action, correlation to low hemoglobin levels.

At the beginning of this century Schwarz (1909) and Holthusen (1921) observed the influence of oxygen on the radiosensitivity of cells. In 1951 Hollaender et al. described that E. coli needed 3-fold higher radiation doses when treated under anoxic conditions compared to normoxic conditions. This led to the evaluation of the oxygen enhancement ratio (OER) for photons (X-rays), neutrons and heavy ions. It was found that the OER for conventional radiation therapy (RT) with photons is much higher (about 3) than the OER for neutron-RT (only 1.5) or heavy ions. According to a hypothesis free radicals which are produced by radiation are fixed in the presence of oxygen. Radicals are interacting with DNA, macromolecules and membranes. The DNA lesion can be followed by cell death. There is some evidence that tumor cells respond to hypoxia with the expression of a variety of genes coding for oxygen regulated proteins such as c-jun, VEGF or p53. Hypoxia also enhances the genetic instability of tumor cells. Oxygen tensions in malignant tumors can be determined under clinical routine conditions by using a computerized polarographic needle electrode system (Eppendorf, Hamburg, Germany). Several studies in the past years showed that tumors are in general more hypoxic than the surrounding normal tissue and that a marked variability of intra- as well as intertumoral pO2 values exist (for review see Vaupel and Höckel 1998). Moreover, it has been shown in different tumor entities that the oxygenation status influences the local control rate and overall survival. Furthermore, the oxygenation status obtained at one site (primary) is significantly related at other sites (lymph node metastases) in patients with squamous cell carcinoma of the head and neck (SCCHN). In addition, there is a significant correlation between hemoglobin level and tumor oxygenation in patients with SCCHN. There is some evidence that the oxygenation status can be improved by the correction of a low hemoglobin level and consequently, the curative chance might rise.

Cell Hypoxia↗
PubMed1997

[Intratumor pO2, S-phase fraction and p53 status in cervix carcinomas].

PURPOSE: Investigation whether tumor tissue oxygenation is influenced by proliferation or p53-status in cervical cancers. MATERIAL AND METHODS: From April 1995 through December 1996, 28 patients with locally advanced cervical cancers (age 36 to 78 years; FIGO stages: 10 patients IIB, 16 patients IIIB, 2 patients IVA) underwent intratumoral measurement of pO2 prior to definitive radiotherapy. The histological specimens were examined for grading and quantitative immunohistological expression of the MIB-antigen and p53-protein. Proliferation was estimated by measuring the S-phase fraction with flow cytometry. RESULTS: The median pO2-values showed a broad variation from 2.2 through 60.4 mm Hg, median 19.7 mm Hg. The S-phase fraction varied from 4.2 through 34.2% (median 11.6%), MIB-positive cells from 20 through 100% (median 74%), and immunohistologically p53-positive cells from 0 through 95% (median 2%). The patients were divided in 2 groups according to the pretreatment pO2. Tumors with a pO2 above the median had a lower S-phase fraction than tumors with a pO2 below the median, 10.4 +/- 3.8% versus 16.3 +/- 5.5%, p < 0.02. MIB and p53 were not different in both groups (MIB: 68.1 +/- 27.7% versus 75.0 +/- 18.4%, p = 0.1; p53: 26.4 +/- 38.5% versus 18.1 +/- 19.8%, n. s.). Grade of differentiation and FIGO stage had no impact on pO2. CONCLUSION: Locally advanced cervical cancers with a poor oxygenation have a higher proliferative activity. Tumor proliferation may play a causative role for the development of hypoxia as suspected from radiobiological theories.

Adult↗