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S Mose

Publications and source records attributed to S Mose.

29 records · Page 2Linked to original sources

In vivo dose increase in the presence of dental alloys during 60Co-gamma-ray therapy of the oral cavity.

During irradiation of the mouth cavity, dental metallic materials emit secondary electrons and thus increase the applied radiation dose in their vicinity. Therefore, local destruction of the mucous membrane contacting metallic dental crowns and fillings may be observed. Available data on this dose increase are based on measurements with beam arrangements perpendicular to the metallic surface. Since the dose modification depends on the beam direction in relation to specimen surface, a reliable prediction of dose modification in the close vicinity of dental caps on fillings under complex beam arrangements, as applied in the irradiation of head and neck region from the published data is not possible. Therefore, we measured dose increase in the immediate surrounding of metallic dental material using thermoluminescence dosimetry on the phantom and during routinely applied 60Co gamma ray therapy. Phantom measurements were carried out using several oblique irradiation angles and rotational therapy. In vivo measurements were carried out at alloy specimens containing gold, palladium, and amalgam in six patients and at permanently fixed golden teeth in five patients. In vivo, the following relative dose increase values according to a simultaneously measured reference value were obtained at the surface of different dental materials: 61% for fixed golden caps. 68% for the specimen containing gold, 33% for the specimen of palladium and 61% for the specimen of amalgam. The measured dose increases due to metallic dental material during routinely applied external 60Co beam irradiation are lower compared with those of perpendicular beam arrangements. Although, the extent of dose modification is less than expected, we still advocate protection of the oral mucosa to prevent painful lesion spots.

Cobalt Radioisotopes↗

[The assessment of solitary osteolytic bone lesions in breast carcinoma. A special case report].

BACKGROUND: Solitary bone lesions occurring 10 and more years after primary known breast cancer are usually declared as metastases of this tumor. However, this assumption is not correct. In such cases the probability of a second malignancy has to be concerned as well. PATIENTS AND METHODS: We report the case of a 77-year-old woman, in whom 18 years after primary breast cancer therapy an osteolysis in her right radius occurred. The treatment planning was aggravated by the diagnostic classification of this lesion. RESULTS: The diagnostical differentiation between bone metastases of the known breast cancer or another extramammary solid cancer and a primary tumor of the bone was not possible by clinical and blood examination, X-ray and MRT-imaging. As the diagnostically decisive step a biopsy was performed proving a metastasis of the known breast cancer. CONCLUSIONS: This case pointed out that the diagnostical classification of a solitary osseous lesion exclusively based on anamnestically known primary cancer treated long times ago is not permissible. Before therapeutic decision is correctly fixed, detailed diagnostic examinations according to basic oncological rules are conclusively required.

Aged↗

[Radiation load on the skin using a silicone-coated polyamide wound dressing during photon and electron radiotherapy].

BACKGROUND: Silicone-coated polyamide wound dressing is frequently used for the supportive treatment in patients with radiation induced skin lesions. The use of this kind of dressing during radiotherapy with high energy beams shifts the dose built-up effect towards the skin surface. Thus the dose delivered to the skin increases. The present work quantifies changes of the skin dose by a commercial silicon-coated polyamide wound dressing. The dependence on the beam quality and on different treatment techniques is investigated. PATIENTS AND METHODS: Measurements were performed with photon (60Co, 6 MV, 42 MV) and electron (7 MeV, 20 MeV, 40 MeV) beams using thin LiF thermoluminescence dosimeters (TLD) in a perspex phantom. The beams were directed perpendicularly to the phantom surface. For 60Co and 6 MV photon beams the skin dose was evaluated in vivo at different beam arrangements and at a given reference dose. RESULTS: For 60Co, 6 MV and 42 MV photon beams wound dressing caused a dose increase on the surface of the perspex phantom by a factor of 1.65, 1.39 and 1.33 respectively. Using oblique or rotational techniques for 60Co and 6 MV photon irradiation the wound dressing increased the skin dose but less compared to perpendicular beam direction. For electron beams the skin dose is relatively high (from 84% to 92%) and an increase by a dressing has no clinical relevance (factor 1.03 to 1.05). CONCLUSION: The silicone-coated polyamide wound dressing causes no relevant skin dose increase during radiation treatment with electron beams and can be left on the skin during irradiation. During radiation treatment with photon beams like 60Co and 6 MV the protective procedure should be adapted to skin changes, in case of strong skin reactions a removal during the time of irradiation should be considered.

Bandages↗

[The in-vivo determination of dosage intensification due to dental alloys in the therapeutic irradiation of the oral cavity].

BACKGROUND: In the course of therapeutic irradiation of regions in the mouth cavity dosage increase due to the emission of secondary electrons in the vicinity of dental materials can be observed. This could induce local destruction of the mucous membrane in contact with metallic dental crowns and fillings. As at now, only rough estimates of this dosage increase could be made with the help of measurements carried out with models. PATIENTS AND METHODS: The degree of dosage increase in the immediate surrounding of metallic dental material was measured in an in-vivo study during therapeutic irradiation with 60Co gamma rays in the area of mouth cavity of 11 patients. Measurements were carried out by thermoluminescent dosimetry at permanently fixed golden teeth and alloy specimens containing gold and palladium and amalgam. RESULTS: The following relative dosage values according to a simultaneously measured reference value were measured at the surface of the different dental materials: 161% near fixed golden caps, 168% near the specimen containing gold in a high percentage, 133% near the specimen of palladium and 161% near the specimen of amalgam. CONCLUSION: The in vivo measured dosage increases due to metallic dental prosthesis are less than values obtained using back scatter arrangements for irradiating phantoms. Despite this, they could be of clinical relevance. Thus the usage of a mucous membrane protection during irradiation with 60Co, as a means of preventing local lesions of the oral mucosa, due to dental alloys within the treatment volume remains inevitable.

Cobalt Radioisotopes↗

[Immunoglobulin for prevention of radiogenic mucositis].

Among various therapies administered during radiation-induced mucositis, treatment with immunoglobulin has proven clinically successful. In this study the efficacy of prophylactic applications of immunoglobulin was investigated from January 1992 through August 1993. Forty-two patients with histologically-proven head and neck cancer were given postoperative radiation treatment. In cases with macroscopic tumor residues or inoperability, combined radio-chemotherapy was given. This included 51.3 Gy at 1.9 Gy 5x/week, boosted to 10-26 Gy at 2 Gy 5x/week and carboplatin 60 mg/m2 at days 1-5 and 29-33. Panthenol (4x10 ml/day) and nystatin (4 x 1 ml/day) were given to 20 patients as prophylactic treatment for mucositis. Twenty-two subsequent patients also received intramuscular 800 mg (5 ml) human immunoglobulin (1x/week). According to the Seegenschmiedt/Sauer classification the extent of mucositis was determined 3x/week. Comparison of the distribution of maximal mucositis revealed a slightly more severe mucosal reaction in the control group (n.s.). Analysis of the mean degree of mucositis in both groups demonstrated statistically significant differences (p = 0.031) related to the whole collective and patients receiving concomitant chemotherapy while no effect of immunoglobulin was found in patients treated by radiation alone. In the immunoglobulin-treated-group, the time from the beginning of therapy to the first interruption was prolonged 5 days (37.5 +/- 13.1 vs. 42.7 +/- 13.3 days), but this difference was not significant. Although prophylactic application of immunoglobulin seemed to lower the degree of radiation-induced mucositis, this effect was less significant when compared to the immunoglobulin given in a therapeutic manner.

Adult↗

[The prognosis of bilateral breast carcinoma compared to unilateral breast tumor. 5- and 10-year follow-ups].

PURPOSE: A review of published data does not provide a certainty whether survival rates are comparable or worse in women with bilateral breast cancer versus patients with an unilateral tumor. Therefore results of therapy in one-sided and both-sided breast cancer were retrospectively analysed. PATIENTS AND METHODS: In a period from 1977 to 1982 (follow-up 5 to 12 years) 531 breast cancer patients with T1-4 N0-3 M0 tumors were treated with mastectomy (n = 416) and breast conserving therapy (n = 115). Postoperative radiotherapy was performed in all patients (50 Gy, 2 Gy/day 5 times/weekly; chest wall/breast and regional lymph nodes). Patients with positive lymph nodes received chemotherapy. Forty patients developed bilateral breast cancer (simultaneous n = 10, metachronous n = 30) that was treated by mastectomy (n = 28) and conservative surgery (n = 12), respectively, followed by radiotherapy in 26 women. RESULTS: Five- and 10-year survival was 74% and 56% in unilateral affected women. In 83% and 67% there were no metastases, respectively. Incidence of metastases was 27.9%. In bilateral breast cancer group survival rates were 85% and 59% and without evidence of metastases 87% and 60%, respectively. Distant disease was diagnosed in 35%. Differences between the 2 groups were statistically not significant. Whereas in time of follow-up 11% of unilateral cancer locally failed in bilateral cancer patients recurrences of the first and second tumor were seen in 20% and 10%, respectively. CONCLUSIONS: Survival of patients with bilateral breast cancer is not significantly decreased compared with unilateral disease although in patients with both-sided carcinoma local recurrences and metastases seem to occur more frequently.

Adult↗

[Value of SPECT-immunoscintigraphy in radiation treatment planning for patients with squamous cell carcinomas in the head and neck area].

PURPOSE: Introduction of monoclonal antibodies (immunoscintigraphy) has significantly extended the diagnostic spectrum of nuclear medicine in oncology. The detection rate of this new method in patients bearing squamous cell carcinoma of head and neck is better compared to computed tomography and magnetic resonance imaging. In a prospective study, we examined whether immunoscintigraphy in addition to other imaging procedures is able to provide additional diagnostic information for radiation treatment planning.

Antibodies, Monoclonal↗

[The value of conventionally fractionated radiotherapy in the local treatment of HIV-related Kaposi's sarcoma].

BACKGROUND: During the course of AIDS, 25 to 44% of homosexual patients infected with the human immunodeficiency virus develop Kaposi's sarcoma. Main manifestation is the skin. Response rates of 80 to 100% can be achieved with total dosage up to 50 Gy. Nevertheless, remissions can also be attained with 20 Gy of fractionated radiotherapy. As clinical data on low dose conventional fractionated radiotherapy are insufficient we analysed the response rates of an overall dose of 20 Gy in conventional fractionation. PATIENTS AND METHODS: From June 1991 to June 1993, 43 patients with 111 HIV-associated Kaposi's sarcoma of the skin or oral cavity were treated. Lesions were irradiated with 5 to 12 MeV electrons or 60Co gamma-rays. The fractionation scheme was 5 times 2 Gy/week for skin and endoral lesions with a total reference dosage of up to 20 Gy. Side effects were assessed during therapy and the therapeutic result 6 weeks after end of treatment. RESULTS: Thirty-eight out of 111 lesions were judged as complete response (CR) (34%), 61/111 as partial response (PR) (55%) and 12/111 were judged as no change (NC) (11%). Overall response (CR + PR) was 89%. Two patients with lesions of oral cavity suffered from RTOG grade-IV mucositis after 10 and 14 Gy. In 71/106 skin lesions (67%), radiation induced RTOG grade-1 reactions were observed. CONCLUSION: In patients with HIV associated Kaposi's sarcoma effective palliation can be achieved by means of radiotherapy with an overall dose of 20 Gy in conventional fractionation. Yet, the fraction of patients with complete responses is with 34 to 47% lower compared with doses above 20 Gy (66 to 100%). With reference to the reported data our results point to a dose-response relationship for Kaposi's sarcoma. Therefore higher total reference doses, e.g. 30 Gy with weekly 5 times 2 Gy or 24 Gy with 5 times 1.6 Gy for mucous lesions, respectively, are suggested as by this mean the complete response rate can be doubled.

Adult↗

Radiation enhancement of gemcitabine in two human squamous cell carcinoma cell lines.

BACKGROUND: Gemcitabine (dFdC) is a new nucleoside analogue with promising activity in different solid tumors. We investigated whether dFdC enhances the effect of irradiation in human squamous carcinoma cells of the oropharynx (#4197) and of the uterine cervix (HeLa) with special regard to the time-dose-relationship concerning dFdC and the dependence upon the timing of irradiation. MATERIALS AND METHODS: Under standardized conditions monolayers of cells were exposed to various dFdC concentrations (0.003-10 mumol/l) for different times (4-24 h). Irradiation (0-6 Gy) followed immediately or 12 h after dFdC exposure (0.003-0.03 mumol/l; 4-24 h). RESULTS: The cytotoxic effect of dFdC depends on its concentration and the exposure duration. Exposed to non and/or slightly cytotoxic concentrations (> or = 0.003-0.03 mumol/l) for 4, 8, 16 and 24 h and followed by immediate irradiation the radiation enhancement ratio (RER) is 1.03-1.67 in #4197 cells and 1.04-2.47 in HeLa cells, respectively. Irradiated 12 h after 24 h exposure (dFdC 0.01-0.03 mumol/l) the RER is reduced to 1.10-1.17 (#4197) and 1.18-1.72 (HeLa). CONCLUSIONS: Depending on the drug concentration, exposure duration, and timing of irradiation, dFdC enhances the irradiation effect on human squamous cell carcinoma cell lines (#4197, HeLa).

Antimetabolites, Antineoplastic↗

Influence of radiotherapy on psychological health in breast cancer patients after breast conserving surgery.

BACKGROUND: The purpose of this study was the evaluation of the radiotherapy-induced psychological distress of patients and changes in psychological health during radiotherapy (RT). PATIENTS AND METHODS: 53 breast cancer patients undergoing irradiation after breast conserving surgery participated in this study. In the beginning and at the end of radiotherapy they answered a questionnaire asking for coping strategies, psychological distress with regard to irradiation and influence of surroundings. RESULTS: 92% stated to be well informed about radiotherapy. Coping strategies in order of importance: Talking to physician (94%) or partner (84%), 81% try to distract themselves, 56% repress thoughts about radiotherapy. 40% were anxious about RT and expected side effects (54%). At the end of therapy anxiety was reduced: 77% were anxious only initially or never. CONCLUSIONS: Patients are very interested in information about RT. Their experience of radiotherapy was more positive than initially expected. The relation to medical staff plays an important part in the reduction of irradiation-related psychological distress.

Anxiety↗