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N Schwegler

Publications and source records attributed to N Schwegler.

At least 19 recordsLinked to original sources
PubMed2003

[Correlation of risk factors with the efficacy of applied therapies by breast conserving procedure in breast cancer].

1007 cases of female breast cancer patients treated with breast conserving surgery and subsequently irradiation with a median dose of 66 (50-80) Gy including boost with tangential high voltage photon beams. 34.6% (348/1007) received no further therapies, 53.4% (538/1007) Tamoxifen, 26% (262/1007) an adjuvant chemotherapy +/- Tamoxifen. All tumors were classified on the basis of the pathologic-anatomical spreading: 70.7% (712/1007) pT1a-c, 27.4% (276/1007) pT2. 1.9% (19/1007) pT3-4 due to the refusal of mastectomy or an error in the preoperative diagnosis. 32.5% (327/1007) showed proven axillary metastases, of which 26.3% (86/327) > or = 4 LN+. Median age 56 (23-92) years. The local relapse rate after a median follow-up of 70 (12-264) months amounted to 5.9% (59/1007). Distant metastases were registered in 11.5% (116/1007). A total of 8.8% (89/1007) died as consequence of breast cancer, 3.2% (32/1007) of other causes. In 82.6% (816/988) of the pT1/pT2 tumors the resection area had been described. In 29.8% (156/524) in the resected parts there were found rests of tumors. The LRFS falls from 94% to 82% and by remained R1 (26/524) to 47%. Correlation likewise the DMFS, which sanks from 81% to 68% respectively to 63%. We expect a second wave of metastases like the situation by local relapses. Often the R1-resection was connected with other histological high risk factors as multifocality/-centricity, necrosis or vascular invasion. If one divides the patient case sample into a first group with special risk factors (< or = 40 years of age, > or = 4 positive axillary lymph nodes, vascular invasion), and a second which exhibited none of these components, the first group had a 23-26% lower disease free survival rate. Amazing is the fact that, subsequent to a lumpectomy and irradiation, the use or non use of Tamoxifen and/or cytostatics was without proven statistical significance. The evaluation was conceived and implemented more than 20 years ago, and documentation was continuously collected ever since. We're aware of the lack of randomization, but there are less the randomized studies than rather its transformations respectively the daily routine who will decide about life and death. However, evaluations of this data by medical oncologists would, on the one hand, make it possible to better assess the importance of the available data and our results, and, on the other hand, clarify the clinical value of partially and/or completely applied medical treatments.

Adult↗
PubMed2002

[Breast carcinoma: value of adjuvant therapy after mastectomy? Overview of personal results over > or = 20 years].

Analysis of 626 consecutive locoregional postoperative irradiated patients after mastectomy. 49.5% (310/626) were without further therapies, 32.8% (205/626) received TAM and 17.7% (111/626) an adjuvant chemotherapy +/- TAM. All tumours were classified on the basis of the pathologic-anatomical spreading. Median age 59 (25-91) years, follow-up 180 (60-265) months. Local relapses 7.1%, distant metastases 40.4%, death as consequence of breast cancer 35.6%, in 20.3% death of other causes. Cause specific survival (CSS) by negative axilla in 76%, by 1 to 3 LN+ metastases in 55% and by > or = LN+ in 30%. On the basis of the final results, lymphnode status, vascular invasion and initial tumor size have been the most important risk factors of prognostic relevance. Their rate of local relapses have been twice to six times as high, the distant metastasis 1.5 to 2 times more frequent. Immense differences too in comparing the CSS after 20 years: high risk collective 26 to 47%, low risk 65 to 72%. No statistical difference has shown in the low risk collective between the therapy groups. As referred back to the initial axillary status, 39.6% (248/626) have been without positive LN at the time of mastectomy. 76.2% (189/248) have remaind without distant metastases (DM), in 78.4% (149/190) without adjuvant therapy after locoregional irradiation. In 60.4% (378/626) the axilla was attacked. 48.7% (184/378) remained without distant metastases. 19.6% (36/184) with chemotherapy, 49.4% (91/184) with TAM and 31% (57/184) without supplemented systemic therapies. With 1 to 3 LN+ 58.4% (108/185) neither clinical nor radiological dissemination proven. It may be due to the efficiency of chemotherapy and TAM that only in 38.2% (13/34) respectively in 34.3% (23/67) distant metastases have been proven. In contrary after > or = 4 LN+ the chemotherapy-group has had 76.2% (48/63) and by combination with vascular invasion 85.2% (23/27) distant metastases. An opposite effect cannot be excluded. A positive axilla may but doesn't have to be a harbinger of tumor generalisation, since on third has remained without distant metastases despite of the lack of adjuvant therapies after locoregional irradiation. Is it possible a consequence of the irradiation too? No side effects of importance: Absence of plexopathies, no cardiotoxicity, 0.8% rib-necrosis after high dose irradiation as a consequence of R1-resections. There are no reasons for a renunciation of postmastectomy irradiation because of its secondary effects.

Adult↗
PubMed1999

[Inoperable non-small-cell bronchial carcinoma: macroscopic and microscopic tumor behavior during and after radiotherapy with curative intent].

The supervision of the efficacy of therapy with curative aim in inoperable NSCLC focus on clinical and radiological parameters and the survival rate. But the decision about the local tumour elimination lies in the microscopic area, which cannot be controlled neither by laboratory tests nor by radiological examinations. About twenty years ago with support of our pneumologist we carried out bronchoscopies and biopsies depending on the applied radiation dose. It was our intention to take the remission noted by endoscopy as measure for the reaction of the whole irradiated target volume. The bronchoscopies and biopsies were provided at dose levels of 60 and 80 Gy. 90.9% (340/374) of repeated bronchoscopies were realized after a dose of 60 to 80 Gy. The analysis covers 253 bronchoscopies before and 374 between or after radiotherapy with 623 histological or cytological examinations on a total of 253 patients. At the begin of the radiotherapy 50.2% (127/253) had tumour between trachea and a lobar bronchus, after 60 Gy only 13% and after 80 Gy still 1.2% (1/81) had tumour in this area. The macroscopical tumour elimination rose from 41.4% (80/193) after 60 Gy to 79.3% (65/82) after 80 Gy. In contrast and unexpectedly the microscopic negativity decreased from 73.4% (141/192) to 71.6% (58/82). Partially this result is a consequence of the fact that "necrosis" may be either a part of an untreated malignoma or an effect of an irradiation. The combination of macro- and microscopic tumour elimination rose from 20.5% (7/34) after a dose of 60 Gy to 64% (16/25) after total doses of 80 Gy. Only combined negativity had a consequence for local relapse free survival (p = 0.034) and overall survival (p = 0.0002) in comparison with the patients with persistent macro- and/or microscopically detected endoluminal tumour at the final bronchoscopy. The assessment of endoluminal tumour regression as part of the whole irradiated malignoma permits conclusions about the total dose needed. This is a new approach providing at least more local security without augmentation of side effects in comparison with the conventional guidelines.

Adult↗
PubMed1999

[Breast-preserving therapy: 19 years of monoinstitutional experience and results].

After conservative surgery 491 women with unilateral, invasive breast cancer were irradiated with a median dose of 50 Gy (ICRU-point) for the whole breast and an additional boost of 20 Gy respectively. The mean (median) follow-up was 69.7 (60) months with a range from 24 to 221 months. The surgical interventions were called tumorectomy in 16.1%, lumpectomy in 63.5% and quadrantectomy in 20.4%. The tumour size was classified in 73.5% (361/491) as pT1 and in 23.5% (117/491) as pT2. 2.7% were > pT2-tumours. A dissection of the axilla (473/491) recovered at the median 16 lymph nodes (0 to 48), of whom on an average 3.7 (1 to 46) contained metastases. According to Kaplan-Meier the five and ten year survival rates yielded the following respective end-points: local relapse free 94.5% and 89.2%, free of distant metastases 84.5% and 75.6%, disease free 80.7% and 69.4%, cause specific 90.3% and 79.1% and overall survival 89.5% and 76.4%. In patients with positive margins local relapses were seen in 14.6% and distant metastases in 26.8%, versus 5.7% and 16.1% respectively for the whole cohort. If even a re-excision couldn't get clear margins, 27.3% of these patients developed a local failure and 45.5% distant metastases. In contrast, the corresponding data for a re-excision specimen with residual tumour but negative margins were 9.9% and 12.3%. Possibly, the ability to achieve clear margins is not only a local problem, but an expression of the tumour biology. Another risk factor seems to be tumour necrosis: 16.2% local and 35% distant relapses occurred compared to 4.8% and 14.5% in patients without this histological feature. All acquired data are listed in Table 2. Their statistical relevance according to the log rank test is given in Table 3. No significance was seen for adjuvant systemic treatments. Both groups of patients were, however, not very well balanced with respect to conventional risk factors.

Adult↗
PubMed1999

[The gonadal loading during the irradiation of lymph outflow in operated seminomas. In-vivo dosimetry].

BACKGROUND: This article should demonstrate the problems concerning gonadal dose in seminoma patients, the impact of shielding and possible consequences for therapy and advising of patients with desire to have children. PATIENTS AND METHOD: Since November 1993 gonadal doses of 43 patients (Stage I/II, Royal Marsden) have been determined in 80 measurements with 2 ionization chambers on the ipsi- and contralateral side of the remaining testicle. The patients were all treated with ap/pa "hockey-stick"-shaped fields on a 6 MV linear accelerator. With single doses of 1.8 Gy in midplane, total doses of 34.2 Gy were applied in 13, and 30.6 Gy in 30 men. Protection was used in 33 patients, 6 times with conventional shielding, later plus an additional clam-shell from ap. The results of 22 measurements on 6 men with and without protection are of special interest. In 25 patients a sperm analysis before radiotherapy was conducted. RESULTS: Before the beginning of radiotherapy (RT) 56% of available patients have shown an impaired spermatogenesis. The mean gonadal doses were 2.4% of midplane dose-MD (4.8 cGy), 1.8% MD (3.2 cGy) and 1% MD (1.8 cGy) per fraction for patients without (n-patients = 10, m-measurements = 15), with conventional (n = 6, m = 7), and additional clam-shell shielding (n = 33, m = 58). The corresponding median values were 2.1% (SD 1.07), 1.7% (SD 0.28) and 1% (SD 0.41) of midplane dose (Table 1, Figure 1). According to direct comparisons, a dose reduction of about half can be expected in most cases (Figure 2). Mean dose fluctuations of 11.6% (median 10%) have to be taken into account. CONCLUSION: Effective shielding can diminish gonadal dose in seminoma patients to about 1% of midplane and gives a good possibility of taking the maintenance of fertility and the desire to have children into account (Table 2). The application should be considered especially for patients with impaired spermatogenesis before RT. Eventual fluctuations induced us to determine the gonadal dose 3 times per patient in direct measurements (Table 3).

Adult↗
PubMed1997

[Lung cancer--hopelessness in inoperability? A 10-year follow-up].

BACKGROUND: According to reports of Durrant et al. [19] and Berry et al. [5] it was concluded that non-operable non-small cell lung tumors cannot be cured. In this consequence initiation of radiotherapy was fixed at the beginning of symptoms. However, long-time survivors in our follow-up lead us to analyse not only quality of life and secondary therapeutic effects but also this special group with the results of the whole collective treated in the same period of interest. PATIENTS AND METHODS: Between 1.1. 1981 and 31. 12. 1983 a number of 169 patients had been recommended for locoregional radiotherapy treatment of lung cancer; 145 patients received at least 50 Gy, 134 out of them 60 Gy or more. Men/female ratio was 137:8, median age was 65 (36 to 88) years. Classified according to the TN-stage there were 59 patients in T1-4 N0 and 86 patients in T1-4 N1-3 M0. Histologically: 98 squamous cell carcinomas, 23 adenocarcinomas, 9 large cell carcinomas and 15 specimens mixed from the named subgroup or rare histologies. Treatment concept including repetition of bronchoscopic evaluation after 60 Gy was prospectively discussed and fixed with our pneumologist. Radiation dose was given with a shrinking-field technique to mediastinum and primary. In case of macroscopically or microscopically persistence of tumor we continued radiation dose up to 80 Gy. Radiotherapy was not followed by chemotherapy. A telecobalt unit has been used for treatment due to the lack of high-voltage linear accelerators. In absence of a computer assisted planning system-a problem in most of the radiotherapeutic centers in this time-dose calculation was done by central beam planning of ICRU-point in the middle of the tumor respectively the center of target volume on the base of a cross section. Usually there was used a 3-field plan ap/pa opposite and an oblique field with an angle of 30 degrees from the ipsilateral back or ventral side, depending on the position of the tumor. Spinal cord was shielded to avoid a dose-more than 36 to 42 Gy. The longer distance and higher weightiness of the oblique fields had as consequence lung fibrosis in the irradiated lung area and a considerable higher maximal dose situated in the soft tissue and skin often followed by strong indurations in this area 1 to 3 years after radiation therapy without further limitations of quality of life. RESULTS: From 145 patients with non-small cell lung cancer 64.1% (93/145) survived 6 months, 42.8% (62/145) 1 year, 19.3% (28/145) 2 years and 7.6% (11/145) 5 and 4.8 (7/145) more than 10 years. According to TN-stages T1-4 N0 collective had a survival rate of 67.8% (40/59) after half a year, 50.8% (30/59) after 1 year, 23.7% (14/59) after 2 and 11.9% (7/59) after 5 years. Treatment results by patients with positive lymph nodes T1-4 N1-3 after the same intervals are: 61.6% (53/86), 37.2% (32/86), 16.2% (14/86) respectively 4.7% (4/86). In the period 5 to 10 years after irradiation 4 patients died, 1 with local relapse, 2 with contralateral lung cancer-ipsilateral region was endoscopically and histologically free of tumor- and 1 patient in consequence of heart insufficiency of several years. Seven patients are still alive after 13 to 16 years. There is no sign of tumor in this group or any effects limitating their quality of life. Twenty-four patients received less than 50 Gy. All patients but 2 did not survive 6 months. One patient survived half a year and 1 patient 2 years. CONCLUSIONS: The reported treatment results in a period with modest technological possibilities, a telecobalt unit, should encourage to a curative intention, when dissemination cannot be proved. If lung cancer is limited to the primary region with or without lymph node metastases the possibility of tumor elimination is small but feasible. If inoperable lung cancer is not curable, this mostly is not due to inability of locoregional radiotherapy, but rather can be seen as a lack of reliable and permanent elimination or prevention of

Adenocarcinoma↗
PubMed1996

[Breast-preserving treatment of breast carcinoma: analysis of surgical, pathologic-anatomic and radiotherapeutic data of 291 cases].

291 breast cancer patients treated with conserving surgery and subsequent locoregional irradiation were studied. The method of surgery consisted of 200 lumpectomies, 76 quadrantectomies and 15 with either a wide excision or with an atypical resection. In at least 42.6% (124 out of 291), the tumor had been within 10 mm distance to the margin of resected specimen, in 13.4% (39 out of 291) the tumor even reached the border. In the other reports, a numerical description of the distance to the margins was not given. Postoperative radiotherapy was applied with 50 Gy cobalt-60/6-MeV photons to include the whole breast. A boost of tangentially opposed photon beams was added, replacing a technique with direct electron fields used in an earlier period during three years. The supraclavicular fossa received 46 Gy, the retrosternal pathway was covered with 45 to 50 Gy photons/electrons. Locoregional failure after an average observation time of 39.5 months was 4.5% (13 out of 291), within the target volume 3.8% (11 out of 291. The 39 cases on which the tumor reached the margin of resection, 92.3% (36 out of 39) remained free of recurrences. With a tumor-free resection line but a maximal distance of 10 mm, one recurrence (1.2% or 1 out of 85) was found. With the application of tangential photon beams to the tumor bed, which technically allowed sparing skin parts but also slightly reduced daily doses, the incidence of telangiectasis could be lowered to 2.5%. An anatomical was model was constructed to resemble a patient in the treatment position. Dosimeters were implanted and verified by computed tomography. Measurements of the radiation fields were performed within the breast, the lung and along the mammaria-interna chain. Minimal angle changes of 5 degrees decreased the retrosternal dose down with the amount of 56.5%, 10 degrees of 75% and 15 degrees of 85.7%. In contrast, moving the central axis medially by 1 cm and 2 cm increased the lung dose 2.2 and 4.4 times, respectively, whereas the dose within the breast remained almost equal. This emphasizes the importance of identical positioning, which must be realized 25 to 35 times throughout the course of therapy, often with different staff! Precision and consistent positioning are the main priorities. If these goals are achieved, lumpectomy with subsequent high-dose radiotherapy respecting cosmetics provides patients with excellent quality of life.

Adult↗
PubMed1996

[Local efficiency of percutaneous radiotherapy in lung cancer. Analysis of 215 repeated bronchoscopies in relation to applied radiation dosage].

PURPOSE: During a locoregional radiotherapy with curative attempts of lung cancer patients bronchoscopic examinations with biopsies and/or cytologic lavages were repeated to assess the accuracy of limiting the total dose to 60 Gy. In order of the applied dose macroscopic changements of the endoluminal tumor and microscopic elimination should be made out. The correlation between macro- and microscopical regression should allow a statement about reliability of single results. The clinical course and a conventional thoracic X-ray examination seemed to be a to large-meshed screen to evaluate the effect at the end of therapy. The aim was to improve the criterias of success and to adapt and optimize the radiation dose individually. PATIENTS AND METHODS: The prospective, together with the pneumologists, defined treatment concept included the repetition of bronchoscopic evaluations after the application of 60 Gy and 80 Gy. These radiation doses from 60 Gy up to 80 Gy have been given with a shrinking-field technique to the mediastinum and the primary. In order to record statistically the optical tumor changements we were urged to create a so-called bT-score. The structure of this score was orientated towards the periphery of the tracheobronchial tree. RESULTS: Hundred and forty-four patients with endoscopically and histologically verified bronchogenic carcinomas were treated. On the subjects 215 re-bronchoscopies accomplished with biopsies were performed and allowed to analyze the macro- and microscopical behavior under treatment. A histological/cytological elimination of tumor was achieved after 60 Gy in 35.1%, after 80 Gy in 62.3%. Macroscopically no tumor was visible after 60 Gy in 43.6%, after 80 Gy in 82%. A correlation between identical micro- and macroscopical observations was only seen in 61%, respectively in 71%. CONCLUSIONS: The escalation of the radiation dose from 60 Gy up to 80 Gy with shrinked fields could increase the local tumor sterilization rate by 1.8 times from 35.1% to 62.3%. The refining and completion of usually known parameters by endoscopical and histological examinations seems to be an acceptable way to define individual radiation doses. The quality of the performed therapy can be better determined. A predestination of the total dose to a limit of 60 Gy does not ensure a macro- and microscopical elimination of the tumor and may be inferior to an individually adaptation of the dose.

Adenocarcinoma↗
PubMed1995

[Radiotherapy of malignant lymphomas of the brain: Radiologic behavior in relation to radiation dose and volume].

PURPOSE: During the radiotherapy of malignant CNS-lymphomas computertomographic controls were performed as a routine. The radiologic results should give a base to define the total dose. The aim was to determine the value of such individual parameters. PATIENTS AND METHODS: Fourteen years ago the prospectively defined treatment concept included a parallel opposed whole brain irradiation slowly increasing with 1 x 1.0 Gy, 1 x 1.5 Gy, 1 x 2.0 Gy, then 10 x 3 Gy, followed by a radiological control and whenever possible a boost to the initially involved region with 7 to 10 x 2 Gy. RESULTS: From 1. 1. 1979 to 31. 12. 1993 28 patients with a malignant non-Hodgkin-lymphoma of the brain have been seen at the state hospital in Aarau. Fifteen cases suffered from a primary involvement of the brain, 13 showed a secondary manifestation. 20/28 (71%) presented radiologically, cytologically or at autopsy as multifocal disease. Histologic examination mainly detected intermediate or high-grade lymphomas. 25 patients have been irradiated. In 4 out of them the radiation concept couldn't be realized. CT-results were as follows: after 30 to 40 Gy: CR = 2/21 (9.5%); after 45 to 55 Gy: CR = 10/19 (53%); after 1 to 3 months: CR = 12/15 (80%). Nine local relapses occurred, 3 out of them regrowed multifocally and therefore were detected also within the boost region. Six recurrences were outside in the lower dosed areas. No severe side effects have been observed. CONCLUSIONS: Most of the tumors disappeared radiologically not before 1 to 3 months after radiation. Recurrences are mainly seen in the lower dosed region. The incidence and the localisation of the recurrences give some reason to the idea, that the computertomography of these tumors does not detect properly there prior extensions.

Brain Neoplasms↗
PubMed1993

[Endoscopic, biopsy and functional results in irradiated esophageal carcinoma].

83 patients of average age 64 (36-86) years with esophageal cancer were irradiated according to a prospectively defined treatment concept. After 60 Gy, re-endoscopy with biopsy was scheduled. If the tumor was still macro- or microscopically described, a boost to 70 Gy was given. During consistent weekly monitoring particular attention was focused on patients' ability to feed themselves. While initially only 7.2% could swallow solid food, by the end 84% of patients with a radiation dose of 60 Gy or more reported normal daily eating. Patients in whom the tumor was no longer present endoscopically or histologically survived four times longer (13.5 months) than those with persistent malignoma.

Adenocarcinoma↗
PubMed1989

[Hyperthermia--a new element in cancer treatment].

The efficacy of radiation therapy combined with local hyperthermia is demonstrated by three case studies. Mode of action and problems are discussed and published results reported. Human tumour cells obtained of biopsies from our patients before the onset of treatments were investigated. The short time cell cultures were treated either with hyperthermia or irradiation alone or with combinations under the same conditions as the clinical treatments. We could clearly demonstrate that cell cultures of human origin respond to irradiation or hyperthermia. But the effect was limited and only cultures treated with combined modalities did not relapse. There is hope that mega-voltage radiation complemented with hyperthermia have a similar effect as high-LET-radiation. Side effects have been moderate so far using an extended clinical use.

Adenocarcinoma↗