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Featured researches published by Johannes Classen.


Journal of Clinical Oncology | 2003

Radiotherapy for Stages IIA/B Testicular Seminoma: Final Report of a Prospective Multicenter Clinical Trial

Johannes Classen; Heinz Schmidberger; Christoph Meisner; Rainer Souchon; Marie-Luise Sautter-Bihl; Rolf Sauer; Stefan Weinknecht; Kai-U. Köhrmann; Michael Bamberg

PURPOSE A prospective multicenter trial was initiated to evaluate the role of modern radiotherapy with reduced treatment portals for stage IIA and IIB testicular seminoma. PATIENTS AND METHODS Patients with stages IIA/B disease (Royal Marsden classification) were assessable for the trial. Staging comprised computed tomography of the chest, abdomen, and pelvis as well as analysis of tumor markers alpha-fetoprotein and beta human chorionic gonadotropin. Linac-based radiotherapy was delivered to para-aortic and high ipsilateral iliac lymph nodes. The total doses were 30 Gy for stage IIA and 36 Gy for stage IIB disease. RESULTS Between April 1991 and March 1994, 94 patients were enrolled for the trial by 30 participating centers throughout Germany. Seven patients were lost to follow-up. Median time to follow-up of 87 assessable patients was 70 months. There were 66 stage IIA and 21 stage IIB patients. One mediastinal and one field-edge relapse were observed in the stage IIA group. In the stage IIB group, there was one mediastinal and one mediastinal/pulmonary relapse. All patients were treated with a salvage regimen of platinum-based chemotherapy. Actuarial relapse-free survival at 6 years was 95.3% (95% confidence interval [CI], 88.9% to 100%) and 88.9% (95% CI, 74.4% to 100%) for stage IIA and IIB groups, respectively. Maximum acute side effects were 8% grade 3 nausea for stage IIA and 10% grade 3 nausea and diarrhea for stage IIB groups. No late toxicity was observed. CONCLUSION Radiotherapy for stages IIA/B seminoma with reduced portals yields excellent tumor control at a low rate of acute toxicity and no late toxicity, which supports the role of radiotherapy as the first treatment choice for these patients.


International Journal of Radiation Oncology Biology Physics | 2002

Radiotherapy alone in technically operable, medically inoperable, early-stage (I/II) non-small-cell lung cancer.

Branislav Jeremic; Johannes Classen; Michael Bamberg

PURPOSE To investigate the effectiveness of high-dose, curative radiotherapy (RT) given alone in technically operable, but medically inoperable, patients with early-stage (I-II) non-small-cell lung cancer (NSCLC). METHODS AND MATERIALS Computerized and manual searches were done to identify published reports dealing with curative RT for NSCLC. Relevant studies were identified and the information provided therein was extracted regarding patient and treatment characteristics, treatment outcome, and various pretreatment and treatment-related factors influencing outcome, as well as toxicity and quality-of-life issues. RESULTS Although a large variation of pretreatment and treatment characteristics was noted in the available studies, a median survival time of >30 months and a 5-year survival rate of up to 30% had been achieved. Accumulated experience seems to suggest that doses of at least 65 Gy with standard fractionation, or its equivalent when altered fractionation is used, are necessary for control of NSCLC. Smaller tumors seem to have a favorable prognosis, and the issue of elective nodal RT continues to be controversial. Analyses of patterns of failure have clearly identified local failure as the predominant pattern. Although a number of potential pretreatment patient- and tumor-related prognostic factors have been examined, none has been shown to clearly influence survival. Toxicity was usually low, but very high doses (e.g., 80 Gy) given with a conventional approach may carry a risk of an excessive rate of side effects. CONCLUSION High-dose, curative RT is an effective treatment modality in technically operable, but medically inoperable, patients with early-stage NSCLC.


British Journal of Cancer | 2004

Para-aortic irradiation for stage I testicular seminoma: results of a prospective study in 675 patients. A trial of the German testicular cancer study group (GTCSG).

Johannes Classen; Heinz Schmidberger; C Meisner; C Winkler; J Dunst; R Souchon; L Weissbach; V Budach; W Alberti; Michael Bamberg

A prospective nonrandomised trial was performed in order to evaluate tumour control and toxicity of low-dose adjuvant radiotherapy in stage I seminoma with treatment portals confined to the para-aortic lymph nodes. Between April 1991 and March 1994, 721 patients were enrolled for the trial by 48 centres in Germany. Patients with pure seminoma and no evidence of lymph node involvement or distant metastases received 26 Gy prophylactic limited para-aortic radiotherapy. Disease-free survival at 5 years was the primary end point. With a median follow-up of 61 months, 675 patients with follow-up investigations were evaluable for this analysis. Kaplan–Meier estimates of disease-free and disease-specific survival were 95.8% (95% CI: 94.2–97.4) and 99.6% (95% CI: 99.2–100%) at 5 years and 94.9% (95% CI: 92.5–97.4%) and 99.6% (95% CI: 99.2–100%) at 8 years, respectively. A total of 26 patients relapsed. All except two were salvaged from relapse. In all, 21 recurrences were located in infradiaphragmatic lymph nodes without any ‘in-field’ relapse. Nausea and diarrhoea grade 3 were observed in 4.0 and 1.0% of the patients, respectively. Grade 3 late effects have not been observed so far. The results of our trial lend further support to the concept of limited para-aortic irradiation as the recently defined new standard of radiotherapy in stage I seminoma. There is no obvious compromise in disease-specific or disease-free survival compared to more extensive hockey-stick portals, which were used as standard portals at the time this study was initiated.


British Journal of Cancer | 2003

Radiotherapy with 16 Gy may fail to eradicate testicular intraepithelial neoplasia: preliminary communication of a dose-reduction trial of the German Testicular Cancer Study Group

Johannes Classen; K Dieckmann; Michael Bamberg; R Souchon; S Kliesch; M Kuehn; V Loy

Low-dose radiotherapy to the testis is effective in eradicating testicular intraepithelial neoplasia (TIN, carcinoma in situ of the testis) at the risk of androgenic deficiency. The present trial was designed to define the lowest dose effective to control TIN assuming a dose–response relation of radiation-induced endocrinological damage. Patients with TIN in a solitary testicle or with bilateral TIN were treated with 18 Gy (14 patients) and 16 Gy (26 patients) (5 × 2 Gy per week). Biopsies to ascertain clearance of TIN were performed after 6 and 24 months. The median time of follow-up is 20.5 months. There were three adverse events. In one patient, relapse of TIN along with microinvasive seminoma was observed 2 years after 16 Gy irradiation. In two other patients, persistent spermatogonia were observed with the 16 and 18 Gy regimen after 6 and 24 months, respectively. All other post-treatment biopsies showed the Sertoli cell-only pattern. These results confirm that TIN is a radiosensitive lesion efficiently controlled in most cases with doses below 20 Gy. However, sporadic failures may occur. A dose of 16 Gy is probably unsafe and should no longer be used. Future investigations should not only focus on total dosage of irradiation but also on fractionation schedules.


International Journal of Radiation Oncology Biology Physics | 1997

Radiotherapy in stage IIA and IIB testicular seminoma with reduced portals: A prospective multicenter study

Heinz Schmidberger; Michael Bamberg; Christof Meisner; Johannes Classen; Cornelia Winkler; Michael Hartmann; Rainer Templin; Thomas Wiegel; Wolfgang Dornoff; Dieter Ross; Hans-Joachim Thiel; Carmen Martini; Wulf Haase

Purpose: A prospective multicenter study was carried out to estimate the treatment outcome of radiotherapy in Stage II seminoma after the application of modern staging and radiotherapy techniques. The lower margin of the iliac field was positioned on the upper rim of the acetabulum to reduce the amount of scattered irradiation to the remaining testicle. Methods and Materials: The study was carried out in 25 centers in Germany. Patients with pure seminoma, negative AFP-values, and retroperitoneal lymph node metastases of less than 5 cm in diameter were entered into the study. All patients received a ventrodorsal opposed field irradiation of the para-aortic and the ipsilateral iliac lymph nodes. The fields extended from the top of the 11th thoracic vertebra to the top of the acetabulum. Patients in Stage IIA (lymph nodes <2 cm ) received 30 Gy, and patients with Stage IIB (lymph nodes between 2 and 5 cm) 36 Gy total dose. Results: 39 patients in Stage IIA and 19 patients in Stage IIB were evaluated. After a median observation time of 37 months all patients are alive and disease free. Recurrence free survival in stage IIA was 100%. Two patients in Stage IIB experienced a recurrence 10 and 17 months after the end of radiotherapy. The actuarial recurrence free survival estimate in Stage IIB was 94.1% for 1 year and 87.4% for 2 years. One recurrence in Stage IIB occurred in the mediastinum, one in the mediastinum, and one the lung. Both patients could be salvaged by chemotherapy. There were no pelvic recurrences. The treatment was well tolerated, with nausea being the most common side effect (56.9% Grade 1, 15.5% Grade 2, and 8.6% Grade 3). Diarrhea occurred in 15.5% (Grade 1), 15.5% (Grade 2), and 5.2% (Grade 3) of the patients. Conclusions: The outcome of para-aortic and ipsilateral iliac irradiation in Stage IIA/B testicular seminoma is excellent with the currently available staging methods and treatment facilities. The treatment is well tolerated. The lower margin of the iliacal field can be placed at the acetabulum.


International Journal of Cancer | 1999

Radiotherapy for stages I and IIA/B testicular seminoma

Michael Bamberg; Heinz Schmidberger; Christoph Meisner; Johannes Classen; Rainer Souchon; Stefan Weinknecht; Johannes Schorcht; Frank Walter; R. Engenhart-Cabillic; Ulrich Schulz; Holger Born; Maria Flink

Radiotherapy is generally accepted as a standard treatment for early‐stage testicular seminoma. Relapse rates of 2% to 5% in clinical stage I and 10% to 20% in stage IIA/B (according to the Royal Marsden classification) can be achieved. Disease‐specific survival reaches 100%. With such excellent cure rates, treatment‐related side effects gain particular importance. Therefore, a prospective multicenter trial was initiated for radiotherapy of testicular seminoma with limited treatment portals and low total doses of irradiation. In clinical stage I, 483 patients were treated with 26 Gy to the para‐aortic region only. In stage IIA, 42 patients and, in stage IIB, 18 patients received irradiation to the para‐aortic and high iliac lymph nodes with 30 and 36 Gy, respectively. With a median time to follow‐up of 55 months for stage I and 55.5 months for stage IIA/B, there were 18 (3.7 %) and 4 (6.7 %) cases of relapse in both treatment groups. Disease‐specific survival was 99.6% in stage I and 100% in stage IIA/B. Acute toxicity was dominated by moderate gastro‐intestinal side effects. No major late toxicity has been observed to date. Limited volume pure para‐aortic treatment for stage I and para‐aortic/high iliac irradiation for stage IIA/B with 26, 30 and 36 Gy, respectively, yields excellent cure rates with only moderate acute toxicity and is therefore recommended as standard treatment. Int. J. Cancer 83:823–827, 1999.


Drugs | 2006

Advances in the Treatment of Testicular Cancer

Hans-Georg Kopp; M.A. Kuczyk; Johannes Classen; A. Stenzl; Lothar Kanz; Frank Mayer; Michael Bamberg; J. T. Hartmann

Testicular cancer is the most common solid tumour in young men, and the treatment of testicular germ cell tumours (TGCT) has been called a success story of medical oncology, germ cell cancer being regarded as the “model of a curable neoplasm”. Even with metastatic disease, high cure rates can be achieved: the overall 5-year survival for all stages of TGCT is approximately 80%. Today, elaborate systems for prognostic evaluation for gonadal and extragonadal germ cell tumours facilitate the choice of the most appropriate therapy for individual patients. In doing so, the ultimate goal of treatment is tumour-free survival for any patient with TGCT.This goal has already been reached for >99% of the patients with early-stage tumours, as well as for the majority of patients with advanced disease (56% of patients with metastases are considered to have a good prognosis at the time of diagnosis; the 5-year survival rate for this group is 90%). However, patients with ‘intermediate’ or ‘poor’ prognosis at the time of diagnosis, as well as patients with relapsed disease after cisplatin-containing therapy, still have an unsatisfactorily low 5-year survival rate after standard therapy with PEB (cisplatin, etoposide, bleomycin) of only 80%, 45–55% and 20–25%, respectively.Therefore, our goals must be (i) to limit acute and chronic toxicity by avoiding overtreatment for patients with localised disease and/or good prognosis with advanced disease; and (ii) to identify patients with poor prognosis and treat them in specialised centres, where not only is optimal interdisciplinary care available but new treatment strategies are being applied. For example, tandem high-dosechemotherapy regimens might be effective in achieving higher cure rates in these patients.


Journal of Cancer Research and Clinical Oncology | 1999

Chemotherapy in the treatment of recurrent glioblastoma multiforme: ifosfamide versus temozolomide

Frank Paulsen; Wolfgang Hoffmann; Gerd Becker; C. Belka; Martin Weinmann; Johannes Classen; Rolf-Dieter Kortmann; Michael Bamberg

Purpose: Despite the progress made in neurosurgery and radiotherapy, the prognosis of glioblastoma multiforme (GB) is poor, due to the lack of an effective salvage therapy. In vitro analysis revealed activity for ifosfamide and temozolomide. The usefulness of these agents in recurrent disease was investigated. Methods: Six adult patients with recurrent GB received one to four courses of 1,500 mg/m2 ifosfamide given over 5 days intravenously. Furthermore, temozolomide (100–200 mg/m2) was given orally over 5 days to 14 patients. Results: After ifosfamide treatment, one partial response and two cases of stable disease were observed. The median survival time was 24 weeks (range of 9–52 weeks). Toxicity analysis revealed one paranoid reaction, three grade III leukocytopenia, and one grade I–II nausea, anemia, and hematuria. Temozolomide therapy resulted in three partial responses and four cases of stable disease. The median survival time (Kaplan-Meier) was 21 weeks (range 4–64 weeks). The major toxicities were grade I–II nausea and hematological side effects (one case of grade IV leuko- and thrombocytopenia). Conclusions: Ifosfamide treatment might be a feasible approach, but it necessitates hospitalization. Temozolomide showed promising results. Due to its oral application, the patients quality of life (time out of hospital) is favorable. Subgroups with improved survival were observed.


British Journal of Cancer | 2002

Mitomycin C in combination with radiotherapy as a potent inhibitor of tumour cell repopulation in a human squamous cell carcinoma.

W. Budach; Frank Paulsen; Stefan Welz; Johannes Classen; H. Scheithauer; P Marini; C. Belka; Michael Bamberg

The potential of Mitomycin C in combination with fractionated irradiation to inhibit tumour cell repopulation of a fast growing squamous cell carcinoma after fractionated radiotherapy was investigated in vivo. A rapidly growing human squamous cell carcinoma (FaDudd) was used for the study. For experiments, NMRI (nu/nu) mice with subcutaneously growing tumours were randomly allocated to no treatment, Mitomycin C, fractionated irradiation (ambient: 11x4.5 Gy in 15 days), or fractionated irradiation combined with Mitomycin C. Graded top up doses (clamped blood flow: 0–57 Gy) were given at day 16, 23, 30 or 37. End point of the study was the time to local tumour progression. Data were examined by multiple regression analysis (Cox). Mitomycin C alone resulted in a median time to local tumour progression of 23 (95% confidence limits: 17–43) days, fractionated irradiation in 31 (25–35) days and combined Mitomycin C plus fractionated irradiation in 65 (58–73) days (P=0.02). Mitomycin C decreased the relative risk of local recurrence by 94% (P<<0.001) equivalent to 31.7 Gy top up dose. Repopulation accounted for 1.33 (0.95–1.72) Gy per day top up dose after fractionated irradiation alone and for 0.68 (0.13–1.22) Gy per day after fractionated irradiation+Mitomycin C (P=0.018). Mitomycin C significantly reduces the risk of local recurrence and inhibits tumour cell repopulation in combination with fractionated irradiation in vivo in the tested tumour model.


Journal of Cancer Research and Clinical Oncology | 2001

Treatment of early stage testicular seminoma

Johannes Classen; Rainer Souchon; Thomas Hehr; Michael Bamberg

Abstract Stage I and IIA/B testicular seminoma represent approximately 45% of all testicular germ cell tumours. Due to the availability of highly efficient salvage treatment, the disease-specific survival in stage I seminoma is approximately 100%, irrespective of the choice of adjuvant treatment. Radiotherapy with 26 Gy to the paraaortic/paracaval lymph nodes yields excellent cure rates of 95–98% with a favourable profile of acute and late toxicity. Likewise, phase-II trials with single-agent carboplatinum systemic treatment have demonstrated a rate of relapse of 3–4% on average. However, carboplatinum chemotherapy has to be regarded as experimental until data of phase-III trials are available. Surveillance in stage I disease is conflicted with a rate of relapse of approximately 20%. However, 80% of the patients will avoid potentially toxic overtreatment by the watch-and-wait policy. In stage IIA/B seminoma, “dogleg” radiotherapy with 30 Gy and 36 Gy, respectively, provides high cure rates of 90–95%. Those patients relapsing will be salvaged in almost 100% of cases. Testicular intraepithelial neoplasia (TIN) is the common precursor lesion of testicular germ cell tumours except for spermatocytic seminoma. In case of TIN in a single testis or bilateral TIN, local radiotherapy with 18 Gy is recommended as standard treatment.

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Thomas Hehr

University of Tübingen

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Wilfried Budach

University of Düsseldorf

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W. Budach

University of Tübingen

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Volker Loy

Free University of Berlin

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