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Volker Diehl

Publications and source records attributed to Volker Diehl.

At least 19 recordsLinked to original sources
PubMed2006

Rituximab added to an intensified salvage chemotherapy program followed by autologous stem cell transplantation improved the outcome in relapsed and refractory aggressive non-Hodgkin lymphoma.

We investigated the addition of rituximab to an intensified salvage program followed by a myeloablative course with autologous stem cell transplantation (ASCT) in patients with relapsed or refractory aggressive non-Hodgkin lymphoma (NHL). Patients with relapsed or progressive aggressive NHL were treated with two cycles of conventional salvage chemotherapy (DHAP) followed by high-dose sequential chemotherapy (cyclophosphamide, methotrexate with vincristine and etoposide) and a final myeloablative course (BEAM) with ASCT. Rituximab (375 mg/m(2)) was administered at each treatment cycle. This cohort was compared with a historical control group of patients treated with the same chemotherapy but without rituximab. Patients from both groups were matched by duration of first remission and lactate dehydrogenase serum levels. Forty-five patients were treated with chemotherapy and 22 with immunochemotherapy. The overall response rates (ORR) at the final evaluation were 63% for the immunochemotherapy group and 42% for the chemotherapy group (p = 0.330). In the historical controlled analysis freedom from second failure (FF2F) at 2 years in the immunochemotherapy group was 57% and overall survival (OS) was 77%. FF2F in the chemotherapy group was 18% (p = 0.0051) and OS was 37% (p = 0.0051). In the matched-pair analysis, FF2F was 58% in the immunochemotherapy group compared to 16% in the chemotherapy group (p = 0.0517); OS was 74 vs 33%, respectively (p = 0.0424). The toxicity was tolerable and comparable in both groups. The addition of rituximab to an intensified salvage chemotherapy regimen seems to improve the prognosis. However, only prospective randomized trial can offer sufficient data of the value of rituximab in relapsed and refractory aggressive NHL.

Adult↗
PubMed2006

Sensitivity analysis of cost factors for various therapy options in the treatment of follicular lymphoma.

BACKGROUND: In Germany, patients with relapsed follicular non-Hodgkin's lymphoma do not all receive the same treatment. In this study, 3 therapy regimens were analyzed which were considered to be similar. With the goal of determining the treatment option with the lowest direct costs whilst maintaining the same degree of effectiveness, a cost analysis model was established and applied by way of example to the existing illness constellation. METHODS: The German doctors' fee scale (Einheitlicher Bewertungsmassstab, EBM) valid until 2005 served as the basis for the calculation of medical services within the scope of the present statutory health insurance guidelines. A virtual standard patient was constructed for the cost model and treated with the different therapy regimens. The incidences of individual adverse events described in literature served as the basis for the characterization of the average toxicity of the respective treatment methods. RESULT: The overall costs result from the sum of the treatment costs and the toxicity-related costs. The effect of additional interventions on the overall cost was also examined. CONCLUSION: Whereas the accompanying documentation of costs in clinical studies is organizationally complex and very tedious, the model applied here offers a reliable method of quantifying the costs of the different therapy regimens. It permits the comparison of different treatment alternatives, and it enables, by means of a cost variance analysis, the identification of cost drivers and less expensive measures within a therapy method.

Antibodies, Monoclonal↗
PubMed2006

Immunophenotyping of surface antigens in acute myeloid leukemia by flow cytometry after red blood cell lysis.

Immunophenotyping of acute leukemia using flow cytometry after density gradient separation (dg-sep) of mononuclear cells is the international gold standard. But destroying red cells by whole blood lysis (wb-lysis) after direct staining has found a broad usage. Both methods revealed congruent results in phenotyping of 26 cases of acute myeloid leukemias by testing CD4, CD7, CD11b, CD11c, CD13, CD14, CD15, CD33, CD34, CD65s, Glycophorin A and HLA-DR antigens. Mean values of these tested antigens were very similar. Only low antigen expression of CD2 was missed in the phenotype of two AML cases by the wb-lysis (23 and 29% positive cells by the dg-sep).

Adult↗
PubMed2006

Current strategies and new approaches in the treatment of Hodgkin's lymphoma.

As a result of continuous improvement in therapeutic options and their verification by large multicenter trials, Hodgkin's lymphoma (HL) has become one of the best curable cancers in adults. Nowadays, about 80-90% of patients in all stages achieve long-term survival. Nevertheless, these good results are threatened by treatment-associated toxicities such as infertility, cardiopulmonary toxicity and secondary malignancies. It is therefore the aim of future trial generations both to maintain excellent treatment results and to minimize late effects. At early stages, ongoing trials ask how many cycles of ABVD-like chemotherapy are necessary and if radiation doses might be further reduced or even omitted in favorable early-stage disease. In advanced stages, new combinations of chemotherapeutic drugs with higher dose densities are tested with or without the application of consolidating radiotherapy. The treatment of patients with relapsed HL depends on previous therapies with radiotherapy, chemotherapy or high-dose chemotherapy followed by autologous stem cell transplantation. For patients with multiple relapses, experimental treatment strategies include antibody- and small-molecule-based regimens. In this review we present current treatment strategies for patients with a first diagnosis of HL and relapsed HL as well as recent experimental therapeutic approaches.

Chemotherapy, Adjuvant↗
PubMed2006

German Hodgkin's Lymphoma Study Group trials: lessons from the past and current strategies.

Over the past decades, Hodgkin's lymphoma has become one of the most curable tumors in adults. This is mainly because of large clinical trials using risk-adapted, highly effective therapy modalities. For a long time, radiation therapy was the standard for treating patients with Hodgkin's lymphoma. Within the past 20 years, management has undergone a paradigm shift from the use of chemotherapy as an adjunct to radiation therapy in advanced-stage disease to combined therapy modalities with chemotherapy and involved-field irradiation in early stages and time- and dose-intensified effective drug regimens in advanced stages. Modern therapeutic strategies aim at reducing therapy-associated acute and late toxicities, while maintaining the highest tumor control. Founded in 1978, the German Hodgkin's Lymphoma Study Group has initiated numerous clinical trials contributing to the high cure rate in all stages of this lymphoma entity. This article gives an overview of the German Hodgkin's Lymphoma Study Group trials and a review of the current treatment strategies.

Antineoplastic Agents↗
PubMed2006

Pegfilgrastim support for full delivery of BEACOPP-14 chemotherapy for patients with high-risk Hodgkin's lymphoma: results of a phase II study.

The primary endpoint of this feasibility study was to determine whether pegfilgrastim support could enable the delivery of the full dose of BEACOPP chemotherapy every 14 days on schedule. Forty-one patients with high-risk Hodgkin's lymphoma were randomized to receive pegfilgrastim (6 mg) on day 4 or 8 of each cycle. Eighty-one percent of cycles administered were delivered at full dose and on schedule (FDOS). Response was retrospectively assessed in 27 patients at 6 months; 23 of these 27 patients (85%) achieved a complete response and one (4%) achieved a partial response. Toxicities were mostly moderate in intensity. These results support the feasibility of delivering full dose, on schedule BEACOPP-14, chemotherapy with pegfilgrastim support.

Adolescent↗
PubMed2005

Secondary amenorrhea after Hodgkin's lymphoma is influenced by age at treatment, stage of disease, chemotherapy regimen, and the use of oral contraceptives during therapy: a report from the German Hodgkin's Lymphoma Study Group.

PURPOSE: Long-term survivors of successfully treated Hodgkin's lymphoma (HL) are at risk for late complications. Among these, infertility for female patients is of major importance. The subject of this analysis is to evaluate the menstrual status after HL therapy. PATIENTS AND METHODS: From 1994 to 1998, the German Hodgkin's Lymphoma Study Group conducted clinical trials for early-, intermediate-, and advanced-stage HL (trials HD7 to HD9) involving a total of 3,186 patients. A survey was carried out to evaluate the menstrual status after therapy. The following factors were assessed concerning their influence on amenorrhea: age, treatment, stage, and the use of oral contraceptives during chemotherapy. RESULTS: A total of 405 women aged younger than 40 years answered the study questions. After a median follow-up of 3.2 years, 51.4% of the women receiving eight cycles of dose-escalated bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (BEACOPP) had continuous amenorrhea. Amenorrhea was significantly more frequent after dose-escalated BEACOPP compared with doxorubicin, bleomycin, vinblastine, and dacarbazine; cyclophosphamide, vincristine, procarbazine, prednisone, doxorubicin, bleomycin, vinblastine, and dacarbazine; or standard BEACOPP (P = .0066). Amenorrhea after therapy was most pronounced in women with advanced-stage HL (P < .0001), in women older than 30 years at treatment (P = .0065), and in women who did not take oral contraceptives during chemotherapy (P = .0002). CONCLUSION: Most women who are treated for advanced-stage HL experience amenorrhea after therapy. Amenorrhea is significantly more frequent in women with advanced-stage HL receiving eight cycles of dose-escalated BEACOPP and in women older than 30 years at first treatment. Furthermore, the data show a statistical association between the use of oral contraceptives and return of menstrual cycle, which is subject to further investigation.

Adolescent↗
PubMed2005

Role of hematotoxicity and sex in patients with Hodgkin's lymphoma: an analysis from the German Hodgkin Study Group.

PURPOSE: Several scores have described sex as a prognostic factor in patients with Hodgkin's lymphoma (HL). However, little is known how sex-specific factors influence treatment outcome. We systematically investigated sex differences with regard to pretreatment characteristics and therapy-related variables, and examined their influence on the outcome of HL patients. PATIENTS AND METHODS: This analysis comprises 4,626 HL patients of all prognostic risk groups who were enrolled onto the multicenter studies HD4 to HD9 of the German Hodgkin Study Group. At 5.5 years, 2,050 female and 2,576 male patients were analyzed. RESULTS: Male and female patients had similar prognostic factors. There was more acute chemotherapy-related hematotoxicity in women, especially more severe leucopenia (WHO grade 3/4, 69.9% female and 55.2% male; P < .0001). Importantly, this did not translate into more infections. Female patients had similar response rates but fewer relapses and deaths, leading to a significantly better freedom from treatment failure (FFTF; at 66 months, 81% female [95% CI, 79% to 82%] and 74% male [95% CI, 72% to 76%]). Severe leucopenia during chemotherapy was strongly associated with better FFTF, both for males and females. In addition, when only those patients who developed severe leucopenia within the first two cycles of chemotherapy were included, the factor maintained its protective role. CONCLUSION: The protective role of severe leucopenia suggests the testing of a more individualized therapy. In future trials, this therapy may be tailored in a response-adapted manner depending on the individual toxicity profile within the first cycles.

Adolescent↗
PubMed2005

Molecular pathogenesis of Hodgkin's lymphoma.

According to the WHO classification, Hodgkin's lymphoma (HL) is subdivided into a classical variant and a nodular lymphocyte predominant variant which are characterized by the presence of Hodgkin's and Reed-Sternberg (H-RS) cells or lymphocytic and histiocytic (L&H) cells, respectively. This article reviews genetic characteristics and transcriptional changes of H-RS and L&H cells, including recent knowledge about transforming mechanisms and signaling pathways that contribute to the antiapoptotic phenotype displayed by H-RS and L&H cells. We also discuss major cellular and molecular mediators contributing to the establishment and maintenance of a reactive background in HL-affected tissues. We believe that an in-depth understanding of the pathogenesis of HL will eventually lead to the development of novel biologically based therapeutic strategies in the near future.

Female↗
PubMed2005

Phase I/II combined chemoimmunotherapy with carcinoembryonic antigen-derived HLA-A2-restricted CAP-1 peptide and irinotecan, 5-fluorouracil, and leucovorin in patients with primary metastatic colorectal cancer.

PURPOSE: We conducted a phase I/II randomized trial to evaluate the clinical and immunologic effect of chemotherapy combined with vaccination in primary metastatic colorectal cancer patients with a carcinoembryonic antigen-derived peptide in the setting of adjuvants granulocyte macrophage colony-stimulating factor, CpG-containing DNA molecules (dSLIM), and dendritic cells. EXPERIMENTAL DESIGN: HLA-A2-positive patients with confirmed newly diagnosed metastatic colorectal cancer and elevated serum carcinoembryonic antigen (CEA) were randomized to receive three cycles of standard chemotherapy (irinotecan/high-dose 5-fluorouracil/leucovorin) and vaccinations with CEA-derived CAP-1 peptide admixed with different adjuvants [CAP-1/granulocyte macrophage colony-stimulating factor/interleukin-2 (IL-2), CAP-1/dSLIM/IL-2, and CAP-1/IL-2]. After completion of chemotherapy, patients received weekly vaccinations until progression of disease. Immune assessment was done at baseline and after three cycles of combined chemoimmunotherapy. HLA-A2 tetramers complexed with the peptides CAP-1, human T-cell lymphotrophic virus type I TAX, cytomegalovirus (CMV) pp65, and EBV BMLF-1 were used for phenotypic immune assessment. IFN-gamma intracellular cytokine assays were done to evaluate CTL reactivity. RESULTS: Seventeen metastatic patients were recruited, of whom 12 completed three cycles. Therapy resulted in five complete response, one partial response, five stable disease, and six progressive disease. Six grade 1 local skin reactions and one mild systemic reaction to vaccination treatment were observed. Overall survival after a median observation time of 29 months was 17 months with a survival rate of 35% (6 of 17) at that time. Eight patients (47%) showed elevation of CAP-1-specific CTLs. Neither of the adjuvants provided superiority in eliciting CAP-1-specific immune responses. During three cycles of chemotherapy, EBV/CMV recall antigen-specific CD8+ cells decreased by an average 14%. CONCLUSIONS: The presented chemoimmunotherapy is a feasible and safe combination therapy with clinical and immunologic efficacy. Despite concurrent chemotherapy, increases in CAP-1-specific T cells were observed in 47% of patients after vaccination.

Adult↗
PubMed2005

Patterned CpG methylation of silenced B cell gene promoters in classical Hodgkin lymphoma-derived and primary effusion lymphoma cell lines.

Hodgkin and Reed-Sternberg (HRS) cells of classical Hodgkin lymphoma (cHL) and primary effusion lymphoma (PEL) are derived from germinal center (GC) and post-GC B cells, respectively. Neither express many of the B cell genes or surface markers typically expressed by other GC-derived B cell lymphomas or normal B cells. This loss of B cell gene expression is not due to a lack of essential transcription factors, as studies have shown that the ectopic expression of missing transcription factors failed to reactivate endogenous target genes. These results implicate epigenetic mechanisms extinguishing B cell gene expression. Silenced endogenous B cell genes representing a surface receptor, B29 (Igbeta, CD79b), a signaling molecule, TCL1, and a transcription factor, Bob1 (OCA-B, OBF-1), were reactivated by 5-aza-2'-deoxycytidine, indicating that gene silencing in HRS and PEL cells is due to DNA methylation. Genomic bisulfite sequencing corroborated this prediction and revealed three distinct patterns of methylation for the silenced B29 and TCL1 promoters. These distinct patterns consisted of 5' promoter CpG methylation alone, 5' and 3' promoter CpG methylation sparing sites in the central cores, and complete CpG methylation throughout the promoter regions. The silenced Bob1 promoter showed one pattern of dense CpG methylation at essentially all sites. These consistent patterns predict that, although gene silencing in many HRS and PEL cells mimics appropriate gene silencing, in some cases of complete CpG methylation throughout entire promoters both the activation and targeting of methylation is abnormal.

B-Lymphocytes↗
PubMed2005

Treatment of refractory Hodgkin's lymphoma patients with an iodine-131-labeled murine anti-CD30 monoclonal antibody.

PURPOSE: Hodgkin's lymphoma (HL) has been demonstrated to be a good target for immunotherapy since lymphocyte activation markers such as CD30 are expressed in high numbers on the malignant cells. Thus, we developed a new radioimmunoconjugate consisting of the murine anti-CD30 monoclonal antibody (MAb) Ki-4 labeled with iodine-131 ((131)I). PATIENTS AND METHODS: The biodistribution of (131)I-Ki-4 was assessed via dosimetry after preinfusion of 5 mg native Ki-4 followed by 250 to 300 MBq (131)I-labeled Ki-4. Whole-body scintigraphy was performed 1 hour, 24 hours, 48 hours, 72 hours, and 6 days after the infusion. Dosimetry was calculated using the programs NucliDose ICON-IDL (version 5.0.2; Siemens, Erlanger, Germany) and MIRDOSE (version 3.1; Oak Ridge National Laboratories; Oak Ridge, TN). The therapeutic dose was given on day 8 after preinfusion of unlabeled Ki-4. RESULTS: We treated 22 patients with relapsed or refractory CD30-positive HL. Preinfusion of 5 mg native Ki-4 was sufficient to bind the soluble CD30. Imaging demonstrated localization of involved areas measuring 5 cm in diameter or more in four patients and 2.5 cm in one patient. Patients received total body doses of 0.035 Gy to 0.99 Gy. Acute toxicity was mild with grade 1 fatigue in 19 of 22 assessable patients. Seven patients experienced grade 4 degrees hematotoxicity 4 to 8 weeks after treatment. Response included one complete remission, five partial remissions, and three minor responses. CONCLUSION: Treatment with (131)I-Ki-4 is effective but can be associated with severe hematotoxicity.

Adolescent↗
PubMed2005

Lymphocyte-rich classical Hodgkin's lymphoma: clinical presentation and treatment outcome in 100 patients treated within German Hodgkin's Study Group trials.

PURPOSE: To investigate the clinical characteristics and treatment outcome of patients with lymphocyte-rich classical Hodgkin's lymphoma (LRCHL) compared with other histologic subtypes of Hodgkin's lymphoma (HL). PATIENTS AND METHODS: From a total of 2,715 patients with biopsy-proven HL treated within the trials HD7 to HD12 of the German Hodgkin's Study Group, 100 patients (4%) with LRCHL, 145 patients (5%) with lymphocyte-predominant HL (LPHL), 1,688 patients (62%) with nodular sclerosis, 731 patients (27%) with mixed cellularity, and 23 patients (1%) with lymphocyte depletion were identified. Patients with LRCHL had a median age of 38 years (range, 16 to 74 years). RESULTS: Compared with other histologic subtypes, patients with LRCHL are, on average, older and usually present with early stages of disease (stage I, 34%; stage II, 46%). The median time of follow-up was 32.2 months (95% CI, 28.2 to 37.0 months). Complete and partial remission was achieved in 96 patients (96%) and four patients (4%), respectively, with LRCHL. The event-free and overall survival rates were 97% (95% CI, 93% [corrected] to 100% [corrected]) and 97% (95% CI, 93% [corrected] to 100% [corrected]), respectively, at 30 months. Only three patients died; all of the deaths were caused by treatment-related toxicities. CONCLUSION: LRCHL is a distinct subtype of CHL, with features of CHL and LPHL, and is a rare entity accounting for only 4% of HLs. LRCHL has a different pattern of clinical presentation and age and sex distribution than other CHLs. It is associated with an excellent prognosis if treated with current treatment regimens. When treating patients with LRCHL, great attention should be paid to avoid acute toxicities.

Adolescent↗
PubMed2005

Elevated serum levels of CC thymus and activation-related chemokine (TARC) in primary Hodgkin's disease: potential for a prognostic factor.

The CC thymus and activation-related chemokine (TARC) is a protein, which is highly expressed by Reed-Sternberg cells in Hodgkin's disease and is found in the majority of Hodgkin's disease patients. Within several trials conducted by the German Hodgkin study group, 62 Hodgkin's disease patients were elected based on availability of serum samples post and prior therapy to assess TARC levels by ELISA. TARC levels from 33 patients with continuous complete response (CCR), 20 patients with relapse, and nine patients with progressive disease (PD) were correlated with freedom from treatment failure and survival. As defined in healthy donors (mean value +/- 2x SD), a TARC level of >500 pg/mL was considered as elevated. The median TARC levels of all patients at baseline and after completed primary treatment were 5,803 pg/mL (range, 116-73,074 pg/mL) and 663 pg/mL (50-24,709 pg/mL), respectively. TARC levels of patients with PD were higher than those of patients with CCR at baseline and after therapy. Baseline TARC correlated significantly with stage (P = 0.019), erythrocyte sedimentation rate (P = 0.004), leukocyte count (P < 0.001), and lymphocyte count (P = 0.026). A TARC level of >2,000 pg/mL after completed treatment was a significant risk factor for poorer survival (P = 0.02) but not for relapse. In conclusion, monitoring serum TARC levels in Hodgkin's disease patients may add valuable information about therapy success in Hodgkin's disease patients, especially those with PD and should therefore be prospectively evaluated in future trials.

Adolescent↗
PubMed2005

Hodgkin's lymphoma in elderly patients: a comprehensive retrospective analysis from the German Hodgkin's Study Group.

PURPOSE: With improved prognosis for patients with Hodgkin's lymphoma (HL), interest increasingly focuses on high-risk groups such as elderly patients. We thus performed a retrospective analysis using the German Hodgkin's Study Group (GHSG) database to determine clinical risk factors, course of treatment, and outcome in elderly HL patients in comparison with younger adults. PATIENTS AND METHODS: A total of 4,251 patients included in the GHSG studies HD5 to HD9 were analyzed, of whom 372 (8.8%) were 60 years or older and 3,879 (91.2%) were younger than 60 years. Patient characteristics, treatment results, toxicity, freedom from treatment failure (FFTF), and overall survival (OS) were compared. RESULTS: Elderly patients more often had mixed cellularity subtype, "B" symptoms, elevated erythrocyte sedimentation rate, and poorer performance status. Less frequently observed were nodular sclerosis subtype, large mediastinal mass, and bulky disease. Acute toxicity during chemotherapy was generally higher in elderly patients. This was most obvious for severe infections (grade 3 or 4; 15% v 6%) correlating with more severe leukopenia in elderly patients (grade 4; 38% v 23%). As a result, significantly fewer elderly patients received the intended full chemotherapy dose (75% v 91%). The survival analysis showed a significantly poorer treatment outcome for elderly patients in terms of 5-year OS (65% v 90%), FFTF (60% v 80%), and HL-specific FFTF (73% v 82%). CONCLUSION: Elderly patients have a poorer risk profile compared with younger HL patients and experience more severe treatment-associated toxicity. Higher mortality during treatment as well as lower dose-intensity are the major factors explaining the poorer overall outcome of elderly HL patients.

Age Factors↗
PubMed2005

Biophysical analysis of the acute toxicity of radiotherapy in Hodgkin's lymphoma--a comparison between extended field and involved field radiotherapy based on the data of the German Hodgkin Study Group.

PURPOSE: To determine biophysical parameters from the complication probability data during and after radiotherapy of Hodgkin's lymphoma (HL), based on the number of gastrointestinal side effects that were found in the multicenter HD8 trial of the German Hodgkin Lymphoma Study Group. METHODS AND MATERIALS: Between 1993 and 1998, 1204 patients with newly diagnosed, histology-proven HL in clinical Stages I/IIA/IIB with defined risk factors and stage IIIA without risk factors were enrolled into the multicenter HD8 study. Patients were randomized to receive two cycles of COPP (cyclophosphamide, vincristine, procarbazine, prednisone) alternating with two cycles of ABVD (doxorubicin, bleomycin, vinblastine, dacarbazine) followed by radiotherapy (RT) of 30 Gy extended field plus 10 Gy to bulky disease (Arm A) or 30 Gy involved field plus 10 Gy to bulky disease (Arm B). For 910 patients, the rates of acute gastrointestinal side effects during and after RT could be determined. Comparison showed differences between Arms A and B (Grade 1-2: 16.6 vs. 3.9; Grade 3-4: 0.9 vs. 0.2; p < 0.001). From the dose-volume histograms for a "standard patient" (volume intestine 2300 cm3), we determined the normal tissue complication probability (NTCP) (V, D, m, n, TD50), the biophysical parameter TD50, and n (volume dependent) in such a manner that the observed NTCP in Arm A in cases of supradiaphragmatic involvement only and in cases of infradiaphragmatic involvement correlated with the calculated values. RESULTS: Of 1,204 patients randomized, 1,064 patients were informative for the comparison of study arms. The median observation time was 54 months. The overall survival for all eligible patients was 91%, and freedom from treatment failure was 83%. Survival rates at 5 years after start of RT revealed no differences in terms of freedom from treatment failure (85.8% in Arm A, 84.2% in Arm B) and overall survival (90.8% and 92.4%). There were also no differences between the two arms in terms of complete remission, progressive disease, relapse, death, and secondary neoplasias. In contrast, acute side effects, including leukopenia, thrombocytopenia, nausea, gastrointestinal toxicity, and pharyngeal toxicity, were more frequent in the extended field arm. Concerning gastrointestinal toxicity, the different radiation treatment volumes resulted in different NTCPs. On the basis of these findings, values of n = 0.09 and TD50 = 32 Gy were derived. However, this biophysical model is sensitive to variations of the parameters. A deviation of 1% of TD50 results in a deviation of 10% of the NTCP. CONCLUSION: Radiotherapy volume reduction from extended field to involved field after two cycles of COPP/ABVD chemotherapy gives similar results and less toxicity in patients with early-stage, unfavorable HL. Biophysical parameters could be determined from the complication probability data after RT of HL. Because of the exponential dependence, this biophysical model is unstable. It represents a "start model" until further data can be incorporated.

Antineoplastic Combined Chemotherapy Protocols↗