Uwe Haverkamp

Total Skin Electron Beam for Primary Cutaneous T-cell Lymphoma.

PURPOSE Recent trials with low-dose total skin electron beam (TSEB) therapy demonstrated encouraging results for treating primary cutaneous T-cell lymphoma (PCTCL). In this study, we assessed the feasibility of different radiation doses and estimated survival rates of different pathologic entities and stages. METHODS AND MATERIALS We retrospectively identified 45 patients with PCTCL undergoing TSEB therapy between 2000 and 2015. Clinical characteristics, treatment outcomes, and toxicity were assessed. RESULTS A total of 49 courses of TSEB therapy were administered to the 45 patients. There were 26 pathologically confirmed cases of mycosis fungoides (MF) lymphoma, 10 cases of Sézary syndrome (SS), and 9 non-MF/SS PCTCL patients. In the MF patients, the overall response rate (ORR) was 92% (50% complete remission [CR]), 70% ORR in SS patients (50% CR), and 89% ORR in non-MF/SS patients (78% CR). The ORR for MF/SS patients treated with conventional dose (30-36 Gy) regimens was 92% (63% CR) and 75% (25% CR) for low-dose (<30-Gy) regimens (P=.09). In MF patients, the overall survival (OS) was 77 months with conventional dose regimens versus 14 months with low-dose regimens (P=.553). In SS patients, the median OS was 48 versus 16 months (P=.219), respectively. Median event-free survival (EFS) for MF in conventional dose patients versus low-dose patients was 15 versus 8 months, respectively (P=.264) and 19 versus 3 months for SS patients (P=.457). Low-dose regimens had shorter treatment time (P=.009) and lower grade 2 adverse events (P=.043). A second TSEB course was administered in 4 MF patients with 100% ORR. There is a possible prognostic impact of supplemental/boost radiation (P<.001); adjuvant treatment (P<.001) and radiation tolerability (P=.021) were detected. CONCLUSIONS TSEB therapy is an efficacious treatment modality in the treatment of several forms of cutaneous T-cell lymphoma. There is a nonsignificant trend to higher and longer clinical benefit for MF and SS patients receiving conventional dose. Low-dose TSEB regimens are well tolerated and achieve short-term palliation.

Radiotherapy Is Effective for Desmoid Tumors (Aggressive Fibromatosis) - Long-Term Results of a German Multicenter Study

Background: Desmoids (aggressive fibromatosis) are defined as benign neoplasms of the connective tissue that arise from the deep muscle fascia, aponeurosis, tendons, and scar tissue. Recurrence rates between 40 and 80% were reported after surgery alone. We addressed the impact of radiation therapy (RT) in the management of aggressive fibromatosis. Patients and Methods: A large literature review was performed, and the data was compared with the results of a multicenter study of the German Cooperative Group on Radiotherapy for Benign Diseases (GCG-BD). Results: This analysis included 52 patients treated with RT. 37 patients received postoperative RT (20 patients after R2 resection and 17 patients after R1 resection). 15 patients received RT alone (6 patients with inoperable primary tumor and 9 patients with inoperable recurrent tumor). In the case of postoperative RT, a median dose of 50 Gy (range 50-60 Gy) was used; for definitive RT, a median dose of 55 Gy (range 55-65 Gy) was used. The local control rate was 79% for the whole group. The median follow-up was 44 month (range 8-62 months). Conclusion: Given the large number of patients, these data show that RT is highly effective in the treatment of desmoid tumors. RT is an attractive alternative to mutilating surgery.

Radiotherapy in langerhans cell histiocytosis - a rare indication in a rare disease.

IntroductionLangerhans Cell Histiocytosis (LCH) represents a rare benign disorder, previously designated as “Histiocytosis X”, “Type II Histiocytosis” or “Langerhans Cell Granulomatosis”. Clinical presentation includes osteolysis, ulcerations of skin and soft tissues but also involvement of the CNS is described.Because treatment concepts are not well defined the German Cooperative Group on Radiotherapy for Benign Diseases performed a retrospective analysis.Methods and materialEight closely cooperating centres collected patients’ data of the past 45 years. As study endpoints disease free survival, recurrent disease, death and therapy related side effects were defined.ResultsA total of 80 patients with histologically proven LCH were irradiated within the past 45 years. According to the LCH classification of Greenberger et al. 37 patients had stage Ia, 21 patients stage Ib, 13 patients stage II and 9 patients stage IIIb and the median age was 29 years. The median Follow up was 54 months (range 9–134 months). A total of 39 patients had a surgical intervention and 23 patients a chemotherapy regimen.Radiation treatment was carried out with a median total dose of 15 Gy (range 3–50.4 Gy). The median single fraction was 2 Gy (range 1.8-3 Gy).Overall, 77% patients achieved a complete remission and 12.5% achieved a partial remission. The long-term control rate reached 80%. Within an actuarial overall 5-year survival of 90% no radiogenic side and late effects ≥EORTC/RTOG II° were observed.ConclusionIn the present study a large collective of irradiated patients was analysed. Radiotherapy (RT) is a very effective and safe treatment option and even low RT doses show sufficient local control.

Radiotherapy of splenomegaly : a palliative treatment option for a benign phenomenon in malignant diseases.

Purpose:Since the 20th century, radiotherapy (RT) has been used for treatment of symptomatic splenomegaly (SM). SM occurs in association with hematologic disorders. The purpose of this analysis was to determine the indication, treatment concepts, and efficiency of RT.Material and Methods: Clinical features, treatment concepts, and outcome data during the past 20 years were analyzed. Endpoints were pain relief, symptomatic and hematological response, and treatment-related side effects.Results:From 1989–2009, a total of 122 patients received 246 RT courses because of symptomatic SM. Overall 31 patients had chronic myelogenous leukemia (CML), 37 had chronic lymphocytic leukemia (CLL), 23 had osteomyelofibrosis (OMF), 17 had polycythemia vera (PV), 5 had acute myelogenous leukemia, 4 had idiopathic thrombocytopenic purpura (ITP), 3 had non-Hodgkin lymphoma (NHL), and 2 had multiple myeloma (MM). Patients were treated with 60Co gamma rays or 5–15MV photons. The fraction size ranged from 10–200 cGy and the total dose per treatment course from 30–1600 cGy. Significant pain relief was achieved for 74.8% of the RT courses given for splenic pain. At least 50% regression was attained for 77% of the RT courses given for SM. 36 patients died within 2 months due to the terminal nature of their disease. Of the RT courses applied for cytopenia, 73.6% achieved a significant improvement of hematological parameters and reduction of transfusion need. Notable hematologic toxicities were reported < EORTC/RTOG II°.Conclusion:The present analysis documents the efficacy of RT. In addition, RT as a palliative treatment option for symptomatic SM should not be forgotten.Einleitung:Seit Beginn des 20. Jahrhunderts hat die Radiotherapie (RT) ihren festen Stellenwert in der Behandlung einer symptomatischen Splenomegalie (SM). Die SM tritt bei hämatologischen Erkrankungen auf. Klinisch stehen Kapselschmerz sowie eine Zytopenie im Vordergrund. Die vorliegende Analyse untersucht Indikation, RT-Konzepte und die Effektivität der RT.Material und Methode:Patientendaten der letzten 20 Jahre wurden hinsichtlich klinischer Angaben, RT-Konzepte und Ergebnisse evaluiert. Endpunkte waren Schmerzfreiheit, hämatologisches Ansprechen nach RT sowie therapieassoziierte Nebenwirkungen.Ergebnisse:Zwischen 1989 und 2009 wurden 122 Patienten (79 Männer und 43 Frauen) mit insgesamt 246 RT-Serien behandelt. Folgende Grunderkrankungen waren Ursache für die Splenomegalie: CML (31), CLL (37), Osteomyelofibrose, (23), Polycyt haemia vera (17), AML (5), idiopathische Thrombozytopenie (4), Non-Hodgkin-Lymphom (3) und Plasmozytom (2) (Tabelle1). Die Behandlung erfolgte am Telekobalttherapiegerät oder am Linearbeschleuniger (5–15 MeV Photonen). Es wurden Einzelreferenzdosen zwischen 0,1–2 Gy und Gesamtreferenzdosen zwischen 3–16 Gy appliziert (Tabelle 2). Bei 74,8% der RT-Serien (74,8%), die aufgrund einer schmerzhaften Splenomegalie durchgeführt wurden, konnte eine Schmerzlinderung erzielt werden. Bei 77% der RT-Serien kam es zu einer Verkleinerung der Milz um bis zu 50% (Abbildung 1). 36 Patienten verstarben weniger als 2 Monaten nach Abschluss der RT im Rahmen der infausten Prognose ihrer Grunderkrankung. Bei 73,6% der RT-Serien kam es zu einer Verbesserung hinsichtlich Thrombozytopenien und die Transfusionsfrequenz nahm ab (Tabelle 3). Es wurden lediglich hämatologische Toxizitäten < II° (EORTC/RTOG) beobachtet.Schlussfolgerung:Die vorliegende Analyse belegt die hohe Effektivität der RT bei geringem Nebenwirkungsspektrum. Die RT der symptomatischen Splenomegalie sollte als wirksame palliative Option nicht in Vergessenheit geraten.

RESULTS OF FAST NEUTRON THERAPY OF ADENOID CYSTIC CARCINOMA OF THE SALIVARY GLANDS

BACKGROUND Adenoid cystic carcinomas (ACC) seem to have a better response to fast neutron irradiation than to photon beam therapy because of the higher relative biological effectiveness of neutron radiation. METHODS Between 1986 and 1995, 72 patients with ACC of the salivary glands were treated in Münster with fast neutrons. The median age was 54 years. All the patients had either recurrent or macroscopic rest tumor prior to neutron therapy. The median total dose was 15.03 Gy. Median follow-up was 50 months. RESULTS 39.1% of the patients achieved a complete remission and 48.6% a partial remission. The survival probability was 86% after one year, 73% after two years and 53% after five years. The recurrence-free survival was 83% after one year, 71% after two years and 45% after five years. CONCLUSION Neutron beam therapy seems to have been an effective treatment in these selected patients.IntroductionPatients with adenoid cystic carcinoma (ACC) of the salivary glands in the head and neck region have been reported to benefit from neutron radiotherapy according to significant clinical experience. A prospective clinical trial on the efficacy and treatment related morbidity of fast neutron radiotherapy was performed between 1986 and 1995 at the (d+T) 14 MeV neutron generator in Münster.Material and Methods72 consecutive patients with ACC were treated with fast neutrons, 66 after surgery, 6 for primarily unresectable disease, 43/66 for macroscopic residual disease, 23/66 for unresectable recurrent disease. 45/72 tumors were localized in the minor, 27 in the major salivary glands. T-stage was in 13 pts T2, in 33 T3, in 26 T4; positive nodes were in 10 pts, M+ in 15 pts. Mean tumor volume was 89 cm3. Neutron therapy was 15.03 Gy in 3 weeks with 1.67 Gy per fraction three times per week. Individual computer assisted treatment planning was performed based on CT and/or MRI, using bolus material if necessary. Target volume was the macroscopic tumor volume with a generous safety margin.ResultsComplete response was achieved in 28 pts, partial response in 35 pts. Local control was observed in 73.4% after a mean observation period of 36 months. Overall and recurrence free survival was 85%/81% at two years, and 58%/53% at 5 years (Kaplan-Meier). In univariate analysis tumor volume (>100 cm3), distant metastases, histologic subtype (solid) and neutron dose (<15 Gy) turned out to be significant parameters for predicting outcome, in multivariate analysis tumor volume and histologic subtype remained the only significant parameters. Acute morbidity was grade III/IV (EORTC/RTOG) in 6% for skin (desquamation), in 4% for mucosa (ulceration), late morbidity (grade III/IV) in one patient with local temporal brain necrosis.ConclusionAccording to this experience and taking into account the so far collected experience, fast neutron radiotherapy remains the treatment of choice for large and unresectable primary and recurrent ACC, and residual disease after surgery.

Relapse Analysis of Irradiated Patients Within the HD15 Trial of the German Hodgkin Study Group

PURPOSE To determine, in the setting of advanced-stage of Hodgkin lymphoma (HL), whether relapses occur in the irradiated planning target volume and whether the definition of local radiation therapy (RT) used by the German Hodgkin Study Group (GHSG) is adequate, because there is no harmonization of field and volume definitions among the large cooperative groups in the treatment of advanced-stage HL. METHODS AND MATERIALS All patients with residual disease of ≥ 2.5 cm after multiagent chemotherapy (CTX) were evaluated using additional positron emission tomography (PET), and those with a PET-positive result were irradiated with 30 Gy to the site of residual disease. We re-evaluated all sites of disease before and after CTX, as well as the PET-positive residual tumor that was treated in all relapsed patients. Documentation of radiation therapy (RT), treatment planning procedures, and portal images were carefully analyzed and compared with the centrally recommended RT prescription. The irradiated sites were compared with sites of relapse using follow-up computed tomography scans. RESULTS A total of 2126 patients were enrolled, and 225 patients (11%) received RT. Radiation therapy documents of 152 irradiated patients (68%) were analyzed, with 28 irradiated patients (11%) relapsing subsequently. Eleven patients (39%) had an in-field relapse, 7 patients (25%) relapsed outside the irradiated volume, and an additional 10 patients (36%) showed mixed in- and out-field relapses. Of 123 patients, 20 (16%) with adequately performed RT relapsed, compared with 7 of 29 patients (24%) with inadequate RT. CONCLUSIONS The frequency and pattern of relapses suggest that local RT to PET-positive residual disease is sufficient for patients in advanced-stage HL. Insufficient safety margins of local RT may contribute to in-field relapses.

Radiotherapy of splenomegaly

Purpose:Since the 20th century, radiotherapy (RT) has been used for treatment of symptomatic splenomegaly (SM). SM occurs in association with hematologic disorders. The purpose of this analysis was to determine the indication, treatment concepts, and efficiency of RT.Material and Methods: Clinical features, treatment concepts, and outcome data during the past 20 years were analyzed. Endpoints were pain relief, symptomatic and hematological response, and treatment-related side effects.Results:From 1989–2009, a total of 122 patients received 246 RT courses because of symptomatic SM. Overall 31 patients had chronic myelogenous leukemia (CML), 37 had chronic lymphocytic leukemia (CLL), 23 had osteomyelofibrosis (OMF), 17 had polycythemia vera (PV), 5 had acute myelogenous leukemia, 4 had idiopathic thrombocytopenic purpura (ITP), 3 had non-Hodgkin lymphoma (NHL), and 2 had multiple myeloma (MM). Patients were treated with 60Co gamma rays or 5–15MV photons. The fraction size ranged from 10–200 cGy and the total dose per treatment course from 30–1600 cGy. Significant pain relief was achieved for 74.8% of the RT courses given for splenic pain. At least 50% regression was attained for 77% of the RT courses given for SM. 36 patients died within 2 months due to the terminal nature of their disease. Of the RT courses applied for cytopenia, 73.6% achieved a significant improvement of hematological parameters and reduction of transfusion need. Notable hematologic toxicities were reported < EORTC/RTOG II°.Conclusion:The present analysis documents the efficacy of RT. In addition, RT as a palliative treatment option for symptomatic SM should not be forgotten.Einleitung:Seit Beginn des 20. Jahrhunderts hat die Radiotherapie (RT) ihren festen Stellenwert in der Behandlung einer symptomatischen Splenomegalie (SM). Die SM tritt bei hämatologischen Erkrankungen auf. Klinisch stehen Kapselschmerz sowie eine Zytopenie im Vordergrund. Die vorliegende Analyse untersucht Indikation, RT-Konzepte und die Effektivität der RT.Material und Methode:Patientendaten der letzten 20 Jahre wurden hinsichtlich klinischer Angaben, RT-Konzepte und Ergebnisse evaluiert. Endpunkte waren Schmerzfreiheit, hämatologisches Ansprechen nach RT sowie therapieassoziierte Nebenwirkungen.Ergebnisse:Zwischen 1989 und 2009 wurden 122 Patienten (79 Männer und 43 Frauen) mit insgesamt 246 RT-Serien behandelt. Folgende Grunderkrankungen waren Ursache für die Splenomegalie: CML (31), CLL (37), Osteomyelofibrose, (23), Polycyt haemia vera (17), AML (5), idiopathische Thrombozytopenie (4), Non-Hodgkin-Lymphom (3) und Plasmozytom (2) (Tabelle1). Die Behandlung erfolgte am Telekobalttherapiegerät oder am Linearbeschleuniger (5–15 MeV Photonen). Es wurden Einzelreferenzdosen zwischen 0,1–2 Gy und Gesamtreferenzdosen zwischen 3–16 Gy appliziert (Tabelle 2). Bei 74,8% der RT-Serien (74,8%), die aufgrund einer schmerzhaften Splenomegalie durchgeführt wurden, konnte eine Schmerzlinderung erzielt werden. Bei 77% der RT-Serien kam es zu einer Verkleinerung der Milz um bis zu 50% (Abbildung 1). 36 Patienten verstarben weniger als 2 Monaten nach Abschluss der RT im Rahmen der infausten Prognose ihrer Grunderkrankung. Bei 73,6% der RT-Serien kam es zu einer Verbesserung hinsichtlich Thrombozytopenien und die Transfusionsfrequenz nahm ab (Tabelle 3). Es wurden lediglich hämatologische Toxizitäten < II° (EORTC/RTOG) beobachtet.Schlussfolgerung:Die vorliegende Analyse belegt die hohe Effektivität der RT bei geringem Nebenwirkungsspektrum. Die RT der symptomatischen Splenomegalie sollte als wirksame palliative Option nicht in Vergessenheit geraten.

Zur Problematik dosimetrischer Verfahren bei der Bestimmung der Strahlendosis am Rektum in der HDR-Brachytherapie des Zervixkarzinoms

ZusammenfassungHintergrundBei der Brachytherapie des Zervixkarzinoms wird die Dosis am Rektum in der Regel mit Halbleiterdosimetern gemessen und für ausgewählte Punkte zum Beispiel gemäß ICRU-Report 38 rechnerisch bestimmt. Dieses Verfahren dient der Minimierung der Risikoorgandosis und damit der Vermeidung von Nebenwirkungen. Im Rahmen dieser Arbeit werden Dosismessungen und Berechnungen verglichen.MethodeBei 75 Applikationen wurden die gemessenen Rektumdosen retrospektiv analysiert und aus den Lokalisationsaufnahmen mit Hilfe eines graphischen Verfahrens die Dosiswerte an fünf Halbleitermeßpunkten im Rektum und am ICRU-Rektumreferenzpunkt ermittelt. Prospektiv wurde für elf intrakavitäre Einlagen die Dosis an verschiedenen Punkten am Rektum direkt bei der Rechnerplanung bestimmt, zusätzlich an spezifischen Referenzpunkten entsprechend dem lymphatischen Trapezoid nach Fletcher sowie die Beckenwandpunkte nach Chassagne.ErgebnisseDie retrospektive Auswertung ergab, daß 65% der mit dem graphischen Verfahren ermittelten Werte um ±30% von den gemessenen Werten abwichen. Ursachen hierfür waren: fehlerhafte Erfassung der räumlichen Lage des Applikators, keine orthogonale Aufnahmetechnik, fehlerhafte Kalibrierung der Halbleitersonden, Applikator- und Sondenverschiebungen zwischen Aufnahme und Applikation. Bei der prospektiven Gruppe lagen 95% der Abweichungen zwischen Messung und Rechnung in einem Intervall von ±40%. Die möglichen Fehlerquellen gleichen denen beim graphischen Verfahren, allerdings dürfte die Rekonstruktion der räumlichen Applikatorlage genauer sein, da sie die Geometrie der Punkte exakt übernimmt. In der retrospektiven Analyse wurden für den ICRU-Rektumreferenzpunkt 5,6±2,5 Gy, in der prospektiven Berechnung 6,1±1,6 Gy bestimmt. Die Standardabweichung der Meßwerte an spezifischen Referenzpunkten betrug im Mittel ±30%. Die mittlere Dosisverteilung war symmetrisch zur Körperachse, das heißt die Applikatorlage im Mittel körpermittig. Die Gründe für die relativ große Standardabweichung waren zum Beispiel Schwierigkeiten bei der Definition der Punkte, die Identifizierung auf den Röntgenaufnahmen und die unterschiedliche Applikatorlage.Schlußfolgerung enEine retrospektive Analyse führt zu einem höheren Fehler als eine prospektive; das graphische Verfahren sollte nur dann angewandt werden, wenn eine Rechnerplanung nicht möglich ist. Auffällig sind die Differenzen zwischen Rechnerplanung und Messung. Da diese Abweichungen nicht immer eindeutig zu erklären sind, sollten immer Messungen und Berechnungen durchgeführt werden, um einen Überblick über die Dosisverteilung im Rektum zu erhalten. Zusätzlich hat die Rechnerplanung den Vorteil, die Dosis an beliebigen Referenzpunkten ermitteln zu können.AbstractBackgroundDosage measurements in brachytherapy of cervix carcinoma are usually obtained with semiconductor dosimeters intrarectally and calculated using approximation methods for additional points, e. g. chosen according to ICRU Report 38. This procedure allows minimizing organ risk dosages and avoiding side effects. This study compares actual dosage measurements with computed approximations.Method sIn 75 applications the measured actual rectum dosage was analyzed retrospectively. Using graphic approximation methods in conjunction with the localization radiographs the expected dose values at 5 detector points of the intrarectal semiconductor dosimeter and at the ICRU rectal reference point were determined. Prospectively for 11 additional applications the expected dosage for various points within the rectum were computed during therapy planning and additionally for specific reference points corresponding to Fletcher’s lymphatic trapezoid and Chassagne’s pelvic wall points.ResultsThe retrospective evaluation showed that 95% of values determined by graphic approximation methods varied by as much as ±30% from measured values. Factors causing errors were incorrect assessment of the applicator’s spatial positioning, non-orthogonal radiographs, incorrect calibration of the semiconductor probe, movement of applicator and/or probe in the time between radiograph and application. In the prospective group 95% of deviations between measured and calculated values lay within an interval of ±40% (Figure 1). Possible sources of error could be similar to those in using the graphic approximation, although the reconstruction of spatial positioning of the applicator is possibly more exact. Doses determined at the ICRU rectal reference point were 5.6±2.5 Gy in the retrospective analysis and 6.1±1.6 Gy in the prospective study (Figure 2). The standard deviation of measured values at the specific reference points was ±30%. The mean dosage distribution was nearly symmetrical with regard to the body axis, i. e. to the applicator position. Reasons for the relatively large standard deviation are e. g. difficulties in defining the reference points as well as in identifying them on the radiographs, also differences in applicator positioning.ConclusionsThe retrospective analysis led to a larger error than the prospective one. The graphic approximation method should only be utilized when computer-assisted treatment planning is not possible. Conspicuous are the differences between values obtained in computer planning and actual measured values. As these deviations cannot always be explained unequivocally, both computation and measurement should always be conducted in order to obtain an adequate survey of dosage distribution within the rectum. Computer planning offers the additional advantage of determining the dose at various other reference points.BACKGROUND Dosage measurements in brachytherapy of cervix carcinoma are usually obtained with semiconductor dosimeters intrarectally and calculated using approximation methods for additional points, e.g. chosen according to ICRU Report 38. This procedure allows minimizing organ risk dosages and avoiding side effects. This study compares actual dosage measurements with computed approximations. METHODS In 75 applications the measured actual rectum dosage was analyzed retrospectively. Using graphic approximation methods in conjunction with the localization radiographs the expected dose values at 5 detector points of the intrarectal semiconductor dosimeter and at the ICRU rectal reference point were determined. Prospectively for 11 additional applications the expected dosage for various points within the rectum were computed during therapy planning and additionally for specific reference points corresponding to Fletchers lymphatic trapezoid and Chassagnes pelvic wall points. RESULTS The retrospective evaluation showed that 95% of values determined by graphic approximation methods varied by as much as +/- 30% from measured values. Factors causing errors were incorrect assessment of the applicators spatial positioning, non-orthogonal radiographs, incorrect calibration of the semiconductor probe, movement of applicator and/or probe in the time between radiograph and application. In the prospective group 95% of deviations between measured and calculated values lay within an interval of +/- 40% (Figure 1). Possible sources of error could be similar to those in using the graphic approximation, although the reconstruction of spatial positioning of the applicator is possibly more exact. Doses determined at the ICRU rectal reference point were 5.6 +/- 2.5 Gy in the retrospective analysis and 6.1 +/- 1.6 Gy in the prospective study (Figure 2). The standard deviation of measured values at the specific reference points was +/- 30%. The mean dosage distribution was nearly symmetrical with regard to the body axis, i.e. to the applicator position. Reasons for the relatively large standard deviation are e.g. difficulties in defining the reference points as well as in identifying them on the radiographs, also differences in applicator positioning. CONCLUSIONS The retrospective analysis led to a larger error than the prospective one. The graphic approximation method should only be utilized when computer-assisted treatment planning is not possible. Conspicuous are the differences between values obtained in computer planning and actual measured values. As these deviations cannot always be explained unequivocally, both computation and measurement should always be conducted in order to obtain an adequate survey of dosage distribution within the rectum. Computer planning offers the additional advantage of determining the dose at various other reference points.

Treatment results of fast neutron irradiation in soft tissue sarcomas.

PurposeSurgery is the standard treatment of soft-tissue sarcomas. Adjuvant radiotherapy with photons after less radical resection can improve local control. The rate of tumor control achieved in patients with G1 and G2 soft tissue sarcomas incompletely resected and treated postoperatively with neutron irradiation is similar to that seen in patients undergoing complete tumor resection and adjuvant photon irridiation.Patients and MethodsAt the Department of Radiotherapy and Radiation Oncology of the University of Münster, 61 patients with soft tissue sarcomas were irradiated postoperatively with fast neutrons. Mainly tumors of low or intermediate malignancy (R0; 27%; R1, 21%; R2, 52%) were treated. Malignant fibrous histiocytoma, liposarcoma, and neurogenic sarcomas dominated. 46 patients were irradiated with fast neutrons alone, and 15 patients were treated with mixed beam therapy (photons and neutrons).ResultsThe median follow-up period was 44 months. Overall five-year survival probability analysed by Kaplan-Meyer method was 42.5%. The local control rate was 57.7%. 15 patients showed complete remission, 18 patients had a partial remission. Only 11% of the patients showed grade III and IV side effects during neutron irradiation.ConclusionNeutron irradiation is efficocious in treating highly and intermediately differentiated soft tissue sarcomas. The result of surgical resection seems to be a very important prognostic factor for patients with soft tissue sarcomas.

Monitorbeurteilung digitalisierter und nachbearbeiteter Feldkontrollaufnahmen im Vergleich zu konventionellen Feldkontrollaufnahmen am Röntgenschaukasten

ZusammenfassungZielBeurteilung der Bildqualität und Detailerkennbarkeit digitalisierter und nachbearbeiteter Feldkontrollaufnahmen am Computermonitor im Vergleich zum bisherigen Standard, der Beurteilung konventioneller Feldkontrollaufnahmen am Röntgenschaukasten.Material und MethodeKonventionelle Feldkontrollaufnahmen von drei unterschiedlichen Tumorregionen (zehn Becken-, zehn Schädel- und zehn Wirbelsäulenaufnahmen) wurden acht Untersuchern in drei verschiedenen Varianten präsentiert: konventioneller Film am Röntgenschaukasten (Konv), digitalisierte Feldkontrollaufnahme ohne Nachbearbeitung (Dig-1), digitalisierte Feldkontrollaufnahme mit einfacher Bildnachbearbeitung (Dig-2) am Computermonitor. Die subjektive Bewertung der Bildqualität, die Detailerkennbarkeit und der Zeitaufwand für die Beurteilung am Röntgenschaukasten im Vergleich zur Monitorbeurteilung wurden durch einen gezielten Fragebogen ermittelt. Die Untersucher konnten aus den vorgegebenen Antwortmöglichkeiten 1=viel besser bis 5=viel schlechter wählen. Zusätzlich mußten die Untersucher klar definierte knöcherne Referenzpunkte sowohl am konventionellen Film am Röntgenschaukasten als auch am digitalisierten, nachbearbeiteten Bild (Dig-2) am Computermonitor einzeichnen. Als objektives Maß für die Detailerkennbarkeit anatomischer Strukturen wurde die Streuung der von den unterschiedlichen Untersuchern eingezeichneten Punkte berechnet.ErgebnisseDie Bildqualität der digital nachbearbeiteten Bilder am Monitor wurde statistisch signifikant besser als jene der konventionellen Filme am Röntgenschaukasten beurteilt (Becken 78%, Wirbelsäule 62%, Schädel 45% besser). Ebenso wurde die Detailerkennbarkeit der digital nachbearbeiteten Bilder im Vergleich zu den konventionellen Filmen beurteilt (Becken 81%, Wirbelsäule 57%, Schädel 40% besser). Die größte Verbesserung der Bildqualität und detailerkennbarkeit bei der Beurteilung am Monitor konnte für das Becken ermittelt werden, jener Region mit erfahrungsgemäß schlecht beurteilbaren Feldkontrollaufnahmen. Im Gegensatz dazu wurde die Bildqualität von digital nicht nachbearbeiteten Bildern im Vergleich zu konventionellen Filmen schlechter beurteilt (Becken 69%, Wirbelsäule 53%, Schädel 71% schlechter). Der Zeitaufwand für die Beurteilung digital nachbearbeiteter Bilder am Computermonitor wurde vor allem für das Becken kürzer eingeschätzt als am Röntgenschaukasten (Becken 68%, Wirbelsäule 26%, Schädel 8% kürzer). Als objektivierbares Maß für die verbesserte Bildqualität und Detailerkennbarkeit zeigte sich für das Becken eine signifikant kleinere Standardabweichung der eingezeichneten Referenzstrukturen bei Dig-2-Aufnahmen im Vergleich zum konventionellen Film. Für die Wirbelsäule und den Schädel fanden sich keine signifikanten Unterschiede.Schlußfolgerung enDie Präsentation von digitalisierten und nachbearbeiteten Feldkontrollaufnahmen am Computermonitor führte trotz primär schlechter Bildqualität digitalisierter Aufnahmen durch entsprechende Bildnachbearbeitung zu einer rascheren Beurteilung und gleichwertigen bis besseren Bildqualität sowie Detailerkennbarkeit im Vergleich zur Beurteilung konventioneller Filme am Röntgenschaukasten.AbstractPurposeJudgement of image quality and detail recognition of digitized and post-processed portal films presented on a computer monitor compared to the present standard, conventional portal films presented on a light-box.Material and MethodsConventional portal films of 3 different tumor sites (10 pelvis, 10 cranium, 10 vertebral column) were presented to a panel of 8 observers in 3 different manners: conventional film presented on a light-box (Conv), digitized non-post-processed images (Dig-1) and digitized post-processed images (Dig-2) presented on a high-resolution computer monitor. Subjective judgement of image quality, detail recognition and time requirement of conventional films compared to monitor presentation were evaluated using a 5-scaled questionnaire (from 1=much better to 5=much worse). Furthermore the observers had to point out predefined anatomical bony structures on the conventional films (Conv) as well as on the digitized post-processed images (Dig-2). Standard deviations of the landmarks outlined by 10 different observers were used as a criterion of objective detail recognition (Figure 1).ResultsImage quality of digitized post-processed images presented on the computer monitor was judged statistical significant better than of conventional films (pelvis 78%, vertebral column 62%, cranium 45% better) (Figure 3). Similar results were found for comparison of detail recognition: digitized post-processed images were scored better for pelvis in 81%, for vertebral column in 57%, for cranium in 40% (Figure 4, Table 1). Most benefit from portal film enhancement was found for pelvic images, where portal films are known to be of poor image quality (Figure 2). In contrast image quality of non-processed digital images compared to conventional films was graded worse (pelvis 69%, vertebral column 53%, cranium 71% worse) (Figure 4). Digital post-processed images were especially for the pelvis judged to require less time (pelvis 68%, vertebral column 26%, cranium 8% less time requirement) (Figure 5). For the pelvis a statistical significant decrease of standard deviations was found for Dig-2 compared to conventional films, indicating an objective increase of image quality and detail recognition (Table 2). In case of vertebral column and cranium no significant differences were evaluated (Table 3).ConclusionsDigitized enhanced portal films presented on a computer monitor resulted in a quicker assessment and equal to better image quality as well as detail recognition compared to conventional films. Non-processed digitized images were judged to be of less image quality.