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Compared to the other chemotherapeutic preparations discussed today, cyclophosphamide in combination with radiotherapy is a relatively unproblematic substance. Despite the great number of experimental and clinical data, the evaluation does not prove an advantage of the combined therapy with cyclophosphamide and irradiation as against radiotherapy alone in local tumor treatment. This should give occasion to further experimental investigations in adequate models. On the other hand, the practice of combined treatment with irradiation and preparations containing cyclophosphamide should be reconsidered for those cases where local control of a tumor is the principal therapeutic aim.

Curative radiation therapy in the treatment of non-Hodgkin lymphomas requires a technique of irradiation taking into account as far as possible the complicated conditions of target volumes and critical organs. Technical problems and clinical necessities having been exposed in detail, the methods of irradiation developed till now are discussed. With the possibilities of simplification and individualization of these methods, combined with modern procedures for irradiation planning, a new technique was developed, whose possibilities and limits are represented.

The authors present a new method for the interstitial therapy working with an Ir-192 source which is displaced step by step. After having been fed with the tumor parameters, the computer calculates for every stopping point the duration of stay of the source which provides a threedimensional optimization. The practical application of the method is discussed and the optimization procedure is compared with other similar methods.

The results from 198 own patients with squamous cell carcinoma of the vulva, having undergone surgical treatment and postoperative irradiation with high-energy electrons and photons, are represented and analysed. The own results are compared to results from the literature obtained by means of larger collectives and of various techniques. A differentiated concept for therapy is presented, taking into account the prognostically important parameters, and integrating surgical and radiation treatment.

The principle and practical application of an afterloading system for interstitial therapy is reported. The system works with a single Ir-192 source with high dose rate and achieves the optimum dose distribution by gradual displacement and variable position times. A specially developed computer program serves to calculate the stopping times of the source. The implantation is performed with hollow needles made of refined steel, which are held in parallel position by means of jigs fixed to the patient. 28 patients with 36 tumors have been treated. The dose was determined according to the experiences in gynecologic afterloading therapy with high dose rate sources and dosage prescriptions in teletherapy. The authors present the therapeutic results of this pilot study, discuss the new system and show practicable possibilities for further development.

Between 1970 and 1980, 339 patients with Hodgkin's disease in stages IA to IIIB were treated at the Department of Radiotherapy, University of Essen, FRG. 65 patients (group A) were irradiated using a multiple-field-technique with cobalt-60, 110 patients (group B) with mantle fields, inverted Y or paraaortic extended fields given with 5.7 MeV photons. There were no significant differences between the cumulative survival times, local and marginal recurrences. However, the recurrence rates of unirradiated lymph node regions were different, mainly due to absent or given paraaortic treatment. The presence of initially normal blood parameters (BSR, relatively lymphocyte count, haptoglobin, copper, iron) is of high prognostic value. Combined, they allow a correct prognosis as to the five year recurrence rate in up to 98% of cases. The prognostic precision of initially pathologic values was considerably reduced, even if a normalization had occurred after one year from the initiation of treatment.

83 patients with small-cell bronchial carcinomas were treated with a combination of cytostatic chemotherapy ("ACO II" = adriamycine, cyclophosphamide, vincristine) and irradiation of the mediastinum, the tumor umbra and the affected hilum with a focal dose of 30 Gy administered within a period of three to four weeks. During the same period, those patients presenting the favorable initial stage "limited disease" (LD) were additionally submitted to a prophylactic total brain irradiation with a dose of 30 Gy. 42 among 55 patients of stage LD had a complete remission. Among these 42 patients, fourteen had an intrathoracic recurrence, nine of them within the irradiation field. A cerebral recurrence after prophylactic brain irradiation was found in five of 42 cases. The conclusion is drawn that the irradiation dose which has to be administered into little intrathoracic fields must be increased. A dose of 45 Gy within 4 1/2 weeks is desirable. It seems that a prophylactic brain irradiation is only efficient in patients with a favorable prognosis (LD, CR).

The frequency of local recurrences in keratoid squamous cell carcinomas of the oral cavity is analyzed in view of the following criteria: Irradiation technique, volume of the primary tumor, irradiation parameters considering the factor of dose and time. The values of the dose, measured by ret, were calculated using the Ellis-formula modified by Gabriel-Jürgens et al. A focal dose of 1,700 ret is recommended for Stage T1 carcinomas of the tongue, a dose of 1,900 ret for the stages T2 and T3. The importance of the concept of nominal standard dose is emphasized with regard to its clinical application. Surgery seems to be superior to the renewal of radiation therapy in the treatment of recurrences.

An afterloading system for the intracavitary radiotherapy is described which works with a unique radiation source of 10 Ci 192Ir moving in steps of 1 cm. The times during which the source stops can be determined at a control panel. By using an intermediate piece of 10 cm, a total course of the source of 20 cm can be obtained. The course of the source can be calculated individually by a computer program. This program even takes into consideration an additional deep therapy if the position of the deep therapy field in the target volume is known. This method allows to adapt the total isodoses very precisely to the course of the tolerance doses.

The subject of this study were non-seminomatous testicle tumors with cerebral formation of metastases. Despite the relatively low radiosensitivity of the primary tumors and their regional metastases eighteen of twenty patients were free of symptoms, and a complete regression of the intracerebral tumors was shown by computed tomography and/or scintigraphy in ten of twenty cases. This regression was obtained within two or three weeks by an irradiation of the skull with a focal dose of 30 to 40 Gy. Due to the small number of patients (20), it was not possible to demonstrate a statistically different receptiveness of the cerebral metastases according to their histological subentity. Because of the subjective stress, the duration of radiotherapy should be as short as possible (e.g. 30 Gy in 10 fractions over a period of two weeks). In our opinion, irradiation is clearly indicated in case of testicle teratomas with cerebral formation of metastases. Practically the only contra-indications are a strong intracranial hypertension as well as hyperkinesia. The entire prognosis of the patient, however, is not determined by the cerebral formation of metastases but by the pulmonary metastatic extension, so that radiotherapy is an important palliative factor with regard to the survival time of these patients.

By treating eleven patients with an individual large field therapy adapted to the single stage and subsequent chemotherapy (Leukeran), we obtained an average survival time of 42,6 months (living patients) and 37,6 months (patients died), respectively. Late complications of this therapy were not observed, the tolerance was good. In case of recurrence after this treatment, the reserves of bone marrow seem to be too small to allow an aggressive chemotherapy.

The authors compare the results of two methods of the upper and lower system irradiation in case of Hodgkin's disease with respect to the spinal marrow. The frequency of radiomyelitis is opposed to the frequency of Hodgkin-specific alterations of the spinal marrow. 74 patients were submitted to telecobalt irradiations the dosage of which was below the tolerances known for the spinal marrow. Two of them presented a radiomyelitis and two a paraplegia of Hodgkin in the irradiated region. One paraplegia caused by the formation of a tumor developed in a region next to the irradiation field; certainly this region would have been affected by a higher dosed large-field irradiation of the spinal marrow. The application of the large-field methods in 61 patients did not cause any radiomyelitis in spite of doses which were higher than the tolerance doses for the spinal marrow of Franke. Hodgkin- specific infiltrations of the spinal canal were also not observed. The large-field method can also be recommended because it seems to offer a larger therapeutic field between the risks of spinal Hodgkin manifestations and radiomyelitis.

A survey is given of the mathematical and empirical methods allowing to compare different chronological dose distributions; their possibilities and limits are described. The experimental bases of hyper- and superfractionation and the clinical experiences gained hitherto with multiple daily irradiations are communicated; radiotherapy with high individual fractions and long term irradiation are shortly explained. Finally some hints are given for the further development and the practical use of not typical fractionation schemes.

A new technique for radiation therapy in stage I and II carcinoma of the ovary is presented, intended to cover as homogeneously as possible the paraaortic, subdiaphragmatic and intradiaphragmatic areas of the direct lymphatic pathways as well as the small pelvis. This technique permits to deliver a dose of up to 46 Gy to this target volume, adjuvant chemotherapy being regarded as a convenient complement of such localized radiation therapy. Using a modern interactive system for treatment planning, a combination of 2 a.-p./p.-a. and 2 lateral fields is developed. Individually shaped circular satellites and rectangular satellites serve for protection of the liver and small intestine. Good reproducibility is obtained by means of the simple geometrical form of the fields and satellites.