[en] Loco-regional recurrence in squamous cell carcinoma of the head and neck can occur at the site of the original primary tumour or in the marginal zone at its periphery. While nodal recurrence may occur in previously involved nodes or in uninvolved nodes within or outside the treatment volume. The exact site of failure was determined in 89 patients treated with radical radiotherapy for carcinoma of the head and neck. Of 73 patients who failed at the primary site 71 (97%) did so within the site of the original tumour; only two patients developed a marginal recurrence. Of the 30 (93%) patients with N1-3 disease who later showed failure in the lymph nodes, 28 (93%) did so at their original site of disease. These results support the view that when radiation fails it usually does so in the centre of the tumour. In order to improve our results we need to deal with radioresistance at the site of mass disease. Ways of approaching this include the combination of surgery with radiotherapy, the addition of a sensitiser or an increase in the dose to the tumour mass by boosting a 'mini' volume using conformal techniques

[en] Short note. 9 refs

[en] Trials have been undertaken to investigate whether irradiation in hyperbaric oxygen would give better clinical results in radiotherapeutically treated cancer patients. Until now, the results seem hardly promising

[en] The different forms of radiotherapy and chemotherapy used in the treatment of malignant tumours are briefly outlined. A more detailed review is given of the use since 1960 of chemical radiosensitizers of the hypoxic cells in tumours. Hypoxic cell radiosensitizers have an advantage over alternative methods for improving the effect of radiotherapy since hypoxic cells exist in considerable concentrations in tumours and in only small concentrations in normal tissues. Five different treatment regimes using the radiosensitizer, misonidazole, are given. The results of some randomized controlled clinical trials to date have shown advantage in using misonidazole but other trials have shown no benefit. (U.K.)

[en] Experience with hyperbaric oxygen in radiotherapy now extends over 25 years. In randomized controlled clinical trials significant benefit has been shown in the treatment of head and neck tumours and some trials in carcinoma of cervix. Improvement has been shown in one trial in carcinoma of bronchus but not in any trials in carcinoma of bladder. The results of hyperbaric oxygen must now be compared with other methods currently under trial for improving the results of radiotherapy. Clinical work with the hypoxic cell sensitizers began in 1973 with metronidazole and in 1974 with the more promising compound, misonidazole. It has been shown that there is a satisfactory penetration of the drug into tumours. Sensitization of hypoxic cells in man has been demonstrated as well as increased effect in tumours when single doses are employed. Neurotoxicity restricts the total dose which may be given. Randomized controlled clinical trials using misonidazole are now underway. (author)

No abstract available

[en] Despite an enormous laboratory and clinical effort, advance in patient care has not yet been achieved by hypoxic cell radiosensitization. The reasons for this are considered and suggestions made as to the future direction of work in this important field. 41 refs

[en] After outlining the main variables in radiotherapy, a brief article describes the preliminary results obtained with continuous, hyperfractionated, accelerated radiotherapy (CHART). Patients with advanced squamous cell cancer in the head and neck region and with locally advanced carcinoma of the bronchus received this radiotherapy which was given three times daily for a continuous period of 12 days. The promise of this pilot study is now to be tested for these cancers in multi-centre randomised trials. (UK)

[en] A high standard of radiotherapeutic practice must be sought in all phases of management of a patient with malignant disease. Radiation therapy must be appropriately chosen and integrated with surgery, cytotoxic chemotherapy and all other modes of treatment. The most suitable technique with a dose, fractionation and time regime must devised and executed with technical and personal care. Follow-up to truly assess tumor control and morbidity is essential so as to guide the management of future patients. To achieve this in Europe great reliance is placed upon the training and qualification of the therapist and staff. High standards are applied to the professional qualifications for radiation physicists, nurses and technical staff. In the countries belonging to the European economic union, a new Diploma in Radiation Therapy has been established to be a standard for consultant practice through all the countries included. The European Organization for Research and Treatment of Cancer has recently initiated a quality control study in some of the centers included in the Radiotherapy Group. A preliminary report has just appeared on the results of the clinical and dosimetric studies in 8 centers placed in 5 European countries

[en] The clinical trials of the use of hyperbaric oxygen in radiotherapy conducted by the Medical Research Council's working party have shown that local cure and survival can be improved in head and neck and cervical cancer. Evidence for benefit has been presented in carcinoma of bronchus, but none has so far been found in carcinoma of the bladder. Although hyperbaric oxygen has produced increased effect upon normal tissues as well as upon tumour, a real improvement in therapeutic ratio appears to be present. The future use of hyperbaric oxygen in radiotherapy will depend upon a comparison of effectiveness with other methods now being tested to improve radiotherapy. The trials have yielded much fundamental and clinical data of general relevance in the radiotherapy of malignant disease. (author)