The hazy dawn of brachytherapy.

The discovery of radium by Pierre and Marie Curie in December 1898 opened a new era in science and within a few years provided medicine with a new means of tumor treatment. Their personal contribution to the start and early development of clinical applications should not be overlooked. The Curies did not limit their support to providing radium sources to medical pioneers but took a deep interest in the horizons of radium therapy.

[From X-rays to radioactivity and radium. The discovery and works of Henri Becquerel (1851-1908)].

The discovery of radioactivity was the outcome of a methodical experimental study achieved by Becquerel. He continued his discovery with studies which give evidence of his scientific and experimentative mind. These studies explored the nature and properties of the emitted radiation and brought basic data to the disintegration theory.

Characterization of two sulfate-reducing bacteria from the gut of the soil-feeding termite, Cubitermes speciosus.

Two sulfate-reducing bacteria (SRB) were isolated from a mixed culture enriched with benzoate obtained from gut homogenate of the soil-feeding higher termite, Cubitermes speciosus. The organisms were vibrioid rods, staining Gram-negative, which performed incomplete substrate oxidation. They differed in several features.

Similar effects on murine haemopoietic compartment of low dose rate single dose and high dose rate fractionated total body irradiation. Preliminary results after a unique dose of 750 cGy.

This study was designed to compare two different modalities of TBI which are currently used in clinical practice. The same dose of 750 cGy was given to CBA mice either in a single dose at a low dose rate (4 cGy min-1) (STBI) or in a fractionated regimen (six fractions of 125 cGy three times a day) at a higher dose rate (25 cGy min-1) (FTBI). After TBI completion we simultaneously studied the in vivo radiation response of bone marrow cells, two murine bone marrow clonogenic cells (CFU-S and GM-CFC) and peripheral blood lymphocytes and granulocytes for a period of 1 month.

[Biological equivalency of high single doses used in intraoperative irradiation].

Unlabelled: Intra-operative radiotherapy is being used more and more frequently; this raises the problem of the equivalence of these large doses delivered in a single fraction, especially when a second line, complementary external irradiation is planned afterwards. The linear quadratic (LQ) model is probably the most convenient way to compare 2 irradiation schedules delivered with different doses per fraction. However, in the case of intra-operative radiotherapy, one should question the use of the LQ equation; this model actually predicts a continuous bending of the survival curve, while most experimental curves show a trend towards exponential at high dose levels.

Clinical basis for TBI fractionation.

Most available clinical data strongly suggest a sparing effect of TBI fractionation for the lungs, liver, lens, the growth cartilage and, perhaps the prepubertal ovary; the usual fractionated TBI regimens, delivering from 12 to 15 Gy, appear to be constantly less toxic than the "standard" 10 Gy single dose TBI scheme. However, there is also some clinical suggestion, essentially coming from the T-depleted graft experience, that the largely used 12 Gy fractionated scheme (6 X 2 Gy) might be less effective than the standard 10 Gy single dose TBI for leukemia cell killing and for eradication of the recipient bone marrow. Additional clinical data, ideally coming from well designed randomised trial or from careful large-scale retrospective evaluations, should help to optimize the TBI delivery.

Single dose versus hyperfractionated total body irradiation before allogeneic bone marrow transplantation: a non-randomized comparative study of 54 patients at the Institut Gustave-Roussy.

At the Institut Gustave-Roussy (IGR), from January 1982 to December 1986, 54 patients received total body irradiation (TBI) as a part of the conditioning regimen before allogeneic bone marrow transplantation. The patients were non-randomly assigned to either single dose TBI (STBI) (31 patients receiving 10 Gy at a 4.5 cGy/min dose rate, 8 Gy to the lungs) or to a hyperfractionated scheme (HTBI) (23 patients receiving 13.

Expression of the dose rate effect in clinical curietherapy.

The role of the dose rate on the biological effect can be assessed by a simple formula involving only two parameters related to the repair ability (alpha/beta) and to the repair kinetics (repair time constant t or repair half time Tr). The result of the computation provides a value in which the dose rate is taken into account along with the physical dose. It can be expressed by: the ERD (extrapolated response dose), the equivalent dose at a constant dose rate used as a reference, or by the equivalent dose for a conventionally fractionated dose (5 x 2 Gy/week).

Unusual localization of cutaneous chronic graft-versus-host disease in the radiation fields in four cases.

Chronic graft-versus-host disease (GVHD) is a very heterogeneous entity with variable clinical expression. The pathophysiology involves autoimmune disorders and features of fibrosis. Four patients transplanted for severe aplastic anaemia conditioned with cyclophosphamide and thoraco-abdominal irradiation developed skin scleroderma specifically localized in the irradiation fields.

[Blood amylase: a biological marker in irradiation accidents? Preliminary results obtained at the Gustave-Roussy Institut (GRI) and a literature review].

The retrospective evaluation of the dose after an irradiation accident is of paramount importance; it allows an adequate selection of patients and the most appropriate treatment can then be proposed. Classical physical dosimetry often lacks precision for dose assessment in such accidents. Cytogenetics, usually more reliable, is not 100% accurate and cannot be used in some particular instances.

Applicability of animal tumor data to cancer therapy in humans.

The problem of applying experimental tumor studies to clinical cancer therapy is a complex one. The radiotherapy literature contains many examples of premature efforts to apply laboratory observations to the clinic, and many examples of failures to adequately consider animal tumor observations in the design of clinical studies. This review covers three areas: tumor hypoxia, where clinical trials based on animal tumor data have been conducted with radiosensitizers, hyperbaric oxygen, and systemic oxygen carriers; dose fractionation, where current trials of hyperfractionation are based in part on animal tumor studies; and chemo-radiotherapy, where clinical trials are only beginning to exploit concepts developed in animal tumor systems.

An approach to the interpretation of clinical data on the tumour control probability-dose relationship.

A conventional statistical model allows predicting the sterilisation rate as a function of dose. However, the computation requires data on biological parameters (proportion of clonogenic cells, survival per fraction, multiplication rate) which are inaccessible for human tumours. The curative dose 50% (TCD50) can be used as a synthesis of these parameters and its significance for the response-dose relationship of a population of tumours of uniform radiosensitivity is discussed.

Late toxicity of radiotherapy in Hodgkin's disease. The role of fraction size.

From 1972 to 1976 patients at the Gustave Roussy Institute were irradiated for Hodgkin's disease using a modified fractionation schedule (3 fractions of 3.3 Gy per week) for operational reasons. From 1964 to 1971 and from 1977 to 1981, a more conventional regimen (4 fractions of 2.

[Comparison between single-dose and hyperfractionated total-body irradiation for the conditioning of allogenic grafts of the bone marrow. A retrospective study of 54 patients with malignant hematologic diseases].

The present study is a retrospective analysis of 54 patients with hematological malignancies who were treated by total body irradiation (TBI) and allogenic bone-marrow transplantation from 1982-1986. Patients were not randomly assigned to receive either single dose total body irradiation (STBI) (10 Gy x 1-4 cGy/min-lung dose 8 Gy) or hyperfractionated total body irradiation (HTBI) (1,20 Gy x 11-3 fractions/day-lung dose 9 Gy). Thirty one patients received STBI and 23 a HTBI regimen.

Blood cell kinetics and total body irradiation.

The early response of blood cells to irradiation has been studied in leukemia patients who received total body irradiation (TBI) prior to cyclophosphamide and bone marrow transplantation. After a single session treatment (10 Gy in 4 h) the most dramatic variation was observed in the granulocytes. At the end of the irradiation their concentration was 2 to 6 times higher.

Biologic and anatomic problems of lung shielding in whole-body irradiation.

Lung shielding by lead blocks for reducing the dose to the lungs in whole-body irradiation results in relative protection of the leukemia cell population. The consequence is acceptable if the dose reduction is moderate (from 10 to 8 Gy) and if the shielded volume amounts to a small fraction (5%) of the body weight. The suggestion was made that certain limits should be put on the extent of shielding, so that the shielded lung fraction represents only 60% of the total lung volume.

[Ultrasonic, arteriographic and anatomopathological correlation in 59 cases of carotid atherosclerosis].

This study was carried out on 49 patients who underwent an ultrasound study by continuous Doppler and echotomography B real-time, an angiography of supra-aortic arteries, and a carotid endarterectomy. Thirteen had had transient ischemic attacks and 20 a stroke. A quantification of the carotid stenosis in 4 stages was established for each method.

Interstitial thermoradiotherapy: a technical and clinical study of 29 implantations performed at the Institut Gustave-Roussy.

In 1981, a protocol was developed at the Institut Gustave-Roussy, combining interstitial hyperthermia and brachytherapy. Twenty-nine implantations were performed in 23 patients. All the lesions except three were located in previously irradiated areas.