In the dissertation of radiologist Catharine van Raamsdonk of 1921 , a description is given of the radiation treatment of cancer of the uterine cervix in the Netherlands Cancer Institute (NKI). She describes the development of this radiation treatment in the period 1915 to 1920.
In 1915, the first patients are treated with radium only. For this purpose 100 mg radium bromide is available. This is distributed over 5 brass tubes with a wall thickness of 0.5 mm. The tubes are arranged on a small plank or grouped together in a small bundle, packed in rubber and placed in the vagina against the tumour. The radiation is therefore filtered by 0.5 mm brass and 2 mm rubber and the application time was 12 hours. The patient was often irradiated 2 x 12 hours with a few days in between. After 3 to 4 weeks, the treatment was repeated. Shortly after the end of the application, symptoms were reduced and bleeding stopped. However, the patients returned complaining of pain due to infiltration of the parametrium. The radiation did not penetrate sufficiently deep. A solution was found by the removal of as much tumour tissue as possible by excochleation (curettage of the uterus) and by the application of zinc chloride. After this, the radium could be introduced deeper into the vagina.
Later radium was combined with X-ray irradiation of the abdomen, directed at the uterus and surrounding areas. The radiation needed to be as hard as possible and the high voltage was set at a maximum of 140 kV at 3mA. The source-skin distance was 18 cm and 5 mm of aluminium and 5 mm of leather was used as a filter. The leather served to attenuate the soft scatter radiation from the aluminium filter. The dose was ca. 16H as measured by a Holtzknecht meter. This technique was later extended with a multiple field irradiation through a sacral field in addition to the abdominal and vaginal treatments. The aluminium filter was replaced by 0.5 mm of zinc. A greater depth dose was achieved than was possible using only radium. In order to fix the radium in the tumour cavity, a vaginal mould was made from thermoplastic material. This was softened in hot water and then moulded in the vagina. In this mould, the radium is fixed in a stable position in which it is kept at a distance from the healthy tissue of bladder, vagina and rectum.
In 1919, when improved X-ray machines came into use, treatment with only X-rays became more usual. The voltage is 170 kV with 2 mA, the source-skin distance is 20 cm and the filter consists of 0.5 mm zinc and leather.
For an extensive description of the development of the radiation technique for treatment of the uterine cervix, the reader is referred to the dissertation of Catharina van Raamsdonk.