When William Coolidge developed the hot-cathode tube, deep therapy treatment could be performed. Further investigation led to the development of a high-voltage unit known as the betatron. As radiation therapy progressed, the development of cobalt therapy units and linear accelerators revolutionized patient treatment and curative methods for cancer. Japan stamp carried a surtax to help fight cancer. The drawing symbolizes radiation focusing on a deep-seated cancer in the patient.
Turkey stamp features a cobalt therapy machine.
The crab is one of the most common symbols of cancer. The unit is capable of rotating around the patient and pinpointing cancers from various angles. This stamp was issued by Japan as part of its anti-cancer movement. Funds from the sale of this stamp would help to fight cancer. This postcard and stamp feature a modern linear accelerator for cancer treatment in radiation oncology.