On September 18, 1940, during the administration of President Augusto Boyd, the new facilities of the National Radiologic Institute were inaugurated, giving it its own building.

In 1965, a more active role in the battle against cancer is started, when the latest advancements of the time are applied in the detection and treatment of this illness.

On 1980, the institution begins relations with the government of Japan, that was interested on the treatment of cancer in Panama, and by which a donation of medical and surgical equipment, including ultrasound, X-rays, and others are acquired.

On 1984, by law 11, the National Oncologic Institute (Instituto Oncologico Nacional) Juan Demóstenes Arosemena is created.

The TPS allows a maximum of four shielding blocks per field to be taken into account when calculating treatment times and dose distributions.

Shielding blocks are used to protect healthy tissue of patients undergoing radiotherapy at the Institute, as is the normal practice.

The team was complemented by a physicist from the Pan American Health Organization (PAHO), also at the request of the Government of Panama.

The error was on the data entry, using a protocol not validated to enter more shielding blocks, that resulted in increased dose in the treatment.