Falling into two categories, i.e. proton rays and heavy ion rays, particle rays carrying charges can be adopted to treat cancer at a certain depth. However, it would be useless for cancer that is beyond such a depth. Both proton rays and heavy ion rays are easy to center on the cancer focus.
～Comparison between 2 types of particle rays, i.e. proton rays and heavy ion rays～
Particle ray therapy employs both proton rays and heavy ion rays (carbon ion rays) that are capable of emitting high energy to kill cancer cells once reached the target focus.
By taking advantage of this characteristic, given the same dosage, the treatment effects of proton rays and heavy ion rays are respectively about 1.1 times and 3 times that of X-rays.
Although almost identical with X-rays and γ-rays in respect of cancer cell extermination, proton rays are more concentrated.In terms of treatment effect and invasion, it is reported that proton ray therapy basically equals to tomotherapy.
Comparing with proton rays, heavy ion rays are relatively advantageous from the perspective of finish position tolerance and transversal expansion. Moreover, the latter is 3 times or above than the former with respect to the biological result of cancer cell elimination. Heavy ion rays are also potent in treating tumors with low oxygen concentration. By the way, accredited to high dosage concentration, such a type of ray is superior in attacking cancer focuses in millimeters. Nevertheless, high cost slows down its pace of popularization.
Particle ray therapy
|Dosage concentration||Comparing with common X rays, with better dosage concentration, damage caused to nearby internal organs is considerably brought down|
|Cell-killing effect||Comparing with common X rays|
|Effect exerted upon cancer by low oxygen concentration||Comparing with common X rays|
|Effect exerted upon cancer by resistance to radiation||Comparing with common X rays|
|Number of times involving radiation||Comparing with common X rays, the number of times involving radiation are reduced|
Heavy particle radiation therapy
|Dosage concentration||More superior than proton radiation in terms of dosage concentration|
|Cell-killing effect||Approximately 3 times that of proton radiation|
|Effect exerted upon cancer by low oxygen concentration||More effective than common X rays|
|Effect exerted upon cancer by resistance to radiation||More effective than common X rays|
|Number of times involving radiation||Comparing with proton radiation, the number of times involving radiation are reduced|