The main recommended molecular mechanism by which LDRT treats pneumonia is the induction of anti-inflammatory effects [6] . Thus, the cost and benefit ratio for inhibition of inflammation at COVID-19 patients should be evaluated. Critically ill patients would be the first target for any possible clinical trials. Inflammatory cytokine storm affects a substantial number of these patients [7] . The LDRT is currently used for the decrease of limited inflammations in particular diseases like osteoarthritis and not a cytokine storm [8] . Thus, the anti-inflammatory effect of LDRT may not be very effective in controlling this storm in COVID-19. On the other hand, the most important concern about utilizing anti-inflammatory medications for controlling systemic inflammation is the suppression of immune response against infectious agents [9] . So, LDRT anti-inflammatory effects may disrupt immune system fighting against COVID-19 virus and delay virus elimination. Also, the window time of antiinflammatory treatment is very important. According to reports, fatal COVID-19 cases are usually fast progressive and deteriorate under two weeks after onset. Therefore, prompt initiation of the anti-inflammatory therapy at this extremely short golden window time is determinative in the treatment outcome [10] .
There is limited knowledge about the interaction of LDRT and viruses. Some studies have reported the significant increase of uptake, activation, transcription and spread of some viruses after radiation therapy [11] [12] [13] [14] . Therefore, maybe it's better not to use the lungs as the target organ for radiation therapy due to high virus concentration. It should be mentioned that LDRT anti-inflammatory effects aren't limited to the irradiated site and LDRT exhibits systemic effects [5, 6] . Therefore, maybe it's not necessary to just irradiate the lungs and total body LDRT may exhibit more efficacy.
Overall, it is necessary to completely investigate the LDRT effect on the COVID-19 virus and its cytokine storm in preclinical experiments to balance the risk and benefit ratio before designing further clinical trials. Also, inserting the LDRT anti-inflammatory effects at the right window time for each individual patient is determinative to reach the most favorable outcomes.