In 1966, hematoporphyrin derivative (HpD), the first-generation PSs, was reported to use in breast cancer treatment.120 After that, Kelly and Snell reported HpD in bladder cancer treatment in 1976.121 Until 1993, Photofrin (porfimer sodium), a purified component of HpD, was first approved for bladder cancer treatment in Canada.13 From then on, the curtain was raised for the application of PDT in cancer treatment. The gene discussed is HPD; the disease is urinary bladder carcinoma.