between 1982 and 1987 , 40 patients with esophageal tumors ( 19 adenocarcinomas , 19 squamous carcinomas , and two melanomas ) in whom conventional treatments were unsuccessful were treated with photodynamic therapy ( pdt ) after injection with either hematoporphyrin derivative or dihematoporphyrin ether .
C0121300
hematoporphyrin derivative
C0058031
dihematoporphyrin ether