Use of colloids of chromic [32P] phosphate in treatment of solid tumors.
In order to evaluate the effectiveness of an intratumorally single dose of chromic [32P] phosphate for the treatment of solid tumors, studies of bioelimination, biodistribution, and therapeutic action were carried out. Only for comparative purposes were similar studies undertaken using a solution of sodium [32P] orthophosphate-gelatin. Results show that when sodium [32P] orthophosphate-gelatin was intratumorally injected, the percentage of total elimination, after 32 days of treatment, was equal to 85.90 +/- 8.70%, with a higher percentage in urine (64.50 +/- 13.70%) than in feces (21.40 +/- 4.50%). In biodistribution studies, the greater percentage was found in bone (15.54 +/- 2.21%), whereas only 2.51 +/- 0.39% remained in the tumor. When chromic [32P] phosphate was intratumorally injected, we found that the total elimination was equal to 51.70 +/- 6.90%, with a higher amount in feces (32.70 +/- 4.80%) than in urine (19.00 +/- 3.60%). Biodistribution studies demonstrated that 28.93 +/- 1.30% was still in the tumor and 19.01 +/- 1.30% of the injected activity was found in the liver. On the other hand, when therapeutic action was evaluated, no tumoral regression was observed. These results demonstrate that the colloid of chromic [32P] phosphate cannot be used in the treatment of solid tumors as it mobilizes from the injection point, delivering a high dose to the entire organism.
Zubillaga
M B
MB
Radioisotope Laboratory, Facultad de Farmacia y Bioquímica, U.B.A., Buenos Aires, Argentina.
Boccio
J R
JR
Nicolini
J O
JO
Ughetti
R
R
Lanari
E
E
Caro
R A
RA
D000230:Adenocarcinoma / Q000378:metabolism / Q000532:radiotherapy*; D000818:Animals; D017608:Chromium Compounds; D003102:Colloids; D005260:Female; D008325:Mammary Neoplasms, Experimental / Q000378:metabolism / Q000532:radiotherapy*; D008657:Metabolic Clearance Rate; D010710:Phosphates / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D010761:Phosphorus Radioisotopes / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014018:Tissue Distribution
D017608:Chromium Compounds; D003102:Colloids; D010710:Phosphates; D010761:Phosphorus Radioisotopes; C509369:chromic phosphate; C018279:sodium phosphate