Regional radiochemotherapy using in situ hydrogel.
OBJECTIVE
To evaluate the feasibility of regional radiochemotherapy of mammary tumors using in situ hydrogel loaded with cisplatin (CDDP) and rhenium-188 ((188)Re).


METHODS
Sodium alginate (SA) and calcium chloride were used to create a hydrogel for delivery of CDDP and (188)Re. In vitro studies were performed to evaluate cytotoxic effects of (188)Re-hydrogel and sustained-release ability of the CDDP-hydrogel. Tumor-bearing rats were injected with (188)Re-hydrogel (0.5-1 mCi/rat), (188)Re-perrhenate (0.5-1 mCi/rat, intratumoral, I.T.), CDDP-hydrogel (3 mg/kg), and (188)Re-hydrogel loaded with CDDP (3 mg/kg body weight, 0.5-1 mCi/rat), respectively, and groups receiving (188)Re were imaged at 24 and 48 h postinjection. Tumor volume, body weight, imaging, and kidney function were assessed as required for each group.


RESULTS
Successful formation of the hydrogel was demonstrated by cytotoxic effects of (188)Re-hydrogel and slow release of CDDP-hydrogel in vitro. Tumor volume measurements showed significant delay in tumor growth in treated vs. control groups with minimal variation in normal kidney function for the CDDP-hydrogel group. Scintigraphic images indicated localization of (188)Re-hydrogel in the tumor site up to 48 h postinjection.


CONCLUSIONS
Our data demonstrate the feasibility of using hydrogel for delivery of chemotherapeutics and radiation locally. This technique may have applications involving other contrast modalities as well as treatment in cases where tumors are inoperable.
Azhdarinia
Ali
A
Division of Diagnostic Imaging, The University of Texas M. D. Anderson Cancer Center, Houston, Texas, USA. aazhdari@di.mdacc.tmc.edu
Yang
David J
DJ
Yu
Dong-Fang
DF
Mendez
Richard
R
Oh
Changsok
C
Kohanim
Saady
S
Bryant
Jerry
J
Kim
E Edmund
EE
D000818:Animals; D001918:Brachytherapy / Q000379:methods*; D002945:Cisplatin / Q000008:administration & dosage / Q000378:metabolism / Q000493:pharmacokinetics; D004195:Disease Models, Animal; D004337:Drug Carriers / Q000008:administration & dosage / Q000138:chemical synthesis / Q000493:pharmacokinetics; D004354:Drug Screening Assays, Antitumor / Q000379:methods; D020100:Hydrogels / Q000008:administration & dosage* / Q000138:chemical synthesis / Q000627:therapeutic use*; D008325:Mammary Neoplasms, Experimental / Q000188:drug therapy; D009368:Neoplasm Transplantation; D011877:Radionuclide Imaging / Q000379:methods; D011879:Radiotherapy Dosage; D051381:Rats; D012211:Rhenium / Q000008:administration & dosage / Q000493:pharmacokinetics; D013678:Technology, Pharmaceutical / Q000379:methods
D004337:Drug Carriers; D020100:Hydrogels; D012211:Rhenium; D002945:Cisplatin