INFUSIONAL BRACHYTHERAPY IN THE TREATMENT OF NONRESECTABLE PANCREATIC-CANCER - A NEW RADIATION MODALITY (PRELIMINARY-REPORT OF THE PHASE-I STUDY)

Selective tumor targeting with infused radioimmunoconjugates has been limited in tumor dose deposition. Molecular size, interstitial tumor p ressure and circulating radioimmunoconjugate-related toxicity has limi ted selective high tumor dose radiation by infusional techniques. Due to a variety of laboratory studies, a new method has been devised whic h deposits as high as 94% of the infused dose in pancreatic cancer. Un der CT guidance, direct tumor infusion was carried out with 2.5 millio n particles of macroaggregated albumin (MAA), followed by P-32 chromic phosphate, in a Phase I study in conjunction with external radiation and 5-FU. (32)p infusion produced tumor doses from 23,000 to 500,000 c Gy. In conjunction with external radiation there has not been signific ant toxicity. The P-32 infusion was administered on an out-patient bas is and has resulted in a median survival greater than eight months wit hout toxicity. A new method of direct infusional brachytherapy of panc reatic cancer can be achieved by using MAA + chromic phosphate P-32, a dding significant radiation selectively to the tumor. Completion of th e Phase I trial and a national Phase II trial is anticipated.