A low-tech approach to stimulating the immune systemappears to work well against bladder cancers, according tofindings by scientists from the Southwest Oncology Group.
Of 285 patients with various types of recurrent bladdercancer, the probability of being cancer-free after five yearswas 37 percent after immunotherapy with bacille Calmette-Guerin (BCG), a weakened cow bacterium developed in the1920s as a vaccine against tuberculosis.
By comparison, the probability was 17 percent after aconventional treatment with the drug doxorubicin.
Of those who received BCG, 70 percent showed a completeresponse (absence of any diagnostic signs of cancer), comparedwith 34 percent who got doxorubicin.
Both agents were administered directly into the bladder.
Biotechnology approaches to the same end -- recruiting aperson's own immune system with cytokines to fight amalignancy -- have not shown the kind of remission ratesobtained with BCG.
"With the possible exception of alpha interferon in hairy cellleukemia, I think we've blown out every other biologicaltreatment for cancer," said Dr. Donald Lamm, a West VirginiaUniversity Medical Center urologist on the team that reportedthe bladder cancer results Thursday in the New England Journalof Medicine.
Lamm told BioWorld that results previously presented at ameeting show that BCG can achieve an 82 percent completeresponse rate in bladder carcinoma in situ, which comparesfavorably with a 90 percent rate seen with alpha interferon inhairy cell leukemia.
Bladder cancers affect 500,000 people in the United States,Lamm said. BCG has been approved by the Food and DrugAdministration for treatment of carcinoma in situ. Companieswill be seeking approval to market the bacteria for otherbladder cancers besides carcinoma in situ, which accounts for10 percent to 15 percent of the cases, he said.
Connaught Laboratories Inc. of Swiftwater, Pa., supplied theBCG used in the study. Organon Teknika Corp. of Durham, N.C.,distributes its Tice strain of BCG through Organon Inc. of WestOrange, N.J. Both are units of Akzo Pharma International BV ofthe Netherlands.
-- Roberta Friedman, Ph.D. Special to BioWorld
(c) 1997 American Health Consultants. All rights reserved.