Dr. Anderson then introduced Dr. Rosenberg to explain why he felt 
that the execution of this protocol would improve cancer 
immunotherapy . 
Dr. Rosenberg said he would present an overview of where this 
protocol would fit into an 11-year effort to develop new 
treatments for cancer patients. He noted last year 485,000 
Americans died of cancer, and one out of every 6 Americans now 
alive will die of cancer if no new treatment modalities are 
developed. The three treatment modalities currently in use are: 
surgery, radiation therapy, and chemotherapy. He noted about 
half of all cancers can be cured by appropriate application of 
these modalities, but with the high incidence of the disease, 
there are still approximately one-half million cancer deaths each 
year . 
Dr. Rosenberg said one new modality is biologic therapy or 
immunotherapy, i.e., utilizing the body's own immune defense 
mechanisms to treat cancer. The particular immunotherapy being 
investigated by Dr. Rosenberg is called adoptive or cellular 
immunotherapy whereby a patient's own immune lymphoid cells are 
taken out of the body and induced to recognize and destroy cancer 
cells and later reintroduced into the body as an immune reagent. 
Dr. Rosenberg defined "adoptive immunotherapy" as "the transfer 
to the tumor-bearing host of active immunologic reagents with 
anti-tumor reactivity that can mediate directly or indirectly 
anti-tumor effects." A limitation to adoptive immunotherapy is 
the inability to generate sufficient numbers of cells with 
appropriate anti-tumor reactivity for transfer to tumor-bearing 
patients. The TIL protocol represents the first method for 
isolating and employing lymphocytes that will react with specific 
tumor antigens. 
Dr. Rosenberg said early efforts in adoptive immunotherapy were 
derived from studies that showed that lymphokine-activated killer 
cells (LAK cells) with anti-tumor reactivity could be formed by 
incubating lymphocytes, in vitro , with interleukin-2 (IL-2) to 
generate cells capable of lysing fresh tumor cells and 
reintroducing them into the host. This method has been used to 
treat over 300 patients and has proven useful in regression of 
tumor growth in some cases of advanced cancer. Dr. Rosenberg 
emphasized that these experiments were conducted in patients with 
advanced metastatic cancer who had failed all other therapies 
available and who had been sent home to die. The same population 
will participate in the proposed TIL experiment. 
Dr. Rosenberg said two-thirds of patients did not respond to the 
LAK treatment. As part of a continuous effort to improve 
adoptive immunotherapy, it was observed that lymphoid cells 
infiltrating a growing tumor had unusual properties and a 
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