Speakers at the World Science Festival event, "Salon: Genetics and Cancer," on Friday morning included Eric Lander, Mary-Claire King, Emily Senay, Siddhartha Mukherjee and Charles Sawyers.  The warm-up act was a video of brightly colored cells, ropes of DNA and other mystery blobs — gorgeous and ominous — floating to solemn, New-Agey music with lots of strings and poignant piano notes. Slides broke in bearing scary statistics — cancer kills more than half a million Americans a year, for example — and quotes from researchers: “Cancer is always genetic.” Cancer cells are “more perfect versions of ourselves.”  The panelists were Eric Lander, an expert in genome sequencing; Mary Claire King, the first scientist to identify genes that can cause breast cancer; Olufunmilayo Olopade, a medical oncologist and breast cancer researcher; and Siddhartha Mukherjee, an oncologist and researcher, and author of the Pulitzer prize-winning book "The Emperor of All Maladies: A Biography of Cancer." The moderator was Dr. Richard Besser, a physician who is chief health and medical editor for ABC News.  Dr. Besser wore a sharp suit and tie, Dr. Mukherjee had artfully tousled hair and close-fitting white pants over boots, and the other three went business casual. Dr. Lander and Dr. King tried to high-five each other, missed once and then connected.  One major theme that emerged from the 90-minute discussion was that although genetic research has already helped in the diagnosis, treatment and prevention of some cancers, it may be decades before the science produces new treatments that come anywhere near the dream of curing cancer or at least making it a chronic disease.  Why try to sequence cancer genomes? Dr. Besser asked.  Dr. Lander said that cancer was caused by mutations and that it was “nuts” to think the disease could ever be cured without understanding what had gone wrong genetically. But the first step was to sequence the normal human genome; then, cancer genomes could be tackled. Cracking the normal genome cost a few billion dollars, but since then, he said, the cost of sequencing had dropped to $10,000 or less per genome, and so it made sense to apply the technology to cancer. Samples are needed from many patients with each type of cancer, he said. Sequencing a cancer from one person will reveal many mutations, but not all of them will be involved with the disease.  But with samples from many patients, researchers can hunt for culprit genes that are mutated in, say, half the cases, or maybe even all of them.  “Let the cancer tell you what’s important,” Dr. Lander said.  Genetic information is already being put to use to help women from families with mutations that cause breast cancer. Researchers can offer them options, Dr. King said, though she acknowledged that the options are “not pretty,” because they require removing the ovaries or breasts to avoid the disease. But the surgery can prevent 10,000 cases of breast cancer a year in the United States, she said.  Genetic findings have also led to some very focused treatments for cancer: drugs like Herceptin, for women with a certain type of breast cancer, and Gleevec, which is used for some blood cancers and gastrointestinal stromal tumors with specific mutations.  But Dr. Lander cautioned that individual targeted treatments were not cures. He cited a drug that can make tumors “melt away” in patients with melanoma, a deadly type of skin cancer. But they melt away for only eight months, he said. Then, the tumors “come roaring back,” because the cancer develops a new mutation and becomes resistant to the drug. He said cancer treatment needed what he called the “Colin Powell approach” — overwhelming force, which will probably turn out to be a cocktail of targeted drugs like the combination of antiretrovirals that can now keep H.I.V. in check for most patients.  Dr. Mukherjee said that in “Let Me Down Easy,” a play by Anna Deavere Smith, a character observes that giving chemotherapy is like hitting a dog with a stick to get rid of fleas. Flea ointment would work better, he said — but you might need six types of ointment.  Dr. Olopade said that as a medical oncologist, she had to defend chemotherapy, because it has cured many childhood leukemias.  Why not try to sequence as many cancer genomes as possible in the next five years? Dr. Lander asked. But he warned that the information would not lead to new treatments right away. He said that could take decades, and he accused the news media of “overpromising” and misleading the public into expecting cures within a few years.
Experts at the World Science Festival mused on individualized therapies, global involvement in clinical trials and the potential of genetic research to find a cure. Hint: It could take a while.