The Emperor of All Maladies. Siddhartha Mukherjee

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      Trial methodology was not the only powerful lesson that Zubrod, Frei, and Freireich learned from the antimicrobial world. “The analogy of drug resistance³²⁰ to antibiotics was given deep thought,” Freireich remembered. As Farber and Burchenal had discovered to their chagrin in Boston and New York, leukemia treated with a single drug would inevitably grow resistant to the drug, resulting in the flickering, transient responses followed by the devastating relapses.

      The situation was reminiscent of TB. Like cancer cells, mycobacteria—the germs that cause tuberculosis—also became resistant to antibiotics if the drugs were used singly. Bacteria that survived a single-drug regimen divided, mutated, and acquired drug resistance, thus making that original drug useless. To thwart this resistance, doctors treating TB had used a blitzkrieg of antibiotics—two or three used together like a dense pharmaceutical blanket meant to smother all cell division and stave off bacterial resistance, thus extinguishing the infection as definitively as possible.

      But could two or three drugs be tested simultaneously against cancer—or would the toxicities be so forbidding that they would instantly kill patients? As Freireich, Frei, and Zubrod studied the growing list of antileukemia drugs, the notion of combining drugs emerged with growing clarity: toxicities notwithstanding, annihilating leukemia might involve using a combination of two or more drugs.

      The first protocol was launched³²¹ to test different doses of Farber’s methotrexate combined with Burchenal’s 6-MP, the two most active antileukemia drugs. Three hospitals agreed to join: the NCI, Roswell Park, and the Children’s Hospital in Buffalo, New York. The aims of the trial were kept intentionally simple. One group would be treated with intensive methotrexate dosing, while the other group would be treated with milder and less intensive dosing. Eighty-four patients enrolled. On arrival day, parents of the children were handed white envelopes with the randomized assignment sealed inside.

      Despite the multiple centers and the many egos involved, the trial ran surprisingly smoothly. Toxicities multiplied; the two-drug regimen was barely tolerable. But the intensive group fared better, with longer and more durable responses. The regimen, though, was far from a cure: even the intensively treated children soon relapsed and died by the end of one year.

      Protocol I set an important precedent. Zubrod’s and Farber’s cherished model of a cancer cooperative group was finally in action. Dozens of doctors, nurses, and patients in three independent hospitals had yoked themselves to follow a single formula to treat a group of patients—and each one, suspending its own idiosyncrasies, had followed the instructions perfectly. “This work is one of the first comparative studies³²² in the chemotherapy of malignant neoplastic disease,” Frei noted. In a world of ad hoc, often desperate strategies, conformity had finally come to cancer.

      In the winter of 1957, the leukemia group launched yet another modification to the first experiment. This time, one group received a combined regimen, while the other two groups were given one drug each. And with the question even more starkly demarcated, the pattern of responses was even clearer. Given alone, either of the drugs performed poorly, with a response rate between 15 and 20 percent. But when methotrexate and 6-MP were administered together, the remission rate jumped to 45 percent.

      The next chemotherapy protocol, launched just two years later in 1959, ventured into even riskier territory. Patients were treated with two drugs to send them into complete remission. Then half the group received several months of additional drugs, while the other group was given a placebo. Once again, the pattern was consistent. The more aggressively treated group had longer and more durable responses.

      Trial by trial, the group crept forward, like a spring uncoiling to its end. In just six pivotal years, the leukemia study group had slowly worked itself to giving patients not one or two, but four chemotherapy drugs, often in succession. By the winter of 1962, the compass of leukemia medicine pointed unfailingly in one direction. If two drugs were better than one, and if three better than two, then what if four antileukemia drugs could be given together—in combination, as with TB?

      Both Frei and Freireich sensed that this was the inevitable culmination of the NCI’s trials. But even if they knew it subconsciously, they tiptoed around the notion for months. “The resistance would be fierce,”³²³ Freireich knew. The leukemia ward was already being called a “butcher shop”³²⁴ by others at the NCI. “The idea of treating children with three or four highly cytotoxic drugs was considered cruel and insane,” Freireich said. “Even Zubrod could not convince the consortium to try it. No one wanted to turn the NCI into a National Institute of Butchery.”

       An Early Victory

      . . . But I do subscribe to the view³²⁵ that words have very powerful texts and subtexts. “War” has truly a unique status, “war” has a very special meaning. It means putting young men and women in situations where they might get killed or grievously wounded. It’s inappropriate to retain that metaphor for a scholarly activity in these times of actual war. The NIH is a community of scholars focused on generating knowledge to improve the public health. That’s a great activity. That’s not a war.

      —Samuel Broder, NCI director

      In the midst of this nervy deliberation about the use of four-drug combination therapy, Frei and Freireich received an enormously exciting piece of news. Just a few doors down from Freireich’s office at the NCI, two researchers, Min Chiu Li³²⁶ and Roy Hertz, had been experimenting with choriocarcinoma, a cancer of the placenta. Even rarer than leukemia, choriocarcinoma often grows out of the placental tissue surrounding an abnormal pregnancy, then metastasizes rapidly and fatally into the lung and the brain. When it occurs, choriocarcinoma is thus a double tragedy: an abnormal pregnancy compounded by a lethal malignancy, birth tipped into death.

      If cancer chemotherapists were generally considered outsiders by the medical community in the 1950s, then Min Chiu Li was an outsider even among outsiders. He had come to the United States from Mukden University in China, then spent a brief stint at the Memorial Hospital in New York. In a scramble to dodge the draft during the Korean War, he had finagled a two-year position in Hertz’s service as an assistant obstetrician. He was interested in research (or at least feigned interest), but Li was considered an intellectual fugitive, unable to commit to any one question or plan. His current plan was to lie low in Bethesda until the war blew over.

      But what had started off as a decoy fellowship for Li turned, within a single evening in August 1956, into a full-time obsession. On call late one evening, he tried to medically stabilize a woman with metastatic choriocarcinoma. The tumor was in its advanced stages and bled so profusely that the patient died in front of Li’s eyes in three hours. Li had heard of Farber’s antifolates. Almost instinctually, he had made a link between the rapidly dividing leukemia cells in the bone marrow СКАЧАТЬ