Stopping Cancer in Its Tracks

Stealthy as a pirate slipping from a cove, the cancer cell severs the moorings that attach it to surrounding tissue. Slowly it extends one, two, three fingerlike probes and begins to creep. Then it detects the pulsating presence of a nearby capillary and darts between the cells that compose the blood- vessel wall. It dives into the red river that courses through lung and liver, breast and brain. An hour or so later, it surfaces on some tranquil shore, settles down and -- at the expense of its hapless neighbors -- begins to prosper.

Gradually the cancer cell invades the turf occupied by its normal counterparts, killing all those in its path. It tricks nearby cells into forming food-bearing blood vessels, then compels them to churn out growth- spurring chemicals. To shield itself from patrolling immune cells, the cancer cell sprouts spiny armor like a sea urchin's. To expel the agents physicians send to kill it, the cancer cell deploys along its membrane a battery of tiny pumps. Is there a way to fight such a foe?

Until now, medicine has tried to overwhelm the cancer cell with brute force, slicing it out with surgery, zapping it with radiation or poisoning it with chemotherapy. All too often, however, a few cells manage to survive the onslaught and germinate, sometimes years later, into tumors that are impervious to treatment. The ability of the cancer cell to outmaneuver its attackers has long been reflected in mortality statistics. Despite gains made against cancers such as childhood leukemia and Hodgkin's lymphoma, the overall death rate remains dismally high. This year more than half a million Americans will succumb to cancer, making it the nation's second leading killer after cardiovascular disease.

Yet despite the continuing casualties, there is reason to believe the war against cancer has reached a turning point. During the past two decades, a series of stunning discoveries has pried open the black box that governs the behavior of the cancer cell and revealed its innermost secrets. Now the insights gleaned from basic research are being translated into novel approaches to cancer therapy. It still looks difficult to eradicate malignant cells, but scientists are exploring ways to tame them, to make them behave and thus greatly prolong the lives of people with the disease. The new therapies carry the promise of being not only more effective than the current slash-and- burn strategy but also much gentler to the patients who must endure the treatment. Exclaims Dr. Dennis Slamon, a UCLA cancer specialist: "This is the most exciting time imaginable!"