At first it sounded like a macabre coincidence. Within three days in March 1983, two California cousins learned from their doctors that they had non- Hodgkin’s lymphoma, a cancer of the immune system. One month earlier, a sister-in-law of one of them, living in Washington, had received the same diagnosis. The family was stunned. What could be causing their unbelievable misfortune? In Georgia, a few months later, when the married daughter of one of the victims discovered that she too had the malignancy, the family could not avoid what had earlier seemed an illogical, incredible conclusion: four of them had “caught” cancer from a 63-year-old South African aunt who in 1982 had crisscrossed the U.S., visiting her late husband’s relatives. Family members, who have requested anonymity, recalled that the aunt had suffered from a severe sore throat during her tour and wondered if she had somehow passed along an infection that caused cancer. Poring over medical books in local libraries, they found no reference to a viral cause of non- Hodgkin’s lymphoma. Instead, they came upon another cancer of immune-system cells, Burkitt’s lymphoma, which afflicts black African children and is strongly associated with infection by the Epstein-Barr virus. Even though the stricken family is white, says the Georgia victim, “it was the only viral- caused cancer that we could find. Because of that and because of where our visitor came from, we started making the connection.” Confronting their doctors, the victims asked if they might have Burkitt’s lymphoma, caught from their visiting aunt. A typical reaction, says the Georgian, was ” ‘Don’t you ever say anything like that. If you came into my office and said that cancer is contagious, it would empty out.’ ” In desperation, a family member called Dr. Seymour Grufferman, a cancer epidemiologist at Duke University Medical Center, explained the contagion idea and sent him biopsy slides of the victims’ tumors. Grufferman too was skeptical — until examination of the slides showed that one patient indeed had Burkitt’s lymphoma. With Dr. Joseph Pagano, a cancer virologist at the University of North Carolina, Chapel Hill, he promptly launched an investigation. Soon, Pagano recalls, “we realized that a virus was a more likely explanation than any other.” The two researchers found that the aunt had become ill just before she left Africa and that blood samples from four of the twelve Americans she visited showed signs of recent Epstein-Barr virus infection. Genetic causes were ruled out because not all the victims were blood relations. Says Grufferman: “This is one of the best-documented cancer clusters worldwide, but it’s difficult to investigate.” One of the difficulties is the mixed signal provided by the viral evidence. Signs of Epstein-Barr infection were found in one family member with non-Hodgkin’s lymphoma but were absent in two of the other cancer victims . Was some other virus, still undiscovered, responsible for the familial outbreak?
