Members of four American households developed cancers of the lymph system after visits from a 65-year-old South African woman in what may be a "rare coincidence," but the possibility of their catching cancer from the visitor must be investigated, researchers said Friday.
The "interesting and unusual occurrence . . . makes it necessary to investigate whether a transmissible agent is responsible, in particular, a virus," they said.
Most Immune to Virus
Their statement, which said that the suspected virus is common but that most adults are immune to it, was issued by Dr. Dani Bolognesi, deputy director of the Duke University Comprehensive Cancer Center in Durham, N.C., Dr. Seymour Grufferman, an epidemiologist and pediatrics professor at the center, and Dr. Joseph Pagano, director of the Lineberger Cancer Research Center at the University of North Carolina at Chapel Hill.
Researchers at the university and Duke have been investigating a claim, from a member of the public, that four adults developed lymphoma after a 1982 visit by the South African. Grufferman said Thursday that he has found evidence of a transmittable agent.
"Our results have been confirmed in numerous other laboratories," he said.
The visitor spent time in four households in Georgia, California and Washington. Within 11 months, one adult in each home developed cancer of the lymph system.
Grufferman said that a possible fifth case is unconfirmed. "Even though the numbers are small, when you think of 4 out of 11, or 5 out of 12, this is a frightening kind of thing," he said.
During the visit, the woman showed symptoms of infectious mononucleosis, from which she recovered at home, Grufferman said. That disease and a type of lymphoma, Burkitt's lymphoma, which is rare in the United States but more common in Africa, have been associated with the Epstein-Barr virus.
The Friday statement said the Epstein-Barr virus is under investigation. It is very common, the statement said, but "over 80% of American adults are already immune to it."
One cancer victim has died, two appear to have been cured by chemotherapy and one still shows symptoms, Grufferman said.