High incidence of migration inhibition reactivity to lung tumor-associated antigen by normal donors in close contact with lung cancer patients or materials

A high incidence of indirect leukocyte migration inhibition reactivity of normal donors to a 3-M KCl extract from a fresh pleural effusion of a patient with a lung adenocarcinoma (designated 7661) was observed. When these normal donors were classified according to contact with lung cancer patients or materials, 22 of 32 (72%) normal donors in contact with lung cancer patients or materials were reactive with the 7661 extract as compared to only 3 of 76 (4%) who had no contact. Of normal donors involved in the direct care of lung cancer patients, 14 of 20 (70%) were positive, whereas only 2 of 10 (20%) hospital personnel who worked with noncancer patients were reactive. Among laboratory personnel who handled blood and tissue specimens from lung cancer patients, 8 of 11 (73%) were positive with the 7661 extract, whereas none of 5 laboratory workers who worked with cancer materials unrelated to lung cancer were positive. Also, none of 13 personnel working in laboratories adjacent to those where lung cancer tests were performed were reactive with 7661. None of the 16 blood bank donors and none of 11 secretarial and clerical staff who worked in biochemical laboratories were positive. Reactivity was no correlated with a smoking history. Thus development of reactivity appeared to require direct contact with lung cancer patients or materials. The results suggested a horizontal transmission of reactivity against an antigen associated with lung cancer.