The president of the National Urban League said yesterday his organization is "ready, willing and anxious to join forces" with the American Cancer Society "in a massive, targeted campaign aimed at increasing black awareness of the dangers of cancer."

Vernon E. Jordan Jr. went on to say, however, that the civil rights group "cannot treat cancer prevention campaigns in isolation. For we recognize that cancer incidence is a phenomenon closely related to lack of health care and to social and economic disadvantage in our society.

"It is for that reason that we link cancer prevention campaigns to the issues of occupational safety, to full employment, to an end to poverty, to better housing. and to establishment of a universal, comprehensive consumeroriented national health system," Jordan told those attending the cancer society's first annual National Conference on Meeting the Challenge of Cancer Among Black Americans, which began Thursday and ends today at the Capital Hilton Hotel here.

Black males, according to a recent study, have the nation's highest cancer rates, and black males in Washington have higher rates than blacks or whites in the 10 metropolitan areas with the highest percentages of blacks.

"There is an increasing incidence and mortality of cancer in blacks," ACS president and Howard University surgery department chairman LaSalle D. Leffall Jr. told those attending the meeting.

Dr. Harold P. Freeman, an ACS director at large and chief of surgery at New York's Harlem Hospital, said in an interview Thursday evening that he suspects that the apparent racial differences in cancer rates are really socioeconomic differences.

Because a higher proportion of blacks are poor -- and therefore may receive worse medical care, have nutritional problems and work in more physically taxing jobs -- blacks have higher cancer rates, Freeman theorized, stressing that the epidemiological work has yet to be done to explain the racial or class differences.

Leffall said he "can recall the time I went out into Southeast (Washington) to speak, and I was talking about breast self-examination and the pap smear.

"A mother told me, she said, 'Dr. Leffall, I don't have anything wrong with my breasts, and nothing is hurting me down here,' and she pointed to her lower abdomen, 'but I m worried whether I can pay the rent next week, whether I can buy some winter clothes for my children in this cold weather.'

"So, therefore, health has a low priority very often," said Leffall, "and many poor, black patients come in with an advanced stage of the disease."