WASHINGTON - New York Democratic Rep. Eric Massa, facing a harassment complaint by a male staffer, said Friday that he is stepping down from his seat with "a profound sense of failure."

"I am guilty," Massa said in an interview with a Corning, N.Y., newspaper columnist.

Later in the day, Massa released a statement saying that after discovering he had a recurrence of cancer, he learned he was the subject of an ethics complaint by a male staffer who felt "uncomfortable" during an exchange with Massa. The exchange reportedly had sexual overtones.

"I will resign my position," Massa said in the statement.

"There is no doubt in my mind that I did in fact, use language in the privacy of my own home and in my inner office that, after 24 years in the Navy, might make a chief petty officer feel uncomfortable," Massa added. "In fact, there is no doubt that this ethics issue is my fault and mine alone."

Earlier Friday, a visibly upset Massa said he didn't want to put his family through an ethics committee investigation.

"It would tear us apart," Massa said, according to Joe Dunning, a columnist for The Leader newspaper. "It's not that I can fight or beat these allegations, I'm guilty."

The resignation takes effect Monday.

The allegations pushed a relatively unknown freshman into the national spotlight in a way no lawmaker would wish.

A resident of Corning, N.Y., Massa, 50, is a 24-year retired Navy commander who served during Operation Desert Storm and later was special assistant to Gen. Wesley Clark during the conflict in Bosnia. A terminal cancer diagnosis in 1996 forced Massa and his family back to the U.S. for treatment. He spent his last year in the Navy as a cancer outreach advocate and later took a professional staff job with the House Armed Services Committee.

Massa defeated Republican Rep. Randy Kuhl in 2008 in a district that voted for GOP presidential candidate John McCain. The largely agricultural district has been dominated by Republicans since the party's founding in 1854. Massa serves on the House agriculture, armed services and homeland security committees.

His departure is good news for House Speaker Nancy Pelosi's effort to advance a troubled health care overhaul. Massa had voted against it. His departure reduces the majority she needs for passage to 216.

Massa's acknowledgment of inappropriate behavior comes as the House's majority Democrats struggle with ethics matters among their own ranks despite promising to clean up Congress when they came to power.

The New York delegation has been especially hard-hit by ethics matters. Rep. Charlie Rangel, a 20-term House veteran and the most influential member of the delegation, surrendered the chairmanship of the tax-writing Ways and Means Committee this week after the ethics committee found that the Harlem Democrat had broken House rules on accepting gifts.

And New York Gov. David Paterson dropped his re-election bid because of evidence he may have pressed the girlfriend of his closest top aide to drop charges of domestic violence against that aide. He's losing staff amid calls for him to quit. Paterson said Friday he has no plans to resign and intends to clear his name.

Massa at first dismissed the allegations against him. The ethics committee issued a statement Thursday saying it is "investigating and gathering additional information concerning matters related to allegations involving" Massa.