January 18, 1986

Doctors removed three ''very small polyps'' from President Reagan's colon today and said the specimens were ''clinically benign,'' the White House announced tonight. The White House, in a statement, said the growths would be tested for cancerous tissue. ''Final results of these tests will be released as soon as they are available,'' the White House said. The examination, which was scheduled some time ago as a routine follow-up to Mr. Reagan's surgery in July, also disclosed a papule, or small growth, on the President's face; tissue was taken for a biopsy to determine if it contained any malignant cells.

Justice Stephen G. Crane acknowledged on Thursday with unusually forceful language how extraordinary the case of Bernhard H. Goetz had become. He called it ''one of the most difficult of our generation,'' and said that when Mr. Goetz shot four young men on an IRT subway train a year ago, his action ''galvanized the world.'' Still, the heart of Justice Crane's opinion, a preview of the legal issues certain to emerge should Mr. Goetz ever be tried, concerned issues that are old indeed, though never satisfactorily resolved: When is the use of self-defense defensible? And through whose eyes - those of the crime victim or of a hypothetical ''reasonable man'' -must that determination be made? Judge's Argument In dismissing the charges of attempted murder and assault against Mr. Goetz, Justice Crane ruled, in essence, that it was the subjective perceptions of Mr. Goetz, the traumatized victim of a previous subway assault, that must determine his culpability in the case. The prosecution erred, he concluded, by telling the grand jurors to ask themselves how they would have reacted had they found themselves in Mr. Goetz's situation, instead of if they were Mr. Goetz himself.

A tank battle raged today between rival Lebanese at the approaches to the hometown of President Amin Gemayel as Lebanon slipped closer toward full-scale civil war. A Lebanese Army spokesman said Christian troops loyal to Mr. Gemayel used United States-supplied tanks and armored personnel carriers to drive back Syrian-backed Moslem and leftist militiamen using Soviet-built tanks. The spokesman said the Moslem and leftist forces had tried to advance on Bikfeiya, Mr. Gemayel's hometown in the mountains 12 miles northeast of central Beirut. Artillery Duels in Villages The spokesman said 21 attackers had been killed and more than 50 wounded. The army lost 11 dead, he said, and 26 soldiers were wounded.

A panel of the State Parole Board voted unanimously today against releasing a convicted murderer granted clemency by Governor Cuomo. Parole officials said the vote - the first time in a decade that the board had not released a prisoner granted clemency - had been based on ''the extensive prior criminal record'' of the inmate, Gary McGivern, and on ''the gravity'' of his crime. Next Hearing Delayed The three-member panel also voted that Mr. McGivern, who was convicted in the 1968 murder of a deputy sheriff, would not be eligible for parole again for two years, the maximum time it could have delayed his next hearing. In granting clemency, the first time he had done so in a murder case, Mr. Cuomo made Mr. McGivern eligible for parole immediately, instead of in 1992, subject to the approval of the Parole Board.

Previous Pentagon studies have paid too little attention to the fundamental problem of how to design computer programming that could manage a space-based antimissile system, a panel appointed by the Defense Department has concluded. In a report submitted last month but not yet distributed by the Pentagon, the panel asserted that developing an effective battle management system, using reliable computer programs, is ''the paramount strategic defense problem.'' The panel recommended that the Pentagon reverse its usual pattern of planning ''to acquire the weapons first'' and then devising ''the supporting command, control and communications structure as an add-on.'' Key Issue in Debate The issue of the difficulty of developing reliable computer software to control a vast defensive system has been a key one raised in arguments over whether to pursue President Reagan's plan.