BALTIMORE, SEPT. 5 -- A federal judge today threw out as groundless the $3.5 million claim of the widow of Sen. John P. East (R-N.C.) that U.S. Navy doctors were negligent in treating the senator before his suicide in 1986.

U.S. District Judge Walter E. Black Jr. held that the delayed diagnosis of East's hard-to-detect thyroid ailment did not violate "applicable standards of care" and that the doctors cannot be held responsible for East's death.

"The court finds that Sen. East's presentation {of symptoms} between April 1983 and April 1985 would not have led a reasonable internist under the circumstances . . . to test for" the thyroid condition," Black wrote in a 56-page opinion.

The ruling was applauded by government lawyers who defended the Navy doctors, including former U.S. Capitol attending physician Freeman H. Cary.

"I am delighted," said Maryland U.S. Attorney Breckinridge L. Willcox, adding that Black "came to the correct decision and proper analysis" in a tough case.

He described as "tragic" the decision by East's widow, Priscilla, to bring "this ill-advised and meritless lawsuit."

Despite today's vindication of Cary, Willcox said, the suit "had the predictable effect of ruining the reputation of a very eminent and distinguished physician" who retired early because of the suit.

Cary could not be reached for comment.

Priscilla East's attorney, Terri A. Steinhaus, said Black's decision was "unsupported by the evidence."

She said Black seemed to suggest that "physicians need not look beneath the surface of a patient's complaints or to investigate known laboratory abnormalities."

Steinhaus said Priscilla East had no comment at this time, adding that no decision has been made on whether to appeal.

The case has been watched closely by doctors and medical administrators, especially in the Navy, which is responsible for health care at Bethesda Naval Hospital and the Office of the Attending Physician at the Capitol.

John East, a political science professor and conservative elected to the Senate in 1980, committed suicide on June 29, 1986, by filling the garage at his home in Greenville, N.C., with carbon monoxide. He left a note blaming Navy doctors "who ruined my health." He was 55.

Priscilla East sued the government in 1987, saying that doctors had ignored early symptoms of hypothyroidism, a condition in which the thyroid fails to produce hormones to maintain the body's proper metabolism.

She contended that the symptoms -- fatigue, depression and abnormal levels of cholesterol and liver enzymes -- were apparent in 1983 and 1984 but that doctors did nothing until April 1985. At that time East was rushed to Bethesda Naval Hospital in an advanced psychotic state of hypothyroidism.

He became delusional and attempted suicide, family lawyers claimed, before doctors discovered the thyroid condition and stabilized it with synthetic hormones.

Even though the condition was corrected, family lawyers argued, East's thyroid-induced depression became "autonomous," triggering an "irresistible impulse" to commit suicide.

Assistant U.S. Attorneys Susan M. Ringler and Ira L. Oring countered that many of East's early symptoms were not indicative of hypothyroidism and that doctors could not be expected to diagnose it. Also, they said, East's depression was caused by external influences, including finding his Senate duties unchallenging.

Judge Black, citing testimony of government doctors and rejecting testimony of East's doctors during a non-jury trial earlier this year, said today: "The court finds that Sen. East did not present with the classic signs and symptoms of hypothyroidism and that the few signs and symptoms that did exist were too non-specific to require a thyroid function test."

He added, "While in hindsight it is clear that Sen. East was hypothyroid for a period of time prior to April 1985 . . . and while it is truly unfortunate that Sen. East's hypothyroidism progressed to such an extreme stage," government doctors nevertheless acted properly.