A team of American and Egyptian doctors removed the deposed Iranian shah's spleen last night in what they described as a successful operation on the homeless former monarch.

"He was then placed under intensive medical care," added a bulletin early this morning from Military Hospital in the Cairo suburb of Maadi on the banks of the Nile.

The shah, 60, checked into the hospital at President Anwar Sadat's invitation last Monday after fleeing Panama, his residence since Dec. 15, in a dispute between his American doctors and Panamanian authorities about the conditions for the operation on the spleen, which was believed to be cancerous. c

The two-sentence announcement issued by the shad Mohammad Reza Pahlavi's doctors said nothing about his condition following the operation. Egyptian and Western experts here have said the spleenectomy required by the shah is a relatively routine operation, but that in his frail condition any surgery is dangerous.

In that light, the next few days were expected to be crucial in the shah's battle to stay alive despite the cancer that already has affected his lymphatic system. This is particularly true, they said, because although the Military Hospital enjoys a high reputation here, Egyptian medicine in general is considered lax in post-operative care.

The medical team that operated on the shah was led by Dr. Michael DeBakey of Houston, Tex., and included several French doctors and American surgeon, Dr. Benjamin Keane. DeBakey flew to Cairo Wednesday on a chartered jet that also transported cartons of blood and reportedly a sophisticated machine to help increase the platelet count in the shah's blood.

Since he arrived Monday after an overnight flight from Panama, the shah has been reported to be suffering from a slight fever and a significant low blood platelet count. The operation could be performed only when he overcame the fever and the count was raised to a minimum level, doctors said.

At the same time, Egyptian doctors who examined the shah said the removal of his spleen was relatively urgent because of the advanced state of his cancer. The terse medical bulletin that described the operation last night said nothing about whether any additional cancer was discovered during the surgery.

"When the good health condition of the former shah permitted, Dr. Michael DeBakey and a team of Egyptian and foreign doctors performed an operation and removed his spleen," the bulletin said. "It was successfully performed. He was then placed under intensive medical care."

[The Los Angeles Times reported that the doctors took samples in the course of the surgery to determine whether the tissue was malignant.]

The shah had a mild form of lymphoma, or lymph gland disease, for six yers. Last fall, he was found to have a serious form of lymph gland cancer. Recently doctors believed that his enlarged spleen probably signaled a spread of that cancer.

Given this history, the pathologists who examined the shah's spleen after surgery generally would have started to look for cancer cells. If present, the doctors then have to determine how grave the cancer was.

Given the nature of the shah's cancer, his surgeons would also have examined his entire abdominal cavity. Any cancer found there -- and this is common when the spleen is involved -- would mean a highly grave diagnosis and a poor outlook for the former shah.

The spleen serves as a filter for the blood, but it is not essential for life except in childhood, when it helps insure immunity.

The shah had his gall bladder removed and received radiation treatment for cancer during hospitalization last November and December in New York. It was his admittance to the United States for that round of medical care that led Iranian militants to take over the U.S. Embassy in Tehran, imprisoning an estimated 50 American hostages inside the building.

Sadat has been the object of severe criticism from Iran's Islamic revolutionary authorities for welcoming the shah, who is shunned by the rest of the world and is wanted in his own country on charges that he plundered the national treasury and ordered the torture of thousands of Iranian dissidents.

But the Egyptian leader has replied testily that the Iranians and their backers can shout "until the end of the world" without influencing him to go back on his gesture. True Islamic principles of compassion and hospitality demand that Egypt offer aslyum to the shah, Sadat declared, and the former "King of Kings" is welcome to live permanently in Egypt.

Sadat is also said to feel a debt of personal gratitude to the shah, who diverted shipments of Iranian oil headed for Europe and dispatched them to Egypt to avert a crisis here shortly after the 1973 Middle East war. In addition, Sadat has said the shah extended large credits to Egypt -- reported to have reached billions of dollars -- to help Sadat's government through the difficult days after the war.

The shah's wife, Farah, has been staying with him in his suite of rooms on the third floor of Maadi Military Hospital. Other members of the family -- including the shah's sister princess Shams, her husband, most of the shah's children and the shah's two pet dogs -- are living in Tahra Palace, a former residence of Egypt's Queen Farida in the suburb of Heliopolis, which Sadat made available to them.

The hospital is surrounded by Egyptian Army security forces carrying submachine guns and backed by a pair of armored personnel carriers. Sadat is reported to have ordered Vice President Husni Mubarak to take personal charge of the shah's security.

Egyptian authorities are said to fear an assassination attempt by Iranians who have threatened to kill the shah or by Palestinian radicals sympathetic to the fundamentalist Islamic revolution in Iran that drove the shah from his Peacock Throne in January 1979.

Egypt was the shah's first stop on his flight from Iran. He spent six days at Aswan in upper Egypt before continuing on what was to become an uncertain and humilitating search for a place to take up residence.

From Egypt, he went to Morocco to stay with his fellow Islamic monarch, King Hassan II. After several weeks, however, he was put on notice that he had overstayed his welcome. From there, the shah traveled to the Bahamas and then to Mexico, where he stayed until entering the United States for medical care. After Mexico refused to renew his visa, he found a refuge on a tropical island off Panama with help of the United States.

Through his search, Sadat repeated his offer of permanent asylum in Egypt. It was refused at the time, because of reported concern in the shah's entourage that he could not get proper medical care here and the reluctance of the United States to see Sadat shoulder the responsibility of his care in a gesture certain to provoke his Arab opponents and stir criticism at home.

The United States reportedly expressed concern to the Egyptian government again this week that the shah's presence here could complicate efforts to free the American hostages in Tehran and aggravate Sadat's relations with other Arab nations already opposed to his peace treaty with Israel.

Egypt's leftist parties have expressed outrage at the shah's arrival and a small band of Moslem fundamentalist students demonstrated Wednesday at Cairo University against the Egyptian leader's gesture.

Most Egyptians, however, appear unconcerned about the shah's presence in their country. In casual conversation, many agree with Sadat's contention that hospitality to a sick man is part of the Islamic heritage that is a strong part of Egyptian life.