Doctors who removed the hugely bloated spleen from the cancer-stricken deposed shah of Iran declared today that he is recovering satisfactorily from a "critical" 80-minute operation and that he will be able to resume a normal life, including tennis.

But the four doctors who performed the surgery last night caution that only after they know the results of laboratory tests on specimens of the shah's liver, spleen and bone marrow will they be able to say with certainty whether the cancer previously found in lymph nodes in his neck has spread to other parts of the body.

Their comments at a news conference in Cairo's Military Hospital, where the surgery took place, thus delayed perhaps for several days, any informed prediction of how long the ailing Iranian leader can be expected to live in his new Egyptian refuge. Mohammed Reza Pahlavi Anwar Sadat despite outcries from Iran's new rulers and their supporters in Egypt and the Arab world.

In a way, U.S. efforts to free American hostages in Tehran are tied to the shah's health. On the one hand, his death would overtake the Iranian demand that he return to face trial as a condition for the hostages' departure. dOn the other, the sight of the shah enjoying a relatively normal life in Egypt could provoke Iran's militant students who have been holding the Americans since Nov. 4.

Dr. Michael DeBakey of Houston, who led the surgical team, said the shah's spleen had enlarged to 10 times its normal dimension -- swelling from the size of a man's fist to that of a football and to a weight of 4.4 pounds. The spleen ordinarily play a blood-cleansing function unneccessary after childhood.

"The condition was serious and the operation was a critical one," DeBakey said, adding that the shah risked death if it had been delayed any longer.

Working with DeBakey were two eminent Egyptian surgeons, Drs. Fouad Nur and Mohammed Kamel, and BeBakey's associate at Baylor University, Dr. Gerald Lawrie. Also involved were Drs. Georges Flandrin of St. Louis Hospital in Paris, who has been treating the shah's mild lymph gland disease since 1974, and Hibbard Williams, who helped treat the cancerous lymph nodes in the shah's neck last November in New York.

The shah's wife Farah, their children and the shah's sister Princess Shams watched the operation from another room in the Nile-side hospital on closed-circuit television, DeBakey said. Farah visited her husband soon after the operation, when he became conscious.

The former march was "resting comfortably" today and his condition was "very satisfactory," leading to the expectation that he can leave his hospital suite for another residence in about 10 days, the doctor added.

Dr. William made it clear that a long-term prognosis for the shah depends on the outcome of testing the specimen's removed during last night's operation. He declined to confirm declarations by several Egyptian doctors that the spleen's swelling was definetly due to cancer. "In the United States we have a saying, hope for the best and expect the worst," said Williams.

[Medical sources in the United States suggests that if the cancer were widespread it might well have been apparent during the operation.]

"These tests that are currently being done, since the operation, are very important," Williams said. "They will help decide whether it has spread. But at the present time, we have no evidence and we have not had any positive evidence of spread."

DeBakey went out of his way to laud Sadat of his warm welcome of the shah and his cooperation with American doctors called in to perform the operation. A dispute with Panamanian authorities and doctors over who would have authority over the spleenectomy was a major factor in the shah's abrupt departure last Sunday from Panama, where he had resided since leaving New York Dec. 15.

"I find conditions here more conductive to his well being," DeBakey said, causing smiles to break out on the faces of his Egyptian colleagues. Later he added about the Panamanian imbroglio: "A problem arose about facilities in the hospitals and the personnel and authority for the operation. This cause not only a problem for his treatment, but also in a sense increased his anxiety and concerns."

In contrast, he continued, the warmth exhibited by Sadat and the hospital staff here helped boost the shah's morale, contributing to his readiness for surgery. The Egyptian leader personally welcomed the shah on arrival and has since vistited him at the hospital twice, emphasizing that the shah is welcome here for permanent asylum.

"I think this reflects the truly great humanitarian character of the Egyptian people that is symbolized by their president, Anwar Sadat," DeBakey said. "I think it is really an example to the entire world."

Sadat's stand exposes him to several risks. The new rulers in Iran, who were seeking the shah's extradition from Panama, have expressed anger at the Egyptian leader and they or some of their supporters could try to mount assaults here or abroad against the shah or Egyptian officials.

In addition, the Arab world, already ranged against Sadat for his peace treaty with Israel, finds in his welcome of the shah another indication that he has deserted his brethren in favor of alliance with the United States. This comes at a critical juncture in Palestinian autonomy talks among Egypt, Israel and the United States.

Sadat's embrace of the shah also has stirred up some opposition within Egypt.Islamic fundamentalist students demonstrated Wednesday at Cairo University and Moslem extremists in the central Nile Valley town of Asiut reportedly mounted a violent anti-shah protest last night that prompted police to intervene with tear gas.

An opposition member of parliamen, Mumaz Nassar precipitated a debate today on the wisdom of Egypt's welcoming the shah with such open arms. The minister of state for foreign affairs, Fouad Butros, defended Sadat's policy, saying Egyptian missions abroad are getting enough protection to prevent any assault by revenge-seeking Iranians.

The U.S. decision to allow the shah to enter the United States for medical treatment last fall led to seizure of The U.S. Embassy in Tehran by militant Islamic students and their imprisonment of the American diplomats there.

With this and the autonomy negotiations in mind, the United States reportedly made known to Egypt last weekened its concern lest Sadat turn his hospitality into another problem for Egypt by making it an act of defiance toward Iran and its Arab backers. Sadat, nevertheless, has bitterly denounced the new Iranian leadership for its efforts to avenge the shah, saying Egypt's hospitality is an example of true Islam.

Robert Armao, spokesman for the shah, said the family's residence at the Government-owned Tahra Palace in a Cairo suburb, is only temporary. For the moment however, the shah's employes are not actively seeking a permanent Egyptian home for him, Armao said.