Faculty Bibliography

It was good news because tests showed that the cancer was limited, confined within the muscle of his bowel wall, and had showed no signs of spreading elsewhere in the bowel. ''The chances are excellent that this tumor will not occur again,'' said Dr. Steven Rosenberg of the National Cancer Institute, a member of the surgical team caring for the President. While Dr. Rosenberg said that in Mr. [Reagan]'s case ''there is a greater than 50 percent chance'' that he was completely cured, he did not identify the cancer as being Dukes B-1 or B-2. Other experts, however, have estimated the survival rate at about 80 percent for B-1 and in the range of 50 to 60 percent for B-2. Dr. Rosenberg recognized the controversy about such therapy. ''This is an area in which oncologists may have some differing opinions,'' Dr. Rosenberg said. London Doctor Devised System The prognosis Mr. Reagan's doctors gave was based on the Dukes staging, a system named for Dr. Cuthbert E. Dukes, a pathologist at St. Mark's Hospital in London, who reported his classification plan in 1932.

African sleeping sickness of humans is caused by two strains of trypanosomes that can only be distinguished by laboratory tests and that are distinguished primarily by epidemiologic factors. East African trypanosomiasis causes its damage in a few months, more swiftly than the West African form that can become chronic, taking years to develop. (A Central and South American form called Chagas' disease, which is spread by bedbugs and affects 10 million people, is caused by yet another strain of trypanosome.) Blood-sucking tsetse flies inoculate the parasite as they bite humans or animals. The first symptoms are nonspecific: a swollen area at the site of the bite, and then headache, mild fever, fatigue, swollen lymph nodes that sometimes become tender and a faint rash that fades in about a week. The liver and spleen may swell. Meanwhile, the parasites replicate in the body and eventually make their way to the central nervous system. As that invasion occurs, a victim's speech slows to a mumble, spontaneous conversation stops, a vacant stare develops, the gait shuffles, the hands and tongue tremble, apathy and indifference turn into somnolence, sometimes alternating with insomnia during the night, and then coma. A sleeping patient may be roused but, because of lack of interest, soon falls asleep again. DFMO's role in trypanosomiasis came about when researchers interested in enzymes and cell growth began a series of biochemical manipulations in the mid-1970's. They were also interested in polyamines, substances that exist in all living cells and that play important roles in processes required for rapid cellular growth and replication. A key enzyme in the production of polyamines is ornithine decarboxylase, or ODS, and DFMO irreversibly inhibits ODS. Dr. Cyrus J. Bacchi of Pace University said a key step occurred in about 1977 when he began collaborating on DFMO after meeting Dr. Peter P. McCann of Merrell Dow at a Gordon conference. That led to the discovery of a dramatic curative effect of DFMO in mice; the drug cured the mice infected with a virulent strain of trypanosome within a week. Since then, DFMO has had widespread use as a biological tool in research, and chemists have begun synthesizing other suicide inhibitors in hopes of finding cures for other diseases.

WASHINGTON - In removing a large polyp Saturday afternoon from President [Ronald Reagan]'s colon, Dr. Dale Oller and his team of surgeons did not know if it was malignant or benign, and so they acted according to prudent medical practice and proceeded as if the polyp was a cancer. Thus they removed not only the polyp but also about a two-foot-long piece of Reagan's bowel, which is tubular in shape. Then they sewed the two ends of the remaining bowel together, one from the ileum, or the last section of the small bowel, to the transverse, or second section, of the large bowel. The missing section of bowel is not expected to interfere with Reagan's bowel function, Oller, a Navy captain, said after the operation. Oller described it as ``a no-touch'' cancer procedure, one in which the surgeons avoid touching the polyp for fear of spreading cancer cells, if they were present, in the body. The section of bowel containing the polyp was not opened while it was in Reagan

In removing a large polyp this afternoon from President Reagan's colon, Dr. Dale Oller and his team of surgeons did not know if it was malignant or benign, and so they acted according to prudent medical practice and proceeded as if the polyp was a cancer. Thus they removed not only the polyp but also about a two-foot-long piece of Mr. Reagan's bowel, which is tubular in shape. Then they sewed the two ends of the remaining bowel together, from the ileum, or the last section of the small bowel, to the transverse, or second section of the large bowel. The lack of a section of bowel is not expected to interfere with Mr. Reagan's bowel function, Dr. Oller, a Navy Captain, said after the operation. A diagram in some copies yesterday accompanying a description of President Reagan's surgery failed to show the full extent of the section of bowel removed. In the procedure, a right hemicolectomy, approximately two feet of bowel were removed, beginning with part of the transverse colon and continuing along the entire ascending colon, plus the cecum of the colon and part of the adjoining section of the small intestine called the ileum

[Reagan], now 74 years old, tolerated major surgery well four years ago, when surgeons at George Washington University Hospital opened his chest and removed a bullet that had lodged near his heart after an assassination attempt. Since then Reagan's doctors have repeatedly described him as being in excellent condition. The human intestine, or bowel, is divided into two portions, the large and the small intestine. The small intestine begins at the stomach and leads to the large intestine. The first portion of the large intestine is known as the cecum, and that is where Reagan's villous adenoma was found. To physicians knowledgeable about intestinal polyps but not connected with Reagan's case, the fact that polyp was too large to be removed during the colonoscopy suggested that it might be a sessile one, that is, attached directly to the intestinal wall at the base of the polyp and not attached by a stalk. If the polyp had been attached by a stalk to the intestinal wall, as many are, then it probably could have been removed by the snare in the colonoscope, no matter what its size

Polyps of the villous adenoma type are termed ''precancerous'' because they have a much higher chance of becoming malignant than other types of adenomas, or polyps. About 30 percent of villous adenomas become cancerous, in contrast to only 2 to 5 percent of all adenomas. Also, villous adenomas that are malignant tend to recur. To physicians knowledgeable about intestinal polyps but not connected with Mr. [Reagan]'s case, the fact that the polyp was too large to be removed during the colonoscopy suggested the possibility that it might be a sessile polyp, meaning that it is attached directly to the intestinal wall at the base of the polyp and not attached by a stalk. If the polyp had been attached by a stalk to the intestinal wall, as many are, then it probably could have been removed by the snare in the colonoscope, no matter what its size. Questions of whether Mr. Reagan should have undergone tests sooner have come up again this year because blood was found in tests of Mr. Reagan's stool, and blood is less likely to come from a smaller polyp than a larger one. Although the tests were repeated and were reported to show no evidence of further bleeding, polyps, which are one of many possible causes of blood in the stool, can bleed on an intermitten basis

[REAGAN], now 74, tolerated major surgery well four years ago when surgeons at George Washington University Hospital opened his chest and removed a bullet that had lodged near his heart after an assassination attempt. Since then, Reagan's doctors have repeatedly described his condition as excellent. Nevertheless, the operation comes as a surprise. It is needed because Reagan's doctors yesterday found a large polyp, probably of the villous adenoma type, while performing a standard medical procedure called a colonoscopy. The colonoscopy was done to remove a benign polyp in Reagan's colon, or large intestine, that was discovered last March, and also to look for other polyps. To physicians knowledgeable about intestinal polyps but not connected with Reagan's case, the fact that the polyp was too large to be removed during the colonoscopy suggested the possibility that it might be a sessile one, that is, attached directly to the intestinal wall at the base of the polyp and not attached by a stalk. If the polyp had been attached by a stalk to the intestinal wall, as many are, then it probably could have been removed by the snare in the colonoscope, no matter what its size

In removing a painless benign growth from President Reagan's colon tomorrow, his doctors at the Bethesda Naval Medical Center will be finishing a job they started earlier. Last year they removed a tiny benign polyp from the President's colon and last March they found another, the one that is to be removed. It was by using such a tube in routine medical checkups last year and last March that doctors detected a tiny polyp in Mr. Reagan's colon at each examination. A portion of each polyp was removed and subsequent pathological tests done with the aid of a microscope showed that both were benign, or noncancerous. In the most recent examination in March, doctors found evidence of blood in Mr. Reagan's stool. Additional tests were done after the President ate a meat-free diet for several days. These tests were done to determine whether the laboratory results had been so-called ''false positives'' as a result of blood in meat

Mr. [William J. Schroeder] is walking in the halls with assistance. Dr. William C. DeVries, the surgeon who heads the artificial heart implant program at the hospital, said yesterday that he believed Mr. Schroeder's speech was better than it had been before he moved to an apartment across the street from the hospital in April. Mr. [Murray P. Haydon] still requires assistance from the respirator for ''rare periods'' lasting ''only a few hours,'' Mrs. [Donna Hazle] said. But for the most part over the last four weeks he has been breathing without its help, she said. She described Dr. DeVries's team as happy about Mr. Haydon's progress and said no date had been set for him to move from the coronary care unit to a room elsewhere in the hospital

AT least 43 people died recently after eating a Mexican-style cheese containing the bacteria Listeria monocytogenes, one of the most mysterious of all microbes. The outbreak primarily affected California residents and is still under investigation. It highlights how much even the most sophisticated doctors have yet to learn about this microbe and all the others that cause the myriad infectious diseases. Many experts mistakenly believed that infectious diseases would no longer be important after the advent of antibiotics and immunizations. In reporting a recent outbreak of listeriosis involving 49 people in Massachusetts, Federal epidemiologists raised questions about the ability of pasteurization, even when properly carried out, to kill a large number of Listeria monocytogenes bacteria in contaminated raw milk. There are three general ways that milk can be contaminated. A cow infected with listeria or other micro-organisms may deliver contaminated milk. Or, if the cow has infected teats, the milk may be delivered sterile but becomes contaminated as a result of a milker's handling of the infected teats. Finally, contamination may occur at any point from the time it is pasteurized to the time it is drunk