Pathology: The Last Word

To most laymen, a pathologist is either a Sherlock Holmes type called in to study a corpse and solve a murder mystery or the man in the laboratory at the end of the corridor who reports to the surgeon, “It’s all right to close up that patient—the growth is benign.” But between those extremes the pathologist’s work proliferates endlessly. In Chicago last week, the American Society of Clinical Pathologists and the College of American Pathologists got together in annual meeting to trade expertise on the whole range of human ills and, incidentally, to sharpen up their public image.

By definition, pathology is the study of disease, a statement that scarcely distinguishes it from other branches of medicine. Pathologists try to make their efforts a little clearer with a lot more words: “Observation and understanding of the progress of disease by morphological, microscopic, chemical, microbiologic, serologic or any other type of laboratory examination made on the patient or on any material obtained from the patient.” The list ranges wide enough to include work for some 5,500 U.S. physicians qualified as specialists in pathology.

Slice & Spin. Just as they cut tiny pieces of human tissue into microscopically thin slices to study the progress of disease, pathologists tend to slice up their own specialty. One main branch is called anatomic pathology, and its devotees concern themselves with structural changes in tissues, usually seen at autopsy. But it is also the anatomic pathologist who examines the piece of tissue from a patient still on the operating table and tells the surgeon whether or not it is cancerous.

The clinical pathologist runs the laboratories where blood tests are made, makes many of the tissue examinations himself, and studies minute changes in obscure body fluids. Both these classes of pathologists are “doctors’ doctors.” In their own cliche, they are the ones who have the last word. Farthest removed from the public are the comparative pathologists, who concern themselves with such basic problems as what disease is and why organisms grow old. Whatever part of their specialty they practice, pathologists learn to use a dazzling array of gadgets designed to help them find answers to forbiddingly difficult questions:

>Centrifuges to spin out the cells from the blood’s plasma.

>Ultracentrifuges to sort out fat-protein combines in the blood by their molecular weights.

>Microtomes that work like miniature bacon slicers on a piece of tissue no bigger than the tip of a baby’s pinkie and cut it into slivers each less than one twenty-five-thousandth of an inch thick. >

>Dyes for staining tissues and cells and even individual germs, including some to make suspect substances glow under ultraviolet rays.

Public & Private. In their wide-ranging surveys, the Chicago conferees reported on new tests for infectious mononucleosis, the beginning signs of cancer in the mouth, nickel workers’ lung cancer, the hyaline membrane disease that killed President Kennedy’s infant son two months ago, and a possible mechanism to explain how a violent reaction against a food protein may be the cause of mysterious infant deaths (TIME, Oct. 4).

Inevitably, because blood is a whole pharmacopoeia in itself, the hematologists had a field day. Dr. Leon N. Sussman of Manhattan’s Beth Israel Hospital pointed out that besides the familiar ABO and Rh factors noted on every serviceman’s dog tag and blood donor’s identity card, there are no fewer than 15 other “public”* factors widely distributed in human blood. By computing all the possible combinations of these, Dr. Sussman arrived at the startling figure of 57.6 million different kinds of people distinguishable by telltale proteins in their blood. Because there undoubtedly are still other factors not yet recognized, he doubts that any two people in the world, except identical twins, have identical blood.

The virtual indestructibility of blood-group markers is shown daily by forensic pathologists who solve a crime by analyzing a single spot of months-old blood. Less commonly known, said Dr. Sussman, is that 80% of people have similar substances, from which ABO grouping can be determined, in their sputum, saliva, nasal secretions, urine and seminal fluid. To prove it in his laboratory, Dr. Sussman got an assistant to lick a postage stamp and stick it on a piece of paper. This was left on the lab table, exposed to air, sun and dust. At the end of a month, one-quarter of the stamp’s back yielded enough material to identify the licker as type B.

* As distinct from 13 recognized “private” factors, which have been found only in certain families.