It has been stated that the three elements that go into major biomedical discoveries are luck, persistence and insight. All three clearly played a role in the remarkable discovery immortalized with the eponymous term Arias-Stella reaction. Luck undoubtedly played a part by facing a budding pathologist with a morphologic change which, although not exceptional, it is certainly not common. Many pathologists have gone through their entire training process without having seen one. Here is where the component of insight plays a decisive role. The alteration that the young Arias-Stella had seen was clearly not a new phenomenon. Undoubtedly it had been seen by many others, including perhaps some of his peers and teachers. The key difference is that Arias-Stella had the intuition that the change he was observed was something distinct, reproducible and identifiable, different from all the other alterations that he had seen before in his own material and in the books. This is not exactly he most likely conclusion to reach y a relatively inexperienced worker, who knows has yet to be faced with hundreds of other endometrial alterations already documented in the literature. Actually, it takes a high degree of confidence – perhaps even a touch of cockiness – when faced with a peculiar morphologic change to conclude (or even to consider the possibility) that what one is seeing is something yet undescribed rather that the first encounter with an entity which the observer was simply unfamiliar with. It is here that the virtue of persistence enters to play its esential role. Having failed to impress other observers about the possible uniqueness of the observation, most pathologists would have shrugged their shoulders and forgotten all about. Not Dr. Arias-Stella. Far from being discouraged by the skepticism of his older colleagues, he went as far as showing the slides to Dr. Fred Stewart, from Memorial Hospital in New York, one of the luminaries of Surgical Pathology at the time. Stewart’s response was polite but not particularly encouraging. It could be taken literally as a stimulus to study the problem further or simply as polite form of dismissal. Not even this stopped Dr. Arias-Stella, who at that time was convinced that he had hit into something truly original. He went about in a stubborn but rigorously scientific fashion, proving in the process that a plain H&E slide can provide great insights into biology and pathology when there is a probing mind on the other side of the microscope eyepieces.

It has been commented that a new morphologic observation by an inquiring mind can prompt two different reactions, one of a practical nature (“What does it mean for the patient?”) and one of a mechanistic nature (“What could be the biologic significance and mechanism of this change?”), Lauren Ackerman or Arthur Purdy Stout would probably have asked the first question, whereas Pierre Masson or Averill Liebow would selected the second. Javier Arias-Stella went for both, and found the potential answers to them to be clinically significant and biologically fascinating. Never has an eponymic designation rendered more justice that naming this change “the Arias-Stella reaction”,  this proposal making of Arias-Stella the better known Latin American pathologist of his generation.

The fact that this discovery was made in Perú is in itself of interest. Relatively few are the Peruvians whose contributions to medicine have reached an international recognition: Alcides Carrion and his Peruvian verruca, Alberto Barton and his Bartonella, Carlos Jorge Medrano and his “chronic Mountain Sickness”, and the subject of this book. These are all notable contributions, but there is a substantial difference between the first three and the fourth. The former are endemic diseases of Perú and/or other mountainous countries, whereas the fourth is related to one of the most universal of biologic processes, i.e., pregnancy. This detail renders even more admirable the Arias-Stella’s feat. To paragraph Szent-Georgi, he saw what others had seen and thought what others had not tought.

It should be evident to the readers of this book that its author is a special individual, who possesses all of the intellectual qualities that Ramòn y Cajal required of a scientist: independent judgment, perseverance, passion for reputation, patriotism, and taste for scientific originality, Ramòn y Cajal added that it would be difficult to find an investigator willing to exchange the paternity of a scientific conquest for all the gold on earth, and Arias-Stella makes it abundantly clear in this work that he would not be one to depart from that almost sacred feeling.

Juan Rosai, M.D.
Milan, Italy