Why medical case reports?

Medicine is built up of single cases. Individual patients-single cases-are the essence of what medicine deals with. Every patient is important, and every case can be a lesson. Clinician, researcher, and epidemiologist Alvan Feinstein said, "In caring for patients, clinicians constantly perform experiments. During a single week of active practice, a busy clinician conducts more experiments than most of his laboratory colleagues do in a year."(1) Medicine stretches between the intertwined poles of being developed in the laboratories of the pharmaceutical industry and in the clinical practice of the "clinical champions"-the innovative clinician, therapist, nurse, or midwife. While the laboratory testing route (pharmacology, quality assessment, phase I-IV trials) is well established, what about the significant clinical observations? How can they be presented scientifically?