Individuality versus conformity. Is perfection necessary in staging and prognostic classifications of specific primary extranodal lymphomas?

Editorial Individuality versus conformity. Is perfection necessary in staging and prognostic classifications of specific primary extranodal lymphomas? "Perfection is I he enemy of the good." Voltaire The two papers in this issue that address the management of primary gastric lymphoma have more in common than does the disease under discussion. Both consider questions surrounding the management of a relatively common presentation that accounts for approximately 20%-30% of all patients with localised extranodal lymphoma [1]. However, it is still a relatively rare presentation that accounts for no more than 5% of all new lymphoma cases [1, 2]. The authors analyse the outcomes and prog-nostic factors in heterogeneous groups of patients collected over 16-25 years and managed with a variety of treatment methods. Both papers propose some modifications to the current staging or prognostic systems. Cortelazzo et al. report the outcomes in 312 patients with stage I and II diffuse large-cell B-cell lymphoma of the stomach, treated in Switzerland and Italy with a variety of approaches over 25 years, and propose a new 'stage-modified' International Prognostic Index. Ibrahim et al. report the outcomes in 185 patients with stage I-IV primary gastric lymphoma treated in Saudi Arabia with a variety of approaches between 1982 and 1998, and propose their own version of 'prognostic index' while at the same time embracing the 'Lugano staging classifica-tion' for gastrointestinal lymphoma. Both authors correctly identify that the extent of lymph node involvement affects the outcome in gastric lymphoma. There is also evidence that the extent of nodal involvement is of prognostic significance in both Hodgkin's disease and non-Hodgkin's lymphomas. In fact, Vera Peters proposed the separation of the 'localised stage II' from the 'extensive stage II' lymphomas [3-5]. The Ann Arbor staging classification was agreed upon at a meeting of experts and interested parties that took place in Ann Arbor Michigan in 1971 and has been put to use for almost 30 years [6]. The arbitrary distinction between stage II and stage III based on the location of nodal involvement in relation to the diaphragm was a pragmatic decision driven by issues related to the application of radiation therapy, then the most prevalent form of treatment. The Ann Arbor classification although not perfect, has allowed the clinicians dealing with lymphomas to communicate in an unambiguous manner for many years. Indeed, the use of staging classification in lym-phomas preceded the use of uniform, internationally recognised staging classifications in …