A conglomerate of cases may be defined as the onset of a number of cases of a disease larger than would be expected for a certain population group, geographical area or a certain timeframe. In the case of cancer, the study of conglomerates entails a number of specific characteristics as compared to other groups of diseases. This work is aimed at proposing a protocol affording the possibility of conducting the study of cancer conglomerates in time and/or space. This article is illustrated with a practical application in the case of the Campdorà District in Girona. Following a proposed protocol for the study of conglomerates, a description is provided of several statistical tools making it possible to draw a comparison among the existence of time-related groupings, as well as the related risk. During the period studied (1994-2002), no excessive statistically significant number of cancer cases seemed to have occurred in the Campdorà District in Girona.