Epilogue: The Diseased Breast Lobe in the Context of X-Chromosome Inactivation and Differentiation Waves

Abstract

The debate over whether cancer starts in a single cell (Hahn and Weinberg 2002) or is a multifocal disease (the latter variously referred to as the multicellular model [Attolini and Michor 2009] or field theory [Soto et al. 2008]) has a long history. This book, Breast Cancer: A Lobar Disease, may be a stepping stone toward trying to resolve this long-standing issue. My own work on breast cancer detection has been based on the assumption, at first sight contrary to Tibor Tot’s sick lobe hypothesis, that targeting a single small lesion will halt breast cancer, and the epidemiological evidence would seem to point that way. And yet, as can be seen by the dialogue with Tot and Vincent Vinh-Hung at the end of my chapter (Gordon 2010), more subtle considerations may let us see breast cancer both ways, i.e., that they are not mutually exclusive. It may be that one could either stop breast cancer recurrence for an extended time by ablating a single small tumor, or for the remainder of a women’s life by removing the whole of a sick lobe, difficult outcomes to distinguish. As in the debate over total mastectomy versus lumpectomy (Lerner 2001), both may prove clinically equivalent in terms of prolongation of life. At least, lobectomy is less disfiguring than mastectomy, so passions need not run as high. Much work remains ahead to determine the outcome of this debate, though we will see what we can tease out of retrospective epidemiological data (Vinh-Hung et al. 2010).