On the cytology of malignant growths

Abstract

In the winter of 1903 we presented to the Royal Society a preliminary account of the results of our investigations on the cytology of malignant or cancerous growths, in which we stated that we had recognised a certain type of nuclear division, known as they heterotype, to occur in the cells of these pathological tissues. Hitherto, this peculiar kind of mitosis, characterised by a reduction to one-half of the normal number of the somatic chromosomes , together with highly characteristic forms of their bodies themselves, had only been known to occur in connection with the so-called reduction division, that, in animals, immediately, precedes the formation of the sexual elements. These reduction divisions constitute a well-known phase in the life cycle of all higher animals and plants, consisting invariably of two consecutive stages, which are distinguished as heterotype and homotype mitoses respectively. As these tow mitoses constitute so well-defined a stage in the cellular life history of the higher organisms, we have proposed to emphasise this fact by the introduction of the term “maiosis,” designating the stage itself as the maiotic phase. Thus the heterotype and homotype mitosis form respectively the first and second maiotic division. We propose, in the present paper, to deal more fully with the cytological details of malignant growths, in so far as we have been able to investigate them, and we shall endeavour briefly to point out the conclusions that we think may legitimately be drawn from them. In doing this we desire, as far as possible, to confine ourselves to a consideration of the evidence we have been able personally to obtain, and we propose to avoid a general discussion of the numerous theories as to the ætiology of the disease, and especially of those that are based on clinical experience, except in so far as our own observations seem to throw light on those matters. We are fully aware that in pursuing such a course, we lay ourselves open to the charge of incompleteness, and of unduly neglecting the views of others. But an attempt to deal at all adequately with the vast literature that has grown up around the subject of cancer would involve a very lengthy, and probably not a correspondingly fruitful, discussion.