224 



SCIENCE PROGRESS 



time, results in cancer. Persons who work with X-ray 

 apparatus have in some cases developed cancer in parts of 

 the body which have been continuously irritated and inflamed 

 for years by the action of the rays. The chronic inflammation 

 accompanying syphilis is regarded by many, probably with 

 reason, as often resulting in cancer. 



There is overwhelming evidence that cancer is commonly 

 incident to several different occupations and habits in all of 

 which chronic inflammation of some part of the body is involved, 

 cancer occurring in the part affected. 



That cancer should follow upon prolonged inflammation is 

 compatible with the view that the cells have passed out of 

 somatic co-ordination. Apparently all the somatic or body 

 cells are destined to disintegrate within a limited space of 

 time. In some groups of cells — those forming the skin for 

 instance — the multiplication goes on actively throughout the 

 life of the organism ; in other groups, multiplication either 

 does not take place or is rare in the adult. Chronic inflam- 

 mation causes the groups of cells affected to multiply more than 

 they would under normal conditions. It seems probable that 

 the powers of normal proliferation of any given group of cells 

 included in the body are limited and that when a certain number 

 of cell generations have been produced the offspring tend to 

 escape from somatic co-ordination as a stage on the way towards 

 fertilisation. Having passed out of somatic co-ordination, the 

 cells possess novel properties and, as the experimental work 

 already described shows, are able to grow and multiply in a 

 suitable environment just like the cells of grafts or cuttings 

 of plants. The suitable environment is the body of the animal 

 in which they arose or a body similar to it ; and they live 

 in it as separate individuals in a parasitic manner. 



In every case in which a generally accepted cause of the 

 disease is apparent the cancer is external, that is upon or 

 near the surface of the body. It is quite likely that chronic 

 inflammation is the cause of internal cancer also and various 

 suggestions have been made on these lines. Chronic alcoholism 

 resulting in inflammation and the production of scar tissue in 

 the liver might well condition cancer, as also might chronic 

 inflammation of the lining of the stomach. Primary cancer 

 of the liver is very rare, however. Cancer of the stomach is 

 common in men. Ulceration of the stomach is commonest 



