The examination of the gastric contents as an aid to the diagnosis of carcinoma of the stomach
Dunlop, Derek Melville
As the result of my investigations the following conclusions have been arrived at. It must he realised, however, that, as it has only been possible to study a limited number of oases, certain of these conclusions must not be taken as dogmatic assertions, but rather as expressions of opinion based upon a limited number of results.1. Gastric carcinoma may be diagnosed or excluded in the vast majority of cases, by examination of the stomach contents alone.E. The results of the gastric analysis on which importance should be placed, in the diagnosis of this disease, are the presence of: (a) Achlorhydria. (b) Lactic acid. (c) Blood. (d) Evidences of stagnation.3. Absence of free acid and the presence of lactic acid are found in the great majority of patients suffering from gastric carcinoma, and such a dual finding, with the exception of carcinoma of the oesophagus, probably occurs in no other condition.4. The absence of lactic acid in stomach contents which show no free acid, or the discovery of large quantities of free hydrochloric acid make the presence of gastric carcinoma exceedingly improbable.5. The absence of free acid and the presence of lactic acid is not necessarily evidence of an advanced condition of the carcinoma, nor is the presence of free acid necessarily evidence of an early stage in the growth.6. Lactic acid found in the stomach is not invariably caused by the fermentation of stagnating gastric contents, but may be sareolaetic acid produced by the tissues involved by the growth. It may therefore occur in the stomach contents when no pyloric stenosis is present.7. Graphs of the total acidity curve in gastric carcinoma can usually be distinguished from those found in pernicious anaemia and primary achylia gastrica from the shape of the curve.8. The congo red and dimethyl tests for free hydrochloric acid in the gastric contents are not trustworthy, since: (a) They do not indicate free hydrochloric acid when it is present in very small quantities. (b) They react to large quantities of lactic acid in the same way as they react to free hydrochloric acid.9. GUNZBERG'S test, when the reagent is freshly prepared, is an entirely reliable one for the presence of free hydrochloric acid.10. UFFELMANN'S test for lactic acid is valueless, as it gives a positive reaction with many other substances, which may be found in the stomach contents, besides lactic acid.11. MACLEAN'S test for lactic acid is simple and trustworthy.