Lactic Acid

Although it was known that the organic acids are increased in cancer of the stomach, and that lactic acid frequently occurs, Boas1 must be credited with laying stress upon the presence of lactic acid in this affection; he even attributed a pathognomonic value to this symptom. According to this investigator, lactic acid, if not introduced in a preformed state with the food, but developing in the stomach, occurs exclusively in cancer of this organ. After a thorough washing of the stomach, Boas gives the patient a test meal, consisting of a plate of barley soup. One hour afterward the gastric contents are obtained and examined, either by the Uffelmann test or by Boas' method, as to the presence of lactic acid. This test meal does not contain any lactic acid, and if the latter is found to be present then it must have been produced in the stomach. Boas does not deny that there are cancers of the stomach which do not show this symptom. As a rule, these are cases in which hydrochloric acid is found to be present. The occurrence of lactic acid, however, is, according to Boas, a specific sign. Many writers have of late investigated the question of the appearance of this acid.

Most of them agree that lactic acid exists in large quantities in the majority of cases of gastric cancer, but that it is by no means a specific sign. Klein-perer,1 Thayer,2 Rosenheim,3 and myself,4 have pub lished cases of non-malignant gastric troubles in which lactic acid was found in the gastric contents.

1J. Boas: Deutsche med. Wochenschr., 1892, No. 17.

The absence of free hydrochloric acid and the presence of lactic acid, although they are, as we have seen, not pathognomonic, are, however, of importance and frequently help to establish the correct diagnosis.

The diagnosis of cancer can be positively made under the following conditions:

1. If particles of tumor are found (in the wash-water or in the tube), which under the microscope reveal the characteristic picture of a malignant growth.

2. The presence of a more or less large tumor with an uneven surface, belonging to the stomach and associated with dyspeptic symptoms.

3. The presence of a tumor associated with frequent haematemesis.

1 Klemperer: Deutsche med. Woehonsohr., 1895.

2 Thayer: Johns Hopkins Hosp. Mullet., 1893, No. 31.

3 Rosenheim: Berl. klin. Wochenschr.. 1894, No. 39.

4 Max Kin horn: "Stenosis of the Pylorus." Medical Record, January 19th, 1895.

4. Constant pains, frequent vomiting, ischochymia, emaciation - all these symptoms being quite permanent and not extending over too long a period of time (six months to one year).

5. Tumor and ischochymia.

6. Emaciation, ischochymia, presence of lactic acid.

7. Constant anorexia and pains, not yielding to treatment, accompanied by frequent small hemorrhages (of coffee-ground color).

Differential Diagnosis

In cases in which a tumor exists it is necessary to determine whether it originates from the stomach or some other organ; and if it has its seat in the stomach, whether it is of benign or malignant character. The first question, as to which organ a tumor belongs to, has been discussed above. As regards the second question, we shall have to differentiate between a tumor situated within the stomach proper and one at the pylorus. Benign tumors, like fibroma, myoma, and lipoma1 situated within the stomach, or foreign bodies, like a gastrolith or a mass of hair, which may simulate a neoplasm are of extremely rare occurrence and need hardly be taken into consideration when making the diagnosis. In tumors situated at the pylorus we meet much more frequently conditions of a benign type, such as cicatricial thickening or simple hypertrophy. The size of the tumor, the condition of its surface, whether smooth or nodular, will frequently help to decide this question. The tumor in benign processes is usually not very large (about walnut size), smooth, and does not grow; while malignant growths are larger, frequently present an uneven surface, and increase in size. These points are, however, not enough to form a decisive opinion, and they must be supplemented by such data as can be obtained.

Thus, long duration of the sickness - two or three years and more - speaks in favor of a benign process, while a short duration - six months and so on - rather favors the view of a malignant process.

1 Syphilitic gummatous tumors of the stomach also belong to this class. I have observed a case of this kind very recently. The presence of other luetic manifestations will remind us of this possibility.

In all instances in which a tumor is absent the differential diagnosis of cancer will have to exclude ulcer, benign stenosis of the pylorus (not palpable), chronic gastric catarrh, achylia gastrica, and very severe forms of gastric neurasthenia.