1. Peculiarities of the lesion. A very small lesion or one that is primarily intramural or one that is located in one of the relatively blind areas of the stomach (e.g., cardia, fundus, anterior or posterior walls) may easily escape detection.

2. Lack of follow-up. Unquestioning faith in a single x-ray examination can be quite hazardous. In the final analysis it is the judgment of the clinician familiar with the entire context of the case which must dictate proper diagnosis and treatment. Thus in certain clinical settings the physician must override benign, equivocal, or even negative x-ray findings and insist on repeat gastrointestinal series, other diagnostic studies, and occasionally exploratory laparotomy before being satisfied with the diagnosis. A "wait-and-see" attitude is all too often disastrous.

3. Limited competence of the examiner. It should be remembered, however, that at times the diagnosis may elude any and all examiners.

4. Imperfection in technique. This is usually related to the competence of the examiner, but occasionally a substandard examination may result from factors such as failure of the patient to fast, gastric hypersecretion, etc.

Cytology Indications

Ideally, cytologic examination of the gastric contents should be employed in the routine diagnostic work-up of all patients in whom there exists any suspicion of stomach cancer. Compromises are often required by particular circumstances, however.

1. For example, if surgery is clearly indicated by reason of other findings strongly supporting a diagnosis of cancer or because of complications or intractable symptoms regardless of the diagnosis, cytology may be waived since laparotomy would be carried out whatever the cytologic study showed. The advantages to the responsible physician and surgeon of having an unequivocal preoperative diagnosis should not be underestimated, however.

2. On the other hand, when all signs point toward a policy of no surgery, it is doubly important to require proper cytologic study. It is the only way short of operation or gastroscopic biopsy to obtain unequivocal tissue proof of cancer. For example:

(a) The lesion may be thought to be benign. The physician who urges on a patient a medical regimen for what could be a malignant lesion must insist on having every diagnostic fact at his disposal before making this decision. This is especially true if one realizes that the equivocal lesion is precisely the type of cancer which enjoys the highest cure rate if proper treatment is undertaken.

(b) The lesion may be thought to be inoperable cancer. Contrariwise, the decision of the physician who advises against surgery must stand on the firmest possible ground. An "unequivocal" diagnosis of "inoperable" cancer occasionally proves to be tragically wrong. The lesion may turn out to be a primary lymphoma of the stomach which may have a fairly high survival rate following surgery and/or x-ray treatment. Almost as bad, the lesion eventually may prove to be benign and the physician may find himself trying to undo the torments of his mistakenly fatal diagnosis.

To summarize, the indications for cytologic examination of gastric contents are as follows:

1. Ideally, it should be part of the routine work-up on all patients with suspected stomach cancer.

2. If cytology must be somewhat restricted:

(a) It may be omitted when surgery is contemplated in any event.

(b) But it should still be done on all equivocal lesions for which surgery is not being recommended.

Contraindications

As in the case of the gastrointestinal series, there are few contraindications to cytologic study, although the presence of active gastric or esophageal bleeding, obstruction, or perforation may require modification in timing or technique- and occasionally avoidance of the procedure altogether.