Diagnosis of gastric cancer

Plasma concentration of tissue inhibitor of matrix metalloproteinase 1 in patients with colorectal carcinoma

BACKGROUND

The expression of tissue inhibitor of matrix metalloproteinase (TIMP) 1 in tumour tissue from patients with colorectal carcinoma has been reported to be related to disease progression. However, the clinical significance of plasma TIMP-1 has not been fully elucidated.

METHODS

The plasma level of TIMP-1 protein was determined by enzyme-linked immunosorbent assay in samples from 54 patients who underwent resection of the primary tumour.

RESULTS

Plasma TIMP-1 levels were associated significantly with depth of invasion and metastasis to lymph nodes and liver. Circulating TIMP-1 levels were significantly higher in patients with serosal invasion, liver metastases and Dukes' stage C tumours. Using a cut-off value of 160 ng/ml, serosal invasion and Dukes' C stage could be predicted with an accuracy of 68.5 per cent. With a cut-off value of 170 ng/ml, metastasis to the lymph node and liver could be predicted with an accuracy of 66.7 and 70.4 per cent respectively. These values were greater than those for carcinoembryonic antigen and CA19-9.

CONCLUSION

These data suggest that the plasma concentration of TIMP-1 correlates with both invasion and metastasis in patients with colorectal carcinoma.

Tissue inhibitor of matrix metalloproteinase-1 in the plasma of patients with gastric carcinoma. A possible marker for serosal invasion and metastasis

BACKGROUND

Expression of the tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) in tumor tissue from patients with gastric carcinoma has been reported to be related to disease progression. However, to the authors' knowledge the clinical significance of plasma TIMP-1 concentrations in these patients has not been clarified.

METHODS

Concentrations of TIMP-1 protein were examined by enzyme-linked immunoadsorbent assay in plasma samples from 149 patients who underwent resection of their primary tumors and from 18 patients with nonresected or recurrent disease.

RESULTS

In the 149 patients whose primary tumors were resected, plasma TIMP-1 concentration was associated significantly with a variety of pathologic factors including macroscopic type, depth of invasion, lymph node and peritoneal metastases, vessel invasion, pattern of tumor infiltration into surround ing tissue, and disease stage. Plasma TIMP-1 concentration was significantly higher in patients with serosal invasion, lymph node metastasis, peritoneal dissemination, or liver metastasis than in those without these factors. Neither carcinoembryonic antigen (CEA) nor CA 19-9 concentrations appeared to be related to these measures of disease progression. In the 18 patients with nonresected or recurrent disease, TIMP-1, CEA, and CA 19-9 were similarly sensitive in predicting peritoneal, liver, and lymph node metastases. The combination of these three factors was able to detect 73.3% of patients with peritoneal metastasis, 83.3% of patients with liver metastasis, and 88.9% of patients with disease recurrence.

CONCLUSIONS

In patients with gastric carcinoma, plasma concentration of TIMP-1 appears to correlate with both serosal invasion and metastasis.

Gastroscopic cytology and biopsies in diagnosis of gastric malignancies

The outcome in gastric malignancy has changed in recent years owing to its early and accurate diagnosis employing fiber-optic endoscopy and histocytology. One hundred and two subjects with endoscopic demonstration of various gastric lesions were subjected for brush cytology and multiple biopsies. Observing a high degree of specificity, the accuracy of brush cytology was 81% and histology 72% with cumulative diagnostic yield of 91%. There was no false-positive report with cytology; histology, however, gave three false-positive results. The present study thus confirms the high diagnostic accuracy of brush cytology combined with multiple biopsies in gastric malignancies.

Accuracy of the first endoscopic procedure in the differential diagnosis of gastric lesions

The accuracy of endoscopy and directed biopsy in the differential diagnosis of gastric lesions was evaluated by comparing the diagnoses of one endoscopic procedure (endoscopy and multiple directed biopsies) with the definitive diagnoses in 333 patients. The overall endoscopic and bioptic accuracy rate for all patients amounted to 98.8%. Separate accuracy rates of endoscopy alone and biopsy were 86.5% and 94.9%, respectively. The reliability of endoscopy was similar in the diagnosis of malignant and benign lesions (86% and 89%). Endoscopic biopsy was correct in 99.1+ of benign lesions and in 86% of malignancies. False negative rates were 3.9% for endoscopy and 4.0% for biopsy. It is concluded that one endoscopic procedure is a highly reliable method in the differential diagnosis of benign and malignant gastric lesions.

Comparison of brush cytology before or after biopsy for diagnosis of gastric carcinoma

A randomized trial has compared the results of brush cytology before or after biopsy in patients with solitary gastric lesions. One hundred and eleven carcinomas were identified in 324 patients. False positive histological reports were recorded in 2 patients but there were no false positive cytology results. The cumulative accuracy of biopsy and cytology in patients with carcinoma was 97 per cent, which was significantly better than biopsy alone (83 per cent, P less than 0.001) or cytology alone (87 per cent, P less than 0.001). The cumulative results of brushing before biopsy were significantly better than results obtained by brushing after biopsy (P less than 0.05) and indicate that brush cytology should normally be performed before biopsy.

Preventing malignant-cell transfer during endoscopic brush cytology

Transfer of malignant cells on cytology brushes was responsible for false positive cytology reports in 4 patients. In 24 examinations of cytology brushes after patients with gastric carcinoma had been previously endoscoped, malignant cells were identified on 7 occasions. Satisfactory irradication of malignant cells was achieved by autoclaving the brushes for 15 min, not by cleaning with chlorhexidine or pancreatin. Although these observations may argue against the use of non-disposable brushes, non-disposable brushes provide a higher yield of cells and are cheaper than disposable brushes.

Diagnostic value of biopsy, guided lavage, and brush cytology in esophagogastroscopy

In a prospective study 96 patients with esophageal and gastric lesions were investigated by multiple endoscopic biopsy, brush cytology, and guided lavage cytology. The aim was to evaluate the diagnostic accuracy of each of these methods in a prospective study. 50 malignant and 46 benign lesions were found. The final diagnosis was proven by operation or autopsy in 53 cases, by multiple endoscopic follow-up in 31, and by clinical control in 8. No follow-up was possible in 4 patients. The malignant lesions were diagnosed by multilple biopsy in 86.0%, by brush cytology in 84.0%, and by lavage cytology in 50.0%. The diagnostic yield of lavage cytology was thus significantly lower (P less than 0.01). It is concluded that a combination of multiple biopsy and brush cytology is the most valuable aid in endoscopic diagnisis of esophageal and gastric malignancy with a diagnostic accuracy of 96%.

Transfer of computer-aided diagnosis of dyspepsia from one geographical area to another

This paper reports a comparison in Airedale District General Hospital between computer-aided diagnosis of dyspepsia and endoscopy in a prospective unselected series of 165 patients. Patients were interviewed immediately before endoscopy and the findings analysed by a small desk-top computer-aided system. Each 'new' patient was compared by the computer with a group of 360 similar patients from Leeds (25 miles away). Overall, 83% of the positive lesions found at endoscopy were correctly predicted by the computer, including all but three of the 22 cases of gastric cancer. It is suggested (1) that there is little loss of accuracy in transferring the computer-aided system from one locality to another; and (2) that a computer-aided analysis of the patient interview may be of value in selecting 'high-risk' patients for intensive investigation.

Importance of the site of endoscopic gastric biopsy in ulcerating lesions of the stomach

Twenty freshly resected stomach specimens, each containing an ulcerated carcinoma, were studied in an attempt to determine the best site for gastric biopsy. Using endoscopic biopsy forceps multiple biopsies were obtained from various sites around the ulcer. Carcinoma was detected with similar frequency in biopsies from the slough and from the rim of the ulcer. The positive biopsy rate was increased to 95% when the results from the rim and the slough were combined. It is suggested that the diagnostic accuracy of endoscopic gastric biopsy can be improved by taking biopsies from both the rim and the slough of an ulcer.