The long term outcome of gastric non-invasive neoplasia

Abstract

Background: The cancer risk associated with gastric non-invasive neoplasia (formerly dysplasia) is debated. This prospective long term follow up study investigates the clinicopathological behaviour of non-invasive gastric neoplasia (and related lesions), focusing on the cancer risk associated with each different histological phenotype.

Patients and methods: A total of 118 consecutive cases (nine indefinite for non- invasive neoplasia; 90 low grade non-invasive neoplasia; 16 high grade non- invasive neoplasia; and three suspicious for invasive adenocarcinoma) with a histological follow up of more than 12 months (average 52 months; range 12-206) were prospectively followed up with a standardised protocol. Patients in whom gastric cancer was detected within 12 months from the initial diagnosis of non-invasive neoplasia were excluded, assuming that invasive carcinoma had been missed at the initial endoscopy procedure.

Results: Non-invasive neoplasia was no longer detectable in 57/118 cases (48%), was unchanged in 32 (30%), and evolved into gastric cancer in 20 patients (17%). Evolution to invasive adenocarcinoma was documented in both low and high grade non-invasive neoplastic lesions (8/90 low grade; 11/16 high grade) and correlated with histological severity (low versus high grade) at baseline (p<0.001). Seventy five per cent of cancers occurring during the long term follow up were stage I.

Conclusions: The risk of invasive gastric cancer increases with the histological grade of the non-invasive neoplasia. Following up non-invasive gastric neoplasia increases the likelihood of gastric cancer being detected in its early stages.

Figure 1

Follow up protocol. Lesions indefinite for non-invasive neoplasia were followed up as scheduled until the case was assigned to the non-neoplastic or neoplastic non-invasive category. Patients were considered disease free after two successive endoscopy/biopsy procedures consistently negative for non-invasive neoplasia. When the grade of the lesion was consistently lower than before in two successive tests (that is, “regression” from high grade to low grade), the patient was followed up in accordance with the recommendations for low grade non-invasive neoplasia. High grade lesions detected during the follow up of low grade non-invasive neoplasia were subsequently followed up as high grade lesions.

Figure 2

Gastric biopsy sampling protocol (dots show sites of biopsy). During follow up, after an initial diagnosis of non-invasive neoplasia, all patients underwent endoscopy with multiple biopsy sampling; 1–3 samples were obtained from each site. The sampling protocol demands further sampling of any focal lesions.

Figure 3

Low grade versus high grade gastric non-invasive neoplasia: evolution into invasive adenocarcinoma (p<0.001).