The following play important role in the diagnosis of early gastric carcinoma:
-screening "at risk" population
-advanced endoscopic techniques,
-recognition of subtle endoscopic abnormalities,  
-careful histopathological examination to identify the depth of invasion.
Following surgical resection, the average five year survival rate is almost 95%.
- Early gastric carcinoma is defined as carcinoma confined to the mucosa or submucosa irrespective of lymphnode involvement (corresponds to T1 gastric carcinoma).
- Macroscopic subypes (see diagram).  Often a combination of these three types are present.
- Depressed Type (IIC) is the commonest form of early gastric carcinoma.
- Histological features are similar to those of advanced carcinoma. Classified according to Lauren"s Classification into : intestinal, diffuse (signet ring cell) or mixed types.
- Type I and IIa : usually multiple lesions and are likely to be well-differentiated (intestinal type)
- Type IIc & III: Poorly differentiated or signet-ring cell type.
- Tumour behaviour can be predicted by the shape of advancing edge of tumour through the muscularis mucosae into the submucosa.
Early gastric carcinoma with a broad pushing edge (PEN A -subtype) has a poor prognosis.
Tumour with a sharp infiltrating edge (PEN B - subtype) has a better prognosis.   
- Histopathologists should be aware of the prognostic implications of the histological features.
- The biopsy must include the full thickness of the tumour and hence must be fully excised to determine whether the tumour fits into the definition of early gastric carcinoma.
-  Prognosis is related to depth of invasion. Deeper the penetration (into submucosa) greater the chance of metastases.
- Comment should be made on completeness of excision,lymphatic invasion and presence of ulceration (predictive of lymph node metastasis).
- Endoscopic mucosal resection is performed (mainly in Japan) in case of intramucosal early gastric carcinoma.
- Radical surgery is necessary in case of lymphnode metastasis.
- High grade dysplasia can be indistinguishable from early gastric carcinoma in biopsies.The two often co-exist in more than 80% cases.
- Differences exist in the criteria used to separate high grade dysplasia from intramucosal carcinoma between Japanese (rely on cytological and architectural features only) and Western pathologists (invasion of lamina propria must be present).