Clinical and prognostic characteristics of papillary clear carcinoma of stomach.

Papillary clear carcinoma (PCC), a variant of gastric papillary adenocarcinoma, demonstrates the histologic features of cancer cells with clear cytoplasm and no nuclear polarity, resembling the primitive gut epithelium of the fetus. To clarify the clinical and prognostic characteristics of PCC, we examined operative specimens from 73 patients with gastric papillary adenocarcinoma. Light microscopic examination of hematoxylin and eosin (H&E) stained sections of specimens from 15 patients revealed the features of PCC. The patients with PCC demonstrated a higher incidence of Type 3 gross appearance, tumor invasion into the muscularis propria or beyond, involvement of distal lymph nodes, liver metastasis, elevated serum AFP concentrations, and palliative resections. In two subsets of patients who underwent curative resections of tumors invading the muscularis propria or beyond, those with PCC were found to have a significantly lower survival rate than those with other types of papillary adenocarcinoma (P < 0.05). PCC histology was a significant prognostic determinant according to multivariate analysis with the Cox proportional hazards model. We conclude that this subclassification of papillary adenocarcinoma, based on the cellular findings, is a useful prognostic indicator, and that intensive adjuvant therapy may be indicated for patients with the features of PCC, even if they have undergone curative resections.