CD9 and nasopharyngeal carcinoma: In turn, among malignant epithelial tumors (n = 7), the four adrenal carcinomas were heterogeneously positive for CD56, EpCAM, CD90, CD9, CD81, and CD271, while they were negative for GD2, CD99, nuMyoD1, numyogenin, CD57, CD10, and CD58; neoplastic cells in 2/3 nasopharyngeal carcinomas expressed EpCAM, CD81, and CD9 in the absence of GD2, nuMyoD1, numyogenin, CD90, CD271, and CD99, one case being CD56+ and the other CD56− (Figure 3 and Table S2).