CD99 and adenocarcinoma: The adenocarcinoma component was strongly and diffusely immunoreactive (3+, cytoplasmic staining) for CK7 (Figure 6D) and pancytokeratin; weakly and focally immunoreactive (1+, cytoplasmic staining) for CD56 and synaptophysin; and negative for CA-IX, CD99, CDX2, chromogranin, CK20 and SMA.