Cellular differentiation, secretory and proliferative activities of craniopharyngiomas

The cellular differentiation of craniopharyngiomas was studied immunohistochemically by determining the expression of cytokeratins. Alcian-Blue staining was used to assess secretory activity and expression of AgNORs and PCNA as indicators of proliferative activity. Both, tumors of the adamantinomatous type and of the squamous type expressed complex type cytokeratins, with skin type differentiation being noted in some cases. In addition, epidermal differentiation of cytokeratins was found in the squamous types. Intracellular Alcian-Blue staining was limited to apical cells of tumors of the squamous type. Neither AgNORs staining nor PCNA staining proved statistically significant results with respect to the histological type of tumor or patient's age. However, PCNA staining was predominantly noted in basal cells of the squamous type tumors. Although their ultimate significance remains to be established, the results presented provide additional evidence with regard to the possible origin of both craniopharyngioma types, and suggest the potential value of some of the parameters studied as prognostic indicators.