Phytohemagglutinin-binding sites in the skin. A useful histochemical marker of acrosyringium and distal portions of intradermal sweat ducts.

Phytohemagglutinin (PHA)-binding sites were histochemically investigated in normal adult skin and various skin tumors using peroxidase-labeled lectin. In the normal skin, acrosyringium and distal portion of intradermal duct of eccrine and apocrine sweat glands were intensely stained with PHA. Other elements of the skin were virtually negative. Among various kinds of sweat gland tumors and other skin tumors, syringoma and eccrine porocarcinoma were intensely stained with PHA. Small ductal structures of nodular hidradenoma and mixed tumor of the skin were also stained with PHA. No other skin tumors were positive with PHA staining. The present study clearly showed that PHA is a useful histochemical marker of distal portion of eccrine and apocrine sweat ducts.