PECAM1 and medullary thyroid gland carcinoma: Pilot staining of 50 samples with variable PSMA expression including FA (n = 5), FTC (n = 10), PTC (n = 25), PDTC (n = 4), ATC (n = 3), and medullary thyroid carcinoma (MTC; n = 3) with CD31/CD34 and further matching, demonstrated that PSMA was not ubiquitously expressed in tumor microvasculature.