PGR and melanoma: All other markers tested were negative (pan-melanoma, HMB45, Melan A, keratin AE1/AE3, desmin, alpha smooth muscle actin, h-caldesmon, CD34, p16, CD117, DOG1, myogenin, CD10, estrogen receptor (ER), progesterone receptor (PR), PAX8, WT1, synaptophysin, chromogranin A, CD99 and PRAME)).