Immunohistochemical determination of c-myc, c-erb-B2, nm23 and p53 expression in archival, paraffin-embedded pathological samples were used from patients operated upon for pelvic endometriosis. c-myc was expressed in 8/15 cases (53.3%). nm23 was expressed in 7/16 cases (43.7%). c-erb-B2 and p53 reactivity was undetectable in the samples studied.