ABSTRACT
OBJECTIVE: To produce a set of three reference materials that mimic sera from patients with prostate disorders in the prostate-specific antigen (PSA) concentration range important for clinical screening for prostate cancer (approximately 0.5, approximately 4.0, and approximately 10.0 ng/mL), to analyze these reference materials in a large number of clinical laboratories using a variety of commercially available methods, and to characterize the molecular forms of PSA in them. METHODS: Units of serum from healthy individuals and from patients with varying degrees of elevated PSA were pooled, lyophilized, and distributed along with conventionally prepared, semen-supplemented proficiency testing samples to laboratories participating in the College of American Pathologists Basic Ligand Survey. The reference material and one of the standard Survey samples were fractionated by Sephacryl S-200-HR gel filtration chromatography. RESULTS: The Abbott IMx, Hybritech Tandem-E, Hybritech Tandem-R, and Tosoh AIA-Pack all measured PSA in the reference material fairly equally (agreement within +/- 12%). In contrast, the Abbott IMx results in the semen-supplemented Survey specimens were as much as 1.8-fold higher than the other three assays. Characterization of the molecular forms showed the reference material was approximately 90% alpha 1-antichymotrypsin-bound PSA, whereas the semen-supplemented Survey specimens were approximately 40% alpha 1-antichymotrypsin-bound PSA, which largely explained the difference in assay recoveries. CONCLUSIONS: Semen-free materials containing only endogenous PSA much more closely mimic real clinical specimens and should prove useful in efforts to standardize clinical PSA assays.
Subject(s)
Prostate-Specific Antigen/standards , Blood/immunology , Chromatography, Gel , Humans , Immunoassay , Male , Prostate-Specific Antigen/analysis , Prostate-Specific Antigen/isolation & purification , Prostatic Neoplasms/diagnosis , Reference Standards , Semen/immunology , alpha 1-Antichymotrypsin/analysisABSTRACT
An elderly man with a retrovesical leiomyosarcoma is described. This unusual tumor showed a prominent myxoid stroma. The smooth muscle origin of the malignant spindle cells was confirmed by ultrastructural study. Review of the literature has not yielded a similar case.
Subject(s)
Leiomyosarcoma/pathology , Urinary Bladder Neoplasms/pathology , Aged , Humans , Leiomyosarcoma/ultrastructure , Male , Urinary Bladder Neoplasms/ultrastructureABSTRACT
Ureteral obstruction secondary to endometriosis is an infrequently observed phenomenon, particularly in post-menopausal women. Two patients with obstructive uropathy, aged fifty-five and seventy-four, underwent ureteroplasty procedures with pathologic documentation of endometriosis. The possible pathogenetic mechanisms of ureteral endometriosis and previously reported cases are cited.