Cost-effectiveness studies on cervical cancer.

Cost-effectiveness analyses are an important source of information for the design and evaluation of policies to reduce cervical cancer. This paper describes the recommendations of a panel on cost-effectiveness studies convened as part of the International Consensus Conference on the Fight Against Cervical Cancer. Recommendations for cost-effectiveness studies include: (1) the use of reference case methods to support comparisons across studies, (2) the use of a consistent standard of evidence on the clinical effectiveness of different screening strategies, (3)further research into the costs and effectiveness of different screening and treatment strategies for cervical cancer, (4) further research into screening and treatment strategies in a wide range of countries, (5) easily accessible and detailed descriptions of the methods and supplementary analyses underlying published studies, (6) greater use of newly developed models of cervical cancer, and (7) greater revelation of potential conflict of interest by researchers.

De novo establishment and cost-effectiveness of Papanicolaou cytology screening services in the Socialist Republic of Vietnam.

BACKGROUND: Cervical carcinoma is the leading cause of cancer-related death among women in the developing world. The absence of cervical screening in Vietnam and other developing countries is due in large part to the perceived expense of implementing Papanicolaou cytology screening services, although, to the authors' knowledge, the cost-effectiveness of establishing such services has never been studied in a developing country. METHODS: Using decision analytic methods, the authors assessed cost-effectiveness of Pap screening from a societal perspective in Vietnam, the world's 9th most populous developing country (estimated 1999 population, 79 million). Outcomes measured included life expectancy, cervical carcinoma incidence, cost per woman, and cost-effectiveness. RESULTS: Total costs to establish a nationwide 5-year interval Pap screening program in Vietnam will average less than $148,400 annually during the 10-year time period assumed necessary to develop the program and may be considerably lower if only high risk geographic areas are targeted. Maintenance costs will average less than $0.092 annually per woman in the target screening population. Assuming 70% program participation, cervical carcinoma incidence will decrease from 26 in 100,000 to 14.8 in 100,000, and cost-effectiveness will be $725 per discounted life-year. Several assumptions used in this analysis constitute biases against the effectiveness of Pap screening, which in reality may be significantly more cost-effective than reported here. CONCLUSIONS: Contrary to widespread belief, Pap screening in developing countries such as Vietnam is extraordinarily inexpensive and appears to be cost-effective. Because prospects are uncertain regarding useful alternatives to the Pap test, the evidence-based argument for establishing conventional Pap screening services in developing countries such as Vietnam is compelling. Population-based conventional Pap screening services have been established de novo in Vietnam and are now operational.

Immunologic analysis of human breast cancer progesterone receptors. 1. Immunoaffinity purification of transformed receptors and production of monoclonal antibodies.

A monoclonal antibody (MAb), designated PR-6, produced against chick oviduct progesterone receptors [Sullivan, W. P., Beito, T. G., Proper, J., Krco, C. J., & Toft, D. O. (1986) Endocrinology (Baltimore) 119, 1549-1557] cross-reacts with the Mr 120,000 human B receptors. An immunomatrix prepared with PR-6 was used to purify progesterone receptors (PR) from T47D human breast cancer cells. Single-step immunoaffinity chromatography results in enrichment of B receptors (identified by immunoblot with PR-6 and by photoaffinity labeling with [3H]promegestone) to a specific activity of 1915 pmol/mg of protein (or 23% purity) and with 27% yield. Purity and yields as judged by gel electrophoresis and densitometric scanning of the B protein were approximately 1.7-fold higher due to partial loss in hormone binding activity at the elution step. A second purification step by diethylaminoethyl chromatography gives further enrichment to 3720 pmol/mg of protein (or 44% purity) to yield essentially two proteins, 120-kilodalton (kDa) B receptors and a 76-kDa non-steroid binding protein, each in approximately equivalent amounts. B receptors purified under these conditions are transformed and biologically active. They were maintained as undegraded 120-kDa doublets and retained both hormone and DNA binding activities. Isolated B receptors were free of the 90-kDa non-steroid binding protein observed to be associated with 8S untransformed receptors in other systems and were free also of the non-hormone binding 105-108-kDa B antigen described previously to copurify with chick PR. These purified B receptors were used as immunogen for production of four monoclonal antibodies against human PR. Three of the MAbs, designated as B-30 (IgG1), B-64 (IgG1), and B-11 (IgM), are specific for B receptors. The fourth MAb, A/B-52 (IgG1), reacts with both A and B receptors. The IgG MAbs are monospecific for human PR since they recognize and absorb native receptor-hormone complexes, displace the sedimentation of 4S receptors on salt containing sucrose gradients, and, by immunoblot assay of crude T47D cytosol, react only with receptor polypeptides. Although mice were injected with B receptors only, production of A/B-52 which recognized both A and B receptors provides evidence that these two proteins share regions of structural homology. These new MAbs are valuable reagents for further studies of human receptor structure and function and for clinical immunodetection of PR in breast tumors.

The tiny parathyroid adenoma.

In the past 11 years we have operated on three patients with "tiny" parathyroid adenomas (less than 60 mg). Two of these adenomas were virtually indistinguishable visually from the normal glands. (The third adenoma was found only after fixation and permanent sections.) Despite frozen-section diagnoses of "probable hyperplastic tissue" in two cases, these small hyperplastic glands proved confusing at operation. This was especially true of the hyperactive gland embedded within mediastinal tissue that, on initial examination of gross material, had been missed by surgeons and pathologists alike and was discovered only on permanent serial sections. The preoperative laboratory data did not vary substantially from that of other hyperparathyroid patients with larger adenomas; in each case two or more endocrinologists had agreed that parathyroidectomy was indicated and had referred these patients for operation. Permanent microscopic sections confirmed the diagnosis of parathyroid adenoma in all three patients. The clinical and laboratory postoperative data strongly indicate that these small adenomas, masquerading as normal-sized glands, were responsible for the hypercalcemia. These tiny adenomas should be added to the other anatomic and pathologic variations of the parathyroid glands that can prove confusing at operation.