Early detection: evaluation of individuals at risk for a particular disease.
"Lead time" bias: influence of time between diagnosis and onset of clinical disease.
"Length time" bias: influence of intrinsic growth rates on survivability.
Screening: evaluation of a nonselected population for a particular disease.
This chapter discusses and illustrates factors that influence the efficacy of screening and early detection schemes for ovarian and endometrial cancers using transvaginal sonography (TVS) and related techniques such as color Doppler sonography (CDS), three-dimensional sonography (3DS), and contrast-enhanced harmonic TVS (CE-TVS). The role of sonography in these 2 common gynecologic cancers is considered together in this chapter, because TVS can be used to evaluate both neoplasms. Sonography is probably best used in a multimodal scheme including certain lab tests for the detection and evaluation of these gynecologic cancers.1,2,3,4,5,6,7,8,9,10,11, and 12
Of these 2 cancers, TVS clearly has a greater potential role for early detection of early-stage ovarian cancer, which is difficult to detect by nonspecific or minimal symptomatology (as compared to advanced-stage disease with diffuse carcinomatosis) when compared to endometrial cancer, which is typically associated with postmenopausal uterine bleeding.
We present the potential role of TVS for the detection of both ovarian and endometrial cancer in this chapter to emphasize differences in their presentation, clinical course, and potential for earlier detection with sonographic techniques. Another reason to include discussion of these 2 common gynecologic cancers is the fact that there are recognizable TVS findings for the early stages of both ovarian and endometrial cancer. In addition, TVS can be used to evaluate both of these entities in the same patient. Admittedly, the potential lethality, prevalence, and clinical presentations of these 2 cancers are quite different.
In this chapter, identification of an appropriate screening population consisting of women at greatest risk for ovarian cancer by clinical history, CA-125, breast/ovarian cancer genetic analysis (BRCA1 and BRCA2), and proteomics is discussed. Women with risk factors for endometrial cancer such as obesity, diabetes, anovulation, polycystic ovarian syndrome, and hypertension are also excellent candidates to benefit from early detection.1,2 Used for this purpose, TVS has high negative predictive value but is limited by a relatively high false-positive rate.
Additional sonographic imaging using 3D- and/or contrast-enhanced sonographic techniques may improve early detection of ovarian cancer.13,14,15, and 16 These will be mentioned as they relate to improving screening efficacy, taking into consideration their incremental cost and requirements for increased technical expertise.
As of 2007 ovarian and endometrial cancers each accounted for over 22,000 deaths of American women yearly—approximately half as many deaths as breast cancer (Table 35-1). ...