Early detection: evaluation of an at-risk population to identify 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, asymptomatic population to identify a particular disease.
As of 2015, ovarian and endometrial cancers together accounted for over 24,000 deaths of American women yearly—approximately half as many deaths as breast cancer (Table 36-1). However, unlike breast cancer, there are no effective screening programs currently available and universally recommended to mitigate the morbidity and mortality associated with these cancers. In this chapter, we explore the possibilities and challenges for screening and early detection and discuss the role of sonographic techniques in providing early diagnosis of both ovarian and endometrial cancer. This will be followed by a discussion of each of these gynecologic cancers as related to their early detection with sonographic techniques alone and combined with other laboratory tests.
Table 36-1COMMON CANCERS IN WOMEN IN 2007 IN THE UNITED STATES ||Download (.pdf) Table 36-1 COMMON CANCERS IN WOMEN IN 2007 IN THE UNITED STATES
| ||Incidence ||Prevalence ||Mortality ||Screening Cancer Prevalence/1000 |
|Breast ||178,480 ||2,407,943 ||40,460 ||5.3 |
|Endometrial (uterine corpus) ||39,080 ||568,407 ||7,400 || |
|Ovarian ||22,430 ||172,765 ||15,280 ||0.31 |
|Cervix ||11,150 ||250,726 ||3,670 ||5.69 |
This chapter discusses and illustrates factors that influence the efficacy of screening and early detection schemes for ovarian and endometrial cancers that integrate transvaginal sonography (TVS) and related techniques such as color Doppler sonography (CDS), three-dimensional sonography (3DS), and contrast-enhanced TVS (CE-TVS) (Figure 36-1). The role of sonography in the evaluation of these two gynecologic cancers is considered together in this chapter because TVS can potentially detect both of these neoplasms in their earliest stages. TVS is probably best used in a multimodal scheme including certain lab tests such as CA-125 for the detection and evaluation of these gynecologic cancers. This chapter takes into account the recent advances in the understanding of the pathogenesis of these disorders and the use of biomarkers for their detection.
Principles of tumor detection with transvaginal color Doppler sonography (TV-CDS). A: Diagram of typical ovarian arterial and venous waveforms. The waveform will depend on whether it is obtained in an area of folliculogenesis or corpus luteum. In areas devoid of follicles the resistance is high; around a corpus luteum with its “vascular arcade,” the waveforms show low-resistance, high-diastolic flow. (Drawing used with permission from Paul Gross, MS.) B: Normal TV-CDS showing low-impedance flow in an intraovarian arteriole surrounding a functioning corpus luteum. C: Reconstructed 3D image of ovarian microvascularity. Note the regular branching pattern of the vessels within a normal ovary (left) when compared to the chaotic arrangement ...