Chapter 39: Ovarian Cancer

KEY CONCEPTS

• Over the past decade, there has been increasing recognition that epithelial ovarian cancers (EOCs) represent a heterogeneous group of malignancies secondary to distinct pathogenic pathways and molecular alterations associated with the development of different histologic subtypes. Although some types are thought to arise from the ovarian surface epithelium, the fallopian tube is the likely origin of high-grade serous cancer. This understanding heralded the practice of risk-reducing salpingo-oophorectomy in women at high risk for development of ovarian cancer

• Stage of disease at the time of diagnosis is an important prognostic indicator. Five-year survival rates among women with localized, regional, and distant disease at the time of diagnosis are 92%, 72%, and 27%, respectively. Early-stage ovarian cancer is discovered in fewer than 30% of patients.

• In advanced EOC, surgery and chemotherapy are both used in initial management; however, there remains debate regarding the sequence of these interventions. Historically, patients have been candidates for neoadjuvant chemotherapy if they have multiple medical comorbidities, poor performance status, or extensive disease on imaging that is not felt to be amenable to upfront surgery. Despite this, there is no current consensus regarding which patients should have upfront cytoreduction or neoadjuvant chemotherapy.

• High risk of recurrent disease after treatment of advanced-stage EOC has prompted an intensive search for maintenance strategies, and poly (adenosine diphosphate [ADP]-ribose) polymerase inhibitors have been found to be particularly efficacious in this setting. Recent trials have yielded multiple indications: olaparib for patients with germline or somatic BRCA1/2 mutations, niraparib for all-comers, and the combination of olaparib and bevacizumab for those with homologous-recombination deficiency.

• Over the last 5 years, a number of trials have assessed the efficacy of programmed cell death protein 1/programmed cell death ligand 1 immune checkpoint inhibitors in patients with recurrent EOC. The efficacy results can be summarized as an observed response rate of 10% to 15%, with another 20% to 40% of patients experiencing stable disease.

• Malignant ovarian germ cell tumors (MOGCTs) recapitulate normal embryonic and extraembryonic cells and structures and are derived from the primitive germ cells of the embryonic gonad. The MOGCTs comprise 2% to 3% of all ovarian malignancies, and they usually develop in girls, adolescents, and women of reproductive age. Advances in chemotherapy have yielded cure in the vast majority of patients with these tumors, and modifications in surgical technique have allowed fertility preservation in most patients.