Response and Survival in Patients With Progressive or Recurrent Serous Ovarian Tumors of Low Malignant Potential

Early Events in the Pathogenesis of Epithelial Ovarian Cancer

Ovarian carcinogenesis, as in most cancers, involves multiple genetic alterations. A great deal has been learned about proteins and pathways important in the early stages of malignant transformation and metastasis, as derived from studies of individual tumors, microarray data, animal models, and inherited disorders that confer susceptibility. However, a full understanding of the earliest recognizable events in epithelial ovarian carcinogenesis is limited by the lack of a well-defined premalignant state common to all ovarian subtypes and by the paucity of data from early-stage cancers. Evidence suggests that ovarian cancers can progress both through a stepwise mutation process (low-grade pathway) and through greater genetic instability that leads to rapid metastasis without an identifiable precursor lesion (high-grade pathway). In this review, we discuss many of the genetic and molecular disorders in each key process that is altered in cancer cells, and we present a model of ovarian pathogenesis that incorporates the role of tumor cell mutations and factors in the host microenvironment important to tumor initiation and progression.

Management of borderline ovarian neoplasms

Over the last decades, the management of borderline ovarian tumors (BOTs) has changed from radical surgery to more conservative therapy as a result of the need for fertility-sparing surgery and the increasing use of laparoscopy. The question is whether this is good clinical practice from an oncologic point of view. Here, recent literature regarding management of borderline ovarian neoplasms is reviewed, and oncologic concerns are discussed with emphasis on the mode of surgery and the possibility of fertility-sparing surgery and its consequences. Proper staging is defined as an exploration of the entire abdominal cavity with peritoneal washings, infracolic omentectomy, and multiple peritoneal biopsies as the cornerstone of a successful treatment, and this is only possible through a midline incision. For stage I disease, conservative surgery consisting of unilateral salpingo-oophorectomy or cystectomy in case of bilateral ovarian involvement or when the disease develops in the only remaining ovary is a valuable alternative in a number of young patients who want to preserve their fertility. Patients with advanced-stage disease or who are finished childbearing are treated with radical surgery consisting of peritoneal washings, total abdominal hysterectomy, bilateral salpingo-oophorectomy, infracolic omentectomy, complete peritoneal resection of macroscopic lesions, or multiple peritoneal biopsies; in case of mucinous BOTs, patients also are treated with an appendectomy.

Expression profiling of serous low malignant potential, low-grade, and high-grade tumors of the ovary

Papillary serous low malignant potential (LMP) tumors are characterized by malignant features and metastatic potential yet display a benign clinical course. The role of LMP tumors in the development of invasive epithelial cancer of the ovary is not clearly defined. The aim of this study is to determine the relationships among LMP tumors and invasive ovarian cancers and identify genes contributing to their phenotypes. Affymetrix U133 Plus 2.0 microarrays (Santa Clara, CA) were used to interrogate 80 microdissected serous LMP tumors and invasive ovarian malignancies along with 10 ovarian surface epithelium (OSE) brushings. Gene expression profiles for each tumor class were used to complete unsupervised hierarchical clustering analyses and identify differentially expressed genes contributing to these associations. Unsupervised hierarchical clustering analysis revealed a distinct separation between clusters containing borderline and high-grade lesions. The majority of low-grade tumors clustered with LMP tumors. Comparing OSE with high-grade and LMP expression profiles revealed enhanced expression of genes linked to cell proliferation, chromosomal instability, and epigenetic silencing in high-grade cancers, whereas LMP tumors displayed activated p53 signaling. The expression profiles of LMP, low-grade, and high-grade papillary serous ovarian carcinomas suggest that LMP tumors are distinct from high-grade cancers; however, they are remarkably similar to low-grade cancers. Prominent expression of p53 pathway members may play an important role in the LMP tumor phenotype.