Hereditary Ovarian Carcinoma

Efficient screening for ovarian cancers using a combination of tumor markers CA602 and CA546

A new efficient screening for ovarian cancer based on a combination of two tumor markers, CA602 and CA546, is reported. These two tumor markers can be detected by a combination immunoenzymometric assay of these two antigens. This combination assay was initially performed in 1189 patients with clinically detected ovarian tumors (final pathological diagnosis: 645 cases of benign disease and 544 cases of malignant disease), and benign disease included 122 patients with endometriosis and 523 normal healthy women. The combination of CA602 and CA546 increased the detection rate of ovarian cancer from 77.8 to 85.8% compared with CA602 alone, demonstrating that the combination assay was effective at detecting ovarian cancers. The combination assay of CA602 and CA546 was then applied to 21,374 random subjects to screen for asymptomatic ovarian cancer. Ovarian cancer was detected in nine patients (detection rate: 0.04%), of which four cases were stage I disease. A retrospective analysis of these four patients revealed that a screening based on only a single assay would have been negative and further reiterates the effectiveness of this combination assay in detecting potential disease.

Potential for TRAIL as a Therapeutic Agent in Ovarian Cancer

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is known to induce apoptosis, otherwise known as programmed cell death, in many malignant cells without any known detrimental effects to normal cells. These aspects of TRAIL indicate the potential of TRAIL as a therapeutic agent in cancer. Ovarian cancer remains the deadliest gynecologic malignancy and is the fourth leading cause of death due to cancer in women. However, it has been shown in studies that ovarian cancer cells are sensitive to TRAIL-induced cell death when treated with TRAIL alone or in combination with chemotherapeutic agents. TRAIL signals through two death receptors, TRAIL-R1 and TRAIL-R2, to induce apoptosis. TRAIL also binds to two other cell surface receptors, TRAIL-R3 and TRAIL-R4, which do not have intracellular death domains and therefore do not transmit the apoptotic signal upon ligation with TRAIL. It has been shown that a chemokine, interleukin-8 (IL-8), may play a role in ovarian tumor progression due to its elevated presence in the fluid surrounding ovarian cancer tissues. Possible roles for IL-8 in ovarian tumorigenesis include angiogenesis and metastasis. Because the mechanism of regulation for TRAIL-induced apoptosis needs to be clarified, the role of IL-8 in TRAIL-induced apoptosis of ovarian cancer cells was studied. Results showed that the presence of IL-8 regulates cell-surface expression of TRAIL receptors in ovarian cancer cell lines in vitro. There may be a role for the p38 mitogen-activated protein kinase (MAPK) pathway in TRAIL-induced apoptosis of ovarian cancer cell.

Risk assessment & genetic testing

Ovarian cancer is the fifth most common cause of cancer death in women in Western countries and family history is one of the strongest known risk factors. Approximately 5 to 13% of all ovarian cancer cases are caused by the inheritance of cancer predisposing genes with an autosomal pattern of transmission. The inherited fraction of ovarian cancer may differ between populations. Based on analysis of familial ovarian cancer pedigrees and other epidemiological studies, three hereditary ovarian cancer syndromes have been defined. The identification of the genes responsible for most hereditary ovarian cancers has open a new area of early detection methods and preventive procedures specifically dedicated to women identified as carrying ovarian cancer predisposing genes. Predictive oncology is best performed by a dedicated unit with professionals aware of all the issues surrounding genetic testing.

Ovarian cancer. Current outlook on this deadly disease

The lifetime risk of ovarian cancer in the US population is about 1.4%. The risk is increased in women who have a strong family history of the disease. Unfortunately, no accurate screening tests are available. Transvaginal sonography and CA-125 determinations can be valuable in selected patients. Attempts at prevention with oral contraceptive use and indicated or prophylactic oophorectomy should be seriously considered. Conservative treatment is appropriate in selected patients with early-stage ovarian cancer. However, because the majority of patients present with advanced disease, maximum cytoreductive surgery followed by chemotherapy is usually required. Such an approach results in a high incidence of initial clinical remission and can prolong survival to 2 or 3 years. Eventually, however, relapse and death often occur in spite of additional therapy. Another operation may be needed for secondary cytoreduction or palliation. Bowel obstruction, recurrent ascites, and pleural effusion are often terminal events.

Autonomy of the epithelial phenotype in human ovarian surface epithelium: changes with neoplastic progression and with a family history of ovarian cancer

Epithelial ovarian carcinomas originate in the ovarian surface epithelium (OSE). In culture, OSE undergoes epithelio-mesenchymal conversion, an event mimicking a wound response, while ovarian carcinomas retain complex epithelial characteristics. To define the onset of this increased epithelial autonomy in ovarian neoplastic progression, we examined mesenchymal conversion in OSE from 25 women with no family histories (NFH-OSE) and 13 women with family histories (FH-OSE) of breast/ovarian cancer (including 8 with mutated BRCA1 or 17q linkage) and in 8 ovarian cancer lines. After 3-6 passages in monolayer culture, most NFH-OSE exhibited reduced keratin expression and high collagen type III expression. In contrast, keratin remained high but collagen expression was lower in p. 3-6 FH-OSE. This difference was lost in SV40-transformed lines, which all resembled FH-OSE. Most carcinoma lines remained epithelial and did not undergo mesenchymal conversion. In 3-dimensional (3-D) sponge culture, NFH-OSE cells dispersed and secreted abundant extracellular matrix (ECM). FH-OSE remained epithelial and did not secrete ECM. ECM production was also reduced in SV40-transformed lines. Carcinoma lines in 3-D formed epithelial cysts, aggregates and papillae and lacked ECM. Sponge contraction (a mesenchymal characteristic) was greater in NFH-OSE than in FH-OSE both before and after SV40 transformation and was absent in the cancer lines. Our results suggest that increased autonomy of epithelial characteristics is an early indicator of ovarian neoplastic progression and that phenotypic changes indicative of such autonomy are found already in overtly normal OSE from women with histories of familial breast/ovarian cancer.

Family history in ovarian cancer referral population

In order to determine the incidence of familial and hereditary ovarian cancer in a referral patient population, we conducted a retrospective study of 44 patients from a consecutive set of 62 patients treated for ovarian carcinoma at the Gynecologic Oncology Clinic at the Richland Memorial Hospital Center for Cancer Treatment and Research between January 1, 1993 and December 31, 1993. In our study of the referred patients, only two (4.55%) reported a history of at least one first-degree relative also being affected with ovarian cancer. However, 13 patients (29.55%) reported a family history consistent with one of the hereditary ovarian cancer syndromes. In addition to having a suggestive family history, these 13 families demonstrated several cardinal features of hereditary cancer syndromes including early onset, bilaterality, multiple primary tumors, and transmission. Race was the only significantly different demographic factor between the hereditary and sporadic ovarian cancer groups. All 13 patients who appeared to have a hereditary form of cancer were Caucasian.

Increased risk of second primary malignancies in patients with gynecological cancer. A Swedish record-linkage study

The Stockholm-Gotland Cancer Register was used to study the risk of developing second primary malignancies (SPM) in women diagnosed with cancer of the uterine cervix, uterine corpus and ovaries during the period 1958-1992. Among 5,325 patients with uterine cervix cancer, 619 developed SPM. Standardized incidence ratio (SIR) was 1.29 (95% confidence interval (CI) 1.19-1.39). Significantly increased risks were observed for cancer of the colon, rectum, lung, vulva, kidney and bladder. A total of 4,815 women with uterine corpus cancer were followed and 660 SPM were found. The overall SIR was 1.21 (95% CI 1.12-1.30) with significantly increased risk for cancer of the colon, ovary, vulva and bladder. The incidence of leukemia was also significantly elevated (SIR = 3.03; 95% CI 1.70-5.00). Among 5,060 patients with ovarian cancer, 379 SPM were found (SIR 1.49; 95% CI 1.34-1.64). Increased risks of cancer of the colon, rectum, breast, uterine corpus, bladder and leukemia were observed. All three primary sites showed elevated risks of cancer of the colon and bladder. For patients with a primary cancer of the corpus and ovary an elevated risk of leukemia was also noted. The conclusion from these findings is that SPM to some extent can be explained by previously known factors, i.e. treatment and common risk factors. However, further studies concerning the role of common etiology, for instance hereditary and hormonal factors, are needed to increase the knowledge on the etiology of second primary malignancies.