Ross S. Berkowitz

A Radioimmunoassay Using a Monoclonal Antibody to Monitor the Course of Epithelial Ovarian Cancer

The murine monoclonal antibody OC 125 reacts with an antigen (CA 125) common to most nonmucinous epithelial ovarian carcinomas. An assay has been developed to detect CA 125 in serum. By this assay, only 1 per cent of 888 apparently healthy persons and 6 per cent of 143 patients with nonmalignant disease had serum CA 125 levels above 35 U per milliliter. In contrast, 83 of 101 patients (82 per cent) with surgically demonstrated ovarian carcinoma had elevated levels of antigen. In 38 patients with epithelial ovarian carcinoma monitored on 2 to 18 occasions during 2 to 60 months, antigen levels ranged from less than 1 to more than 8000 U per milliliter. Rising or falling levels of CA 125 correlated with progression or regression of disease in 42 of 45 instances (93 per cent). Determination of CA 125 levels may aid in monitoring the response to treatment in patients with epithelial ovarian cancer.

Intraepithelial carcinoma of the fimbria and pelvic serous carcinoma: Evidence for a causal relationship.

Proposed origins of pelvic serous carcinoma include the ovary, fallopian tube, and peritoneum. Prophylactic salpingo-oophorectomies in BRCA+ women have recently identified the fimbria as a site of origin for early serous carcinoma (tubal intraepithelial carcinoma or TIC). We explored the relationship of TIC to pelvic serous carcinomas in consecutive cases with complete adnexal exam (SEE-FIM protocol). Cases positive (group A) or negative (group B) for endosalpinx (including fimbria) involvement, were subclassified as tubal, ovarian, or primary peritoneal in origin. Coexisting TIC was recorded in group A when present and p53 mutation status was determined in 5 cases. Of 55 evaluable cases, 41 (75%) were in group A; including tubal (n=5), peritoneal (n=6), and ovarian (n=30) carcinomas. Foci of TIC were identified in 5 of 5, 4 of 6, and 20 of 30, respectively. Ninety-three percent of TICs involved the fimbriae. Five of 5 TICs and concurrent ovarian carcinomas contained identical p53 mutations. Thirteen of 14 cases in group B were classified as primary ovarian carcinomas, 10 with features supporting an origin in the ovary. Overall, 71% and 48% of “ovarian” serous carcinomas had endosalpinx involvement or TIC. TIC coexists with all forms of pelvic serous carcinoma and is a plausible origin for many of these tumors. Further studies are needed to elucidate the etiologic significance of TIC in pelvic serous carcinoma, reevaluate the criteria for tubal, peritoneal, and ovarian serous carcinoma, and define the role of the distal tube in pelvic serous carcinogenesis.

Gestational Trophoblastic Disease.

Gestational trophoblastic disease encompasses a range of pregnancy-related disorders, consisting of the premalignant disorders of complete and partial hydatidiform mole, and the malignant disorders of invasive mole, choriocarcinoma, and the rare placental-site trophoblastic tumour. These malignant forms are termed gestational trophoblastic tumours or neoplasia. Improvements in management and follow-up protocols mean that overall cure rates can exceed 98% with fertility retention, whereas most women would have died from malignant disease 60 years ago. This success can be explained by the development of effective treatments, the use of human chorionic gonadotropin as a biomarker, and centralisation of care. We summarise strategies for management of gestational trophoblastic disease and address some of the controversies and future research directions.

Primary Fallopian Tube Malignancies in BRCA-Positive Women Undergoing Surgery for Ovarian Cancer Risk Reduction

PURPOSE To review the frequency and location of malignancies detected after prophylactic salpingo-oophorectomy in women with BRCA mutations. METHODS Medical records and pathology findings were reviewed from BRCA-positive women undergoing prophylactic surgery for ovarian cancer risk reduction who underwent complete examination of the adnexa. Patients undergoing this procedure between January 1999 and January 2007 were identified. RESULTS From January 1999 to January 2007, 122 BRCA-positive patients underwent prophylactic surgery in the Division of Gynecologic Oncology at Brigham and Womens Hospital. The median age was 46.5 years (range, 33 to 76 years). Seven (5.7%) were found to have an early malignancy in the upper genital tract and all patients were age > or = 44 years at diagnosis. Of seven consecutive cancers culled between January 1999 and January 2007, all (100%) originated in the fimbrial or ampullary region of the tube; six had an early (intraepithelial) component. Two were associated with surface implants on the ovary and two required repeated sectioning to detect microscopic carcinomas in the fimbria. CONCLUSION The distal fallopian tube seems to be the dominant site of origin for early malignancies detected in approximately 6% of women undergoing ovarian cancer risk-reduction surgery. The greatest proportion of serous cancer risk in BRCA mutation-positive women should be assigned to the fimbria rather than the ovary, and future clinical and research protocols should employ thorough examination of the fimbria, including multiple sections from each tissue block, to maximize detection of early malignancies in this population.

SPARC (Secreted Protein Acidic and Rich in Cysteine) Induces Apoptosis in Ovarian Cancer Cells

Secreted protein acidic and rich in cysteine (SPARC) is an extracellular Ca(2+)-binding matricellular glycoprotein that associates with cell populations undergoing migration, morphogenesis, and differentiation. Studies on endothelial cells have established that its principal functions in vitro are counteradhesion and antiproliferation. The mechanism(s) underlying these antitumor effects is unknown. In this study, we showed that SPARC expression in ovarian cancer cells is inversely correlated with the degree of malignancy. The immunohistochemical data presented here confirmed the importance of diminished SPARC expression in ovarian cancer development. Treating human ovarian surface epithelial cells and ovarian cancer cells with SPARC revealed that as SPARC inhibits the proliferation of both normal and cancer cells, it induces apoptosis only in cancer cells. This observation indicates that down-regulation of SPARC is essential for ovarian carcinogenesis as cancer cells become sensitized to the apoptotic activity of SPARC during malignant transformation. We also showed here the first direct evidence that putative SPARC receptors are present on ovarian epithelial cells. Their levels are higher in human ovarian surface epithelial cells than cancer cells. Binding of SPARC to its receptor is likely to trigger tissue-specific signaling pathways that mediate its tumor suppressing functions. Decrease in ligand-receptor interaction by the down-regulation of SPARC and/or its receptor is essential for ovarian carcinogenesis.

Targeting Notch, a key pathway for ovarian cancer stem cells, sensitizes tumors to platinum therapy

Chemoresistance to platinum therapy is a major obstacle that needs to be overcome in the treatment of ovarian cancer patients. The high rates and patterns of therapeutic failure seen in patients are consistent with a steady accumulation of drug-resistant cancer stem cells (CSCs). This study demonstrates that the Notch signaling pathway and Notch3 in particular are critical for the regulation of CSCs and tumor resistance to platinum. We show that Notch3 overexpression in tumor cells results in expansion of CSCs and increased platinum chemoresistance. In contrast, γ-secretase inhibitor (GSI), a Notch pathway inhibitor, depletes CSCs and increases tumor sensitivity to platinum. Similarly, a Notch3 siRNA knockdown increases the response to platinum therapy, further demonstrating that modulation of tumor chemosensitivity by GSI is Notch specific. Most importantly, the cisplatin/GSI combination is the only treatment that effectively eliminates both CSCs and the bulk of tumor cells, indicating that a dual combination targeting both populations is needed for tumor eradication. In addition, we found that the cisplatin/GSI combination therapy has a synergistic cytotoxic effect in Notch-dependent tumor cells by enhancing the DNA-damage response, G2/M cell-cycle arrest, and apoptosis. Based on these results, we conclude that targeting the Notch pathway could significantly increase tumor sensitivity to platinum therapy. Our study suggests important clinical applications for targeting Notch as part of novel treatment strategies upon diagnosis of ovarian cancer and at recurrence. Both platinum-resistant and platinum-sensitive relapses may benefit from such an approach as clinical data suggest that all relapses after platinum therapy are increasingly platinum resistant.

Occult Ovarian Tumors in Women With BRCA1 or BRCA2 Mutations Undergoing Prophylactic Oophorectomy

PURPOSE To review the findings at prophylactic oophorectomy of a series of women who presented to a familial breast and ovarian cancer clinic. MATERIALS AND METHODS Data from medical charts, operative notes, and pathology reports were collected on women who had undergone prophylactic oophorectomies because of the elevated risk of ovarian cancer. Because only a subset of patients underwent BRCA1 and BRCA2 testing, each patients risk of hereditary predisposition was calculated using the Berry-Parmigiani model and family history data. RESULTS From June 1989 to December 1998, 50 women seen at our clinic underwent prophylactic oophorectomy, 33 of whom had a calculated risk of carrying a germline BRCA1 or BRCA2 mutation greater than 25%. Among this group, four incidental tumors were found (four of 33, or 12%); one tumor was noted at the time of surgery and three were noted only in the final pathology. Two patients had microscopic, poorly differentiated serous adenocarcinomas in multiple sites on both ovaries. A third patient had a bilateral serous borderline tumor with micropapillary features. The fourth patient had a microscopic serous borderline ovarian tumor. All four patients had germline BRCA1 or BRCA2 mutations, and three had unremarkable transvaginal ultrasonography examinations within 6 months before prophylactic surgery. CONCLUSION Foci of malignant tumor are not uncommon in prophylactic oophorectomies performed in women at very high risk for ovarian cancer and may not be detected on ultrasonograms. Surgeons should have a high suspicion of finding cancer in these women at the time of prophylactic surgery, and careful pathologic assessment of the specimens should be conducted.

DOC-2, a candidate tumor suppressor gene in human epithelial ovarian cancer

Using RNA fingerprinting (RAP) strategy and Northern blot analysis, we identified a differentially expressed sequence DOC-2 which is detectable in all normal human ovarian surface epithelial (HOSE) cell cultures but not in ovarian cancer cell lines and tissues. Subsequent cloning of DOC-2 from a cDNA library generated from the HOSE cells was carried out using the 3′ and 5′ RACE approach. A 3268 base pair full length cDNA of DOC-2 was isolated and sequenced. The predicted protein has a length of 770 amino acids. Homology search of all NCBI sequences indicated that the amino acid sequence of DOC-2 shares 93% homology with the mouse p96/mDab2 phosphoprotein and has a phosphotyrosine interacting domain (PID) and multiple SH3 binding motifs. Chromosomal localization by FISH showed that the DOC-2 gene is located on 5p13. Western blot analysis showed that the 105 kDa DOC-2 protein was down-regulated in all the carcinoma cell lines. In-situ immunohistochemistry performed on normal ovaries, and benign, borderline and invasive ovarian tumor tissues showed down regulation of DOC-2 protein particularly in serous ovarian tumor tissues. When DOC-2 was transfected into the ovarian carcinoma cell line SKOV3, the stable transfectants showed significantly reduced growth rate and ability to form tumors in nude mice. These data suggest that down-regulation of DOC-2 may play an important role in ovarian carcinogenesis.

The changing clinical presentation of complete molar pregnancy

Objective To determine if the clinical presentation of complete hydatidiform mole has changed in recent years compared with historic controls (1965–1975). Methods Chart review of all 74 patients referred to the New England Trophoblastic Disease Center for the primary management of complete hydatidiform mole during 1988–1993 was performed and comparison made to historic controls (1965–1975). Results Vaginal bleeding remained the most common presenting symptom, occurring in 62 of 74 (84%) current patients, compared with 297 of 306 (97%) controls (P = .001). However, anemia was present in only four of 74 (5%) current patients, compared with 165 of 306 (54%) controls (P = .001). Excessive uterine size, preeclampsia, and hyperemesis occurred in only 21 of 74 (28%), one of 74 (1.3%), and six of 74 (8%) current patients, respectively, compared with 156 of 306 (51%), 83 of 306 (27%), and 80 of 306 (26%), respectively, of historic controls (P = .001). No cases of clinical hyperthyroidism or respiratory distress were found in recent years. Ultrasound diagnosed complete hydatidiform mole before the onset of clinical symptoms in seven of 69 (10%) current patients. Among patients not receiving chemoprophylaxis, persistent gestational trophoblastic tumor developed in 23% of current patients and 18.6% of historic controls. Conclusion Fewer current patients with complete hydatidiform mole present with the traditional symptoms of complete hydatidiform mole (excessive uterine size, anemia, preeclampsia, hyperthyroidism, or hyperemesis) when compared with historic controls. However, there has been no statistically significant change in the development of persistent gestational trophoblastic tumor in current patients compared with historic controls.

Current management of gestational trophoblastic diseases

OBJECTIVES This review was undertaken to describe current understanding of the natural history of molar pregnancy and persistent gestational trophoblastic neoplasia (GTN) as well as recent advances in their management. MATERIALS AND METHODS Recent literature related to molar pregnancy and GTN was thoroughly analyzed to provide a comprehensive review of the current knowledge of their pathogenesis and treatment. RESULTS Studies in patients with familial recurrent molar pregnancy indicate that dysregulation of parentally imprinted genes is important in the pathogenesis of complete hydatidiform mole (CHM). CHM is now being diagnosed earlier in pregnancy in the first trimester changing the clinical presentation and making the histologic appearance more similar to partial hydatidiform mole (PHM) and hydropic abortion. While the classic presenting symptoms of CHM are less frequent, the risk of developing GTN remains unchanged. Flow cytometry and immunostaining for maternally-expressed genes are helpful in distinguishing early CHM from PHM or hydropic abortion. Patients with molar pregnancy have a low risk of developing persistent GTN after achieving even one non-detectable hCG level (hCG <5 mIU/ml). Patients with persistent low levels of hCG should undergo tests to determine if the hCG is real or phantom. If the hCG is real, then further tests should determine what percentage of the total hCG is hyperglycosylated hCG and free beta subunit to establish a proper diagnosis and institute appropriate management. Patients with non-metastatic GTN have a high remission rate with many different single-agent regimens including methotrexate and actinomycin D. Patients with high-risk metastatic GTN require aggressive combination chemotherapy in conjunction with surgery and radiation therapy to attain remission. After achieving remission, patients can generally expect normal reproduction in the future. CONCLUSION Our understanding of the natural history and management of molar pregnancy and GTN has advanced considerably in recent years. While most patients can anticipate a high cure rate, efforts are still necessary to develop effective new second-line therapies for patients with drug-resistant disease.