Expression of cell cycle regulatory proteins in ovaries prophylactically removed from Jewish Ashkenazi BRCA1 and BRCA2 mutation carriers: Correlation with histopathology

Expression of p16 Tumor Suppressor Protein in Malignant Ovarian Germ Cell Tumors; Immunohistochemical Study

BACKGROUND

Malignant ovarian germ cell tumors represent small percentage of malignant ovarian neoplasms but they affect significantly young age group.

AIM OF THE STUDY

To investigate the immunohistochemical expression of p16 tumor suppressor protein in malignant ovarian germ cell tumors.

MATERIALS AND METHODS

Twenty-two malignant ovarian germ cell tumors (five dysgerminoma, eight immature teratoma, and nine yolk sac tumors), twenty mature cystic teratoma tumors and twenty normal ovarian tissue were immunohistochemically stained with p16 monoclonal antibody. Ki67 immunohistochemical staining was done for malignant ovarian germ cell tumors to assess proliferation.

RESULTS

We found that p16 tumor suppressor protein is overexpressed in all malignant ovarian germ cell tumors in both nuclear and cytoplasmic locations compared to control and to mature cystic teratoma (p-value <0.001). Cytoplasmic p16 expression was significantly correlated to Ki67 proliferation index in malignant ovarian germ cell tumors (p-value = 0.033, r = 0.445).

CONCLUSION

Overexpression of p16 in malignant ovarian germ cell tumors denotes that dysfunction of the cyclin dependent kinase pathway is involved in tumorigenesis of malignant ovarian germ cell tumors.

p53 signature and serous tubal in-situ carcinoma in cases of primary tubal and peritoneal carcinomas and serous borderline tumors of the ovary

The objective of this study was to evaluate the role of the fimbriated end and nonfimbriated epithelium of fallopian tubes with regard to p53 signature, tubal intraepithelial lesions in transition (TILT), and serous tubal in-situ carcinoma (STIC) in cases of different kinds of serous pelvic cancer. This study immunohistochemically evaluated (by Ki-67 and p53 staining) the presence of p53 signature, TILT lesions, and STIC in 14 consecutive cases of prophylactic salpingo-oophorectomy in women with BRCA-1/2 mutation (bilateral salpingo-oophorectomy), 11 cases of macroscopically inconspicuous adnexae of patients with primary contralateral tubal cancer (TC), 9 cases of primary peritoneal cancer (PPC), and 10 cases of serous ovarian borderline tumors, evaluating the fallopian tubes (using the Sectioning and Extensively Examining the FIMbria protocol), ovarian surface epithelium, and ovarian cortical inclusion cysts. The frequencies of p53 signature, TILT, and STIC were 35.7%, 7.1%, and 0% in cases of prophylactic surgery, 18.2%, 9.1%, and 18.2% in TC, and 11.1%, 0%, and 33.3% in PPC. These precursor lesions were missed during the initial routine screening and were found in the fimbriated end of the fallopian tubes in 94%. In 1 case of PPC, staining for p53 was negative in STIC. The studied adnexal tissue of serous ovarian borderline tumor and ovarian cortical inclusion cysts of all cases showed no alterations according to p53 signature, TILT, or STIC. STIC and p53 signature as precursor lesions of pelvic serous cancer were seen in macroscopically inconspicuous contralateral fallopian tubes in unilateral TC, in patients with elective bilateral salpingo-oophorectomy, and in patients affected by PPC. Therefore, we propose the complete processing of adnexal tissue and the use of step sectioning to establish the correct diagnosis. Immunohistochemistry for p53 and ki-67 may aid in the diagnosis, but is not necessary for routine investigation.

Microenvironment and pathogenesis of epithelial ovarian cancer

Multiple genetic alterations play a role in the pathogenesis of ovarian cancer. Although many key proteins and pathways involved in ovarian carcinogenesis and metastasis have been discovered, knowledge of the early steps leading to malignancy remains poorly understood. This poor understanding stems from lack of data from early-stage cancers and absence of a well-established premalignant state universal to all ovarian cancer subtypes. Existing evidence suggests that ovarian cancers develop either through a stepwise mutation process (low-grade pathway), through genetic instability resulting in hastened metastasis (high-grade pathway), or more recently through what has been described as the "'fimbrial-ovarian' serous neoplasia theory." In this latter model, ovarian serous cancers evolve from premalignant lesions in the distal fallopian tube called tubal intraepithelial carcinoma. In this manuscript, we review key genetic and molecular changes that occur in cancer cell progression and suggest a model of ovarian cancer pathogenesis involving both tumor cell mutations and microenvironmental factors.

A candidate precursor to pelvic serous cancer (p53 signature) and its prevalence in ovaries and fallopian tubes from women with BRCA mutations

BACKGROUND

Early serous carcinomas predominate in the fimbria of women with BRCA mutations (BRCA+). An entity in non-neoplastic mucosa sharing several properties of early serous carcinomas--the "p53 signature"--has been described in the distal fallopian tube and proposed as a precursor to serous carcinomas. This study compared the prevalence of p53 signatures in ovarian cortical inclusion cysts (CICs) and fallopian tubes from BRCA+ women and explored their relationship.

DESIGN

All tissues from 75 completely excised ovaries and tubes obtained during prophylactic surgery were studied by conventional microscopy, immunostaining for p53, and in selected cases, gamma-H2AX (DNA damage). P53 signatures were defined as 12 or more consecutive p53-positive secretory cell nuclei. Their prevalence in fallopian tubes and CICs was recorded, compared to an existing database of consecutive women without a suspicion of BRCA+ or ovarian cancer, and correlated with the number of CICs.

RESULTS

Tubal p53 signatures were detected in 29 of 75 cases (38%); 20 of 30 (66%) signatures examined were gamma-H2AX-positive. One ovary contained a small gamma-H2AX negative p53 signature on the ovarian surface; no p53 signatures were identified in CICs. The prevalence of BRCA+ p53 tubal signatures was similar to that of women with unknown BRCA status (38 v 33%). Presence of p53 signatures did not correlate with number of CICs.

CONCLUSIONS

p53 signatures were common in the fallopian tubes of BRCA+ women, were not identified in CICs, and did not correlate with the latter. The tubal p53 signature merits serious consideration as an important early event in serous carcinogenesis in BRCA+ women.

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.

Evaluation of normal-sized ovaries associated with primary peritoneal serous carcinoma for possible precursors of ovarian serous carcinoma

OBJECTIVE

Three groups of "high-risk" ovaries have previously been studied for possible precursors of ovarian carcinoma: ovaries removed prophylactically from women at high risk, normal ovaries contralateral to a unilateral ovarian carcinoma, and normal ovarian tissue found adjacent to primary ovarian carcinomas. No data are available for a fourth high-risk group: normal-sized ovaries from women with primary peritoneal serous carcinoma.

METHODS

Grossly normal-sized ovaries from 26 patients with primary peritoneal serous carcinoma were compared to normal-sized ovaries from 75 controls. Controls were divided at the median age for age matching. Cortical inclusions, surface epithelial invaginations (clefts), surface papillary proliferation, and calcifications were examined.

RESULTS

Case versus control comparisons showed, respectively, inclusions in 92% and 68% of patients, clefts in 54% and 59%, and papillomatosis in 35% and 16%. For each profile of ovary on one section, cases versus controls, respectively, had a mean number of inclusions of 5.55 and 3.97, size of the largest inclusion of 1.28 and 1.27 mm, and depth of the deepest cleft of 1.04 and 0.9 mm. After controlling for age, correcting for multiple comparisons and using two-sided chi square, there were no significant differences between cases and controls in all the parameters measured. In comparing the two control groups, the only significant finding was that the young group displayed deeper clefts than the older group (2.06 versus 0.9 mm, respectively).

CONCLUSION

Grossly normal-sized ovaries from women with primary peritoneal serous carcinoma display no significant differences in inclusions, clefts, papillomatosis, and calcifications in comparison to age-matched controls.

Congenital heart disease and pregnancy

Patients with congenital heart disease who wish to become pregnant offer a challenge to obstetricians, cardiologists and anesthetists. Although no large randomized trials exist to support the management of this emerging population, small prospective and retrospective studies provide valuable data on the likely success of pregnancy and the risks involved. Recently, there is emerging consensus on the management of this specialized group of patients, and this article aims to provide the practitioner with an overview of patient needs and the issues to be addressed. All patients with congenital heart disease wishing to consider pregnancy should be referred for specialist assessment prior to conception. Maternal risk, fetal risk and recurrence risk in the fetus should all be addressed. Most women with congenital heart disease can undergo pregnancy without significant risk. However, for some women the risk of maternal death is high, including those with: severe aortic stenosis, impaired left ventricular function, pulmonary hypertension and Marfan syndrome with dilated aortic root. All patients should be offered a detailed 20-week fetal cardiac scan and, in certain cases, prepregnancy genetic counseling. Most patients can deliver vaginally, with cesarean section reserved for obstetric indications or patients in whom straining at delivery could be potentially fatal (i.e., those with Marfan syndrome, aortic aneurysm, severe fixed left heart obstruction, or the acutely unwell mother). Antibiotic prophylaxis should be given routinely in labor to all patients in whom dental prophylaxis is indicated.

Low prevalence of (pre) malignant lesions in the breast and high prevalence in the ovary and Fallopian tube in women at hereditary high risk of breast and ovarian cancer

To analyse the prevalence of (pre) malignant lesions occurring in breast and adnexal tissue at prophylactic surgery in women at hereditary high risk of breast and/or ovarian cancers. Tissue was obtained from 85 women who underwent prophylactic bilateral salpingo-oophorectomy (pBSO) and from 59 women who underwent prophylactic mastectomy (pM). Control tissue samples were obtained from women undergoing breast reduction surgery (N = 99) or adnexal surgery for benign reasons (N = 72). In women with a BRCA1/2 mutation, the prevalence of a (pre) malignant adnexal lesion was 50% (95% CI 26-74) if older than 40 years and 14% (95% CI 0-58) if younger. The prevalences of (pre) malignant breast lesions in women older than 40 years, with and without a BRCA1/2 mutation, were 0% (95% CI 0-16) and 47% (95% CI 21-73), respectively. No association was found between (pre) malignant lesions in breast and adnexal tissue occurring in 28 women who underwent surgery on both organs (R = 0.155, p = 0.432), but the prevalence of lesions was significantly higher in adnexal tissue than in the breast (p = 0.023). Compared to controls, women at hereditary high risk had a higher chance of (pre) malignant lesions in the breast and an even higher chance of such lesions in the adnexal tissue. There was no indication for concomitant presence of such lesions in both organs at the time of prophylactic surgery. The high frequency of (pre) malignant lesions in the adnexal tissue stresses further the importance of pBSO from the age of 40 onwards in women at hereditary high risk.