Allelotype of papillary serous peritoneal carcinomas

Genomic Catastrophe (Chromothripsis and Polyploidy) Correlates With Tumor Distribution in Extrauterine High-grade Serous Carcinoma

Most extrauterine high-grade serous carcinomas (HGSCs) are thought to develop first in the distal fallopian tube. Most models of HGSC assume origin from relatively stable, noninvasive serous tubal intraepithelial carcinomas. However, widespread tumor involvement in the absence of a serous tubal intraepithelial carcinoma could occur after catastrophic genomic events (CGEs; such as chromothripsis or polyploidy). Twenty-six HGSCs assigned to fallopian tube (n = 9, group 1) and/or ovary (n = 9, group 2), and primary peritoneal (n = 8, group 3) were assessed by microarray (Oncoscan). CGEs were identified in 15/26 (57.7%); chromothripsis-like pattern in 13/26 (50.0%) and polyploidy in 6/26 (23.1%). CGE was seen in 4/9 (44.4%), 9/9 (100%), and 2/8 (25%) cases in groups 1. 2, and 3, respectively. Overall, CGEs were seen in 9/9 (100%) cases with grossly evident ovarian parenchymal involvement versus 6/17 (35.3%) without (P = 0.0024). Ovarian size (measured on the long axis) correlated with CGE positivity (P = 0.016). CGEs are significantly more common in HGSCs with ovarian parenchymal involvement compared with those limited to the fallopian tube and/or extraovarian tissues. These associations suggest geographically different tumor growth patterns and support the subdivision of HGSCs according to not only the stage but also tumor distribution. They have implications for clinical and pathologic presentation, trajectory of tumor evolution, and in the case of primary peritoneal HGSCs, potentially unique precursors to tumor transitions that could inform or influence cancer prevention efforts.

Development and Validation of Prognostic Nomogram for Primary Peritoneal Serous Carcinoma Compared With FIGO Staging System: A Population-Based Study

Background

Primary peritoneal serous carcinoma (PPSC) is a rare tumor that lacks a prognostic prediction model. Our study aims to develop a nomogram to predict overall survival (OS) of PPSC patients.

Methods

Patients confirmed to have PPSC between 2004 and 2012 were selected from the Surveillance, Epidemiology, and End Results (SEER) database. LASSO and multivariate Cox regression analyses were used to screen for meaningful independent prognostic factors to construct a nomogram model for 3-, 5-, and 10-year OS among patients with PPSC. The nomogram compared the discrimination, calibration, and net benefits with the International Federation of Gynecology and Obstetrics (FIGO) staging system of PPSC patients.

Results

Eight variables were selected to establish the nomogram for PPSC. The established nomogram performed significantly better than the FIGO staging system (p < 0.05). The 3-, 5-, and 10-year OS of PPSC was 0.498, 0.306, and 0.152, respectively. Patients of old age, widowed marital status, grade high, FIGO IIIB, IIIC, or IV, lymph node metastasis, no lymphadenectomy, no surgery, and no chemotherapy got higher score which corresponds with higher risk and lower OS. In the multivariate Cox regression analysis, age, histological grade, FIGO staging, lymph node metastasis, and lymphadenectomy (four or more) were identified as independent prognostic factors for PPSC.

Conclusions

PPSC patients have distinct characteristics with respect to their presentation and survival outcomes. A prognostic nomogram constructed by various clinical indicators can provide better and more accurate predictions for patients with PPSC.

Narrative review on serous primary peritoneal carcinoma of unknown primary site: four questions to be answered

Serous peritoneal papillary carcinoma (SPPC) represents a particular cancer of unknown primary (CUP) entity that arises in the peritoneal surface lining the abdomen and pelvis without a discriminative primary tumor site. In this review, we discuss the validity of SPPC as a distinct entity. Clinically, patients with SPPC are older, have higher parity and later menarche, are more often obese and probably have poorer survival compared to those with primary ovarian cancer. Pathologically, SPPC is more anaplastic and multifocal, unlike primary ovarian cancer which is commonly unifocal. Biologically, it presents a higher expression of proliferative signals and similar cell cycle and DNA repair protein expression. These differences hint towards SPPC and primary ovarian cancer being as a spectrum of disease. Patients with SPPC are traditionally managed similarly to stage III–IV ovarian cancer. The recommended approach integrates aggressive cytoreductive surgery, hyperthermic intraperitoneal chemotherapy, and systemic chemotherapy to remove the macroscopic tumor, eradicate the microscopic residual disease, and control the microscopic metastasis. However, the available evidence lacks proper randomized or prospective studies on SPPC and is limited to retrospective series. The diligent identification of SPPC is warranted to design specific clinical trials that eventually evaluate the impact of the new therapeutics on this distinct entity.

Genetic landscape of a case of extraovarian peritoneal serous papillary carcinoma

The present report aimed to study genetic alterations underlying extraovarian peritoneal serous papillary carcinoma (EPSPC), which have not previously been systematically investigated. A case of EPSPC was identified, and its genetic alterations were assessed by combining comparative genomic hybridization and whole-exome sequencing technologies to investigate the genomic landscape, including copy number variations and mutations in EPSPC. It was found that a large number of germline mutations were present, which may have predisposed the patient to the occurrence of this disease. Copy number gains were found in a range of chromosomes, including 4q, 5q, 8q, 10q, 15q, 16p, 18q, 20p, 20q and Xq. Large-scale copy number loss occurred in chromosomes 2p, 13q, 16q, 17p and 17q. Through use of whole-exome sequencing, germline mutations were widely found that were associated with cancer development, including mutations in the BRCA1, DNA repair associated (BRCA1), BRCA2, tumor protein 53, erb-b2 receptor tyrosine kinase 2, matrix metalloproteinases and ADAM metallopeptidase domain-containing genes. In addition, 165 somatic mutations, including 52 missense mutations and 7 short insertions or deletions, were also identified. In summary, the EPSPC was undergoing profound genomic rearrangement and somatic mutation, which may have led to its initiation and development, and the present study discussed the genetic basis of this highly malignant cancer.

Serous ovarian, fallopian tube and primary peritoneal cancers: a common disease or separate entities - a systematic review

OBJECTIVE

The aim of this systematic review is to analyze data on risk factors, epidemiology, clinicopathology and molecular biology from studies comparing primary peritoneal cancer, fallopian tube cancer and ovarian cancer of serous histology, in order to achieve a greater understanding of whether or not these disorders should be considered as separate entities.

METHODS

A systematic literature search was conducted in PubMed and MEDLINE. Case-control studies comparing primary serous peritoneal or fallopian tube carcinomas with primary serous ovarian carcinomas or a control group were included.

RESULTS

Twenty-eight studies were found eligible. Primary peritoneal cancer patients were older, had higher parity, were more often obese and had poorer survival compared to ovarian cancer patients. Differences in protein expression patterns of Her2/neu, estrogen and progestin receptors and frequency of loss of heterozygosity differed between primary peritoneal cancer and primary ovarian cancer patients. No major differences were found between primary fallopian tube cancer and primary ovarian cancer. The proportion of serous tubal intraepithelial carcinomas (STIC) was lower in primary peritoneal cancer and primary ovarian cancer compared to primary fallopian tube cancer.

CONCLUSION

Except from differences in the proportion of STIC only few differences between primary fallopian tube cancer and primary ovarian cancer have been found. In contrast, observed differences in risk factor profile, clinicopathologic and prognostic factors, as well as in the molecular patterns, indicate that peritoneal cancer and ovarian cancer may be linked to different carcinogenic pathways.

Serous papillary peritoneal carcinoma: unknown primary tumour, ovarian cancer counterpart or a distinct entity? A systematic review

INTRODUCTION

Serous peritoneal papillary carcinoma (SPPC), though managed according to ovarian cancer therapeutic principles, has been variably considered as an ovarian cancer counterpart, a peritoneal malignancy with distinct characteristics or a cancer of unknown primary (CUP).

PATIENTS AND METHODS

We systematically reviewed all publications studying molecular pathophysiology, clinical presentation, management and outcome of at least 10 patients with SPPC from 1980 to 2008 in anglophone medical journals and critically analysed the data.

RESULTS

Molecular profiling of CUP was performed in eight papers reporting on 211 patients with stage III/IV SPPC by means of immunohistochemistry or PCR-based assays. Twenty-five clinical series, mostly retrospective, reported management and outcome of 579 patients with SPPC, in several cases matched to advanced ovarian cancer controls. Though we did not identify statistically significant differences in molecular biology, clinical presentation, management and outcome of SPPC and ovarian cancer cases, some subtle differences emerged: patterns of loss of heterozygosity at several chromosomal loci differed from those seen in ovarian cancer, while the overexpression of the HER2 oncogene was encountered more often. Serous peritoneal tumours affected older patients and were more frequently multifocal or exhibited virulent clonal expansion in metastatic sites. Diffuse micronodular spread formed a high total load of malignancy in omental, peritoneal surfaces, difficult to debulk optimally. Despite effective chemotherapeutic cytoreduction and occasional long-term remissions, SPPC patients survived 2-6 months less than ovarian cancer patients.

CONCLUSIONS

Patients with SPPC should not be classified in the poor-risk CUP category, in view of the therapeutic and prognostic differences. Still, the assimilation of the SPPC entity by ovarian cancer hindered further research into its genotypic and phenotypic characteristics that may differ from ovarian cancer. Subgroup analyses of large ovarian cancer trials may shed light in this issue.

Potentially important microRNA cluster on chromosome 17p13.1 in primary peritoneal carcinoma

MicroRNAs are a group of small non-coding RNAs approximately 22 nucleotides in length. Recent work has shown differential expression of mature microRNAs in human cancers. We characterized the alteration in expression of a select group of microRNAs in primary peritoneal carcinoma relative to matched cases of ovarian serous carcinoma. MicroRNA expression was analysed using semi-quantitative stem-loop RT-PCR on a set of 34 formalin-fixed paraffin-embedded samples. Protein expression of p53 and bcl-2 was quantified in the corresponding tissue microarray. We provide definitive evidence that there is downregulation of a select group of microRNAs in tumours meeting Gynaecological Oncology Group criteria for primary peritoneal carcinoma relative to ovarian serous carcinoma. Specifically, we show decreased p53 expression and downregulation of miR-195 and miR-497 from the microRNA cluster site at chromosome 17p13.1 in primary peritoneal carcinoma relative to ovarian serous carcinoma. miR-195 and miR-497 may have potential roles as tumour-suppressor genes in primary peritoneal tumourigenesis.

Effects of raf kinase inhibitor protein expression on metastasis and progression of human epithelial ovarian cancer

Loss of function of metastasis suppressor genes is an important step in the progression to a malignant tumor type. Studies in cell culture and animal models have suggested a role of Raf kinase inhibitor protein (RKIP) in suppressing the metastatic spread of prostate cancer, breast cancer, and melanoma cells. However, the function of RKIP in ovarian cancer (OVCA) has not been reported. To explore the potential role of RKIP in epithelial OVCA metastasis, we detected the expression levels of RKIP protein in tissue samples from patients with epithelial OVCA. Consequently, the expression of RKIP is reduced in the poorly differentiated OVCA than in the well-differentiated and moderately differentiated OVCA. In addition, in vitro cell invasion assay indicated that the RKIP expression was inversely associated with the invasiveness of five OVCA cell lines. Consistent with this result, the cell proliferation, anchorage-independent growth, cell adhesion, and invasion were decreased in RKIP overexpressed cells but increased in RKIP down-regulated cells. Further investigation indicated that RKIP inhibited OVCA cell proliferation by altering cell cycle progression rather than promoting apoptosis. Furthermore, the overexpression of RKIP suppressed the ability of human OVCA cells to metastasize when the tumor cells were transplanted into nude mice. Our data show the effect of RKIP on the proliferation, migration, or adhesion of OVCA cells. These results indicate that RKIP is also a metastasis suppressor gene of human epithelial OVCA.

Body size and risk of epithelial ovarian and related cancers: a population-based case-control study

Different subtypes of ovarian cancer appear to have different causes; however, the association between body mass index (BMI) and the different subtypes is unclear. We examined the associations between body-mass index (BMI) and weight gain and risk of the different histological subtypes of epithelial ovarian cancer in a case-control study in Australia. Cases aged 18-79 with a new diagnosis of invasive epithelial ovarian cancer (n = 1,269) or borderline tumor (n = 311) were identified through a network of clinics and cancer registries throughout Australia. Controls (n = 1,509) were selected from the Electoral Roll. Height and weight (1 year previously, at age 20 and maximum weight) and other risk factor information were ascertained via a self-administered questionnaire. Obesity was positively associated with clear cell tumors (Odds Ratio 2.3; 95% confidence interval 1.2-4.2) but not invasive endometrioid or mucinous tumors. Although there was no association with invasive serous tumors overall (0.9; 0.7-1.2), we did see an increased risk of serous peritoneal tumors (2.9; 1.7-4.9), but not of serous tumors of the ovary and fallopian tube. Of the borderline subtypes, obesity was positively associated with serous (1.8; 1.1-2.8) but not mucinous tumors (1.1; 0.7-1.7). Overweight was not associated with any subtype overall. There was no association with BMI at age 20, or weight gain for any of the histological subtypes. These results add to the current evidence that obesity increases a woman's risk of developing distinct histological subtypes of 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.

HOXA10 expression in endometrial adenocarcinoma

Homeobox (HOX) genes are highly evolutionarily conserved regulators of embryonic differentiation. HOX genes are also expressed in normal adult reproductive tissue where they are involved in regulating differentiation. We hypothesized that HOXA10 gene expression may be altered in endometrial adenocarcinoma. To assess HOXA10 gene expression, endometrial tissue was obtained from 32 subjects with normal endometrium or disease confined to the uterus. Nine specimens contained normal endometrium, 5 had endometrial hyperplasia and 18 had stage I and II endometrial adenocarcinoma. RNA was extracted, Northern blot analysis performed and expression of HOXA10 assessed by densitometry. Expression of estrogen receptor, progesterone receptor and p53 was analyzed by immunohistochemistry. HOXA10 was expressed in both normal and neoplastic endometrium. No significant difference in HOXA10 expression was found between normal, hyperplastic and FIGO nuclear grade 1 endometrial tissues. Expression of HOXA10 was increased by 25% in high nuclear grade endometrial adenocarcinomas compared with normal, hyperplastic and low nuclear grade endometrial adenocarcinomas. No difference was noted in expression of estrogen receptor, progesterone receptor or p53. HOXA10 expression is elevated in high nuclear grade stage I and II endometrial adenocarcinomas. Aberrant regulation of HOX gene expression is associated with abnormal differentiation of endometrial tissue.

Allelic imbalance regions on chromosomes 8p, 17p and 19p related to metastasis of hepatocellular carcinoma: comparison between matched primary and metastatic lesions in 22 patients by genome-wide microsatellite analysis

To understand the molecular mechanisms of metastasis in hepatocellular carcinoma (HCC), it is necessary to identify the accumulating genetic alterations during its progression as well as those responsible for the acquisition of metastatic potential in cancer cells. In our previous study, using comparative genomic hybridization (CGH), we found that loss on chromosome 8p is more frequent in metastatic lesions than in matched primary tumors of HCC. Thus, 8p deletion might contribute to HCC metastasis. To narrow the location of metastasis-related alteration regions, we analyzed 22 primary and matched metastatic lesions of HCC by genome-wide microsatellite analysis. Common regions with high levels of allelic imbalance (AI) were identified on 17p, 8p11-cen, 8p21-23, 4q32-qter, 4q13-23, 16q, and 1p33. Regions with increased AI in metastatic lesions were 8p23.3, 8p11.2, 17p11.2-13.3, 4q21-22, 4q32-qter, 8q24.1, 9p11, 9q31, 11q23.1, 13q14.1-31, 13q32-qter, 16p13.3, 16q13, 16q22, and 19p13.1, and these were considered to be related to the metastasis phenotype. Among them, loss on 8p was again proved to be related to progression and metastasis of HCC, and 8p23.3 and 8p11.2 were two likely regions harboring metastasis-related genes. It was also shown for the first time in HCC that AI of 19p13.1 might also be related to metastatic potential. These results provide some candidate regions for further study to identify putative genes suppressing metastasis of HCC.