Abstract Circulating tumor DNA (ctDNA) provides great potential for the non-invasive clinical assessment of tumor burden. We developed a monitoring protocol using next generation mate-pair sequencing to identify chromosomal rearrangement signatures in primary tumors to follow ctDNA in blood. Primary tumors of 10 patients with ovarian cancer were sequenced, and individualized tumor-specific panels were designed to detect the junctions in ctDNA. A novel algorithm was developed and applied to data generated by quantitative PCR to calculate the percent of ctDNA. Selected junctions, some with potential as therapeutic targets, were detected in pre-surgically drawn blood in eight out of ten patients. Of these eight, three demonstrated the continued presence of circulating tumor DNA post-surgery, and five had undetectable levels, consistent with their documented presence or absence of disease. The detection of somatic junctions derived from ctDNA could be an effective way to monitor ovarian cancer patients for relapse and therapy response. Citation Format: Faye R. Harris, Irina Kovtun, James Smadbeck, Francesco Multinu, Aminah Jatoi, Kimberly R. Kalli, Stephen J. Murphy, Geoffrey C. Halling, Farhad Kosari, Sarah H. Johnson, Andrea Mariani, George Vasmatzis. Quantification of somatic chromosomal rearrangements in circulating cell-free DNA from ovarian cancers. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 440.
The role of surgery in recurrent endometrial cancer
Abstract High-grade serous (HGS) ovarian cancer is the most lethal form of epithelial ovarian cancer because it represents the most common histologic subtype and usually present at an advanced stage. Due to its advanced stage presentation, HGS ovarian cancer has been described as arising de novo from undefined precursor lesions that progress rapidly to advanced disease. To gain insights into clonal heterogeneity and progression to distant metastases, we analyzed single nucleotide variations (SNVs) from nine regions of carcinomas from four patients with HGS ovarian cancer. Three primary sites, three metastases from omentum, and three metastases from bowel were collected from each patient and subjected to RNA sequencing and SNV analysis. Although a modest number (23.62%) of SNVs are shared within the same anatomic site, only limited number (1.26%) of SNVs are shared among all 9 sites, suggesting a high degree of intratumor heterogeneity in these patients. Truncal mutations, such as TP53 mutations, are shared among all sites and observed at high allele frequencies. In addition, mutations in genes associated with epigenetic modifiers, such as SETD2, CHD8, KDM5A, SMARCA1 and ARID5B are observed as truncal mutations in these patients. Phylogenetic tree reconstruction of tumors from various sites suggests a concurrent ovarian and peritoneal metastases in one patient and peritoneal metastases preceding the ovarian carcinomas in three other patients. Finally, subclone inference from multi-region sequencing indicates the presence of multiple subclones at each site in these patients. Dominant subclones, present at metastases, are often ancestral clones in the clonal hierarchy, further providing evidence that peritoneal spreading occurs early in the clonal expansion. Collectively, these results provide evidence for early peritoneal spreading that often precedes ovarian carcinomas in HGS ovarian cancer. This abstract is also presented as Poster B44. Citation Format: Jeremy Chien, Viji Shridhar, Andrea Mariani. Evidence for extra-ovarian origin and peritoneal metastases that precede ovarian carcinomas in high-grade serous ovarian cancer. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research: Exploiting Vulnerabilities; Oct 17-20, 2015; Orlando, FL. Philadelphia (PA): AACR; Clin Cancer Res 2016;22(2 Suppl):Abstract nr PR08.
Abstract B80: Tumor expression subtypes of high-grade serous ovarian cancer demonstrate associations with likelihood of complete resection: a single-center study.
Abstract Purpose: Ovarian cancer (OC) patients received maximum benefits when complete dissection with no macroscopic disease is achieved. It has been suggested that surgical outcome is associated with tumor biology and therefore can be predicted from tumor molecular characteristics such as gene expression levels. Noticeably, several debulking-associated genes have been independently reported based on meta-data analysis and further validations in individual center's cohorts. Furthermore, a recent OC study of the cancer genome atlas (TCGA) project revealed the presence of four expression subtypes in high-grade serous ovarian cancer (HGSOC). We have independently confirmed this association with prognosis in our OC cohort. With the awareness that surgical practices and rates of complete resection vary among institutions, we sought to evaluate whether expression changes of previously reported debulking-associated genes are associated with complete dissection in a HGSOC cohort in a center with an aggressive surgical approach. Further, we also tested if the HGSOC four expression subtypes are associated with complete dissection. Experimental Design: We constructed a cohort of 262 stage III/IV HGSOC patient cases diagnosed in Mayo Clinic between 1993 and 2011. Cases were categorized into two groups based upon debulking outcome: 84 complete resection cases with no gross visible residual disease (RD0), 178 cases with residual disease greater than 0 cm (RD1). Tumor mRNA expression was previously measured using Agilent 4x44k platforms. Eight previously published debulking-associated genes were evaluated for their expression differences between RD0 and RD1 patient groups using t-test: FABP4, ADH1B, POSTN, CXCL14, FAP, NUAK1, PTCH1 and TGFBR2. For testing subtype-debulking associations, we first quantified molecular subtype activation scores of individual tumors using single-sample gene set enrichment analysis (ssGSEA), and computed standardized scores after permutation-based scaling adjustments to account for gene set size difference. Then, standardized subtype scores are associated with complete dissection (RD0) vs. other surgical outcome (RD1) using logistic regression. The independent subtype-associations were further evaluated by adjusting known debulking outcome factors, including age, ascites, tumor grade and stage. Results: For eight previously reported debulking-associated genes, only one demonstrated a significant expression difference between RD0 and RD1 groups: CXCL14, t-test p-value = 9.2x10-3. When comparing debulking vs. HGSOC subtypes, we observed a significantly reduced probability of complete resection for the mesenchymal subtype (p-value = 1.1x10-2, OR = 0.56, 95% CI [0.35, 0.87]). Consistent with this observation, we have previously described the mesenchymal subtype as a poor prognosis group. On the other hand, the immunoreactive subtype was associated with a higher likelihood of complete resection (p-value = 9.4 x 10-3, OR=2.19, 95% CI = [1.22, 4.01]). The significant associations between these two subtype activities and complete resection in advanced stage disease remained after adjusting for age, ascites, tumor grade and sub-stage: mesenchymal (p-value = 1.5 x 10-2 ,OR = 0.48, 95% CI = [0.26, 0.85]); immunoreactive subtype (p-value = 4.8 x 10-2 , OR = 2.11, 95% CI = [1.04, 4.53]). Conclusion: This single center HGSOC analysis demonstrates the important of validation of debulking signatures in centers with diverse rates of complete resection. We were only able to validate an association with complete resection for one of eight previously reported debulking-associated genes. We also showed that HGSOC subtypes have significant associations with likelihood of complete dissection. Further studies are warranted for confirming subtype associations in other institutional HGSOC cohorts. Citation Format: Chen Wang, Jamie Bakkum-Gamez, Andrea Mariani, William Cliby, Ellen Goode. Tumor expression subtypes of high-grade serous ovarian cancer demonstrate associations with likelihood of complete resection: a single-center study. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research: Exploiting Vulnerabilities; Oct 17-20, 2015; Orlando, FL. Philadelphia (PA): AACR; Clin Cancer Res 2016;22(2 Suppl):Abstract nr B80.
Preoperative selection of endometrial cancer patients at low risk for lymph node metastases: useful criteria for enrollment in clinical trials
AbstractThe aim of the present review is to summarize the current evidence on the role of pelvic and para‐aortic lymphadenectomy in endometrial cancer. In 1988, the International Federation of Obstetrics and Gynecology recommended surgical staging for endometrial cancer patients. However, 25 years later, the role of lymph node dissection remains controversial. Although the findings of two large independent randomized trials suggested that pelvic lymphadenectomy provides only adjunctive morbidity with no clear influence on survival outcomes, the studies have many pitfalls that limit interpretation of the results. Theoretically, lymphadenectomy may help identify patients with metastatic dissemination, who may benefit from adjuvant therapy, thus reducing radiation‐related morbidity. Also, lymphadenectomy may eradicate metastatic disease. Because lymphatic spread is relatively uncommon, our main effort should be directed at identifying patients who may potentially benefit from lymph node dissection, thus reducing the rate of unnecessary treatment and associated morbidity. This review will discuss the role of lymphadenectomy in endometrial cancer, focusing on patient selection, extension of the surgical procedure, postoperative outcomes, quality of life and costs. The need for new surgical studies and efficacious systemic drugs is recommended.
Sugar-Sweetened Beverage Intake and the Risk of Type I and Type II Endometrial Cancer among Postmenopausal Women
HE4, also known as WFDC2, is a useful biomarker for ovarian cancer when either used alone or in combination with CA125. HE4 is also overexpressed in endometrial cancer (EC), but its function in cancer cells is not clear. In this study, we investigate the role of HE4 in EC progression. An HE4-overexpression system was established by cloning the HE4 prototypic mRNA variant (HE4-V0) into a eukaryotic expression vector. Following transfection, stable clones in two EC cell lines were selected. The effects of HE4 overexpression on cell growth and function were measured with the use of cell proliferation assay, matrigel invasion, and soft agar gel colony formation assays. HE4-induced cancer cell proliferation in vivo was examined in a mouse xenograft model. HE4 overexpression significantly enhanced EC cell proliferation, matrigel invasion, and colony formation in soft agar. Moreover, HE4 overexpression promoted tumor growth in the mouse xenograft model. HE4 overexpression enhanced several malignant phenotypes in cell culture and in a mouse model. These results are consistent with our previous observation that high levels of serum HE4 closely correlate with the stage, myometrial invasion and tumor size in patients with EC. This study provides evidence that HE4 overexpression directly impacts tumor progression in endometrial cancer.
Conservative Management of Atypical Hyperplasia and Grade I Endometrial Carcinoma: Review of the Literature and Presentation of a Series