Recurrent patterns of DNA methylation in the ZNF154, CASP8, and VHL promoters across a wide spectrum of human solid epithelial tumors and cancer cell lines

The study of aberrant DNA methylation in cancer holds the key to the discovery of novel biological markers for diagnostics and can help to delineate important mechanisms of disease. We have identified 12 loci that are differentially methylated in serous ovarian cancers and endometrioid ovarian and endometrial cancers with respect to normal control samples. The strongest signal showed hypermethylation in tumors at a CpG island within the ZNF154 promoter. We show that hypermethylation of this locus is recurrent across solid human epithelial tumor samples for 15 of 16 distinct cancer types from TCGA. Furthermore, ZNF154 hypermethylation is strikingly present across a diverse panel of ENCODE cell lines, but only in those derived from tumor cells. By extending our analysis from the Illumina 27K Infinium platform to the 450K platform, to sequencing of PCR amplicons from bisulfite treated DNA, we demonstrate that hypermethylation extends across the breadth of the ZNF154 CpG island. We have also identified recurrent hypomethylation in two genomic regions associated with CASP8 and VHL. These three genes exhibit significant negative correlation between methylation and gene expression across many cancer types, as well as patterns of DNaseI hypersensitivity and histone marks that reflect different chromatin accessibility in cancer vs. normal cell lines. Our findings emphasize hypermethylation of ZNF154 as a biological marker of relevance for tumor identification. Epigenetic modifications affecting the promoters of ZNF154, CASP8, and VHL are shared across a vast array of tumor types and may therefore be important for understanding the genomic landscape of cancer.

A prospective study evaluating the clinical relevance of a chemoresponse assay for treatment of patients with persistent or recurrent ovarian cancer

OBJECTIVE

Use of in vitro chemoresponse assays for informing effective treatment selection is a compelling clinical question and a topic of debate among oncologists. A prospective study was conducted evaluating the use of a chemoresponse assay in recurrent ovarian cancer patients.

METHODS

Women with persistent or recurrent ovarian cancer were enrolled under an IRB-approved protocol, and fresh tissue samples were collected for chemoresponse testing. Patients were treated with one of 15 protocol-designated treatments empirically selected by the oncologist, blinded to the assay results. Each treatment was classified by the assay as: sensitive (S), intermediate (I), or resistant (R). Patients were prospectively monitored for progression-free survival (PFS) and overall survival (OS). Associations of assay response for the physician-selected treatment with PFS and OS were analyzed.

RESULTS

A total of 262 evaluable patients were enrolled. Patients treated with an assay-sensitive regimen demonstrated significantly improved PFS and OS while there was no difference in clinical outcomes between I and R groups. Median PFS was 8.8 months for S vs. 5.9 months for I+R (hazard ratio [HR]=0.67, p=0.009). The association with assay response was consistent in both platinum-sensitive and platinum-resistant tumors (HR: 0.71 vs. 0.66) and was independent of other covariates in multivariate analysis (HR=0.66, p=0.020). A statistically significant14-month improvement in mean OS (37.5 months for S vs. 23.9 months for I+R, HR=0.61, p=0.010) was demonstrated.

CONCLUSIONS

This prospective study demonstrated improved PFS and OS for patients with either platinum-sensitive or platinum-resistant recurrent ovarian cancer treated with assay-sensitive agents.

Assessment of the Prognostic Value of Two Common Variants of BRCA1 and BRCA2 Genes in Ovarian Cancer Patients Treated with Cisplatin and Paclitaxel: A Gynecologic Oncology Group Study

Purpose: BRCA1/BRCA2 germline mutations appear to enhance the platinum-sensitivity, but little is known about the prognostic relevance of polymorphisms in BRCA1/BRCA2 in epithelial ovarian cancer (EOC). This study evaluated whether common variants of BRCA1/BRCA2 are associated with progression-free survival (PFS) and overall survival (OS) in patients with advanced stage sporadic EOC.

Experimental Design: The allelic frequency of BRCA1 (2612C > T, P871L-rs799917) and BRCA2 (114A > C, N372H-rs144848) were determined in normal blood DNA from women in Gynecologic Oncology Group protocol #172 phase III trial with optimally resected stage III EOC treated with intraperitoneal or intravenous cisplatin and paclitaxel (C + P). Associations between polymorphisms and PFS or OS were assessed.

Results: Two hundred and thirty-two women were included for analyses. African Americans (AA) had different distributions for the two polymorphisms from Caucasians and others. For non-AA patients, the genotype for BRCA1 P871L was distributed as 38% for CC, 49% for CT, and 13% for TT. Median PFS was estimated to be 31, 21, and 21 months, respectively. After adjusting for cell type, residual disease, and chemotherapy regimen, CT/TT genotypes were associated with a 1.40-fold increased risk of disease progression [95% confidence interval (CI) = 1.00–1.95, p = 0.049]. After removing seven patients with known BRCA1 germline mutations, the hazard ratio (HR) was 1.36 (95% CI = 0.97–1.91, p = 0.073). The association between BRCA1 P871L and OS was not significant (HR = 1.25, 95% CI = 0.88–1.76, p = 0.212). Genotype distribution of BRCA2 N372H among non-AA patients was 50, 44, and 6% for AA, AC, and CC, respectively and there is no evidence that this BRCA2 polymorphism was related to PFS or OS.

Conclusion: Polymorphisms in BRCA1 P871L or in BRCA2 N372H were not associated with either PFS or OS in women with optimally resected, stage III EOC treated with cisplatin and paclitaxel.

Upper abdominal procedures in advanced stage ovarian or primary peritoneal carcinoma patients with minimal or no gross residual disease: an analysis of Gynecologic Oncology Group (GOG) 182

PURPOSE

To examine the utility of upper abdominal procedures (UAPs) performed in a cohort of optimally cytoreduced patients with advanced stage epithelial ovarian cancer (EOC) or primary peritoneal cancer (PPC) and identify potential areas where aggressive surgery may impact survival.

PATIENTS AND METHODS

We reviewed 2655 patients enrolled in Gynecologic Oncology Group (GOG) 182 who had complete resection (CR) or minimal residual (MR) disease <1cm. Demographic, pathologic, surgical, and outcome data were collected. UAPs included diaphragm stripping or resection, liver resection, splenectomy, pancreatectomy, and porta hepatis surgery. Effect of UAP and CR on PFS/OS was assessed by Kaplan-Meier and proportional hazards methods.

RESULTS

Four-hundred eighty-two patients (18.1%) underwent a total of 590 UAPs. There were 351 (13.1%) diaphragm surgeries, 112 (4.2%) liver surgeries, 108 (4%) splenectomies, 12 (0.5%) pancreatectomies, and 7 (0.2%) porta hepatis surgeries. Comparing patients who did not have UAPs to patients who had UAPs, the PFS was 18.2 months (mos) and 14.8 mos (p < 0.01) and OS was 49.8 mos v. 43.7 mos (p = 0.01), respectively. However, in the multivariable analysis this survival benefit did not remain (PFS HR = 1.03, 95% CI 0.91-1.15; OS HR=0.92, 95%CI 0.81-1.04). The OS of the 141 patients who had an UAP and achieved CR compared to the 341 patients who had an UAP with MR was 54.6 compared to 40.4 mos (p=0.0005).

CONCLUSIONS

UAP procedures should only be performed when CR is attainable. A significant proportion of patients with MR were left with diaphragmatic disease that could potentially be completely resected.

Multimodal therapy in patients with node-positive (stage IIIC) uterine papillary serous carcinoma: A National Cancer Database study

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Background: Uterine papillary serous carcinoma (UPSC) is an aggressive endometrial cancer that carries a 30-40% risk of nodal metastasis. Adjuvant systemic chemotherapy has become standard of care in advanced UPSC, but the role of additional adjuvant radiotherapy is unclear. This study aims to evaluate survival outcomes of multimodal therapy through the use of the National Cancer Data Base (NCDB). Methods: All patients diagnosed with surgically-staged FIGO stage IIIC uterine papillary serous carcinoma were identified in the NCDB from 1/1998 through 12/2010. Patients were divided into those who received chemotherapy only (CT) and both chemotherapy and radiation therapy (CT+RT). Overall survival was estimated using the Kaplan-Meier method. Univariate comparison by log rank test and multivariable analysis by Cox regression modeling were performed to identify and control for prognostic factors. Results: A total of 13,356 cases of uterine cancer were identified, of which 794 were UPSC. Of these patients, 387 underwent lymphadenectomy (median 14 nodes removed) with 75 patients (median age 65) found to have stage IIIC disease. Median follow up is 20.4 (range: 0-114) months. There were no significant differences were found between the RT and CT+RT group with regards to patient demographic, medical comorbidity, treatment facility or disease characteristics. The median overall survival was 23.2 (95% CI 14.5-31.9) and 40.3 (95% CI 31.5-49.1) months, (p<0.05) for the CT and CT+RT groups, respectively. Multivariate analysis controlling for age, race, income, Charlson-Deyo comorbidity index, treatment facility type, year of diagnosis, number of lymph nodes removed, number of positive lymph nodes and tumor size found radiotherapy independently predicted improved survival [HRdeath0.024 (95% CI 0.001-0.668)]. Conclusions: Patients with stage IIIC UPSC benefit from adjuvant radiotherapy in addition to adjuvant chemotherapy.

A proteomic analysis of surgical cytoreduction in patients with advanced ovarian cancer

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Background: Optimal surgical cytoreduction (<1 cm residual tumor) has been shown to improve overall survival compared to suboptimal (>1cm) debulking as primary treatment for advanced stage epithelial ovarian cancer (EOC). Molecular descriptions of optimally and suboptimally debulked ovarian tumors are lacking. We have performed a global, quantitative proteomic analysis of optimally and suboptimally debulked EOC tumor samples. Methods: A cohort of 16 optimally (8) and suboptimally (8) debulked patients with archival formalin-fixed, paraffin-embedded tumor specimens was identified. Homogenous tumor cell populations were collected and protein digests were prepared and analyzed by high resolution mass spectrometry for identification and quantification by spectral counting. Immunohistochemistry (IHC) was performed and slides were scored using a semi-quantitative method (H-score). Results: An average of 1,110 proteins were identified within each cohort, of which 21 possessed significant (p<0.05) differential abundances. Specifically, three proteins (annexin A1, S100-A11, and synuclein-gamma, or SNCG) which have significant roles in cell migration and cancer biology were identified. Although no H-score was statistically significant, comparison of positively-staining cells for SNCG showed a trend toward increased expression in suboptimally debulked patients, p=0.08. Conclusions: Overexpression of SNCG has been shown to be predictive of worse prognosis in papillary serous uterine cancer cell lines, and increased expression of SNCG in breast cancer correlates with advanced stage and aggressiveness of disease. Our data suggest SNCG may have similar predictive value in EOC, as tumors with elevated levels of this protein may be less amenable to optimal cytoreduction.

In vitro chemoresponse assay results and population clinical response rates in women with ovarian cancer

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Background: While platinum-based chemotherapies have been identified as the most effective agents in ovarian cancer, they are not effective in all women. An in vitro assay that determines whether platinum agents are likely to be effective for individual patients could have clinical utility. This study determines whether in vitro platinum sensitivity rates are similar to published population response rates for ovarian cancer and examines differences in platinum sensitivity across histologic subtypes. Methods: In vitro chemoresponse testing (ChemoFx, Precision Therapeutics, Pittsburgh, PA) was performed on tumors from 3,130 patients with primary or recurrent epithelial ovarian cancers. Histologic subtypes included serous, endometrioid, clear cell, and mucinous. Primary cancers, stages II-IV, were examined. Tumors were classified as responsive (R), intermediately responsive (IR), or non-responsive (NR) to chemotherapy. The rates of pan-resistance (Pan R), defined as non-responsive to all agents tested, was also examined in both primary and recurrent tumors. Statistical analyses were conducted using the Chi-square test with Bonferroni correction where appropriate. Results: Of 3,130 eligible patients, 2,335 had stage II-IV primary tumors (75%); the remaining 795 (25%) were recurrent. Overall, 77% of primary tumors were responsive (R or IR) to combination carboplatin/paclitaxel (CP). CP response rate was significantly different across histologic subtypes (p<0.001), with serous tumors exhibiting the highest response rate (79%). CP response was significantly greater in serous tumors (79%) when compared to mucinous tumors (65%; p=0.03). CP response was significantly greater in primary tumors (77%) when compared to recurrent tumors (65%)(p<0.001). In addition, the rate of pan R was significantly greater in recurrent tumors (26%) compared to primary tumors (15%)(p<0.001). Conclusions: ChemoFx response rates to PC are consistent with expected population response rates. As anticipated, more aggressive histologic subtypes were less responsive to CP in vitro. These data suggest that the ChemoFx assay provides tumor-specific information that may assist in chemotherapy decision making.

Dual-console robotic surgery compared to laparoscopic surgery with respect to surgical outcomes in a gynecologic oncology fellowship program

OBJECTIVE

Minimally invasive surgical techniques decrease surgical morbidity and recovery time. Studies demonstrate similar surgical outcomes comparing robotic to laparoscopic surgery. These studies have not accounted for the incorporation of fellow education. With the dual-console da Vinci Si Surgical System®, a two surgeon approach could be performed. We sought to compare surgical outcomes at a gynecologic oncology fellowship program of traditional laparoscopic to robotic surgeries using the dual-console system.

METHODS

We identified patients who underwent laparoscopic or robotic surgery performed by a gynecologic oncologist from November 2009-November 2010. Robotic surgeries were conducted using the dual-console, utilizing a two surgeon approach. Surgeries involved a staff physician with a gynecologic oncology fellow. Statistical analysis was performed using student t-test and chi-squared analysis.

RESULTS

A total of 222 cases were identified. Cases were analyzed in groups: all cases identified, all cancer cases, and endometrial cancer cases only. When analyzing all cases, no statistical difference was noted in total operating room time (172 vs. 175 min; p=0.6), pelvic lymph nodes removed (10.1 vs. 9.6; p=0.69), para-aortic lymph nodes dissected (3.7 vs. 3.8; p=0.91), or length of stay (1.5 vs. 1.3 days; p=0.3). There was a significant difference in total surgical time (131 vs.110 min; p<0.0001) and EBL (157 vs.94 ml; p<0.0001), favoring robotic surgery. When analyzing all cancer cases, the advantage in total surgical time for robotic surgery was lost. Complications were similar between cohorts.

CONCLUSION

Incorporating fellow education into robotic surgery does not adversely affect outcomes when compared to traditional laparoscopic surgery.

Comparison of ERCC1/XPF genetic variation, mRNA and protein levels in women with advanced stage ovarian cancer treated with intraperitoneal platinum

OBJECTIVE

Approximately 20% of patients receiving platinum-based chemotherapy for epithelial ovarian cancer (EOC) are refractory or develop early recurrence. Identifying these patients early could reduce treatment-associated morbidity and allow quicker transfer to more effective therapies. Much attention has focused on ERCC1 as a potential predictor of response to therapy because of its essential role in the repair of platinum-induced DNA damage. The purpose of this study was to accurately measure protein levels of ERCC1 and its essential binding partner XPF from patients with EOC treated with platinum-based therapy and determine if protein levels correlate with mRNA levels, patient genotypes or clinical outcomes.

METHODS

ERCC1 and XPF mRNA and protein levels were measured in frozen EOC specimens from 41 patients receiving intraperitoneal platinum-based chemotherapy using reverse transcription polymerase chain reaction and western blots. Genotypes of common nucleotide polymorphisms were also analyzed. Patient outcomes included progression free (PFS) and overall survival (OS).

RESULTS

Expression of ERCC1 and XPF were tightly correlated with one another at both the mRNA and protein level. However, the mRNA and protein levels of ERCC1 were not positively correlated. Likewise, none of the SNPs analyzed correlated with ERCC1 or XPF protein levels. There was an inverse correlation between mRNA levels and patient outcomes.

CONCLUSION

Neither genotype nor mRNA levels are predictive of protein expression. Despite this, low ERCC1 mRNA significantly correlated with improved PFS and OS.

Abstract 3116: Patterns of genomic loss of heterozygosity predict homologous recombination repair defects in ovarian cancer

Introduction: BRCA1 and BRCA2 are key members of the homologous recombination (HR) pathway. Mutations in these genes and other HR pathway defects have potential therapeutic relevance when used to support agents that introduce or exploit double-strand DNA breaks. This study examines the association between HR deficiency and genomic patterns of loss of heterozygosity (LOH). Methods: Ovarian tumors from two independent datasets were characterized for germline and somatic defects in BRCA1 and BRCA2. Whole genome LOH profiles were generated using Affymetrix SNP arrays. Publically available data was downloaded from the TCGA website for a third independent ovarian cancer dataset. RAD51C promoter methylation was assayed in two of the datasets. Comprehensive profiling of BRCA1 and BRCA2 defects, and genome wide LOH was also performed on approximately 70 breast, ovarian, colon and pancreatic cell lines. Results: Examination of the pattern of LOH within ovarian tumors with BRCA1, BRCA2, or RAD51C defects compared to tumors without defects in these genes has resulted in the development of a homologous recombination deficiency (HRD) score that has highly significant association with HRD (p=9*10-11). An intermediate class of LOH sizes (&gt;15 Mb but less than a whole chromosome) is highly positive correlated with defective HR, suggesting this class of LOH exists due to double strand DNA break formation and requires repair by HR. The HRD score was validated in two independent ovarian cancer datasets (p=2*10-7 and 9*10-29), and successfully identified breast and pancreatic cell lines with BRCA defects, suggesting it will be effective across multiple tumor types. Conclusions: BRCA1 or BRCA2 mutation carriers have improved outcomes following treatment with DNA damaging agents such as platinum salts, and preclinical studies have demonstrated PARP inhibitor efficacy in BRCA1 or BRCA2 deficient cells. HR deficiency in ovarian cancer is not solely due to germline BRCA1 and BRCA2 mutations, and HR deficiency is not unique to ovarian tumors. Each type of cancer is likely to have a unique spectrum of genetic variants resulting in HRD. The HRD score appears capable of detecting HRD regardless of etiology or mechanism. This score could have clinical utility in breast and ovarian cancer, and could be used to target the use of PARP inhibitors and platinum salts in other cancers.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3116. doi:1538-7445.AM2012-3116

Dual-console robotic surgery: a new teaching paradigm

Robotic surgery has emerged as an alternative option in minimally invasive gynecologic surgery. The development of the dual-console da Vinci Si Surgical System(®) has enabled modification of the training atmosphere. We sought to investigate operative times and surgical outcomes while operating with the dual-console model in a training environment for our first fifty cases. We identified the first fifty patients who underwent robot-assisted total hysterectomy (TRH), with or without bilateral salpingo-oophorectomy (BSO), with or without pelvic and para-aortic lymph node dissection (PPALND), by use of the dual-console robotic system. Records were reviewed for patient demographics and surgical details. All surgery was conducted using the dual-console system and performed by staff physicians and fellows. Operative time was calculated from robotic docking until completion of the procedure. Cases were identified from November 2009 through July 2010. Mean age was 56.2 years (SD 13.35, 95 % CI 52.46-59.86). Mean BMI was 29.5 (SD 7.67, 95 % CI 27.35-31.61). Seventy-eight percent of these patients were considered overweight, including 12 defined as obese (BMI 30-34.9) and 10 patients classified as morbidly obese (BMI ≥ 35). Surgery completed included PPALND alone (n = 1); radical hysterectomy (n = 1); TRH only (n = 3); TRH/BSO (n = 25); and TRH/BSO/PPALND (n = 20). Mean total operating room time was 188.8 min (SD 55.31, 95 % CI 173.45-204.11). Mean total surgical time for all cases was 118.1 min (SD 44.28, 95 % CI 105.87-130.41). Two vascular injuries were encountered, with one requiring conversion to laparotomy. These results compare favorably with historically reported outcomes from single-console systems. Utilizing the dual-console enables use of an integrated teaching and supervising environment without compromising operative times or patient outcomes.

Differential analysis of ovarian and endometrial cancers identifies a methylator phenotype

Despite improved outcomes in the past 30 years, less than half of all women diagnosed with epithelial ovarian cancer live five years beyond their diagnosis. Although typically treated as a single disease, epithelial ovarian cancer includes several distinct histological subtypes, such as papillary serous and endometrioid carcinomas. To address whether the morphological differences seen in these carcinomas represent distinct characteristics at the molecular level we analyzed DNA methylation patterns in 11 papillary serous tumors, 9 endometrioid ovarian tumors, 4 normal fallopian tube samples and 6 normal endometrial tissues, plus 8 normal fallopian tube and 4 serous samples from TCGA. For comparison within the endometrioid subtype we added 6 primary uterine endometrioid tumors and 5 endometrioid metastases from uterus to ovary. Data was obtained from 27,578 CpG dinucleotides occurring in or near promoter regions of 14,495 genes. We identified 36 locations with significant increases or decreases in methylation in comparisons of serous tumors and normal fallopian tube samples. Moreover, unsupervised clustering techniques applied to all samples showed three major profiles comprising mostly normal samples, serous tumors, and endometrioid tumors including ovarian, uterine and metastatic origins. The clustering analysis identified 60 differentially methylated sites between the serous group and the normal group. An unrelated set of 25 serous tumors validated the reproducibility of the methylation patterns. In contrast, >1,000 genes were differentially methylated between endometrioid tumors and normal samples. This finding is consistent with a generalized regulatory disruption caused by a methylator phenotype. Through DNA methylation analyses we have identified genes with known roles in ovarian carcinoma etiology, whereas pathway analyses provided biological insight to the role of novel genes. Our finding of differences between serous and endometrioid ovarian tumors indicates that intervention strategies could be developed to specifically address subtypes of epithelial ovarian cancer.

Heavy cervical cancer burden in elderly women: how can we improve the situation?

OBJECTIVES

The American Cancer Society, the American College of Obstetricians and Gynecologists and the US Preventive Services Task Force recommend discontinuation of cervical cancer screening between 65 and 70 years of age in women with no abnormal test results in the preceding 10 years. This population-based study was undertaken to determine the incidence of cervical cancer in different age groups as a means to establish if current screening recommendations need reevaluation.

STUDY DESIGN

Data from the SEER database were used to compute incidence rates for cervical cancer diagnosed between 2000 and 2006 by age and disease stage.

RESULTS

We identified 18,003 women with cervical cancer. 12.18% were above the age of 69. The incidence in this age group was 8.7/100,000. Women younger than 30 comprised 5.7% of patients with an incidence of 5/100,000 and were most commonly diagnosed with stage IA1 disease. Women above 70 were most frequently diagnosed with stage IIIB. 79% of patients younger than 30 were diagnosed with an early disease (stage IA1-IIA) as opposed to only 41.2% of patients aged 69 or above.

CONCLUSIONS

The incidence of cervical cancer does not decrease significantly in older women. Women over the age of 70 are frequently diagnosed with advanced stage disease which limits their treatment options. Failure to apply uniform screening across all at-risk age groups may account for the discrepancy.

Common variants in ABCB1, ABCC2 and ABCG2 genes and clinical outcomes among women with advanced stage ovarian cancer treated with platinum and taxane-based chemotherapy: a Gynecologic Oncology Group study

PURPOSE

Efflux transporters of the ATP-binding cassette (ABC) family are major determinants of chemoresistance in tumor cells. This study examined associations between functional variants in ABCB1, ABCC2 and ABCG2 genes and clinical outcomes in patients with epithelial ovarian/primary peritoneal cancer (EOC/PPC) following platinum and taxane-based chemotherapy.

METHODS

Sequenom iPLEXTMGOLD Assay and MALDI-TOF platform were used to genotype the non-synonymous G2677T/A (rs2032582; encoding Ala893Ser/Thr) and synonymous C3435T (rs1045642; encoding Ile1145Ile) variants in ABCB1, the non-synonymous G1249A variant in ABCC2 (rs2273697; encoding Val417Ile), and the non-synonymous C421A variant in ABCG2 (rs2231142; encoding Q141K, Gln141Lys) in normal DNA from up to 511 women in Gynecologic Oncology Group (GOG) phase III trials, GOG-172 or GOG-182. Progression-free survival (PFS) and overall survival (OS) were analyzed in relation to genetic polymorphisms using Kaplan-Meier and Cox proportional hazards model.

RESULTS

The C421A variant (CA+AA versus CC) in ABCG2 was associated with a 6-month longer median PFS (22.7 versus 16.8 months, p=0.041). In multivariate analysis, patients with variant genotypes were at a reduced risk of disease progression (hazard ratio [HR]=0.75, 95% confidence interval [CI]=0.59-0.96, p=0.022). The association between C421A and OS was not statistically significant (HR=0.88, 95% CI=0.67-1.15, p=0.356). None of the other variants measured in either ABCB1 or ABCC2 was associated with PFS or OS.

CONCLUSION

The C421A variant in ABCG2, previously shown to be associated with enhanced protein degradation and drug sensitivity, was associated with longer PFS in advanced stage EOC/PPC patents treated with platinum+taxane-based chemotherapy. This finding requires further validation.

Should stage IIIC ovarian cancer be further stratified by intraperitoneal vs. retroperitoneal only disease?: a Gynecologic Oncology Group study

OBJECTIVE

To examine whether clinical outcomes varied with intraperitoneal (IP) and/or retroperitoneal (RP) involvement in stage IIIC epithelial ovarian cancer (EOC) patients with microscopic residual disease after cytoreduction.

METHODS

Retrospective review was performed for EOC patients enrolled in Gynecologic Oncology Group (GOG)-182 who underwent primary cytoreduction to microscopic residual disease. Patients were divided into 3 groups: stage IIIC by lymphadenopathy with <2 cm IP spread (RP); >2 cm IP spread and negative nodes (IP/RP-); and >2 cm IP dissemination and positive lymphadenopathy (IP/RP+). Product-limit and multivariate proportional hazards modeling were used.

RESULTS

Analyses included 417 stage IIIC women who underwent primary cytoreduction with lymphadenectomy to microscopic residual. There were 203, 123, and 91 in the RP, IP/RP-, and IP/RP+ groups, respectively. IP/RP+ and IP/RP- were associated with worse progression-free survival (PFS) (Hazard Ratio (HR) 1.68, 95% confidence interval (CI) 1.23-2.30; HR 1.38, 95% CI 1.04-1.84) vs. RP only. IP/RP+ was associated with worse overall survival (OS) (HR 1.79, 95% CI 1.24-2.57) while IP/RP- trended towards worse OS (HR 1.21, 95% CI 0.85-1.73) vs. RP only. Median PFS for IP/RP+ and IP/RP- groups was 21 and 29 months, respectively, vs. 48 months in the RP group (p=0.0007) and median OS of 63 and 79 months vs. "not reached," respectively (p=0.0038).

CONCLUSIONS

Among EOC patients surgically cytoreduced to microscopic residual disease, those upstaged to IIIC by retroperitoneal involvement demonstrated significant improvement in PFS and OS compared to patients with intraperitoneal tumor, suggesting that these women may represent a unique subset of FIGO stage IIIC patients.

Consolidation paclitaxel is more cost-effective than bevacizumab following upfront treatment of advanced epithelial ovarian cancer

INTRODUCTION

Randomized trials have demonstrated significant improvements in progression-free survival (PFS) with consolidation paclitaxel (P) and bevacizumab (B) following cytoreduction and adjuvant carboplatin/paclitaxel (CP) for advanced epithelial ovarian cancer (EOC). We sought to evaluate the cost-effectiveness (C/E) of these consolidation strategies.

METHODS

A decision model was developed based on Gynecologic Oncology Group (GOG) protocols #178 and #218. Arm 1 is 6 cycles of CP. Arm 2 is 6 cycles of CP followed by 12 cycles of P (CP+P). Arm 3 is 1 cycle of CP, 5 cycles of CPB, and 16 cycles of B (CPB+B). Parameters include PFS, overall survival (OS), cost, complications (neuropathy for P and bowel perforation for B), and quality-of-life utility values. Sensitivity analyses were performed.

RESULTS

The incremental cost-effectiveness ratio (ICER) for CT+T is $13,402/quality adjusted life year (QALY) gained compared to CP. For CPB+B compared to CP, the ICER is $326,530/QALY. When compared simultaneously, CPB+B is dominated, i.e. is more costly and less effective than CP+P. Results were robust to parameter variation. At a willingness to pay threshold of $100,000/QALY, CP+P was the preferred option throughout most of the decision space. Sensitivity analyses suggest that CPB+B would become the preferred option if it were to improve OS by 6.1 years over CP+P.

CONCLUSIONS

In this model, B consolidation for advanced EOC was associated with a modest improvement in effectiveness that is less than that with P consolidation and more costly. A statistically significant improvement in survival may improve the value of B consolidation.

The impact of disease distribution on survival in patients with stage III epithelial ovarian cancer cytoreduced to microscopic residual: a Gynecologic Oncology Group study

OBJECTIVE

To assess the survival impact of initial disease distribution on patients with stage III epithelial ovarian cancer (EOC) cytoreduced to microscopic residual.

METHODS

We reviewed data from 417 stage III EOC patients cytoreduced to microscopic disease and given adjuvant intravenous platinum/paclitaxel on one of three randomized Gynecologic Oncology Group (GOG) trials. We subdivided patients into three groups based on preoperative disease burden: (1) minimal disease (MD) defined by pelvic tumor and retroperitoneal metastasis (2) abdominal peritoneal disease (APD) with disease limited to the pelvis, retroperitoneum, lower abdomen and omentum; and (3) upper abdominal disease (UAD) with disease affecting the diaphragm, spleen, liver or pancreas. We assessed the survival impact of potential prognostic factors, focusing on initial disease distribution using a proportional hazards model and estimated Kaplan-Meier survival curves.

RESULTS

The study groups had similar clinicopathologic characteristics. Median overall survival (OS) was not reached in MD patients compared to 80 and 56 months in the APD and UAD groups (P<0.05). The five-year survival percentages for MD, APD, and UAD were 67%, 63%, and 45%. In multivariate analysis, the UAD group had a significantly worse prognosis than MD and APD both individually and combined (Progression Free Survival (PFS) Hazards Ratio (HR) 1.44; P=0.008 and OS HR 1.77; P=0.0004 compared to MD+APD).

CONCLUSION

Stage III EOC patients with initial disease in the upper abdomen have a worse prognosis despite cytoreductive surgery to microscopic residual implying that factors beyond cytoreductive effort are important in predicting survival.