Thomas C. Krivak

Patterns of genomic loss of heterozygosity predict homologous recombination repair defects in epithelial ovarian cancer

Background:Defects in BRCA1, BRCA2, and other members of the homologous recombination pathway have potential therapeutic relevance when used to support agents that introduce or exploit double-stranded DNA breaks. This study examines the association between homologous recombination defects and genomic patterns of loss of heterozygosity (LOH).Methods:Ovarian tumours from two independent data sets were characterised for defects in BRCA1, BRCA2, and RAD51C, and LOH profiles were generated. Publically available data were downloaded for a third independent data set. The same analyses were performed on 57 cancer cell lines.Results:Loss of heterozygosity regions of intermediate size were observed more frequently in tumours with defective BRCA1 or BRCA2 (P=10−11). The homologous recombination deficiency (HRD) score was defined as the number of these regions observed in a tumour sample. The association between HRD score and BRCA deficiency was validated in two independent ovarian cancer data sets (P=10−5 and 10−29), and identified breast and pancreatic cell lines with BRCA defects.Conclusion:The HRD score appears capable of detecting homologous recombination defects regardless of aetiology or mechanism. This score could facilitate the use of PARP inhibitors and platinum in breast, ovarian, and other cancers.

Does Aggressive Surgery Improve Outcomes? Interaction Between Preoperative Disease Burden and Complex Surgery in Patients With Advanced-Stage Ovarian Cancer: An Analysis of GOG 182

PURPOSE To examine the effects of disease burden, complex surgery, and residual disease (RD) status on progression-free (PFS) and overall survival (OS) in patients with advanced epithelial ovarian cancer (EOC) or primary peritoneal cancer (PPC) and complete surgical resection (R0) or < 1 cm of RD (MR) after surgical cytoreduction. PATIENTS AND METHODS Demographic, pathologic, surgical, and outcome data were collected from 2,655 patients with EOC or PPC enrolled onto the Gynecologic Oncology Group 182 study. The effects of disease distribution (disease score [DS]) and complexity of surgery (complexity score [CS]) on PFS and OS were assessed using the Kaplan-Meier method and multivariable regression analysis. RESULTS Consistent with existing literature, patients with MR had worse prognosis than R0 patients (PFS, 15 v 29 months; P < .01; OS, 41 v 77 months; P < .01). Patients with the highest preoperative disease burden (DS high) had shorter PFS (15 v 23 or 34 months; P < .01) and OS (40 v 71 or 86 months; P < .01) compared with those with DS moderate or low, respectively. This relationship was maintained in the subset of R0 patients with PFS (18.3 v 33.2 months; DS moderate or low: P < .001) and OS (50.1 v 82.8 months; DS moderate or low: P < .001). After controlling for DS, RD, an interaction term for DS/CS, performance status, age, and cell type, CS was not an independent predictor of either PFS or OS. CONCLUSION In this large multi-institutional sample, initial disease burden remained a significant prognostic indicator despite R0. Complex surgery does not seem to affect survival when accounting for other confounding influences, particularly RD.

Relationship Between ERCC1 Polymorphisms, Disease Progression, and Survival in the Gynecologic Oncology Group Phase III Trial of Intraperitoneal Versus Intravenous Cisplatin and Paclitaxel for Stage III Epithelial Ovarian Cancer

PURPOSE We hypothesized that common polymorphisms in excision repair cross-complementation group 1 (ERCC1), involved in nucleotide excision repair of platinum-induced damage, would be associated with progression-free survival (PFS) and overall survival (OS) in women with optimally resected, stage III epithelial ovarian cancer (EOC) treated with cisplatin and paclitaxel (C+P). PATIENTS AND METHODS Single nucleotide polymorphism analysis was carried out by direct pyrosequencing at two sites (codon 118 and C8092A) in ERCC1 in leukocyte DNA from women who participated in the Gynecologic Oncology Group (GOG) phase III protocol-172 and were randomly assigned to intraperitoneal or intravenous C+P. RESULTS ERCC1 genotyping was performed in 233 of the 429 women who participated in GOG-172. The genotype distribution at codon 118 was 17% with C/C, 43% with C/T, and 40% with T/T, and the genotype distribution at C8092A was 56% with C/C, 37% with C/A, and 7% with A/A. Adjusted Cox regression analysis revealed that the codon 118 polymorphism in ERCC1 was not significantly associated with disease progression or death. Women with the C8092A C/A or A/A genotypes compared with the C/C genotype had an increased risk of disease progression (hazard ratio [HR] = 1.44; 95% CI, 1.06 to 1.94; P = .018) and death (HR = 1.50; 95% CI, 1.07 to 2.09; P = .018). Median PFS and OS were 6 and 17 months shorter for women with the C8092A C/A or A/A genotypes versus the C/C genotype, respectively. CONCLUSION Although the ERCC1 codon 118 polymorphism does not seem to be associated with clinical outcome, the C8092A polymorphism was an independent predictor of PFS and OS in women with optimally resected EOC.

BRCA1 expression and improved survival in ovarian cancer patients treated with intraperitoneal cisplatin and paclitaxel: a Gynecologic Oncology Group Study

Background:Breast cancer 1, early onset (BRCA1) is a tumour-suppressor gene associated with familial epithelial ovarian cancer (EOC). Reduced BRCA1 expression is associated with enhanced sensitivity to platinum-based chemotherapy. We sought to examine the prognostic relevance of BRCA1 expression in EOC patients treated with intraperitoneal platinum/taxane.Methods:The GOG-172 was a phase III, multi-institutional randomised trial of intravenous paclitaxel and cisplatin (IV therapy) vs intravenous paclitaxel, intraperitoneal cisplatin plus paclitaxel (IP therapy) in patients with optimally resected stage III EOC. The BRCA1 expression was assessed with immunohistochemistry (IHC) staining blinded to clinical outcome in archival tumour specimens. Slides with ⩽10% staining were defined as aberrant and >10% as normal. Correlations between BRCA1 expression and progression-free survival (PFS) and overall survival (OS) were analysed using Kaplan–Meier method and Cox regression analysis.Results:Of the 393 patients, 189 tumours had aberrant expression, and 204 had normal BRCA1 expression. There was an interaction between BRCA1 expression and route of administration on OS (P=0.014) but not PFS (P=0.054). In tumours with normal BRCA1 expression, the median OS was 58 months for IP group vs 50 months for IV group (P=0.818). In tumours with aberrant BRCA1 expression, the median OS was 84 vs 47 months in the IP vs IV group, respectively (P=0.0002). Aberrant BRCA1 expression was an independent prognostic factor for better survival in women randomised to IP therapy (hazard ratio (HR)=0.67, 95% confidence interval (CI)=0.47–0.97, P=0.032). Similar survival was observed in the IV and IP patients with normal BRCA1 expression. Multivariate but not univariate modelling demonstrated that IV patients with aberrant vs normal BRCA1 expression had worse survival.Conclusion:Decreased BRCA1 expression is associated with a 36-month survival improvement in patients with EOC treated with IP chemotherapy. Although these results merit validation in future studies, the results suggest that decreased BRCA1 expression predicts for improved response to cisplatin-based IP chemotherapy with cisplatin and paclitaxel.

BRCA1/2 mutations and expression: Response to platinum chemotherapy in patients with advanced stage epithelial ovarian cancer

OBJECTIVE Our objective was to determine the rate of BRCA1/2 deficiency in platinum-sensitive and platinum-resistant tumors from a cohort of unselect patients with advanced epithelial ovarian cancer (EOH). METHODS BRCA1/2 mutation analysis was performed in 29 patients with platinum-sensitive EOC and 24 patients with platinum-resistant disease. Germline DNA was analyzed in mutation carriers when normal tissue was available. BRCA expression was ascertained by quantitative rt-PCR. Associations between BRCA mutation status and expression levels and parameters of platinum response were analyzed. RESULTS Fifteen of 53 (28.3%) EOC tumors had BRCA1/2 mutations. Twelve mutations were in BRCA1, while 3 involved BRCA2. Of the 12 mutation-carriers with normal tissue available for DNA analyses, 33.3% of the mutations were found to be somatic. Three mutations were novel. The majority of BRCA mutations (73%) were identified in patients with platinum-sensitive disease. In total, 38% of platinum-sensitive tumors were found to have a BRCA mutation, compared to 17% of the platinum-resistant patients. A statistical trend toward platinum-sensitive disease was seen in BRCA mutation carriers (p=0.079). Nineteen (36%) study patients had some form of BRCA deficiency, and these patients were less likely to have platinum-resistant tumors (OR=0.29; p value=0.048). CONCLUSIONS BRCA mutations occurred more frequently in platinum-sensitive EOC than platinum-resistant disease. The high overall frequency of BRCA deficiency in EOC underscores the importance of tumor profiling as therapies targeting the DNA repair pathway are being investigated.

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.

Preoperative intensity-modulated radiotherapy and chemotherapy for locally advanced vulvar carcinoma

OBJECTIVE Intensity-modulated radiation therapy (IMRT) is a rapidly maturing technology that allows delivery of radiation dose in a more conformal manner by varying the radiation beams spatially or temporally. The purpose of the study was to assess the clinical outcome in patients with locally-advanced vulvar cancers treated using preoperative chemotherapy with IMRT. METHODS Eighteen patients with stage II-IVA cancer were treated with a modified GOG schema using 5-fluorouracil (5-FU) and cisplatin with twice-daily (BID) IMRT during the first and last weeks of treatment. Surgery was planned for 6-8 weeks post-treatment. RESULTS The median follow-up time was 22 months (2-60 months). Fourteen patients had surgery performed with pathological complete response (pCR) in 9 (64%) patients and partial response (pPR) in 5 patients. There were no recurrences in the 9 patients who achieved pCR whereas 3/5 with pPR had local recurrence (p=0.027). Four patients did not have surgery: one patient died a week after treatment while 2 of the remaining 3 patients had local recurrences. Acute desquamative skin reactions in the vulva and perineum were seen in all patients. Three of the 14 patients who had surgery had prolonged wound complications requiring debridement. No patients had radiation-related acute or late toxicity of grade = 3. The 2-year cause specific and overall survivals were 75% and 70% respectively. CONCLUSION Preoperative chemotherapy and IMRT were well tolerated with good clinical response and early clinical outcome. Pathological complete response predicts better outcomes. Prospective clinical trials with sufficient patient numbers and follow-up are needed to determine the true impact of IMRT in these patients.

Venous thromboembolism in obstetrics and gynecology.

The diagnosis of venous thromboembolism can present a clinical challenge. Using D-dimer testing and spiral or helical computed tomography scans has simplified the diagnosis of venous thromboembolism. In addition, the use of low molecular weight heparin has become widely accepted in the prevention and treatment of venous thromboembolism. However, further studies are needed to determine optimal prevention and treatment strategies, particularly in the obstetric population.

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.

Three-dimensional High Dose Rate Intracavitary Image-guided Brachytherapy for the Treatment of Cervical Cancer Using a Hybrid Magnetic Resonance Imaging/Computed Tomography Approach: Feasibility and Early Results

AIMS To evaluate the feasibility and outcome of image-guided brachytherapy (IGBT) for treating cervical cancer using magnetic resonance imaging (MRI)-based planning for the first fraction followed by computed tomography (CT)-based planning for subsequent fractions. MATERIALS AND METHODS Forty-four patients with cervical cancer were treated with three-dimensional high dose rate IGBT. The brachytherapy dose was 5.0-6.0 Gy × five fractions. All but five patients received concurrent weekly cisplatinum at 40 mg/m(2). All patients received external beam radiotherapy (EBRT) with a median dose of 45Gy over 25 fractions. Total doses for the high-risk clinical target volume (HRCTV) and organs at risk, including the rectum, bladder and sigmoid, from EBRT and brachytherapy were summated and normalised to a biologically equivalent dose of 2Gy per fraction (EQD(2)). At 3 months after therapy, any early response was assessed with positron emission tomography (PET)/CT imaging. RESULTS The mean D(90) for the HRCTV was 83.3 (3.0) Gy. The mean 2 cm (3) dose to the bladder, rectum and sigmoid colon organs was 79.7 (5.1), 57.5 (4.4) and 66.8 (5.7) Gy, respectively. All but one (2.3%) patient had a complete response. Follow-up PET/CT was carried out in 41 (93.0%) patients, of whom 38 (92.5%) had a complete response. Of the 38 patients with a complete response on PET/CT, two had local recurrences at 6 and 8 months, respectively. Actuarial 2 year local control, disease-specific and overall survival rates were 88, 85 and 86%, respectively. CONCLUSION This is the first report of three-dimensional high dose rate IGBT for the treatment of cervical cancer using a hybrid MRI/CT approach. Early results have shown the feasibility of this approach with excellent local control. Additional studies are needed to assess long-term outcomes of local control and associated morbidities.