HER2 overexpression and amplification is present in a subset of ovarian mucinous carcinomas and can be targeted with trastuzumab therapy

<p>Abstract</p> <p>Background</p> <p>The response rate of ovarian mucinous carcinomas to paclitaxel/carboplatin is low, prompting interest in targeted molecular therapies. We investigated HER2 expression and amplification, and the potential for trastuzumab therapy in this histologic subtype of ovarian cancer.</p> <p>Methods</p> <p>HER2 status was tested in 33 mucinous carcinomas and 16 mucinous borderline ovarian tumors (BOT)). Five cases with documented recurrence and with tissue from the recurrence available for testing were analyzed to determine whether HER2 amplification status changed over time. Three prospectively identified recurrent mucinous ovarian carcinomas were assessed for HER2 amplification and patients received trastuzumab therapy with conventional chemotherapy.</p> <p>Results</p> <p>Amplification of HER2 was observed in 6/33 (18.2%) mucinous carcinomas and 3/16 (18.8%) BOT. HER2 amplification in primary mucinous carcinomas was not associated with an increased likelihood of recurrence. The prospectively identified recurrent mucinous carcinomas showed overexpression and amplification of HER2; one patient's tumor responded dramatically to trastuzumab in combination with conventional chemotherapy, while another patient experienced an isolated central nervous system recurrence after trastuzumab therapy.</p> <p>Conclusion</p> <p>HER2 amplification is relatively common in ovarian mucinous carcinomas (6/33, 18.2%), although not of prognostic significance. Trastuzumab therapy is a treatment option for patients with mucinous carcinoma when the tumor has HER2 amplification and overexpression.</p

Genome-wide association study of subtype-specific epithelial ovarian cancer risk alleles using pooled DNA

Epithelial ovarian cancer (EOC) is a heterogeneous cancer with both genetic and environmental risk factors. Variants influencing the risk of developing the less-common EOC subtypes have not been fully investigated. We performed a genome-wide association study (GWAS) of EOC according to subtype by pooling genomic DNA from 545 cases and 398 controls of European descent, and testing for allelic associations. We evaluated for replication 188 variants from the GWAS [56 variants for mucinous, 55 for endometrioid and clear cell, 53 for low-malignant potential (LMP) serous, and 24 for invasive serous EOC], selected using pre-defined criteria. Genotypes from 13,188 cases and 23,164 controls of European descent were used to perform unconditional logistic regression under the log-additive genetic model; odds ratios (OR) and 95 % confidence intervals are reported. Nine variants tagging six loci were associated with subtype-specific EOC risk at P < 0.05, and had an OR that agreed in direction of effect with the GWAS results. Several of these variants are in or near genes with a biological rationale for conferring EOC risk, including ZFP36L1 and RAD51B for mucinous EOC (rs17106154, OR = 1.17, P = 0.029, n = 1,483 cases), GRB10 for endometrioid and clear cell EOC (rs2190503, P = 0.014, n = 2,903 cases), and C22orf26/BPIL2 for LMP serous EOC (rs9609538, OR = 0.86, P = 0.0043, n = 892 cases). In analyses that included the 75 GWAS samples, the association between rs9609538 (OR = 0.84, P = 0.0007) and LMP serous EOC risk remained statistically significant at P < 0.0012 adjusted for multiple testing. Replication in additional samples will be important to verify these results for the less-common EOC subtypes

Genome-wide association study of subtype-specific epithelial ovarian cancer risk alleles using pooled DNA.

Epithelial ovarian cancer (EOC) is a heterogeneous cancer with both genetic and environmental risk factors. Variants influencing the risk of developing the less-common EOC subtypes have not been fully investigated. We performed a genome-wide association study (GWAS) of EOC according to subtype by pooling genomic DNA from 545 cases and 398 controls of European descent, and testing for allelic associations. We evaluated for replication 188 variants from the GWAS [56 variants for mucinous, 55 for endometrioid and clear cell, 53 for low-malignant potential (LMP) serous, and 24 for invasive serous EOC], selected using pre-defined criteria. Genotypes from 13,188 cases and 23,164 controls of European descent were used to perform unconditional logistic regression under the log-additive genetic model; odds ratios (OR) and 95&nbsp;% confidence intervals are reported. Nine variants tagging six loci were associated with subtype-specific EOC risk at P&nbsp;&lt;&nbsp;0.05, and had an OR that agreed in direction of effect with the GWAS results. Several of these variants are in or near genes with a biological rationale for conferring EOC risk, including ZFP36L1 and RAD51B for mucinous EOC (rs17106154, OR&nbsp;=&nbsp;1.17, P&nbsp;=&nbsp;0.029, n&nbsp;=&nbsp;1,483 cases), GRB10 for endometrioid and clear cell EOC (rs2190503, P&nbsp;=&nbsp;0.014, n&nbsp;=&nbsp;2,903 cases), and C22orf26/BPIL2 for LMP serous EOC (rs9609538, OR&nbsp;=&nbsp;0.86, P&nbsp;=&nbsp;0.0043, n&nbsp;=&nbsp;892 cases). In analyses that included the 75 GWAS samples, the association between rs9609538 (OR&nbsp;=&nbsp;0.84, P&nbsp;=&nbsp;0.0007) and LMP serous EOC risk remained statistically significant at P&nbsp;&lt;&nbsp;0.0012 adjusted for multiple testing. Replication in additional samples will be important to verify these results for the less-common EOC subtypes

Genome-wide association study of subtype-specific epithelial ovarian cancer risk alleles using pooled DNA.

Epithelial ovarian cancer (EOC) is a heterogeneous cancer with both genetic and environmental risk factors. Variants influencing the risk of developing the less-common EOC subtypes have not been fully investigated. We performed a genome-wide association study (GWAS) of EOC according to subtype by pooling genomic DNA from 545 cases and 398 controls of European descent, and testing for allelic associations. We evaluated for replication 188 variants from the GWAS [56 variants for mucinous, 55 for endometrioid and clear cell, 53 for low-malignant potential (LMP) serous, and 24 for invasive serous EOC], selected using pre-defined criteria. Genotypes from 13,188 cases and 23,164 controls of European descent were used to perform unconditional logistic regression under the log-additive genetic model; odds ratios (OR) and 95&nbsp;% confidence intervals are reported. Nine variants tagging six loci were associated with subtype-specific EOC risk at P&nbsp;&lt;&nbsp;0.05, and had an OR that agreed in direction of effect with the GWAS results. Several of these variants are in or near genes with a biological rationale for conferring EOC risk, including ZFP36L1 and RAD51B for mucinous EOC (rs17106154, OR&nbsp;=&nbsp;1.17, P&nbsp;=&nbsp;0.029, n&nbsp;=&nbsp;1,483 cases), GRB10 for endometrioid and clear cell EOC (rs2190503, P&nbsp;=&nbsp;0.014, n&nbsp;=&nbsp;2,903 cases), and C22orf26/BPIL2 for LMP serous EOC (rs9609538, OR&nbsp;=&nbsp;0.86, P&nbsp;=&nbsp;0.0043, n&nbsp;=&nbsp;892 cases). In analyses that included the 75 GWAS samples, the association between rs9609538 (OR&nbsp;=&nbsp;0.84, P&nbsp;=&nbsp;0.0007) and LMP serous EOC risk remained statistically significant at P&nbsp;&lt;&nbsp;0.0012 adjusted for multiple testing. Replication in additional samples will be important to verify these results for the less-common EOC subtypes