Neoadjuvant paclitaxel/olaparib in comparison to paclitaxel/carboplatinum in patients with HER2-negative breast cancer and homologous recombination deficiency (GeparOLA study).

BACKGROUND: The efficacy and toxicity of olaparib as combination therapy in early breast cancer (BC) patients with homologous recombinant deficiency (HRD) [score high and/or germline (g) or tumour (t) BRCA1/2 mutation] is not well described. GeparOLA (ClinicalTrials.gov, NCT02789332) investigated olaparib in combination with paclitaxel in HER2-negative early BC with HRD. PATIENTS AND METHODS: Patients with untreated primary HER2-negative cT2-cT4a-d or cT1c with either cN+ or pNSLN+ or cT1c and triple-negative breast cancer (TNBC) or cT1c and Ki-67>20% BC with HRD were randomised either to paclitaxel (P) 80 mg/m2 weekly plus olaparib (O) 100 mg twice daily for 12 weeks or P plus carboplatinum (Cb) area under the curve 2 weekly for 12 weeks, both followed by epirubicin/cyclophosphamide (EC). Stratification factors were hormone receptor (HR) status (HR+ versus HR-) and age (<40 versus ≥40 years). The primary endpoint was pathological complete response (pCR; ypT0/is ypN0). A two-sided one-group χ2-test was planned to exclude a pCR rate of ≤55% in the PO-EC arm. Secondary end points were other pCR definitions, breast conservation rate, clinical/imaging response, tolerability and safety. RESULTS: A total of 107 patients were randomised between September 2016 and July 2018; 106 (PO N = 69; PCb N = 37) started treatment. Median age was 47.0 years (range 25.0-71.0); 36.2% had cT1, 61.0% cT2, 2.9% cT3, and 31.8% cN-positive tumours; grade 3 tumours: 86.8%; Ki-67>20%: 89.6%; TNBC: 72.6%; confirmed gBRCA1/2 mutation: 56.2%. The pCR rate with PO was 55.1% [90% confidence interval (CI) 44.5% to 65.3%] versus PCb 48.6% (90% CI 34.3% to 63.2%). Analysis for the stratified subgroups showed higher pCR rates with PO in the cohorts of patients <40 years and HR+ patients. CONCLUSION: GeparOLA could not exclude a pCR rate of ≤55% in the PO arm. PO was significantly better tolerated and the combination merits further evaluation.

[Risk-adapted surveillance: focus on familial breast and ovarian cancer]. / Risikoadaptierte Früherkennung : Schwerpunkt: Familiärer Brust- und Eierstockkrebs.

Breast cancer surveillance programs for the general population are not adequate for the small number of women with hereditary breast and ovarian cancer syndrome. Breast cancer screening for women in Germany starts at the age of 50 years, but nearly half of all women with familial risk are already diagnosed with breast cancer at that time. Moreover, mammography alone is not suitable for an early diagnosis of breast cancer in young women from high-risk families. Their typical dense breast tissue causes a high rate of false-negative cases. Therefore, national and international prospective clinical trials were initiated to offer a multimodal breast cancer surveillance program including magnetic resonance tomography for the breast and semi-annual screening intervals to women with BRCA1/2 mutations and those from high-risk families who tested negative for BRCA1/2 mutations. This program will currently be evaluated by the 15 centers of the German Consortium for Hereditary Breast and Ovarian Cancer.

Risk-reducing Surgery in Women at Risk for Familial Breast or Ovarian Cancer.

An estimated 5 % of breast cancers and 10 % of ovarian cancers may be due to inherited autosomal dominant breast and ovarian cancer alleles BRCA1 und BRCA2. According to population-based studies 1 or 2 women per 1000 carry such a risk allele. The cumulative cancer risk for healthy women with a BRCA-mutation is between 60 and 85 % for breast cancer and between 20 and 60 % for ovarian cancer. Recent studies have reported an increased risk for contralateral breast cancer in women after unilateral breast cancer. Since 1997 the German Cancer Aid has supported an interdisciplinary approach for high-risk women consisting of genetic testing, counselling and prevention in 12 specialised centres. Since 2005 this concept has received additional support from health insurance companies, and results have been assessed with regard to outcomes (e.g. reduced mortality due to more intensive early diagnosis). The number of centres has increased to 15 at various university hospitals. These interdisciplinary centres offer women the opportunity to participate in a structured screening programme for the early diagnosis of breast cancer and provide non-directive counselling on the options for risk-reducing surgery, e.g., prophylactic bilateral salpingo-oophorectomy, prophylactic bilateral mastectomy or contralateral prophylactic mastectomy after unilateral breast cancer. Such surgical interventions can significantly reduce the risk of disease, the respective disease-specific mortality and - particularly prophylactic bilateral salpingo-oophorectomy - total mortality in BRCA-mutation carriers.

Evaluation of variation in the phosphoinositide-3-kinase catalytic subunit alpha oncogene and breast cancer risk.

BACKGROUND: Somatic mutations in phosphoinositide-3-kinase catalytic subunit alpha (PIK3CA) are frequent in breast tumours and have been associated with oestrogen receptor (ER) expression, human epidermal growth factor receptor-2 overexpression, lymph node metastasis and poor survival. The goal of this study was to evaluate the association between inherited variation in this oncogene and risk of breast cancer. METHODS: A single-nucleotide polymorphism from the PIK3CA locus that was associated with breast cancer in a study of Caucasian breast cancer cases and controls from the Mayo Clinic (MCBCS) was genotyped in 5436 cases and 5280 controls from the Cancer Genetic Markers of Susceptibility (CGEMS) study and in 30 949 cases and 29 788 controls from the Breast Cancer Association Consortium (BCAC). RESULTS: Rs1607237 was significantly associated with a decreased risk of breast cancer in MCBCS, CGEMS and all studies of white Europeans combined (odds ratio (OR)=0.97, 95% confidence interval (CI) 0.95-0.99, P=4.6 × 10(-3)), but did not reach significance in the BCAC replication study alone (OR=0.98, 95% CI 0.96-1.01, P=0.139). CONCLUSION: Common germline variation in PIK3CA does not have a strong influence on the risk of breast cancer.

Association of hormone receptor status with grading, age of onset, and tumor size in BRCA1-associated breast cancer.

BRCA1-associated breast cancer frequently presents with estrogen-receptor (ERalpha) and progesterone-receptor (PR) negativity, grade 3, and early onset. In contrast, in BRCA1-deficient mice, ERalpha is highly expressed in early tumorigenesis. In a retrospective cohort study on 587 breast cancer patients with deleterious BRCA1 mutations, the correlation of ER, PR status, grading, age of onset, and tumor size was investigated. ERalpha and PR expression decreased from 62% in ductal carcinoma in situ (DCIS) to 20% and 16% in pT3, respectively (p value for ER 0.025 and PR 0.035, Fisher's exact test). The percentage of grade 1/2 tumors decreased from 44% in DCIS to 17% in pT3 (p value 0.074). Moreover, ER/PR positivity increased with increasing age. Our data suggest that early stage BRCA1-associated breast cancers are more frequently ERalpha and PR positive and low grade than advanced stages.

Platinum sensitivity in a BRCA1 mutation carrier with advanced breast cancer.

Although BRCA1-associated breast carcinomas are frequently detected in nodal-negative stage, they typically present with an aggressive histopathological phenotype that is reflected by a poor prognosis and an increased risk for distant metastatic spread. Recent in vitro data suggest a high sensitivity of BRCA1-associated carcinomas to platinum-based chemotherapy and a lower sensitivity to anthracyclines and taxanes. This is explained by the key role of BRCA1 in DNA double-strand repair via homologous recombination, thereby leading to a higher sensitivity to DNA intercalating agents, such as platinum. Here we present the case of a woman suffering from BRCA1-associated metastatic breast carcinoma that was resistant to docetaxel, but responded strongly to cisplatin-containing chemotherapy. This supports the rationale of ongoing clinical studies.

An evaluation of the polymorphisms Ins16bp and Arg72Pro in p53 as breast cancer risk modifiers in BRCA1 and BRCA2 mutation carriers.

The close functional relationship between p53 and the breast cancer susceptibility genes BRCA1 and BRCA2 has promoted the investigation of various polymorphisms in the p53 gene as possible risk modifiers in BRCA1/2 mutation carriers. Specifically, two polymorphisms in p53, c.97-147ins16bp and p.Arg72Pro have been analysed as putative breast cancer susceptibility variants, and it has been recently reported that a p53 haplotype combining the absence of the 16-bp insertion and the presence of proline at codon 72 (No Ins-72Pro) was associated with an earlier age at the onset of the first primary tumour in BRCA2 mutation carriers in the Spanish population. In this study, we have evaluated this association in a series of 2932 BRCA1/2 mutation carriers from the Consortium of Investigators of Modifiers of BRCA1 and BRCA2.

Strong evidence that the common variant S384F in BRCA2 has no pathogenic relevance in hereditary breast cancer.

INTRODUCTION: Unclassified variants (UVs) of unknown clinical significance are frequently detected in the BRCA2 gene. In this study, we have investigated the potential pathogenic relevance of the recurrent UV S384F (BRCA2, exon 10). METHODS: For co-segregation, four women from a large kindred (BN326) suffering from breast cancer were analysed. Moreover, paraffin-embedded tumours from two patients were analysed for loss of heterozygosity. Co-occurrence of the variant with a deleterious mutation was further determined in a large data set of 43,029 index cases. Nature and position of the UV and conservation among species were evaluated. RESULTS: We identified the unclassified variant S384F in three of the four breast cancer patients (the three were diagnosed at 41, 43 and 57 years of age). One woman with bilateral breast cancer (diagnosed at ages 32 and 50) did not carry the variant. Both tumours were heterozygous for the S384F variant, so loss of the wild-type allele could be excluded. Ser384 is not located in a region of functional importance and cross-species sequence comparison revealed incomplete conservation in the human, dog, rodent and chicken BRCA2 homologues. Overall, the variant was detected in 116 patients, five of which co-occurred with different deleterious mutations. The combined likelihood ratio of co-occurrence, co-segregation and loss of heterozygosity revealed a value of 1.4 x 10-8 in favour of neutrality of the variant. CONCLUSION: Our data provide conclusive evidence that the S384F variant is not a disease causing mutation.

[Molecular genetics and clinics of hereditary breast cancer]. / Molekulargenetik und Klinik des hereditären Mammakarzinoms.

Breast cancer is a heterogenous disease caused by mutations in tumor associated genes. While the vast majority of breast carcinomas occur sporadically, about 5% are attributable to dominant susceptibility alleles. Two major genes, BRCA1 and BRCA2, have been identified and account for a risk of up to 80% for breast cancer and up to 40% for ovarian cancer. Molecular genetic diagnosis allows the identification of women at risk that can be offered predictive meassures. Predictive strategies comprise primary, secondary and tertiary care. While data on medical prevention are still pending in this risk group, intensive surveillance and prophylactic surgery are proven to be effective in early tumor detection and reduction of incidence rates, respectively. However, there is little or no data regarding the efficacy of these procedures in terms of survival and quality of life. The German Hereditary Breast and Ovarian Cancer Consortium supported by the German Cancer Aid addresses these issues in a prospective cohort study with a standardized enrollment, prevention and follow up protocol. Results are presented in light of recent developments.

PTEN mutations do not cause nuclear beta-catenin accumulation in endometrial carcinomas.

PTEN: and beta-catenin mutations constitute the predominant genetic alterations in endometrioid carcinomas of the endometrium. PTEN encodes a dual-specificity phosphatase with lipid phosphatase and protein tyrosine phosphatase activities that regulate both apoptosis and interactions with the extracellular matrix. Recent studies have associated PTEN mutations with tumorigenesis of prostate carcinoma via the Wnt signaling pathway, leading to nuclear beta-catenin accumulation. To elucidate the potential interaction of PTEN and beta-catenin in endometrial cancer, we performed mutation analyses of the entire PTEN gene and of exon 3 of the beta-catenin gene that is most frequently targeted by mutations. A total of 82 endometrial carcinomas comprising 62 type I endometrioid carcinomas and 20 type II high-grade carcinomas were investigated. In addition in a subset of 22 carcinomas, the intracellular beta-catenin distribution was analyzed by immunohistochemistry. Overall, 20 (24.4%) of 82 tumors revealed mutations in the PTEN gene, and 16 (19.5%) of 82, in the beta-catenin gene. Six tumors (7.3%) showed mutations in both the PTEN and beta-catenin gene. Mutations were mainly detected in endometrioid carcinomas of the endometrium. As expected, a striking nuclear accumulation of beta-catenin could be shown in tumors with beta-catenin mutations. In the vast majority of tumors with PTEN mutations, a regular staining pattern of the cytoplasmic and membranous compartments was found. We therefore conclude that, in contrast to prostate cancer, mutations in the PTEN gene seem not to affect cellular distribution of the beta-catenin protein in endometrial carcinomas.

Familial ovarian dysgerminomas (Swyer syndrome) in females associated with 46 XY-karyotype.

An asymptomatic woman (age 38 years) with a family history of ovarian malignancies was referred for presymptomatic genetic testing of mutations in the BRCA genes. A familial Swyer syndrome with the occurrence of dysgerminomas is the most likely diagnosis. However, in our case, all known causes of this heterogeneous disorder have been excluded pointing to the existence of another yet unknown genetic locus. The family history revealed three affected paternal aunts. Two of them developed ovarian malignancies at 13 and 15 years of age, and died at ages 19 and 20. The third aunt, 82 years old, was affected by this disease at the age of 35. She underwent hormonal treatment for 3 years starting at the age of 15 because of primary amenorrhea. Under this treatment she developed nearly complete secondary sexual characteristics. Karyotype analysis revealed a normal male karyotype (46 XY, QFQ). Pelvic ultrasound showed an uterus of normal size, incompatible with an androgen resistance syndrome or a defect in testosterone biosynthesis. We excluded a mutation in the sex-determining region on chromosome Y (SRY) by direct sequencing of the SRY gene. An involvement of the subtelomeric region of chromosome 9p (9p 24.3) recently reported to be involved in XY-sex reversal phenotypes was excluded by molecular testing for loss of heterozygosity as well as fluorescence in situ hybridization studies. Analyses of the DAX1 gene in the dosage sensitive sex reversal locus on chromosome Xp21 by Southern blot analysis showed no duplications.

Breast MR imaging screening in 192 women proved or suspected to be carriers of a breast cancer susceptibility gene: preliminary results.

PURPOSE: To compare magnetic resonance (MR) imaging with conventional imaging in screening high-risk women. MATERIALS AND METHODS: This prospective trial included 192 asymptomatic and six symptomatic women who, on the basis of personal or family history or genetic analysis, were suspected or proved to carry a breast cancer susceptibility gene. RESULTS: Fifteen breast cancers were identified: nine in the 192 asymptomatic women (six in the first and three in the second screening round) and six in the symptomatic patients. Concerning the asymptomatic women, four of the nine breast cancers were detected and correctly classified with mammography and ultrasonography (US) combined; another two cancers were visible as well-circumscribed masses and were diagnosed as fibroadenomas. MR imaging allowed the correct classification and local staging of all nine cancers. In 105 asymptomatic women with validation of the 1st-year screening results, the sensitivities of mammography, US, and MR imaging were 33%, 33% (mammography and US combined, 44%), and 100%, respectively; the positive predictive values were 30%, 12%, and 64%, respectively. CONCLUSION: The accuracy of MR imaging is significantly higher than that of conventional imaging in screening high-risk women. Difficulties can be caused by an atypical manifestation of hereditary breast cancers at both conventional and MR imaging and by contrast material enhancement associated with hormonal stimulation.

Messenger RNA determination of estrogen receptor, progesterone receptor, pS2, and plasminogen activator inhibitor-1 by competitive reverse transcription-polymerase chain reaction in human breast cancer.

Estrogen receptor (ER), progesterone receptor (PR), the estrogen-inducible protein pS2, and plasminogen activator inhibitor-1 (PAI-1) are important prognostic factors in primary breast cancer. The protein concentrations of these factors in breast tumors have been well documented. However, few data about the mRNA expression of ER, PR, pS2, and PAI-1 in breast cancer are available, which is mostly due to the limitations of conventional techniques for mRNA analysis. We have described a competitive reverse transcription-PCR system for the simultaneous quantification of ER, PR, pS2, and PAI-1 mRNA in tumor samples. Here, we evaluated 100 tumor biopsies from breast cancer patients for the mRNA expression of ER, PR, pS2, and PAI-1. The results were analyzed for correlations with protein status and with clinical data. Significant correlations between mRNA expression levels and protein concentrations of all tested markers were found. In only a few cases was there an obvious discordance between the measurable amounts of mRNA and protein, especially for ER and PR. In addition, ER, PR, and pS2 mRNA levels correlated significantly with each other. No correlation between PAI-1 mRNA amount and the expression of the other markers was found. With respect to clinical data, ER and PR mRNA levels were found to be inversely correlated to tumor size and histological grade but not to the lymph node status. pS2 and PAI-1 mRNA expression were not correlated with tumor size, grade, or lymph node involvement. In conclusion, competitive reverse transcription-PCR may be used as an alternative for the study of prognostic factors in human breast cancer and other malignancies. However, before mRNA expression is measured for diagnostics, a presumed concordance of mRNA and protein expression must be evaluated very carefully for every gene.

Exclusion of a major role for the PTEN tumour-suppressor gene in breast carcinomas.

PTEN is a novel tumour-suppressor gene located on chromosomal band 10q23.3. This region displays frequent loss of heterozygosity (LOH) in a variety of human neoplasms including breast carcinomas. The detection of PTEN mutations in Cowden disease and in breast carcinoma cell lines suggests that PTEN may be involved in mammary carcinogenesis. We here report a mutational analysis of tumour specimens from 103 primary breast carcinomas and constitutive DNA from 25 breast cancer families. The entire coding region of PTEN was screened by single-strand conformation polymorphism (SSCP) analysis and direct sequencing using intron-based primers. No germline mutations could be identified in the breast cancer families and only one sporadic carcinoma carried a PTEN mutation at one allele. In addition, all sporadic tumours were analysed for homozygous deletions by differential polymerase chain reaction (PCR) and for allelic loss using the microsatellite markers D10S215, D10S564 and D10S573. No homozygous deletions were detected and only 10 out of 94 informative tumours showed allelic loss in the PTEN region. These results suggest that PTEN does not play a major role in breast cancer formation.

Expression of the ATM gene is significantly reduced in sporadic breast carcinomas.

The gene mutated in ataxia telangiectasia (A-T) patients (ATM) is located on chromosome 11q22-23, a region frequently altered in mammary tumors. Patients homozygous for ATM mutations are prone to develop a variety of different neoplasms. Female heterozygotes have been reported to carry a 5- to 8-fold increased risk of breast cancer. However, germline mutations in the ATM gene are rare in women with sporadic breast carcinomas. Most of the alterations described in A-T patients result in a functionally inactive ATM protein. Moreover, it has been suggested that mutations of the ATM gene in A-T patients influence the amount of ATM mRNA and that this may affect the severity of the disease. In the present study, we have analyzed ATM transcripts in a series of 39 breast carcinomas, 14 benign breast lesions and 12 normal breast tissue samples. ATM mRNA levels were determined by semiquantitative competitive RT-PCR. Competitor RNA molecules for the ATM gene and the housekeeping gene beta-2-microglobulin (B2M) were generated by PCR mutagenesis. Low concentrations of ATM transcripts were detected in breast carcinomas, intermediate levels in benign lesions and highest levels in normal breast tissue specimens (F-test, p = 0.0013). Our results indicate that reduced expression of the ATM gene may contribute to the development and/or malignant progression of breast carcinomas.

Genomic deletions in the BRCA1, BRCA2 and TP53 regions associate with low expression of the estrogen receptor in sporadic breast carcinoma.

Sporadic breast carcinoma is associated with multiple genetic alterations. The clinical relevance of these alterations, however, needs further clarification. In the present study we analyzed 266 spontaneously arising breast carcinomas for allelic losses in the BRCA1 and TP53 regions on chromosome 17, the BRCA2 region on chromosome 13, the ATM (mutated in ataxia-telangiectasia) region on chromosome 11 and on the chromosomal arms 7q and 16q. In addition the following clinical and pathological parameters were evaluated: age at diagnosis, tumor size, presence or absence of regional and distant metastases, hormone-receptor status, histopathological classification and tumor grading. The analysis of genetic and clinical observations revealed significant associations: absence of expression of the estrogen receptor was linked to a high rate of allelic losses of markers in the BRCA1, TP53 and BRCA2 regions. Expression of the progesterone receptor coincided with allelic loss on the long arm of chromosome 16. High-grade malignant lesions and ductal differentiation were frequently associated with allelic losses in the proximal portion of chromosome 17q. The accumulation of multiple allelic deletions was linked to high-grade malignant tumors, to tumor size, and to loss of expression of the estrogen receptor. Our data point to a relationship between clinically relevant prognostic factors and specific genomic deletions in the BRCA1, BRCA2 and TP53 region.

An optimized protocol for mRNA quantification using nested competitive RT-PCR.

Nested competitive reverse transcription polymerase chain reaction is an effective tool for the quantification of low level expressed mRNAs. Competitive RNA standards with small deletions allow the use cRT-PCR. The sensitivity is further increased by the utilization of nested PCR protocols. To optimize quantification of low abundance mRNAs we modified established protocols for use of automated labstations and semiautomated sequencers. In placental tissue, known for a very high CYP19 (P450AROM, aromatase) expression, cRT-PCR and nested cRT-PCR yielded virtually identical results which could be confirmed by Northern blotting. CYP19 mRNA in breast tumour tissue ranged below detection levels for Northern blotting; however, using our modified assay CYP19 showed 1.5 to 15 fold higher expression levels than in normal glandular breast tissue. Our approach proved to be useful for the quantification of a gene with low level expression. The employment of labstations and semiautomated sequencers allows rapid analysis of large sample numbers.