Location of Mutation in BRCA2 Gene and Survival in Patients with Ovarian Cancer

Purpose: BRCA2 plays a central role in homologous recombination by loading RAD51 on DNA breaks. The objective of this study is to determine whether the location of mutations in the RAD51-binding domain (RAD51-BD; exon 11) of BRCA2 gene affects the clinical outcome of ovarian cancer patients.Experimental Design: A study cohort of 353 women with ovarian cancer who underwent genetic germline testing for BRCA1 and BRCA2 genes was identified. Progression-free survival (PFS), platinum-free interval (PFI), and overall survival (OS) were analyzed. The Cancer Genome Atlas (TCGA) cohort of ovarian cancer (n = 316) was used as a validation cohort.Results: In the study cohort, 78 patients were carriers of germline mutations of BRCA2 After adjustment for FIGO stage and macroscopic residual disease, BRCA2 carriers with truncating mutations in the RAD51-BD have significantly prolonged 5-year PFS [58%; adjusted HR, 0.36; 95% confidence interval (CI), 0.20-0.64; P = 0.001] and prolonged PFI (29.7 vs. 15.5 months, P = 0.011), compared with noncarriers. BRCA2 carriers with mutations located in other domains of the gene do not have prolonged 5-year PFS (28%, adjusted HR, 0.67; 95% CI, 0.42-1.07; P = 0.094) or PFI (19 vs. 15.5 months, P = 0.146). In the TCGA cohort, only BRCA2 carriers harboring germline or somatic mutations in the RAD51-BD have prolonged 5-year PFS (46%; adjusted HR, 0.30; 95% CI, 0.13-0.68; P = 0.004) and 5-year OS (78%; adjusted HR, 0.09; 95% CI, 0.02-0.38; P = 0.001).Conclusions: Among ovarian cancer patients, BRCA2 carriers with mutations located in the RAD51-BD (exon 11) have prolonged PFS, PFI, and OS. Clin Cancer Res; 24(2); 326-33. ©2017 AACR.

[Doctor, I'm hot! Managing the effects of menopause in patients with breast cancer]

The incidence of breast cancer is rising up, but the mortality rate is decreasing, leading to a growing number of survivors. Most of these women are postmenopausal at diagnosis or will reach menopause following anti-cancer treatments. Most of them have hormone-sensitive tumors and will receive an anti-hormonal treatment. Endocrine therapy is associated with many adverse effects, including a worsening of climacteric symptoms with a negative impact on quality of life and therefore a suboptimal therapeutic adherence. Some supportive therapies can alleviate these adverse effects and should be offered to patients.

Breast cancer in younger women in Switzerland 1996-2009: a longitudinal population-based study

BACKGROUND

Breast cancer (BC) is the most commonly diagnosed cancer and a leading cause of death in younger women.

METHODS

We analysed incidence, mortality and relative survival (RS) in women with BC aged 20-49 years at diagnosis, between 1996 and 2009 in Switzerland. Trends are reported as estimated annual percentage changes (EAPC).

RESULTS

Our findings confirm a slight increase in the incidence of BC in younger Swiss women during the period 1996-2009. The increase was largest in women aged 20-39 years (EAPC 1.8%). Mortality decreased in both age groups with similar EAPCs. Survival was lowest among women 20-39 years (10-year RS 73.4%). We observed no notable differences in stage of disease at diagnosis that might explain these differences.

CONCLUSIONS

The increased incidence and lower survival in younger women diagnosed with BC in Switzerland indicates possible differences in risk factors, tumour biology and treatment characteristics that require additional examination.

Neoadjuvant treatment with docetaxel plus lapatinib, trastuzumab, or both followed by an anthracycline-based chemotherapy in HER2-positive breast cancer: results of the randomised phase II EORTC 10054 study

BACKGROUND

Neoadjuvant trials conducted using a double HER2 blockade with lapatinib and trastuzumab, combined with different paclitaxel-containing chemotherapy regimens, have shown high pathological complete response (pCR) rates, but at the cost of important toxicity. We hypothesised that this toxicity might be due to a specific interaction between paclitaxel and lapatinib. This trial assesses the toxicity and activity of the combination of docetaxel with lapatinib and trastuzumab.

PATIENTS AND METHODS

Patients with stage IIA to IIIC HER2-positive breast cancer received six cycles of chemotherapy (three cycles of docetaxel followed by three cycles of fluorouracil, epirubicin, cyclophosphamide). They were randomised 1 : 1 : 1 to receive during the first three cycles either lapatinib (1000 mg orally daily), trastuzumab (4 mg/kg loading dose followed by 2 mg/kg weekly), or trastuzumab + lapatinib at the same dose. The primary end point was pCR rate defined as ypT0/is. Secondary end points included safety and toxicity. pCR rate defined as ypT0/is ypN0 was assessed as an exploratory analysis. In June 2012, arm A was closed for futility based on the results from other studies.

RESULTS

From October 2010 to January 2013, 128 patients were included in 14 centres. The percentage of the 122 assessable patients with pCR in the breast, and pCR in the breast and nodes, was numerically highest in the lapatinib + trastuzumab group (60% and 56%, respectively), intermediate in the trastuzumab group (52% and 52%), and lowest in the lapatinib group (46% and 36%). Frequency (%) of the most common grade 3-4 toxicities in the lapatinib /trastuzumab/lapatinib + trastuzumab arms were: febrile neutropenia 23/15/10, diarrhoea 9/2/18, infection (other) 9/4/8, and hepatic toxicity 0/2/8.

CONCLUSIONS

This study demonstrates a numerically modest pCR rate increase with double anti-HER2 blockade plus chemotherapy, but suggests that the use of docetaxel rather than paclitaxel may not reduce toxicity.

CLINICALTRIALSGOV

NCT00450892.

Isolated tumor cells in sentinel lymph nodes of invasive breast cancer: cell displacement or metastasis?

The goal of this study was to determine whether the presence of isolated tumoral cells (ITCs) in sentinel lymph nodes (SLNs) after core needle biopsy (CNB) is related to the time interval between CNB and surgery and to histopathologic features of invasive breast cancer. Data from 633 consecutive patients with no micrometastasis or metastasis on both frozen sections and definitive pathologic examination of SLNs were retrieved from a prospective data base. No association was found between ITCs and the time interval between CNB and SLNB. The association was significant with tumor size, the tumor lymphovascular invasion (LVI) and the histologic type of the tumor. This study adds supplementary data to the association between tumoral LVI and ITCs in SLNs, The time interval between CNB procedure and SLNB was not related to affect presence of ITCs, which might not suggest the iatrogenic origin of these cells.

Pathological complete response after neoadjuvant chemotherapy is an independent predictive factor irrespective of simplified breast cancer intrinsic subtypes: a landmark and two-step approach analyses from the EORTC 10994/BIG 1-00 phase III trial

BACKGROUND

Pathological complete response (pCR) following chemotherapy is strongly associated with both breast cancer subtype and long-term survival. Within a phase III neoadjuvant chemotherapy trial, we sought to determine whether the prognostic implications of pCR, TP53 status and treatment arm (taxane versus non-taxane) differed between intrinsic subtypes.

PATIENTS AND METHODS

Patients were randomized to receive either six cycles of anthracycline-based chemotherapy or three cycles of docetaxel then three cycles of eprirubicin/docetaxel (T-ET). pCR was defined as no evidence of residual invasive cancer (or very few scattered tumour cells) in primary tumour and lymph nodes. We used a simplified intrinsic subtypes classification, as suggested by the 2011 St Gallen consensus. Interactions between pCR, TP53 status, treatment arm and intrinsic subtype on event-free survival (EFS), distant metastasis-free survival (DMFS) and overall survival (OS) were studied using a landmark and a two-step approach multivariate analyses.

RESULTS

Sufficient data for pCR analyses were available in 1212 (65%) of 1856 patients randomized. pCR occurred in 222 of 1212 (18%) patients: 37 of 496 (7.5%) luminal A, 22 of 147 (15%) luminal B/HER2 negative, 51 of 230 (22%) luminal B/HER2 positive, 43 of 118 (36%) HER2 positive/non-luminal, 69 of 221(31%) triple negative (TN). The prognostic effect of pCR on EFS did not differ between subtypes and was an independent predictor for better EFS [hazard ratio (HR) = 0.40, P < 0.001 in favour of pCR], DMFS (HR = 0.32, P < 0.001) and OS (HR = 0.32, P < 0.001). Chemotherapy arm was an independent predictor only for EFS (HR = 0.73, P = 0.004 in favour of T-ET). The interaction between TP53, intrinsic subtypes and survival outcomes only approached statistical significance for EFS (P = 0.1).

CONCLUSIONS

pCR is an independent predictor of favourable clinical outcomes in all molecular subtypes in a two-step multivariate analysis.

CLINICALTRIALSGOV

EORTC 10994/BIG 1-00 Trial registration number NCT00017095.

Abstract P6-04-05: Tamoxifen dose escalation based on endoxifen level: a prospective trial with genotyping, phenotyping and pharmacokinetics over 4 months

Background: Retrospective studies assessing the impact of tamoxifen (Tam) metabolism and its active metabolite, endoxifen, on the efficacy of the treatment produced conflicting results. The prospective CYPTAM-BRUT 2 trial is ongoing1. In the present study we assessed if the level of Tam metabolites could be improved by doubling tamoxifen dose in breast cancer patients (pts) with any CYP2D6 genotype, poor (PM), intermediate (IM) and also extensive metabolizer (EM).

Patients and methods: This multicenter, prospective, open-label trial included pts treated with Tam for ≥ 4 months. CYP2D6 activity was determined centrally by genotyping and phenotyping (dextromethorphan test). Liquid chromatography-tandem-mass spectrometry was used to measure Tam, N-desmethyltamoxifen (N-DMT), 4-hydroxytamoxifen (4-HT) and endoxifen twice at baseline (Tam 20 mg qd), then at days 30, 90 and 120 after having increased the dose to 20 mg bid. Endoxifen increase and the differences between genotype/phenotype subgroups were analyzed by ANOVA.

Results: 76 pts were analyzed. Steady-state concentrations for Tam and its metabolites were reached in 30 days after doubling the dose. A range of 1.6 to 1.8 fold increase was observed. Geometric mean plasma concentrations in ng/ml (CV%) were: at baseline and day 30 respectively 134 (48) and 246 (46) for tamoxifen (p &lt; 0.0001); 246 (53) and 413 (48) for N-DMT (p &lt; 0.0001); 2.3 (44) and 3.7 (51) for 4HT (p &lt; 0.0001); 18.7 (89) and 31.1 (92) for endoxifen (p = 0.005).

The level of endoxifen increased 1.4 to 1.7 folds in all genotype subgroups with geometric mean plasma concentrations in ng/ml (CV%): 6.9 (36) to 9.7 (24) in PMs (p = 0.7); 14.2 (69) to 20.7 (76) in IMs (p &lt; 0.0001); and 22.6 (76) to 38.7 (85) in EMs (p &lt; 0.0001). Similar results were obtained while considering phenotype subgroups. Genotypes and phenotypes explained less than 30% of the variability in endoxifen levels.

The occurrence of hot flashes and night sweating were followed prospectively. Endoxifen levels did not predict an increase in HF/NS events' overall occurrence (OR = 1.01, CI95% 0.78–1.31 for HF and 1.01, CI95% 0.79–1.29 for NS). Twelve pts received CYP2D6 inhibitors. Nine pts did not complete the planned 4 months with tamoxifen 20 mg bid. The main reasons were mood disorders, hot flashes, headache and nausea. Self-reported treatment compliance assessed by monthly anonymous questionnaire was ≥ 95%, except 80–95% in 4 pts.

Conclusions: This is the first trial reporting the impact of the increase of tamoxifen dose in all CYP2D6 genotypes, including EMs. Dose escalation of tamoxifen increased significantly the plasma level of endoxifen by similar ratio in all genotype subgroups.

Because of a huge inter-individual variability genotyping and phenotyping are not adequate surrogate markers of endoxifen level. Very low endoxifen levels are observed even in pts classified as EM.

Future trials aiming to improve the plasma level of endoxifen should consider direct measurement of the metabolite in plasma and adjust tamoxifen dose according to the initial level of the metabolite independently of the genotype.

Reference

1. A. Dieudonné, Journal of Clinical Oncology, 2011; vol 29, No 15, suppl (May 20, 2011): TPS 140

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-04-05.

[Breast cancer and obesity, a dangerous relation]

Obesity is associated with different cancers including breast cancer, whose incidence is increased in postmenopausal women. It has an adverse impact on the prognosis of the patients, regardless of their menopausal status. The fact of receiving a systemic adjuvant therapy does not neutralize the prognostic role of obesity. Moderate weight loss after cancer diagnosis could improve the outcome of the patients, while a weight gain during treatment seems without significant effect. Currently available data are still too incomplete to justify systematic programs to lose weight with an oncologic therapeutic aim. However, it is worth to encourage and support our patients to have an optimal diet, physical activity, and to lose weight as promotion of general health.

Prevention of palmoplantar erythrodysesthesia (PPE) with an antiperspirant in breast cancer patients treated with pegylated liposomal doxorubicin (PLD), a placebo-controlled, double blinded, phase lll trial (SAKK 92/08)

9059

Background: PPE, also known as hand-foot syndrome, is a distinctive adverse drug reaction of PLD treatment. PLD has been detected in elevated concentrations in eccrine sweat glands in palms and soles. We postulated that prophylactic administration of an antiperspirant (F511 cream) prior and during treatment with PLD could decrease the incidence of PPE. Methods: Patients (pts) with metastatic breast cancer treated with PLD monotherapy ≥10mg/m2 per week applied an antiperspirant to the left or right hand and foot and a corresponding placebo to the opposite site with double-blinding for the content of the cream applied to either side (intra-patient randomization). The creams were applied once daily during the first week, then three times per week. The primary endpoint was the rate of PPE grade (G) ≥ 2 in the antiperspirant or placebo treated side. Pts were evaluable if they developed PPE G ≥ 2 or had received cumulatively at least 160mg/m2 PLD. Patient-reported extent of symptom burden was a secondary endpoint. Using McNemar’s matched pairs design 53 pts were needed to detect a difference of 20% between the sides with a significance level of 5% and power of 90%. Results: 52 of 90 pts from 11 Swiss centers included were evaluable. Median age was 64.5 years; median duration of PLD treatment was 12 weeks. 30 pts developed PPE G ≥ 2. In 3 pts PPE G ≥ 2 occurred on the placebo side but not on the antiperspirant side (p=0.097; table). PPE G ≥ 2 was borderline significantly more frequent in placebo foot than antiperspirant foot (p=0.048). Patient-reported extent of symptom burden showed a trend in favor of the antiperspirant side for skin problems (peeling, blistering, bleeding) in the group of pts with PPE G ≥ 2 (p=0.051). Conclusions: In this double-blind trial with intra-patient randomization we observed a trend towards less PPE G ≥ 2 with application of the antiperspirant cream F511 in pts treated with PLD as determined by the treating physician and reported by the pts. [Table: see text]

[PARP inhibitors: new therapeutic agents in breast and ovarian cancer]

PARP inhibitors are novel drugs under development in oncology, particularly against breast and ovarian cancer. They act on the DNA repair mechanisms in synergy with the loss of BRCA function of the tumor cells, thereby inducing a genetic instability that leads to cell death. The clinical benefit of PARP inhibitors has been demonstrated for breast and ovarian cancer in BRCA germline mutation carriers. Their use in sporadic triple negative breast cancers, that share similarities with BRCA1 mutated tumors, is currently investigated with encouraging preliminary results.

Abstract PD05-09: Prospective Assessment of CYP2D6 by Genotyping, Phenotyping and Measurement of Tamoxifen, 4-Hydroxy-Tamoxifen and Endoxifen in Breast Cancer Patients Treated with Tamoxifen

Background: CYP2D6 is genetically highly polymorphic and several studies support that patients classified as poor-or intermediate-metabolizers achieve less or no benefit from tamoxifen treatment probably because they have lower levels of endoxifen. Genotyping is currently the major method used in studies and in clinical practice. However the ability of genotyping to predict plasma levels of endoxifen is uncertain for an individual patient. We assessed prospectively CYP2D6 activity by genotyping, phenotyping and the measurement of tamoxifen and its metabolites. Methods: Patients were genotyped for CYP2D6 (*1, *3, *4, *5, *6 and *XN) polymorphism. The CYP2D6 phenotype was determined by the dextromethorphan test. Plasma was collected at 2 time points after at least 4 months of treatment with tamoxifen 20 mg daily: tamoxifen, 4-hydroxytamoxifen, N-demethyltamoxifen and endoxifen were measured with high performance liquid chromatography coupled to triple stage tandem mass spectrometry. Linear regression analyses were performed on log transformed concentrations of tamoxifen, its metabolites, and the ratios 4- hydroxytamoxifen/tamoxifen, endoxifen/N-demethyltamoxifen versus the different genotype groups (UM, EM, IM, PM) and the dextromethorphan/dextrorphan ratio.

Results: The data of 26 patients are currently available. Geometric mean plasma concentrations (coefficient of variation %) of tamoxifen, N-desmethyltamoxifen, 4-OH-tamoxifen and endoxifen were 377 nmol/L (39%), 482 nmol/L (36%), 5.9 nmol/L (52%) and 60.7 nmol/L (94%), respectively. Genetic variation in CYP2D6 was significantly correlated with endoxifen, 4-hydroxytamoxifen and the ratios of 4-hydroxytamoxifen/tamoxifen and endoxifen/N-demethyltamoxifen: determination coefficients (R-squared) of 44% (P=0.0002), 30% (P=0.0038), 57% (P= &lt;0.0001) and 47% (P=0.0001), respectively. Phenotypes defined by the dextromethorphan/dextrorphan ratio were significantly correlated with endoxifen and the ratios of 4-hydroxytamoxifen/tamoxifen and endoxifen/N-demethyltamoxifen: determination coefficients of 47% (P=0.0002), 39% (P=0.0012) and 59% (P= &lt;0.0001), respectively. Conclusions: Our data confirm a significant correlation between CYP2D6 activity defined by genotyping or by phenotyping and plasma levels of endoxifen. However, the important interindividual variability in the concentrations of the metabolites of tamoxifen remains largely unexplained, suggesting that CYP2D6 genotyping and phenotyping are not sufficient to predict plasma levels of the active metabolites of tamoxifen. These preliminary results are consistent with a potential superiority of monitoring the active metabolites themselves rather than genetic or phenotypic surrogates. The study is ongoing and more data will be presented.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr PD05-09.

[Impact of breast MRI and PET-CT in breast cancer staging]

The preoperative staging of breast carcinoma determines the type of surgery. Mammography and echography are considered standard. Even though, breast MRI shows better performance for evaluation of the size of the tumor and for detection of additional foci of the tumor. Breast MRI appears to lead to more extensive surgery or increased numbers of mastectomy. But it remains unclear whether breast MRI contributes to reduce positive surgical margins, local recurrences and whether it increases survival. Because of the low predictive positive value, every MRI finding should be confirmed by core needle biopsy. PET-CT has the best sensibility for the detection of distant metastasis but should only be used in very high risk patients.