Clinico-pathologic relationships with Ki67 and its change with short-term aromatase inhibitor treatment in primary ER + breast cancer: further results from the POETIC trial (CRUK/07/015).

PURPOSE: Ki67 assessed at diagnosis (Ki67baseline) is an important prognostic factor in primary oestrogen receptor-positive (ER +) breast cancer. Proportional change in Ki67 after 2 weeks (∆Ki672week) is associated with clinical benefit from endocrine therapies and residual Ki67 (Ki672week) with recurrence-free survival. The aim was to define the association between Ki67baseline and after aromatase inhibitor (AI) exposure ∆Ki672week and Ki672week with key prognostic and biologic factors utilising data from the POETIC study. PATIENTS AND METHODS: In POETIC 4480 postmenopausal patients with primary ER and/or PgR + breast cancer were randomised 2:1 to 2 weeks' presurgical AI (anastrozole or letrozole) or no presurgical treatment (control). Ki67 was measured centrally in core-cut biopsies taken prior to AI and in core-cuts or the excision biopsy at surgery. Relationships between the Ki67 and biologic factors were explored using linear regression. RESULTS: Established associations of Ki67baseline with biologic factors including PgR status, tumour grade, tumour size, histological subtype, nodal status, and vascular invasion were confirmed in the HER2- subpopulation. In the HER2 + subpopulation only grade and tumour size were significantly associated with Ki67baseline. In control group Ki672week was 18% lower than Ki67baseline (p < 0.001) when Ki672week was measured in excision biopsies but not when measured in core-cuts. Median suppression by AIs (∆Ki672week) was 79.3% (IQR: -89.9 to -54.6) and 53.7% (IQR: -78.9 to -21.1) for HER2-negative and HER2-positive cases, respectively. Significantly less suppression occurred in PgR- vs PgR + and HER2 + vs HER2- tumours which remained apparent after adjustment for 2-week sample type. CONCLUSIONS: The magnitude of this study allowed characterisation of relationships between Ki67baseline, ∆Ki672week and Ki672week with high degrees of confidence providing a reference source for other studies. Lower values of Ki67 occur when measured on excision biopsies and could lead to apparent but artefactual decreases in Ki67: this should be considered when either ∆Ki672week or Ki672week is used in routine clinical practice to aid treatment decisions or in clinical trials assessing new drug therapies.

Evidence into practice: a national cohort study of NICE-recommended oncological drug therapy utilisation among women diagnosed with invasive breast cancer in England.

BACKGROUND: Multiple drug treatments are approved for invasive breast cancer (IBC). We investigated uptake of NICE-recommended oncological drugs and variation by age, comorbidity burden and geographical region. METHODS: Women (aged 50+ years) diagnosed with IBC from 2014 to 2019, were identified from England Cancer Registry data and drug utilisation from Systemic Anti-Cancer Therapy data. Interrupted time series analysis assessed national-level changes in drug use after publication of NICE recommendations. Regression models analysed variation in use. RESULTS: This national cohort included 168,449 women. Use of drugs recommended for first-line treatment varied, from 26.6% for CDK 4/6 inhibitors to 63.8% for HER2-targeting therapies. Utilisation of drugs with a NICE recommendation published between 2014 and 2019, increased among patients diagnosed around the time of publication, except in the case of pertuzumab for metastatic breast cancer (MBC) which was previously accessible via the Cancer Drugs Fund (though use of pertuzumab for MBC increased from 34.1% to 75.0% across the study period). Use of trastuzumab and neoadjuvant/adjuvant pertuzumab varied by geographical region. Use was low for ribociclib (2.2%), abemaciclib (2.3%) and for drugs recommended beyond the first-line setting. For all drugs, use after NICE recommendation varied by age at diagnosis and increased as stage increased. CONCLUSIONS: Use of NICE-recommended drugs for IBC in routine care is variable, with lowest use among women aged 70+ years. Improving access to effective treatments is an important step in improving outcomes.

Bridging pre-surgical endocrine therapy for breast cancer during the COVID-19 pandemic: outcomes from the B-MaP-C study.

PURPOSE: The B-MaP-C study investigated changes to breast cancer care that were necessitated by the COVID-19 pandemic. Here we present a follow-up analysis of those patients commenced on bridging endocrine therapy (BrET), whilst they were awaiting surgery due to reprioritisation of resources. METHODS: This multicentre, multinational cohort study recruited 6045 patients from the UK, Spain and Portugal during the peak pandemic period (Feb-July 2020). Patients on BrET were followed up to investigate the duration of, and response to, BrET. This included changes in tumour size to reflect downstaging potential, and changes in cellular proliferation (Ki67), as a marker of prognosis. RESULTS: 1094 patients were prescribed BrET, over a median period of 53 days (IQR 32-81 days). The majority of patients (95.6%) had strong ER expression (Allred score 7-8/8). Very few patients required expedited surgery, due to lack of response (1.2%) or due to lack of tolerance/compliance (0.8%). There were small reductions in median tumour size after 3 months' treatment duration; median of 4 mm [IQR - 20, 4]. In a small subset of patients (n = 47), a drop in cellular proliferation (Ki67) occurred in 26 patients (55%), from high (Ki67 ≥ 10%) to low (< 10%), with at least one month's duration of BrET. DISCUSSION: This study describes real-world usage of pre-operative endocrine therapy as necessitated by the pandemic. BrET was found to be tolerable and safe. The data support short-term (≤ 3 months) usage of pre-operative endocrine therapy. Longer-term use should be investigated in future trials.

The COVID-19 pandemic and impact on breast cancer diagnoses: what happened in England in the first half of 2020.

Delays in cancer diagnosis and treatment due to the COVID-19 pandemic is a widespread source of concern, but the scale of the challenge for different tumour sites is not known. Routinely collected NHS England Cancer Waiting Time data were analysed to compare activity for breast cancer in the first 6 months of 2020 compared to the same time period in 2019. The number of referrals for suspected breast cancer was 28% lower (N = 231,765 versus N = 322,994), and the number of patients who received their first treatment for a breast cancer diagnosis was 16% lower (N = 19,965 versus N = 23,881). These data suggest that the number of breast cancers diagnosed during the first half of 2020 is not as low as initially feared, and a substantial proportion of the shortfall can be explained by the suspension of routine screening in March 2020. Further work is needed to examine in detail the impact of measures to manage the COVID-19 pandemic on breast cancer outcomes.

Breast cancer management pathways during the COVID-19 pandemic: outcomes from the UK 'Alert Level 4' phase of the B-MaP-C study.

BACKGROUND: The B-MaP-C study aimed to determine alterations to breast cancer (BC) management during the peak transmission period of the UK COVID-19 pandemic and the potential impact of these treatment decisions. METHODS: This was a national cohort study of patients with early BC undergoing multidisciplinary team (MDT)-guided treatment recommendations during the pandemic, designated 'standard' or 'COVID-altered', in the preoperative, operative and post-operative setting. FINDINGS: Of 3776 patients (from 64 UK units) in the study, 2246 (59%) had 'COVID-altered' management. 'Bridging' endocrine therapy was used (n = 951) where theatre capacity was reduced. There was increasing access to COVID-19 low-risk theatres during the study period (59%). In line with national guidance, immediate breast reconstruction was avoided (n = 299). Where adjuvant chemotherapy was omitted (n = 81), the median benefit was only 3% (IQR 2-9%) using 'NHS Predict'. There was the rapid adoption of new evidence-based hypofractionated radiotherapy (n = 781, from 46 units). Only 14 patients (1%) tested positive for SARS-CoV-2 during their treatment journey. CONCLUSIONS: The majority of 'COVID-altered' management decisions were largely in line with pre-COVID evidence-based guidelines, implying that breast cancer survival outcomes are unlikely to be negatively impacted by the pandemic. However, in this study, the potential impact of delays to BC presentation or diagnosis remains unknown.

Bridging The Age Gap: observational cohort study of effects of chemotherapy and trastuzumab on recurrence, survival and quality of life in older women with early breast cancer.

BACKGROUND: Chemotherapy improves outcomes for high risk early breast cancer (EBC) patients but is infrequently offered to older individuals. This study determined if there are fit older patients with high-risk disease who may benefit from chemotherapy. METHODS: A multicentre, prospective, observational study was performed to determine chemotherapy (±trastuzumab) usage and survival and quality-of-life outcomes in EBC patients aged ≥70 years. Propensity score-matching adjusted for variation in baseline age, fitness and tumour stage. RESULTS: Three thousands four hundred sixteen women were recruited from 56 UK centres between 2013 and 2018. Two thousands eight hundred eleven (82%) had surgery. 1520/2811 (54%) had high-risk EBC and 2059/2811 (73%) were fit. Chemotherapy was given to 306/1100 (27.8%) fit patients with high-risk EBC. Unmatched comparison of chemotherapy versus no chemotherapy demonstrated reduced metastatic recurrence risk in high-risk patients(hazard ratio [HR] 0.36 [95% CI 0.19-0.68]) and in 541 age, stage and fitness-matched patients(adjusted HR 0.43 [95% CI 0.20-0.92]) but no benefit to overall survival (OS) or breast cancer-specific survival (BCSS) in either group. Chemotherapy improved survival in women with oestrogen receptor (ER)-negative cancer (OS: HR 0.20 [95% CI 0.08-0.49];BCSS: HR 0.12 [95% CI 0.03-0.44]).Transient negative quality-of-life impacts were observed. CONCLUSIONS: Chemotherapy was associated with reduced risk of metastatic recurrence, but survival benefits were only seen in patients with ER-negative cancer. Quality-of-life impacts were significant but transient. TRIAL REGISTRATION: ISRCTN 46099296.

Long-term outcome and prognostic value of Ki67 after perioperative endocrine therapy in postmenopausal women with hormone-sensitive early breast cancer (POETIC): an open-label, multicentre, parallel-group, randomised, phase 3 trial.

BACKGROUND: Preoperative and perioperative aromatase inhibitor (POAI) therapy has the potential to improve outcomes in women with operable oestrogen receptor-positive primary breast cancer. It has also been suggested that tumour Ki67 values after 2 weeks (Ki672W) of POAI predicts individual patient outcome better than baseline Ki67 (Ki67B). The POETIC trial aimed to test these two hypotheses. METHODS: POETIC was an open-label, multicentre, parallel-group, randomised, phase 3 trial (done in 130 UK hospitals) in which postmenopausal women aged at least 50 years with WHO performance status 0-1 and hormone receptor-positive, operable breast cancer were randomly assigned (2:1) to POAI (letrozole 2·5 mg per day orally or anastrozole 1 mg per day orally) for 14 days before and following surgery or no POAI (control). Adjuvant treatment was given as per UK standard local practice. Randomisation was done centrally by computer-generated permuted block method (variable block size of six or nine) and was stratified by hospital. Treatment allocation was not masked. The primary endpoint was time to recurrence. A key second objective explored association between Ki67 (dichotomised at 10%) and disease outcomes. The primary analysis for clinical endpoints was by modified intention to treat (excluding patients who withdrew consent). For Ki67 biomarker association and endpoint analysis, the evaluable population included all randomly assigned patients who had paired Ki67 values available. This study is registered with ClinicalTrials.gov, NCT02338310; the European Clinical Trials database, EudraCT2007-003877-21; and the ISRCTN registry, ISRCTN63882543. Recruitment is complete and long-term follow-up is ongoing. FINDINGS: Between Oct 13, 2008, and April 16, 2014, 4480 women were recruited and randomly assigned to POAI (n=2976) or control (n=1504). On Feb 6, 2018, median follow-up was 62·9 months (IQR 58·1-74·1). 434 (10%) of 4480 women had a breast cancer recurrence (280 [9%] POAI; 154 [10%] control), hazard ratio 0·92 (95% CI 0·75-1·12); p=0·40 with the proportion free from breast cancer recurrence at 5 years of 91·0% (95% CI 89·9-92·0) for patients in the POAI group and 90·4% (88·7-91·9) in the control group. Within the POAI-treated HER2-negative subpopulation, 5-year recurrence risk in women with low Ki67B and Ki672W (low-low) was 4·3% (95% CI 2·9-6·3), 8·4% (6·8-10·5) with high Ki67B and low Ki672W (high-low) and 21·5% (17·1-27·0) with high Ki67B and Ki672W (high-high). Within the POAI-treated HER2-positive subpopulation, 5-year recurrence risk in the low-low group was 10·1% (95% CI 3·2-31·3), 7·7% (3·4-17·5) in the high-low group, and 15·7% (10·1-24·4) in the high-high group. The most commonly reported grade 3 adverse events were hot flushes (20 [1%] of 2801 patients in the POAI group vs six [<1%] of 1400 in the control group) and musculoskeletal pain (29 [1%] vs 13 [1%]). No treatment-related deaths were reported. INTERPRETATION: POAI has not been shown to improve treatment outcome, but can be used without detriment to help select appropriate adjuvant therapy based on tumour Ki67. Most patients with low Ki67B or low POAI-induced Ki672W do well with adjuvant standard endocrine therapy (giving consideration to clinical-pathological factors), whereas those whose POAI-induced Ki672W remains high might benefit from further adjuvant treatment or trials of new therapies. FUNDING: Cancer Research UK.

Levels of different subtypes of tumour-infiltrating lymphocytes correlate with each other, with matched circulating lymphocytes, and with survival in breast cancer.

PURPOSE: Breast cancer tumour-infiltrating lymphocytes associate with clinico-pathological factors, including survival, although the literature includes many conflicting findings. Our aim was to assess these associations for key lymphocyte subtypes and in different tumour compartments, to determine whether these provide differential correlations and could, therefore, explain published inconsistencies. Uniquely, we also examine whether infiltrating levels merely reflect systemic lymphocyte levels or whether local factors are predominant in recruitment. METHODS: Immunohistochemistry was used to detect tumour-infiltrating CD20+ (B), CD4+ (helper T), CD8+ (cytotoxic T) and FoxP3+ (regulatory T) cells in breast cancers from 62 patients, with quantification in tumour stroma, tumour cell nests, and tumour margins. Levels were analysed with respect to clinico-pathological characteristics and matched circulating levels (determined by flow-cytometry). RESULTS: CD4+ lymphocytes were the most prevalent subtype in tumour stroma and at tumour edge and CD8+ lymphocytes were most prevalent in tumour nests; FoxP3+ lymphocytes were rarest in all compartments. High grade or hormone receptor negative tumours generally had significantly increased lymphocytes, especially in tumour stroma. Only intra-tumoural levels of CD8+ lymphocytes correlated significantly with matched circulating levels (p < 0.03), suggesting that recruitment is mainly unrelated to systemic activity. High levels of stromal CD4+ and CD20+ cells associated with improved survival in hormone receptor negative cases (p < 0.04), while tumour nest CD8+ and FoxP3+ cells associated with poor survival in hormone receptor positives (p < 0.005). CONCLUSIONS: Lymphocyte subtype and location define differential impacts on tumour biology, therefore, roles of tumour-infiltrating lymphocytes will only be unravelled through thorough analyses that take this into account.

Costs of Early Invasive Breast Cancer in England Using National Patient-Level Data.

OBJECTIVES: This study aimed to use patient-level data to provide up-to-date estimates of early invasive breast cancer care costs by stage in England and to explore to what extent these costs varied based on patients' ages and geographic regions. METHODS: This study identified women aged 50 years and older who had been diagnosed with early invasive breast cancer between January 1, 2014, and December 31, 2015, using linked cancer registrations and routine hospital data sets generated from the usual care for all National Health Service trusts in England. Cost estimates were derived from hospital records in Hospital Episodes Statistics with additional chemotherapy and radiotherapy information from the national data sets. We fitted general linear regression models to analyze the cost data. The model that best fit the data was selected using the model selection criteria of Akaike information criterion. RESULTS: 55 662 women with early invasive breast cancer in England were included. The generalized linear model with log-gamma distribution fit the data best. The costs of breast cancer care for 1 year after diagnosis were strongly dependent on stage at diagnosis, controlling for other covariates. The estimated average per-patient hospital-related costs were £5167 at stage I, £7613 at stage II, and £13 330 at stage IIIA. Costs decreased with increasing age (P < .001) and varied across region (P < .001), deprivation level (P < .001), referral source (P < .01), presence of comorbidities (P< .001), and tumor receptor (ER/PR/HER2) status (P < .001). CONCLUSIONS: In England, the costs of breast cancer care increased with advancing stage of the disease at diagnosis. Breast cancer costs varied by age and geographic region.

Human Epidermal Growth Factor 2-positive Breast Cancer with Mammographic Microcalcification: Relationship to Pathologic Complete Response after Neoadjuvant Chemotherapy.

Purpose To determine the relationship between the presence or absence of mammographic calcifications in human epidermal growth factor receptor 2 (HER2)-positive breast cancers and pathologic complete response (pCR) to neoadjuvant chemotherapy and to determine other tumor and clinical characteristics that may be predictive of such a response. Materials and Methods A database of all patients with HER2-positive breast cancer who underwent neoadjuvant chemotherapy between 2007 and 2015 was retrospectively reviewed. Patient demographic characteristics, mammographic appearance, molecular subtype of cancer (luminal or nonluminal), radiologic response (based on breast magnetic resonance images), surgery, and pathologic response to treatment were recorded. Inter- and subgroup comparison was performed for presence of mammographic microcalcification and cancer subtype by using Mann-Whitney and χ2 tests and logistic regression. Results A total of 111 patients with a median age of 49 years (interquartile range, 40-57 years) were evaluated. Of these, 64.9% (72 of 111) had mammographic microcalcifications, 63.1% (70 of 111) had luminal B cancer, and 36.9% (41 of 111) had nonluminal HER2-positive cancer. Radiologic response to neoadjuvant chemotherapy was observed in 70.3% (78 of 111) of patients. Surgery was performed in 97.3% (108 of 111) of patients, and 30.6% (34 of 111) of patients underwent breast conservation. pCR was observed in 33.3% (37 of 111) of patients; 16.2% (18 of 111) showed residual ductal carcinoma in situ and 50.5% (56 of 111) had residual invasive disease. The pCR rate was the same (P = .21) in patients with mammographic microcalcification (29.2% [21 of 72]) as in those without calcification (41.0% [16 of 39]). The pCR rate in patients with nonluminal HER2-positive cancers (46.3% [19 of 41]) was higher (P = .01) than in those with luminal B cancers (25.7% [18 of 70]). pCR was associated with nonluminal HER2-positive subtype (odds ratio, 5.4; 95% confidence interval: 1.8, 16.0; P = .01) and complete radiologic response (odds ratio, 20.4; 95% confidence interval: 3.3, 126.6; P = .01). Conclusion Patients with HER2-positive cancer and mammographic microcalcification can achieve pCR after neoadjuvant chemotherapy. Nonluminal HER2-positive subtype and complete radiologic response are predictors of pCR.

Lymphocyte depletion and repopulation after chemotherapy for primary breast cancer.

BACKGROUND: Approximately 30 % of breast cancer patients receive chemotherapy, yet little is known about influences of current regimens on circulating lymphocyte levels and phenotypes. Similarly, clinico-pathological factors that modify these influences, and implications for future immune health remain mainly unexplored. METHODS: We used flow-cytometry to assess circulating lymphocyte levels and phenotypes in 88 primary breast cancer patients before chemotherapy and at time-points from 2 weeks to 9 months after chemotherapy completion. We examined circulating titres of antibodies against pneumococcal and tetanus antigens using ELISAs. RESULTS: Levels of B, T and NK cells were significantly reduced 2 weeks after chemotherapy (p < 0.001). B cells demonstrated particularly dramatic depletion, falling to 5.4 % of pre-chemotherapy levels. Levels of all cells recovered to some extent, although B and CD4(+) T cells remained significantly depleted even 9 months post-chemotherapy (p < 0.001). Phenotypes of repopulating B and CD4(+) T cells were significantly different from, and showed no sign of returning to pre-chemotherapy profiles. Repopulating B cells were highly depleted in memory cells, with proportions of memory cells falling from 38 % to 10 % (p < 0.001). Conversely, repopulating CD4(+) T cells were enriched in memory cells, which increased from 63 % to 75 % (p < 0.001). Differences in chemotherapy regimen and patient smoking were associated with significant differences in depletion extent or repopulation dynamics. Titres of anti-pneumococcal and anti-tetanus antibodies were both significantly reduced post-chemotherapy and did not recover during the study (p < 0.001). CONCLUSION: Breast cancer chemotherapy is associated with long-term changes in immune parameters that should be considered during clinical management.

Short-term breast cancer survival in relation to ethnicity, stage, grade and receptor status: national cohort study in England.

BACKGROUND: In the re-organisation of cancer registration in England in 2012, a high priority was given to the recording of cancer stage and other prognostic clinical data items. METHODS: We extracted 86 852 breast cancer records for women resident in England and diagnosed during 2012-2013. Information on age, ethnicity, socio-economic status, comorbidity, tumour stage, grade, morphology and oestrogen, progesterone and HER2 receptor status was included. The two-year cumulative risk of death from any cause was estimated with the Kaplan-Meier method, and univariate and multivariate Cox proportional hazards regressions were used to estimate hazard ratios (HR) and their 95% confidence intervals (95% CI). The follow-up ended on 31 December 2014. RESULTS: The completeness of registration for prognostic variables was generally high (around 80% or higher), but it was low for progesterone receptor status (41%). Women with negative receptor status for each of the oestrogen, progesterone and HER2 receptors (triple-negative cancers) had an adjusted HR for death of 2.00 (95%CI 1.84-2.17). Black women had an age-adjusted HR of 1.77 (1.48-2.13) compared with White women. CONCLUSIONS: The excess mortality of Black women with breast cancer has contributions from socio-economic factors, stage distribution and tumour biology. The study illustrates the richness of detail in the national cancer registration data. This allows for analysis of cancer outcomes at a high level of resolution, and may form the basis for risk stratification.

Chemotherapy induces Notch1-dependent MRP1 up-regulation, inhibition of which sensitizes breast cancer cells to chemotherapy.

BACKGROUND: Multi-drug Resistance associated Protein-1 (MRP1) can export chemotherapeutics from cancer cells and is implicated in chemoresistance, particularly as is it known to be up-regulated by chemotherapeutics. Our aims in this study were to determine whether activation of Notch signalling is responsible for chemotherapy-induced MRP1 expression Notch in breast cancers, and whether this pathway can be manipulated with an inhibitor of Notch activity. METHODS: MRP1 and Notch1 were investigated in 29 patients treated with neoadjuvant chemotherapy (NAC) for breast cancer, using immunohistochemistry on matched biopsy (pre-NAC) and surgical samples (post-NAC). Breast epithelial cell cultures (T47D, HB2) were treated with doxorubicin in the presence and absence of functional Notch1, and qPCR, siRNA, Western blots, ELISAs and flow-cytometry were used to establish interactions. RESULTS: In clinical samples, Notch1 was activated by neoadjuvant chemotherapy (Wilcoxon signed-rank p < 0.0001) and this correlated with induction of MRP1 expression (rho = 0.6 p = 0.0008). In breast cell lines, doxorubicin induced MRP1 expression and function (non-linear regression p < 0.004). In the breast cancer line T47D, doxorubicin activated Notch1 and, critically, inhibition of Notch1 activation with the γ-secretase inhibitor DAPT abolished the doxorubicin-induced increase in MRP1 expression and function (t-test p < 0.05), resulting in enhanced cellular retention of doxorubicin and increased doxorubicin-induced apoptosis (t-test p = 0.0002). In HB2 cells, an immortal but non-cancer derived breast cell line, Notch1-independent MRP1 induction was noted and DAPT did not enhance doxorubicin-induced apoptosis. CONCLUSIONS: Notch inhibitors may have potential in sensitizing breast cancer cells to chemotherapeutics and therefore in tackling chemoresistance.

Adding value to rare tissue samples donated to biobanks: characterisation of breast tissue and primary cell cultures obtained from a female-to-male transgender patient.

Biobanks provide a window of opportunity to store and add value to material from rare cases allowing their future use in biomedical research. One such example is the opportunityto obtain good quality tissue from patients undergoing gender re-assignment. Following patient agreement to donate tissue samples to our biobank we catalogued the histological appearance, defined the expression of the hormone receptors ERα, PR, AR and the proliferation marker Ki67, and generated and characterised primary cell cultures in a female to male (FTM) transgender patient referred to our unit for surgery. Immunohistochemistry was performed for ERα, PR and AR and the proliferation marker Ki67. Hormone receptor expression was confined to epithelial cells lining the breast ducts. Ki67 immunoreactivity was sparse indicating little proliferation of luminal epithelium, consistent with normal mammary gland. Cultures of epithelial cells and fibroblasts were derived from surplus tissue. The latter lacked expression of epithelial markers and hormone receptors but exhibited expression of vimentin. Culture of the former on Matrigel saw an outgrowth of more rounded "epithelial-like" cells. Immunofluoresence characterisation showed a mixed phenotype with expression of vimentin and both myoepithelial and luminal epithelial markers. Sporadic weak ERα expression and moderate PR expression was seen. In summary, as well as routinely collecting tissue and blood samples, we have characterised and stored tissue and cells from a FTM transgender patient, adding value to this resource which,available from the Breast Cancer Campaign Tissue Bank for those interested in further studying the biology of FTM transgender tissue.

PSMD9 expression predicts radiotherapy response in breast cancer.

BACKGROUND: More than 50% of cancer patients are recommended to receive radiotherapy. Recommendations are based mainly on clinical and pathological factors and not intrinsic tumour radio-sensitivity. Use of radiotherapy according to predictive markers would potentially reduce costly over-treatment, and improve the treatment risk-benefit ratio and cancer outcomes. Tumour expression of the 26S proteasome has been reported to predict radiotherapy response: low expression was associated with higher rates of local recurrence after radiotherapy, suggesting that low proteasome expression and activity was associated with radio-resistance. However, this conclusion is at odds with the emerging use of proteasome inhibitors as radio-sensitizers. Our aim was to further analyse the relevance of 26S proteasome expression, focussing specifically on the PSMD9 subunit, in the largest clinical cohort to date, and to investigate the functional role of PSMD9 in radio-sensitivity in breast cancer cell lines. METHODS: We examined expression of PSMD9 using immunohistochemistry in a cohort of 157 breast cancer patients, including 32 cases (20.4%) that subsequently developed local recurrences. The value of expression as a prognostic or radiotherapy predictive marker was tested using Kaplan-Meier and Cox regression analyses. PSMD9 function was examined in breast cancer cell lines MCF7 and MDA-MB-231 using siRNA knock-downs and colony forming assays after irradiation. RESULTS: Low tumour PSMD9 expression was significantly associated with a reduced incidence of local recurrence in patients receiving adjuvant radiotherapy (univariate log rank p = 0.02; multivariate regression p = 0.009), but not in those treated without radiotherapy, suggesting that low PSMD9 expression was associated with relative tumour radio-sensitivity. In support of this, reduction of PSMD9 expression using siRNA in breast cancer cell lines in vitro sensitized cells to radiotherapy. CONCLUSIONS: We conclude that PSMD9 expression may predict radiotherapy benefit, with low expression indicative of relative radio-sensitivity, the opposite of previous reports relating to 26S proteasome expression. Our conclusion is compatible with use of proteasome inhibitors as radio-sensitizers, and highlights PSMD9 as a potential target for radio-sensitizing drugs.

The potential utility of geminin as a predictive biomarker in breast cancer.

Compared with other markers of cell proliferation, geminin is unique being expressed selectively during the proliferative phase of the cell cycle, specifically S, G2 and early mitosis, disappearing completely at the metaphase-anaphase transition. We aimed to compare the prognostic significance of geminin to that of Ki67, a proliferation marker which has been investigated in many breast cancer studies. Breast cancer tissue microarrays containing 368 tumours were stained using anti-geminin and Ki67 antibodies. Labelling index (LI) was calculated for geminin, and the percentage of positive cancer nuclei was determined for Ki67. A receiver operation characteristics analysis was used to determine the optimum cut-off value for geminin (LI ≥ 2), and for Ki67, a score of ≥14 % was considered as positive for survival analysis. Geminin expression correlated positively with Ki67 expression (r = 0.686, p = 0.001). Survival analysis showed only geminin, and not Ki67-positive patients to have poor (breast cancer-specific survival) BCSS [HR 2.85 (1.53-5.32)] and (disease-free survival) DFS [HR 2.63 (1.47-4.71)]. On univariate analysis, along with known clinicopathological variables, both Ki67 and geminin LI were found to be significant predictors of BCSS and DFS. On multivariate analysis, only tumour size, nodal status and adjuvant hormonal therapy were found to be independent predictors for both BCSS and DFS, while geminin positivity (LI ≥ 2 %) was found to be an independent predictor for BCSS [HR 2.27 (1.01-5.06); p = 0.04]. In comparison with Ki67, a more established proliferation marker, geminin expression was a better predictor of adverse outcome in this cohort of breast cancers. Selective expression of geminin during the proliferative phase of the cell cycle and its nuclear specificity increase its potential to be used as an alternative marker of proliferation in breast cancer patients.