Marina Parton

A Marker of Homologous Recombination Predicts Pathologic Complete Response to Neoadjuvant Chemotherapy in Primary Breast Cancer

Purpose: To assess the prevalence of defective homologous recombination (HR)-based DNA repair in sporadic primary breast cancers, examine the clincopathologic features that correlate with defective HR and the relationship with neoadjuvant chemotherapy response. Experimental Design: We examined a cohort of 68 patients with sporadic primary breast cancer who received neoadjuvant anthracylcine-based chemotherapy, with core biopsies taken 24 hours after the first cycle of chemotherapy. We assessed RAD51 focus formation, a marker of HR competence, by immunofluorescence in postchemotherapy biopsies along with geminin as a marker of proliferative cells. We assessed the RAD51 score as the proportion of proliferative cells with RAD51 foci. Results: A low RAD51 score was present in 26% of cases (15/57, 95% CI: 15%–40%). Low RAD51 score correlated with high histologic grade (P = 0.031) and high baseline Ki67 (P = 0.005). Low RAD51 score was more frequent in triple-negative breast cancers than in ER- and/or HER2-positive breast cancer (67% vs. 19% respectively; P = 0.0036). Low RAD51 score was strongly predictive of pathologic complete response (pathCR) to chemotherapy, with 33% low RAD51 score cancers achieving pathCR compared with 3% of other cancers (P = 0.011). Conclusions: Our results suggest that defective HR, as indicated by low RAD51 score, may be one of the factors that underlie sensitivity to anthracycline-based chemotherapy. Defective HR is frequent in triple-negative breast cancer, but it is also present in a subset of other subtypes, identifying breast cancers that may benefit from therapies that target defective HR such as PARP inhibitors. Clin Cancer Res; 16(24); 6159–68. ©2010 AACR.

The prognostic significance of Ki67 before and after neoadjuvant chemotherapy in breast cancer

Purpose To compare the prognostic significance of proliferation, as assessed by Ki67 expression, in breast cancer before and after neoadjuvant chemotherapy. Methods A retrospective search of a prospectively maintained clinical database was performed to identify patients treated with neoadjuvant chemotherapy at the Royal Marsden Hospital. The expression of Ki67 was assessed using immunohistochemistry in pre-therapy core-needle biopsy and post-therapy surgical excision specimens. The following factors were considered pre- and post-chemotherapy for their relationship with relapse-free and overall survival: age, menstrual status, T and N stage, pre-therapy operability, Ki67, ER, PgR, HER2, grade, histological subtype, vascular invasion, clinical response, chemotherapy regimen, type of surgery performed, adjuvant therapy, pathological tumour size and nodal involvement. Results In a matched cohort of 103 patients, on multivariate analysis of relapse-free survival, post-therapy Ki67 was the only significant independent prognostic factor. On multivariate analysis for overall survival, both pre- and excision Ki67 were significant independent predictors but the latter showed a stronger prognostic impact. The highest and lowest tertiles of excision Ki67 had different prognosis for both 5-year relapse-free (27% vs. 77%) and overall (39% and 93%) survival. In a cohort of 284 patients with only excision samples, post-therapy Ki67 was a significant independent prognostic factor on multivariate analysis. Conclusion Post-chemotherapy Ki67 is a strong predictor of outcome for patients not achieving a pathological complete response.

Noninvasive Detection of HER2 Amplification with Plasma DNA Digital PCR

Purpose: Digital PCR is a highly accurate method of determining DNA concentration. We adapted digital PCR to determine the presence of oncogenic amplification through noninvasive analysis of circulating free plasma DNA and exemplify this approach by developing a plasma DNA digital PCR assay for HER2 copy number. Experimental Design: The reference gene for copy number assessment was assessed experimentally and bioinformatically. Chromosome 17 pericentromeric probes were shown to be suboptimal, and EFTUD2 at chromosome position 17q21.31 was selected for analysis. Digital PCR assay parameters were determined on plasma samples from a development cohort of 65 patients and assessed in an independent validation cohort of plasma samples from 58 patients with metastatic breast cancer. The sequential probability ratio test was used to assign the plasma DNA digital PCR test as being HER2-positive or -negative in the validation cohort. Results: In the development cohort, the HER2:EFTUD2 plasma DNA copy number ratio had a receiver operator area under the curve (AUC) = 0.92 [95% confidence interval (CI), 0.86–0.99, P = 0.0003]. In the independent validation cohort, 64% (7 of 11) of patients with HER2-amplified cancers were classified as plasma digital PCR HER2–positive and 94% (44 of 47) of patients with HER2-nonamplified cancers were classified as digital PCR HER2–negative, with a positive and negative predictive value of 70% and 92%, respectively. Conclusion: Analysis of plasma DNA with digital PCR has the potential to screen for the acquisition of HER2 amplification in metastatic breast cancer. This approach could potentially be adapted to the analysis of any locus amplified in cancer. Clin Cancer Res; 19(12); 3276–84. ©2013 AACR.

Cell filtration-laser scanning cytometry for the characterisation of circulating breast cancer cells

Epithelial cells may be detected in the circulation of the majority of patients with metastatic breast cancer. Quantification of such presumptive cancer cells might allow for the monitoring of patients with early or late stage disease as an early index of relapse. Additionally, biomarker analysis may allow a more rational approach to therapeutics. We have developed a new method for the detection and characterisation of these cells.

Early changes in apoptosis and proliferation following primary chemotherapy for breast cancer

Patients undergoing primary chemotherapy for invasive breast cancer consented to a core biopsy of the invasive breast primary pre- and 24 h postchemotherapy. The resulting tissue was analysed for apoptosis, Ki67, ER and HER-2 using immunohistochemical techniques. These data were then used to evaluate the relationship between these biological markers and response to chemotherapy and overall survival. Response rate to chemotherapy in this group was 86%, 16 patients (25%) achieved a clinical complete response and 41 (63%) a partial response. Prechemotherapy there was a significant correlation between Ki67 and apoptotic index (AI), r=0.6, (P<0.001). A significant rise in AI (P<0.001), and fall in Ki67 (P=0.002) was seen 24 h following chemotherapy. No relationship was seen between pretreatment AI and clinical response, but higher Ki67 and growth index (Ki67/AI ratio, GI) did correlate with clinical response (both r=0.31, P<0.025). No correlation was seen between the change in AI or Ki67 at 24 h and clinical response or survival. Significant changes in apoptosis and proliferation can be demonstrated 24 h following chemotherapy, but these changes do not relate to clinical response or outcome in this study. Pretreatment proliferation and GI are however predictive of response to chemotherapy in breast cancer.

Studies of apoptosis in breast cancer

Breast cancer is the commonest malignancy in women and comprises 18% of all cancers in women. The United Kingdom has the highest age standardised incidence and mortality from breast cancer in the world.1 Since 1990, death rates from breast cancer have decreased by over 25%, and this is at least in part due to the improved use of adjuvant tamoxifen and chemotherapy. Current research is focused on a greater understanding of the response and resistance to treatment, including the role of apoptosis. Accessibility of the primary tumour makes breast cancer uniquely suitable for such studies. Here we summarise and integrate the data on apoptosis and its role in the development, prognosis, and treatment of breast cancer. Normal breast development is controlled by a balance between cell proliferation and apoptosis, and there is strong evidence that tumour growth is not just a result of uncontrolled proliferation but also of reduced apoptosis. The balance between proliferation and apoptosis is crucial in determining the overall growth or regression of the tumour 2 3 in response to chemotherapy, radiotherapy and, more recently, hormonal treatments. All of these act in part by inducing apoptosis.4–6 Thus it is possible to delineate the biology of individual tumours at the molecular and biochemical level by examining apoptosis and its control and regulation and to exploit these to clinical advantage. Much of this work is still the subject of research. Understanding these relations could allow individually tailored treatments to maximise tumour regression and the efficacy of treatment. It could also help to answer why some tumours fail to respond and thereby indicate new routes of drug development. #### Summary points Increased apoptosis with increased proliferation is associated with malignant tumours Breast tumours with increased apoptosis are more likely to be high grade and negative for oestrogen receptors High …

Role of Cytokine Therapy in 2006 and Beyond for Metastatic Renal Cell Cancer

Metastatic renal cell cancer (mRCC) has a long history as a disease with poor prognosis and limited therapeutic options. Immunotherapy has been the mainstay of treatment since the 1980s, and there have been a number of largely phase II studies examining various schedules of interferon-alpha and interleukin-2 based treatments. With the development of molecular targeted drugs the armentarium against mRCC has significantly expanded and cytokine treatments should be only directed at those most likely to benefit with durable remissions and prolonged survival.

Controversies in the Management of Patients With Breast Cancer: Adjuvant Endocrine Therapy in Premenopausal Women

little more than 20% of all breast cancers occur in women younger than age 50 years,(1) and 60% of these are estrogen receptor (ER)-positive, compared with 80% being ER-positive in women older than the age of 50 years.(2) Tamoxifen has been the mainstay of adjuvant endocrine treatment for many years, but recent developments with aromatase inhibitors in postmenopausal women have stimulated renewed interest in the role of estrogen suppression and its optimal duration as part of premenopausal endocrine therapy. This is an important issue, because such treatment can be associated with physiologic and emotional changes, including sexual dysfunction, urogenital difficulties, hot flashes, and cognitive behavior changes, as well as long-term problems of infertility, osteoporosis, and cardiovascular risks. Many premenopausal women are prepared to tolerate a large number of symptoms even for a relatively small benefit,(3) but for some women, these symptoms may be unacceptable.(4-6) Throughout this article we discuss ER-positive breast cancer because the great weight of evidence shows that ER-poor or ER-negative disease does not respond to endocrine therapy.(7).

The role of ipsilateral breast radiotherapy in management of occult primary breast cancer presenting as axillary lymphadenopathy

AIM To assess the role of ipsilateral breast radiotherapy (IBR) in women with occult primary breast cancer presenting with axillary metastases (OPBC). METHODS Patients with axillary nodal metastases and histological diagnosis of breast cancer without palpable, mammographic or ultrasonographic evidence of a breast primary were identified from a prospectively maintained single institution database. Imaging, surgery, radiotherapy, recurrence and survival data were collected. Patients whose breast cancer primary was detected on MRI (but occult on clinical examination and other imaging) were excluded from the analyses of IBR and outcome, but were included in other exploratory analyses. RESULTS Fifty-five patients were included between 1975 and 2009. Median follow up was 68 months. Twenty patients had breast magnetic resonance imaging (MRI) in addition to other imaging. A primary breast cancer was detected in 7 of these 20. 48/55 patients had no detectable breast primary. 35/48 patients (73%) were treated with radiotherapy to the conserved breast, and 13/48 (27%) with observation. Patients who had IBR had better 5 year local recurrence free survival (LRFS) (84% versus 34%, p<0.001), and relapse free survival (RFS) (64% versus 34%, p=0.05), but no difference in overall survival (OS) (84% versus 85%, p=0.2). There was no difference in 5 year LRFS (80% versus 90%: p=0.3) between patients who received radiation of 50 Gy in 25 fractions versus ≥60 Gy. CONCLUSION Patients with OPBC should be managed with IBR and breast conservation, or mastectomy. Our data suggest it is not necessary to irradiate the breast to more than 50 Gy in 25 fractions.

Trastuzumab beyond progression in HER2-positive advanced breast cancer: The Royal Marsden experience

Background:Recent UK clinical guidance advises against continuing trastuzumab (T) beyond disease progression (PD) in the absence of brain metastases in patients with HER-2 positive (+ve) advanced breast cancer .We have retrospectively evaluated the outcome of patients with HER-2+ve locally advanced (LA) or metastatic breast cancer (MBC) who continued T beyond PD, treated in our unit.Methods:All HER-2+ve patients on our prospectively maintained database with LA or MBC who received T beyond PD after adjuvant or one line of T for advanced disease were assessed for response and outcome. From the timepoint of T continuation beyond PD, we calculated the overall disease control rate, time to progression (TTP), and overall survival (OS).Results:One hundred and fourteen patients with HER-2+ve LA or MBC treated with T beyond PD were identified. The main site of disease was visceral_in 84 (74%) patients. Seventy-six (66%) had one line of chemotherapy before continuation of T beyond PD and 21 (19%) had two or more. Post-progression, 66 (58%) received T combined with chemotherapy. Of the 93 (82%) patients with documented clinical or radiological response evaluation, 67 (59%) were considered as having stable disease or better. The median TTP was 24 weeks (95% CI: 21–28) and the median OS was 19 months (95% CI: 12–24).Conclusion:Our results from an unselected group of patients provide additional evidence that continuation of T beyond PD is of clinical benefit.