Residual proliferative cancer burden to predict long-term outcome following neoadjuvant chemotherapy.

BACKGROUND: The purpose of this study was (i) to test the hypothesis that combining Ki67 with residual cancer burden (RCB) following neoadjuvant chemotherapy, as the residual proliferative cancer burden (RPCB), provides significantly more prognostic information than either alone; (ii) to determine whether also integrating information on ER and grade improves prognostic power. PATIENTS AND METHODS: A total of 220 patients treated with neoadjuvant chemotherapy for primary breast cancer were included in the study. Analyses employed a Cox proportional hazard model. Prognostic indices (PIs) were created adding in Ki67, grade and ER to RCB. Leave-one-out cross-validation was used to reduce bias. The overall change in χ(2) of the best model for each index was used to compare the prognostic ability of the different indices. RESULTS: All PIs provided significant prognostic information for patients with residual disease following neoadjuvant chemotherapy. RPCB (χ(2) = 61.4) was significantly more prognostic than either RCB (χ(2) = 38.1) or Ki67 (χ(2) = 53.8) alone P < 0.001. A PI incorporating RCB, Ki67 grade and ER provided the most prognostic information overall and gave χ(2) = 73.8. CONCLUSIONS: This study provides proof of principle that the addition of post-treatment Ki67 to RCB improves the prediction of long-term outcome. Prediction may be further improved by addition of post-treatment grade and ER and warrants further investigation for estimating post-neoadjuvant risk of recurrence. These indices may have utility in stratifying patients for novel therapeutic interventions after neoadjuvant chemotherapy.

Extreme chromosomal instability forecasts improved outcome in ER-negative breast cancer: a prospective validation cohort study from the TACT trial.

BACKGROUND: Chromosomal instability (CIN) has been shown to be associated with drug resistance and poor clinical outcome in several cancer types. However, in oestrogen receptor (ER)-negative breast cancer we have previously demonstrated that extreme CIN is associated with improved clinical outcome, consistent with a negative impact of CIN on tumour fitness and growth. The aim of this current study was to validate this finding using previously defined CIN thresholds in a much larger prospective cohort from a randomised, controlled, clinical trial. PATIENTS AND METHODS: As a surrogate measurement of CIN, dual centromeric fluorescence in situ hybridisation was performed for both chromosomes 2 and 15 on 1173 tumours from the breast cancer TACT trial (CRUK01/001). Each tumour was scored manually and the mean percentage of cells deviating from the modal centromere number was used to define four CIN groups (MCD1-4), where tumours in the MCD4 group were defined as having extreme CIN. RESULTS: In a multivariate analysis of disease-free survival, with a median follow-up of 91 months, increasing CIN was associated with improved outcome in patients with ER-negative cancer (P trend = 0.03). A similar pattern was seen in ER-negative/HER2-negative cancers (Ptrend = 0.007). CONCLUSIONS: This prospective validation cohort study further substantiated the association between extreme CIN and improved outcome in ER-negative breast cancers. Identifying such patients with extreme CIN may help distinguish good from poor prognostic groups, and therefore support treatment and risk stratification in this aggressive breast cancer subtype.

Guidelines for time-to-event end point definitions in breast cancer trials: results of the DATECAN initiative (Definition for the Assessment of Time-to-event Endpoints in CANcer trials)†.

BACKGROUND: Using surrogate end points for overall survival, such as disease-free survival, is increasingly common in randomized controlled trials. However, the definitions of several of these time-to-event (TTE) end points are imprecisely which limits interpretation and cross-trial comparisons. The estimation of treatment effects may be directly affected by the definitions of end points. The DATECAN initiative (Definition for the Assessment of Time-to-event Endpoints in CANcer trials) aims to provide recommendations for definitions of TTE end points. We report guidelines for randomized cancer clinical trials (RCTs) in breast cancer. PATIENTS AND METHODS: A literature review was carried out to identify TTE end points (primary or secondary) reported in publications of randomized trials or guidelines. An international multidisciplinary panel of experts proposed recommendations for the definitions of these end points based on a validated consensus method that formalize the degree of agreement among experts. RESULTS: Recommended guidelines for the definitions of TTE end points commonly used in RCTs for breast cancer are provided for non-metastatic and metastatic settings. CONCLUSION: The use of standardized definitions should facilitate comparisons of trial results and improve the quality of trial design and reporting. These guidelines could be of particular interest to those involved in the design, conducting, reporting, or assessment of RCT.

Biomarker changes associated with the development of resistance to aromatase inhibitors (AIs) in estrogen receptor-positive breast cancer.

BACKGROUND: The purpose of this study was to identify any differences in key biomarkers associated with estrogen action between biopsies taken at diagnosis and at recurrence or progression during treatment with an aromatase inhibitor (AI). PATIENTS AND METHODS: Patients were retrospectively identified from a clinical database as having relapsed or progressed during AI treatment. Immunohistochemistry was carried out against estrogen receptor (ER), progesterone receptor (PgR), human epidermal growth factor receptor 2 (HER2), insulin-like growth factor type-1 receptor (IGF1R), insulin receptor substrate-1 (IRS-1), stathmin, phosphatase and tensin homolog and Ki67. RESULTS: Fifty-five pairs of samples were identified with ER- and/or PgR-positive diseases. Four (7%) patients were ER-negative at progression. Overall, PgR levels were lower in the recurrence sample, but 35% of cases remained positive. IGF1R levels decreased significantly. There were no substantial changes in HER2, IRS-1 or stathmin levels to indicate a role in resistance. Higher Ki67 levels at resistance indicate more proliferative disease. CONCLUSIONS: The phenotype of AI-recurrent lesions shows high between-tumour heterogeneity. There is evidence of an increase in Ki67, a reduction in IGF1R and a loss of ER expression in some individuals and some activation of growth factor signalling pathways that may explain resistance in individuals and merit treatment targeted to those pathways. Biopsy at recurrence will be necessary to identify the relevant target for individuals.

Assessment of microtubule-associated protein (MAP)-Tau expression as a predictive and prognostic marker in TACT; a trial assessing substitution of sequential docetaxel for FEC as adjuvant chemotherapy for early breast cancer.

The TACT trial is the largest study assessing the benefit of taxanes as part of adjuvant therapy for early breast cancer. The goal of this translational study was to clarify the predictive and prognostic value of Tau within the TACT trial. Tissue microarrays (TMA) were available from 3,610 patients. ER, PR, HER2 from the TACT trial and Tau protein expression was determined by immunohistochemistry on duplicate TMAs. Two parallel scoring systems were generated for Tau expression ('dichotomised' vs. 'combined' score). The positivity rate of Tau expression was 50 % in the trial population (n = 2,483). Tau expression correlated positively with ER (p < 0.001) and PR status (p < 0.001); but negatively with histological grade (p < 0.001) and HER2 status (p < 0.001). Analyses with either scoring systems for Tau expression demonstrated no significant interaction between Tau expression and efficacy of docetaxel. Contrary to the hypothesis that taxane benefit would be enriched in Tau negative/low patients, the only groups with a suggestion of a reduced event rate in the taxane group were the HER2-positive, Tau positive subgroups. Tau expression was seen to be a prognostic factor on univariate analysis associated with an improved DFS, independent of the treatment group (p < 0.001). It had no prognostic value in ER-negative tumours and the weak prognostic effect of Tau in ER-positive tumours (p = 0.02) diminished, when considering ER as an ordinal variable. On multivariable analyses, Tau had no prognostic value in either group. In addition, no significant interaction between Tau expression and benefit from docetaxel in patients within the PR-positive and negative subsets was seen. This is now the second large adjuvant study, and the first with quantitative analysis of ER and Tau expression, failing to show an association between Tau and taxane benefit with limited utility as a prognostic marker for Tau in ER-positive early breast cancer patients.

Enhanced expression of the PDGFR/Abl signaling pathway in aromatase inhibitor-resistant breast cancer.

BACKGROUND: We have found that the platelet-derived growth factor receptor (PDGFR)/Abl signaling pathway is up-regulated as a determinant of the acquisition of resistance to estrogen deprivation in vitro. We aimed to determine its clinical relevance in aromatase inhibitor (AI)-resistant breast cancer. PATIENTS AND METHODS: We identified a cohort of 45 patients with estrogen receptor-positive breast cancer who had been treated with an AI, subsequently relapsed and had biopsy material available from both the presentation and post-AI recurrent lesion. PDGFRα, PDGFRß and Abl expression was assessed in formalin-fixed paraffin-embedded sections. RESULTS: Tumor protein expression of PDGFRα (1.39-fold, P=0.0065), PDGFRß (4.32-fold, P=0.006) and Abl (1.8-fold, P=0.001) was increased at the point of relapse. Tumor and stromal expression of PDGFRα as well as PDGFRß was significantly correlated in pre-treatment and relapse samples. High post-treatment tumor and stromal PDGFRß levels were associated with a short time to treatment failure (TTF). Expression of PDGFRα in relapsing tumor specimens was correlated with Abl expression and Ki67 levels. Furthermore, changes in Abl correlated significantly with changes in ER expression. CONCLUSIONS: These clinical data support a role for enhanced PDGF/Abl signaling in AI-resistant disease and provide a rationale for targeting the pathway in endocrine-resistant breast cancer.

Assessment of the contribution of the IHC4+C score to decision making in clinical practice in early breast cancer.

BACKGROUND: The immunohistochemical (IHC) 4+C score is a cost-effective prognostic tool that uses clinicopathologic factors and four standard IHC assays: oestrogen receptor (ER), PR, HER2 and Ki67. We assessed its utility in personalising breast cancer treatment in a clinical practice setting, through comparison with Adjuvant! Online (AoL) and the Nottingham Prognostic Index (NPI). METHODS: We prospectively gathered clinicopathologic data for postmenopausal patients with hormone receptor-positive, HER2-negative, N0-3 resected early breast cancer treated consecutively at our institution. We retrospectively calculated and compared prognostic scores. The primary endpoint was the proportion of patients reclassified from AoL-defined intermediate-risk by application of the IHC4+C score. RESULTS: The median age of the 101 patients included in the analysis was 63. In all, 15 of the 26 patients classified as intermediate-risk by AoL were reallocated to a low-risk group by application of the IHC4+C score and no patient was reclassified as high-risk group. Of the 59 patients classified as intermediate-risk group by the NPI, 24 were reallocated to a low-risk group and 13 to a high-risk group. CONCLUSION: IHC4+C reclassifies more than half of the patients stratified as being in intermediate-risk group by the AoL and NPI. The use of IHC4+C may substantially improve decision-making on adjuvant chemotherapy.

Prediction of early death among patients enrolled in phase I trials: development and validation of a new model based on platelet count and albumin.

BACKGROUND: Selecting patients with 'sufficient life expectancy' for Phase I oncology trials remains challenging. The Royal Marsden Hospital Score (RMS) previously identified high-risk patients as those with ≥ 2 of the following: albumin <35 g l(-1); LDH > upper limit of normal; >2 metastatic sites. This study developed an alternative prognostic model, and compared its performance with that of the RMS. METHODS: The primary end point was the 90-day mortality rate. The new model was developed from the same database as RMS, but it used Chi-squared Automatic Interaction Detection (CHAID). The ROC characteristics of both methods were then validated in an independent database of 324 patients enrolled in European Organization on Research and Treatment of Cancer Phase I trials of cytotoxic agents between 2000 and 2009. RESULTS: The CHAID method identified high-risk patients as those with albumin <33 g l(-1) or ≥ 33 g l(-1), but platelet counts ≥ 400.000 mm(-3). In the validation data set, the rates of correctly classified patients were 0.79 vs 0.67 for the CHAID model and RMS, respectively. The negative predictive values (NPV) were similar for the CHAID model and RMS. CONCLUSION: The CHAID model and RMS provided a similarly high level of NPV, but the CHAID model gave a better accuracy in the validation set. Both CHAID model and RMS may improve the screening process in phase I trials.

Relationship between estrogen receptor, progesterone receptor, HER-2 and Ki67 expression and efficacy of aromatase inhibitors in advanced breast cancer.

BACKGROUND: Surprisingly few data are published on the relevance of even commonly used biomarkers of response to aromatase inhibitors (AIs) in advanced breast cancer. Here, we aim to determine the effectiveness of AIs in that setting according to quantitative levels of estrogen receptor (ER), progesterone receptor (PgR) and Ki67 or human epithelial growth factor receptor-2 (HER-2) status. PATIENTS AND METHODS: ER, PgR, HER-2 and Ki67 protein expressions were centrally assessed in 177 archival formalin-fixed paraffin-embedded primary or locally recurrent breast tumours from women who subsequently received AI treatment of advanced disease. RESULTS: Among ER-positive patients (n = 146), higher PgR, but not ER, levels were associated with increased time to AI treatment failure (TTF). Higher Ki67 staining was associated with decreased TTF. ER-positive/HER-2-positive patients showed a non-significant trend for decreased TTF compared with ER-positive/HER-2-negative patients. PgR level, but not Ki67, remained a significant predictor of TTF in multivariate analysis of ER-positive patients. CONCLUSIONS: Higher PgR and Ki67 levels are significantly associated with increased and decreased TTF, respectively, in ER-positive patients receiving AI treatment of advanced disease. The higher proliferation seen in PgR-negative tumours does not explain the poorer clinical responsiveness of this subgroup.

Multicentric breast cancer: clonality and prognostic studies.

Clonality of multicentric breast cancer has traditionally been difficult to assess. We aimed to assess this using analysis of TP53 status (expression and mutation status). These results were then incorporated into an analysis of prognostic factors in multicentric tumours in a 10-year follow up study. Clonal status of multicentric breast cancer foci (n = 88 foci) was determined by immunohistochemical and molecular studies of TP53 in a total of 40 patients. Prognostic factors from these patients were also compared with 80 age- and stage-matched controls with unicentric breast cancer from the Royal Marsden NHS Foundation Trust Breast Cancer Database. Our results indicate that multicentric breast cancer foci were polyclonal within an individual patient in at least 10 patients (25%) with respect to immunohistochemical staining and in four patients (10%) with respect to abnormal band shifts on single strand conformational polymorphism (SSCP) molecular analysis. No individual variable was predictive of multicentric or unicentric disease. However, there was a worse overall survival in the multicentric breast cancer patients in whom at least two cancer foci stained positively on TP53 immunohistochemistry compared with the matched control group (P = 0.04). In conclusion, these results suggest that a proportion of multicentric breast cancer foci are polyclonal with respect to TP53 status and that TP53 over-expression predicts for a poorer prognosis in multicentric breast cancer.

Inflammatory cytokines and aromatase inhibitor-associated musculoskeletal syndrome: a case-control study.

BACKGROUND: The aromatase inhibitor (AI)-associated musculoskeletal syndrome (AIMSS) occurs in approximately 50% of AI-treated patients. Inflammatory mediators are associated with oestrogen signalling and may change with oestrogen depletion. We hypothesised that AIMSS may be associated with changes in circulating inflammatory markers. METHODS: Patients with breast cancer were enrolled in a trial of adjuvant AI therapy. Changes in pain and function during therapy were assessed prospectively. We selected 30 cases with AIMSS and 22 controls without AIMSS, matched for demographics and prior therapy. Serum samples collected at baseline and during treatment were assayed for multiple inflammatory cytokines and lipid mediators using multiplex assays. RESULTS: Before AI therapy, mean serum concentrations of 6 of 36 assayed factors were statistically significantly lower in cases than controls (all P<0.003). No statistically significant changes during AI therapy relative to pre-treatment were observed between cases and controls for any of the inflammatory markers tested. CONCLUSION: AIMSS is probably not associated with a systemic inflammatory response. Pre-treatment cytokine levels may predict for development of AIMSS.

A randomised comparative trial of infusional ECisF versus conventional FEC as adjuvant chemotherapy in early breast cancer: the TRAFIC trial.

BACKGROUND: The epirubicin with cisplatin and infusional 5-fluorouracil (5-FU) (ECisF) regimen was found to be highly active in the treatment of metastatic breast cancer and as neoadjuvant therapy. The UK TRAFIC (trial of adjuvant 5-FU infusional chemotherapy) trial (CRUK/95/007) compared this schedule with 5-FU, epirubicin and cyclophosphamide (FEC60) as adjuvant therapy in patients with early breast cancer. METHODS: In this multicentre, open-label, phase III randomised controlled trial, 349 women were randomly assigned to receive i.v. ECisF [epirubicin 60 mg/m(2), day 1, cisplatin 60 mg/m(2), day 1 and 5-FU 200 mg/m(2) by daily 24-h infusion (n = 172)] or FEC [5-FU 600 mg/m(2), day 1, epirubicin 60 mg/m(2), day 1 and cyclophosphamide 600 mg/m(2), day 1 (n = 177)]. Both treatments were delivered every 3 weeks for six cycles. The primary end point was relapse-free interval (RFI). TRAFIC is registered as an International Standard Randomised Controlled Trial (ISRCTN 83324925). RESULTS: All randomised patients were included in the intent-to-treat population. With a median follow-up of 112 months, there was no significant difference in RFI between the treatment groups [hazard ratio 0.84 (95% confidence interval 0.60-1.19); P = 0.33]. Toxic effects were more frequent in patients allocated to ECisF. CONCLUSIONS: While limited by size, TRAFIC has long follow-up. No evidence of a clinically worthwhile benefit for the infusional treatment compared with standard treatment was observed which would justify further investigation or widespread use.

Diagnostic precision of CT in local staging of colon cancers: a meta-analysis.

AIM: To determine the accuracy of computed tomography (CT) in detecting disease with invasion beyond the muscularis propria (MP) and malignant lymph nodes. MATERIALS AND METHODS: A literature search of Ovid, Embase, the Cochrane database, and Medline using Pubmed, Google Scholar and Vivisimo search engines was performed to identify studies reporting on the accuracy of CT to predict the staging of colonic tumours. Publication bias was demonstrated by Funnel plots. The sensitivity, specificity, and diagnostic odds ratio (DOR) were calculated using a bivariate random effects model and hierarchical summary operating curves (HSROC) were generated. RESULTS: Nineteen studies fulfilled all the necessary inclusion criteria. The pooled sensitivity, specificity, DOR for detection of tumour invasion were 86% (95% CI: 78-92%); 78% (95% CI: 71-84%); 22.4 (95% CI: 11.9-42.4). Similarly, the values for nodal detection were 70% (95% CI: 63-73%); 78% (95% CI: 73-82%); 8.1(95% CI: 4.7-14.1). In the subgroup analysis, the best results were obtained in studies utilizing multidetector CT (MDCT). CONCLUSION: Preoperative staging CT accurately distinguishes between tumours confined to the bowel wall and those invading beyond the MP; however, it is significantly poorer at identifying nodal status. MDCT provides the best results.

Discordance between core needle biopsy (CNB) and excisional biopsy (EB) for estrogen receptor (ER), progesterone receptor (PgR) and HER2 status in early breast cancer (EBC).

BACKGROUND: Analysis of estrogen receptor (ER), progesterone receptor (PgR) and HER2 status in early breast cancer (EBC) is increasingly being conducted in core needle biopsies (CNBs) taken at diagnosis but the concordance with the excisional biopsy (EB) is poorly documented. PATIENTS AND METHODS: Patients with EBC presenting to The Royal Marsden Hospital from June 2005 to September 2007 who had CNB and subsequent EB were included. ER and PgR were determined by immunohistochemistry (IHC) and graded from 0 to 8 (Allred score). HER2 was determined by IHC and scored from 0 to 3+. FISH analysis was carried out in HER2 2+ cases and in discordant cases. RESULTS: In all, 336 pairs of samples were compared. ER was positive in 253 CNBs (75%) for 255 EBs (76%) and was discordant in six patients (1.8%). PgR was positive in 221 CNBs (66%) and 227 (67.6%) EBs being discordant in 52 cases (15%). HER2 was positive in 41 (12.4%) of the 331 CNBs in which it was determined compared with 44 (13.3%) EBs and discordant in four cases (1.2%). CONCLUSIONS: CNB can be used with confidence for ER and HER2 determination. For PgR, due to a substantial discordance between CNB and EB, results from CNB should be used with caution.

A feasibility study of sequential doublet chemotherapy comprising carboplatin-doxorubicin and carboplatin-paclitaxel for advanced endometrial adenocarcinoma and carcinosarcoma.

BACKGROUND: Platinum compounds, taxanes and anthracyclines provide the major effective drug classes in the treatment of advanced and recurrent endometrial cancer and carcinosarcoma. PATIENTS AND METHODS: A total of 52 women with advanced or recurrent endometrial cancer and carcinosarcoma were treated with four cycles of carboplatin area under the curve (AUC) 5 and doxorubicin (50 mg/m(2)) for four cycles before or after four cycles of carboplatin AUC5 and paclitaxel (175 mg/m(2)) with each cycle administered at 21-day intervals. RESULTS: Thirty-seven patients (71.2%) completed all planned treatment. Excluding six patients who did not complete treatment for non-drug-related causes, 80.4% completed all planned treatment. Three hundred and seventy-one treatment cycles were administered and 303 (81.7%) occurred on time. Common Toxicity Criteria grade 3/4 haematological toxic effects, particularly neutropenia and thrombocytopenia, were the predominant cause of treatment delays and dose reductions. A low incidence of grade 3 neurotoxicity and no cardiac toxicity were observed. The overall response rates for patients with evaluable disease were 82.1% and 66.7% for endometrial and carcinosarcoma, respectively. At a median follow-up of 21 months, the median progression-free survival for the endometrial adenocarcinoma and carcinosarcoma cohorts were 15.3 and 12.0 months, respectively. CONCLUSION: This regimen is generally well tolerated with encouraging efficacy.

Circulating tumour cell (CTC) counts as intermediate end points in castration-resistant prostate cancer (CRPC): a single-centre experience.

BACKGROUND: The purpose of this study was to evaluate the association of circulating tumour cell (CTC) counts, before and after commencing treatment, with overall survival (OS) in patients with castration-resistant prostate cancer (CRPC). EXPERIMENTAL DESIGN: A 7.5 ml of blood was collected before and after treatment in 119 patients with CRPC. CTCs were enumerated using the CellSearchSystem. RESULTS: Higher CTC counts associated with baseline characteristics portending aggressive disease. Multivariate analyses indicated that a CTC >or=5 was an independent prognostic factor at all time points evaluated. Patients with baseline CTC >or=5 had shorter OS than those with <5 [median OS 19.5 versus >30 months, hazard ratio (HR) 3.25, P=0.012]; patients with CTC >50 had a poorer OS than those with CTCs 5-50 (median OS 6.3 versus 21.1 months, HR 4.1, P<0.001). Patients whose CTC counts reduced from >or=5 at baseline to <5 following treatment had a better OS compared with those who did not. CTC counts showed a similar, but earlier and independent, ability to time to disease progression to predict OS. CONCLUSION: CTC counts predict OS and provide independent prognostic information to time to disease progression; CTC dynamics following therapy need to be evaluated as an intermediate end point of outcome in randomised phase III trials.

Epirubicin, cisplatin and protracted venous infusion 5-Fluorouracil chemotherapy for advanced salivary adenoid cystic carcinoma.

AIMS: Adenoid cystic carcinoma (ACC) is a rare tumour that usually arises in the salivary glands. Initial management is surgery often combined with adjuvant radiotherapy. Chemotherapy is reserved for treatment of symptomatic recurrence. We evaluated the combination of epirubicin, cisplatin and protracted venous infusion 5-fluorouracil (ECF) in the management of ACC. MATERIALS AND METHODS: Patients referred for treatment of advanced, symptomatic ACC were considered. The drugs given were epirubicin 50 mg/m(2) 3-weekly, cisplatin 60 mg/m(2) 3-weekly and protracted venous infusion 5-fluorouracil 200 mg/m(2)/day. RESULTS: Eight patients (median age 46 years) received a median of five cycles of chemotherapy. All patients had had previous surgery, seven had had previous radiotherapy and one had had previous chemotherapy. One patient showed a partial response (duration 34 months) and five showed stable disease (median duration 13.6 months [6.8-15.9+ months]). Median survival was 27 months (3.5-62.3 months). CONCLUSIONS: The activity of ECF in ACC of the head and neck seems to be similar to the combination of cisplatin and 5-fluorouracil and single-agent epirubicin.

Cancer Biology and Survival Analysis in Cancer Trials: Restricted Mean Survival Time Analysis versus Hazard Ratios.

Hazard ratios are commonly used when comparing survival between two groups and make the assumption that the relative event rates do not change markedly during follow-up, i.e. that event rates are proportional. However, there is currently debate about the use of the proportional hazards assumption to summarise the treatment effect in survival analysis compared with restricted mean survival time (RMST) analysis, particularly in cancer trials. In many situations it is unrealistic to assume that relative event rates in two groups will be proportional throughout follow-up and, hence, RMST analysis, which does not make this assumption, may be preferable. Several benefits of the latter approach have been identified but the biological perspective is not often discussed. Biological features such as the patterns of tumour growth and response can also contribute to assessing the relative merit of these two methods; such biological considerations are the subject of this paper. The observation that the most commonly observed approximation to the underlying distribution of time to event data, the lognormal distribution, does not reliably show proportional hazards in the comparison of two groups, lends weight to a statistical approach that is not based on proportional hazards. The proportional hazards assumption should be viewed more critically when estimating treatment effects. An optimum approach may be to include both proportional hazards analysis and RMST analysis when comparing time to event endpoints.

Clinical outcome and service implications of screening women at increased breast cancer risk from a family history.

INTRODUCTION: The value of special screening for women at moderate breast cancer risk with a family history of breast cancer remains controversial. Little is known about recall rates, false negative outcomes and the impact on clinical service. Despite this, surveillance programmes within breast units have been established in the United Kingdom. PATIENTS AND METHODS: In our institution, screening of women at moderate (lifetime risk, 17-30%) and high risk (>30%) consisted of annual clinical examination and mammography from the age of 35 years. The active study period ran for four months and each patient was followed through a further screening cycle (whole study period), providing information on interval cancers and detection at the subsequent screen. RESULTS: One thousand one hundred and thirty-two women attended for their incident screen: 137 at high risk, 803 at moderate risk and 192 at standard risk. The median age at cancer diagnosis in the moderate risk group was 54 (range, 45-68) years and the high-risk group 51 (46-52) years, compared to 63 (45-69) years in the standard risk group. Seven cancers were diagnosed during the four-month active study period. Two patients were diagnosed with interval cancers and eight at the next screen, giving a cancer incidence in the whole study period of 17/1132 (1.5%). Thirteen patients had invasive cancer and four had ductal carcinoma in situ (DCIS) The median invasive tumour size was 15 had (range, 7-28)mm and the median DCIS size was 4 (2-30)mm. 10/13 (76.9%) invasive cancers were < or =20mm and 2/13 patients (15.4%) with invasive cancer were lymph node positive. The sensitivity and specificity of mammography were 85.7% and 98.8%, respectively. The mammogram recall rate was 27.6 per 1000. The benign to malignant surgery ratio was 8:17. CONCLUSION: Screening women at increased breast cancer risk is effective. Early detection and recall rates are comparable to that of older women attending the British National Breast Screening Programme.