Prognostic value of EndoPredict test in patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative primary breast cancer screened for the randomized, double-blind, phase III UNIRAD trial

BACKGROUND

The purpose of this study was to evaluate the prognostic value of the multigene EndoPredict test in prospectively collected data of patients screened for the randomized, double-blind, phase III UNIRAD trial, which evaluated the addition of everolimus to adjuvant endocrine therapy in high-risk, hormone receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative early breast cancer.

PATIENTS AND METHODS

Patients were classified into low or high risk according to the EPclin score, consisting of a 12-gene molecular score combined with tumor size and nodal status. Association of the EPclin score with disease-free survival (DFS) and distant metastasis-free survival (DMFS) was evaluated using Kaplan-Meier estimates. The independent prognostic added value of EPclin score was tested in a multivariate Cox model after adjusting on tumor characteristics.

RESULTS

EndoPredict test results were available for 768 patients: 663 patients classified as EPclin high risk (EPCH) and 105 patients as EPclin low risk (EPCL). Median follow-up was 70 months (range 1-172 months). For the 429 EPCH randomized patients, there was no significant difference in DFS between treatment arms. The 60-month relapse rate for patients in the EPCL and EPCH groups was 0% and 7%, respectively. Hazard ratio (HR) supposing continuous EPclin score was 1.87 [95% confidence interval (CI) 1.4-2.5, P < 0.0001]. This prognostic effect remained significant when assessed in a Cox model adjusting on tumor size, number of positive nodes and tumor grade (HR 1.52, 95% CI 1.09-2.13, P = 0.0141). The 60-month DMFS for patients in the EPCL and EPCH groups was 100% and 94%, respectively (adjusted HR 8.10, 95% CI 1.1-59.1, P < 0.0001).

CONCLUSIONS

The results confirm the value of EPclin score as an independent prognostic parameter in node-positive, hormone receptor-positive, HER2-negative early breast cancer patients receiving standard adjuvant treatment. EPclin score can be used to identify patients at higher risk of recurrence who may warrant additional systemic treatments.

Associations between the ultrasound features of invasive breast cancer and breast cancer specific survival

AIM

To assess whether ultrasound features of breast cancer are associated with breast cancer specific survival (BCSS).

MATERIALS AND METHODS

Within a single breast service, data was collected prospectively (April 2010-April 2012) from 319 consecutive women (mean age 63 years) with 335 ultrasound-visible invasive breast cancers. Ultrasound features were evaluated retrospectively from the recorded images according to the Breast Imaging Reporting and Data System (BI-RADS) lexicon by a radiologist blinded to outcomes. Survival and cause of death were ascertained from local and national sources. Kaplan-Meier survival curves were generated, and statistical significance tested using the log-rank test.

RESULTS

Mean follow-up in those alive was 80.9 months. Thirty breast cancer deaths and 45 non-breast cancer deaths occurred. Five-year BCSS in the presence of distal acoustic enhancement was 76% compared to 88%, 96%, and 100% for those with distal shadowing, no distal effect or combined effect respectively (p<0.0002). Patients with sonographic skin involvement had 73% 5-year BCSS compared to 92% for no skin involvement (p<0.0001). Focal oedema was associated with 56% 5-year BCSS compared to 89% for those without (p=0.0002). A significant association was demonstrated between ultrasound tumour size and BCSS (p<0.0001). At multivariate analysis, skin changes, distal enhancement, and focal oedema maintained prognostic significance.

CONCLUSION

Distal enhancement, focal oedema, and skin involvement have strong associations with breast cancer death. These factors could be taken into account, along with lesion size and other commonly used preoperative prognostic features, when considering management of women with breast cancer.

Preoperative prediction of margin requirement following a core biopsy result suggestive of a phyllodes tumour

AIM

To determine if imaging features of lesions with a core biopsy suggestive of a phyllodes tumour can be used to identify which lesions require surgical excision with margins.

MATERIALS AND METHODS

Thirty-one lesions were identified from a prospective database of ultrasound visible masses. Demographic, mammographic, and ultrasound features were assessed while blinded to surgical outcome. Features of those lesions requiring a margin and those that did not were compared. Statistical significance was established using the chi-square test and receiver operating characteristic (ROC) curves.

RESULTS

Thirteen lesions (42%) required a margin and 18 lesions (58%) did not. Features found significantly more frequently in those requiring a margin were a poorly defined margin on mammography (7/9 [78%] versus 4/13 [31%]; p=0.04) and at ultrasound, an irregular margin (8/13 [62%] versus 3/18 [17%]; p=0.01), micro-lobulations (7/13 [54%] versus 3/18 [17%]; p=0.028), mixed echogenicity (9/13 [69%] versus 1/18 [6%]; p=0.0002), echogenic clefts (6/13 [46%] versus 1/18 [6%]; p=0.007), posterior enhancement (9/11 [82%] versus 6/18 [33%]; p=0.01), large size (p=0.003) and stiffness at shear-wave elastography (p=0.026). All six screen-detected lesions were benign.

CONCLUSIONS

There are multiple preoperative features that can be used to guide surgical management of lesions with a preoperative core biopsy result suggestive of a phyllodes tumour.

Abstract P2-08-02: Interaction of PIK3CA mutation subclasses with response to preoperative treatment with the PI3K inhibitor pictilisib in patients with estrogen receptor-positive breast cancer

Background: Although preclinical data suggest that combining PI3K inhibitors with endocrine therapy may overcome resistance, results from randomized clinical trials have failed to identify a subgroup of patients that derive a substantial benefit. This preoperative window study assessed whether adding the PI3K inhibitor pictilisib can increase the anti-tumor effects of anastrozole in primary breast cancer and aimed to identify the most appropriate patient population for combination therapy.

Methods: In this randomized, open-label, phase 2 study, 167 postmenopausal women with newly diagnosed, operable, ER-positive, HER2-negative breast cancers were recruited. Participants were randomly allocated (2:1, favoring the combination) to two-weeks of preoperative treatment with anastrozole 1 mg once daily or the combination of anastrozole 1mg with pictilisib 260 mg once daily. The primary endpoint was inhibition of tumor cell proliferation, as measured by change in Ki-67 protein expression between tumor samples taken before and at the end of treatment. Secondary endpoints include induction of apoptosis (Caspase3) and safety. Comprehensive biomarkers analyses included targeted NGS of a comprehensive cancer panel of &gt;400 genes (Ampliseq Comprehensive Cancer panel), copy number variation analyses, and pre- and post-treatment reverse-phase protein arrays (RPPA) and RNA profiling (NanoString nCounter platform).

Results:There was significantly greater geometric mean Ki67 suppression of 82.5% (90% CI, 78.3%-85.8%) for the combination vs 70.7% (61.0%-78.0%) for anastrozole [geometric mean ratio (combination/ anastrozole) 0.60 (0.58-0.85);p=0.01]. Higher baseline Ki67, Luminal B status and/or negative PR status were associated with increased benefit from adding pictilisib. A significant interaction was observed between PIK3CA mutation subtypes [helical domain mutations (HD), kinase domain mutations (KD), wildtype (WT)] and mean Ki67 suppression; the combination/anastrozole geometric mean ratio of Ki67 suppression was 0.48 (0.27-0.84; p=0.02) for patients with HD mutations and 0.63 (0.39–1.0; p=0.05) for patients with PIK3Ca WT, compared to 1.17 (0.57–2.41; p=0.64) for patients with KD mutations. This was largely due to patients with HD mutations showing a particularly poor response to anastrozole alone [mean Ki67 suppression 53.9% (9.5%-76.5%)], that was reversed by the addition of pictilisib [mean Ki-67 suppression 78.1% (71.0%-83.4%)]. On the other hand, patients with KD mutations responded well to anastrozole alone [mean Ki-67 suppression 77.7% (57.0%-88.4%)] and showed no benefit from the addition of pictilisib [mean Ki-67 suppression 73.9% (59.8%-83.0%)]. There was no significant difference in induction of apoptosis between treatment groups. Comprehensive pre- and post-treatment biomarkers analyses will be presented.

Conclusions: Adding pictilisib to anastrozole significantly increases the anti-proliferative response to preoperative treatment with anastrozole. A significant interaction was observed between PIK3CA mutation subtypes, with patients with helical domain mutations showing a particularly poor response to anastrozole alone that was reversed by the addition of pictilisib.

Citation Format: Schmid P, Pinder S, Wheatley D, Zummit C, Macaskill EJ, Hu J, Price R, Bundred N, Hadad S, Shia A, Sarker S-J, Lim L, Mousa K, O'Brien C, Wilson TR, Lackner MR, Gendreau S, Gazinska P, Korbie D, Trau M, Mainwaring P, Thompson A, Purushotham A. Interaction of PIK3CA mutation subclasses with response to preoperative treatment with the PI3K inhibitor pictilisib in patients with estrogen receptor-positive breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-08-02.

Percutaneous sentinel node removal using a vacuum-assisted needle biopsy in women with breast cancer: a feasibility and acceptability study

AIMS

To assess the feasibility and acceptability of large-gauge percutaneous removal of the axillary sentinel lymph node (SLN) using dual gamma probe and ultrasound guidance.

MATERIALS AND METHODS

Technetium nanocolloid was administered the day before surgery. On the day of surgery, potential SLNs were identified with gamma probe and ultrasound scanning. A 7 G vacuum-assisted biopsy (VAB) device was inserted percutaneously deep to the target node and the node(s) removed. The gamma probe was used to confirm removal of radiolabelled tissue. At surgery, any residual radiolabelled or blue nodes were removed. Morbidity was assessed via (1) a pain questionnaire immediately after the percutaneous procedure, (2) relevant items from the FACT B+4 questionnaire 7-10 days after surgery, and (3) case note review 1 month after surgery.

RESULTS

Twenty-two patients consented and 20 patients underwent the procedure. Radiolabelled nodal tissue was obtained in 18/20 (90%). The mean procedure time was 11 minutes. Four of 18 patients had metastatic disease identified in the VAB excision tissue with 100% sensitivity for axillary metastasis. At axillary surgery, additional intact SLN or fragments were found in 14 patients. No additional metastatic disease was found at surgery. One patient suffered a pneumothorax during instillation of local anaesthetic. The median pain score was 10/100 by visual analogue scale. Immediate post-procedure haematoma was common (14 of 20) and prolonged manual compression frequent.

CONCLUSION

VAB removal of sentinel nodes using dual scanning is feasible. Although preliminary sensitivity and specificity levels are encouraging, complications may discourage widespread implementation.

Association between underestimation of tumour size by imaging and incomplete excision in breast-conserving surgery for breast cancer

Background

Completeness of excision is the most important factor influencing local recurrence after breast-conserving surgery (BCS). The aim of this case–control study was to determine factors influencing incomplete excision in patients undergoing BCS.

Methods

Women with invasive breast cancer treated by BCS between 1 June 2008 and 31 December 2009 were identified from a prospectively collected database in the Edinburgh Breast Unit. The maximum size of the tumour, measured microscopically, was compared with the size estimated before operation by mammography and ultrasound imaging. A multivariable analysis was performed to investigate factors associated with incomplete excision.

Results

The cohort comprised 311 women, of whom 193 (62·1 per cent) had a complete (CE group) and 118 (40·7 per cent) an incomplete (IE group) excision. Mammography underestimated tumour size in 75·0 per cent of the IE group compared with 40·7 per cent of the CE group (P &lt; 0·001). Ultrasound imaging underestimated tumour size in 82·5 per cent of the IE group compared with 56·5 per cent of the CE group (P &lt; 0·001). The risk of an incomplete excision was greater when mammography or ultrasonography underestimated pathological size: odds ratio (OR) 4·38 (95 per cent c.i. 2·59 to 7·41; P &lt; 0·001) for mammography, and OR 3·64 (2·03 to 6·54; P &lt; 0·001) for ultrasound imaging. For every 1-mm underestimation of size by mammography and ultrasonography, the relative odds of incomplete excision rose by 10 and 14 per cent respectively.

Conclusion

Underestimation of tumour size by current imaging techniques is a major factor associated with incomplete excision in women undergoing BCS.

P3-12-04: Involved Anterior Margins after Breast Conserving Surgery: Is Re-Excision Required?

Background: Complete tumour excision in breast conserving surgery (BCS) is critical for successful treatment; involved circumferential resection margins are associated with increased disease recurrence. However, the importance of an involved anterior margin is less clear. The purpose of this study was to audit an aggressive approach to involved anterior margins and hence assess whether anterior margin re-excision yields clinical benefit.

Material and Methods: A retrospective case note and pathology review was performed for all patients who underwent BCS between 2006 and 2010 through a single cancer centre. An involved margin was defined as &lt;1mm clearance of invasive or in situ breast cancer. Results: 1667 patients underwent BCS for invasive and/or in-situ disease, of whom 114 (6.8%) underwent re-excision, most commonly for mixed invasive and in-situ pathology. The annual re-excision rate rose significantly (p&lt;0.001), with no change in whole tumour diameter, specimen weight or specimen volume. A total of 170 involved margins were identified: most commonly the anterior margin (59 margins, 30.6%) followed by the posterior (39 22.9%) or inferior (31, 18.3%) margin. Patients with anterior margin involvement were more likely to have grade 3 invasive disease (p=0.0323) but less likely to have residual disease found at re-excision (2/49 vs. 32/101 margins, p=0.0033); there were no differences when in-situ characteristics were compared.

Conclusions: Re-excision of involved anterior margins rarely excises residual disease and may be unnecessary. Multidisciplinary teams should consider whether further therapy for an involved anterior margin is required on a patient by patient basis.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-12-04.

The mammalian target of rapamycin inhibitor everolimus (RAD001) in early breast cancer: results of a pre-operative study

mTOR plays a key role in tumor cell cycle control, proliferation, and survival. RAD001 (everolimus) is a novel macrolide that inhibits mTOR and thus downstream signaling pathways. 31 post-menopausal women with early breast cancer were given 5 mg RAD001 once daily for 14 days prior to surgery. Biopsies were taken at diagnosis and at surgery (post 14 days of treatment) and assessed for immunohistochemical changes in proliferation (Ki67), apoptosis (active caspase-3), p-AKT (s473), p-S6 (s235/236 and s240/244), p-mTOR (s2448), ER, and PR. Five patients did not complete the 2-week treatment period due to adverse events. All adverse events were grade 1 or 2 (NCIC-CTC scale). RAD001 treatment significantly decreased proliferation (geometric mean reduction 74% from baseline (p = 0.019)), particularly in HER-2 positive tumors. High Ki67 pre-treatment correlated with reduction in Ki67, an increase in apoptosis, a reduction in p-AKT (cytoplasmic) and reduction in p-mTOR following treatment. Nuclear expression of p-AKT was significantly reduced with treatment. Tumors that had a reduction in Ki67 with treatment exhibited a significant reduction in cytoplasmic p-AKT. p-S6 staining was significantly reduced independently of Ki67 (p < 0.001 for two sites of phosphorylation). RAD001 5 mg/daily is safe and tolerable in postmenopausal early breast cancer patients and inhibits the mTOR pathway and its downstream effectors, significantly reducing tumor cell proliferation. Tumors with high Ki67, high p-AKT, and HER-2 positivity may be more responsive to mTOR inhibition with RAD001. This is the first study to report results of RAD001 5 mg as a single agent in early breast cancer.

Predicting response to RAD001 treatment in post-menopausal women with ER-positive breast cancer using the breast cancer DSA™ research tool (Almac)

Abstract #2032

Background: RAD001 (everolimus) is a rapamycin derivative that inhibits mTOR and its downstream substrates and has shown promising results in Phase I trials. The aim of this study was to assess the feasibility of predicting patient response to RAD001 treatment from pre-treatment biopsies.&#x2028; Materials & Methods: 32 post-menopausal, ER-positive early breast cancer patients received 5mg RAD001 pre-operative treatment daily for 14 days prior to primary surgery. 25 patients completed the regimen, 6 patients withdrew and 1 did not start treatment. Biopsies were taken at diagnosis and at surgery from the RAD001 treated patients. Pre-treatment samples were flash frozen prior to RNA isolation. Patient response status was classified based on the % of Ki-67 positive cells determined by immunohistochemistry in the post-treatment biopsy (Macaskill et al., 2006: Breast Cancer Research & Treatment: 100: S1: S286). RNA from the pre-treatment group was analysed using the Almac Diagnostics Breast Cancer DSATM Research Tool, which represents ∼60,000 normal breast and breast cancer transcripts and Illumina Human Ref.8 chip v2 containing ∼24,500 transcripts representing well-categorised and most commonly known genes, irrespective of disease or tissue. For each array platform, modulated genes were identified using statistically robust gene selection methods. In addition, the sequence content of the two platforms was compared by probe-level analysis using BLAST.&#x2028; Results & Discussion: Preliminary assessment of the expression differences between the non-responder and responder groups using the DSA™ Research Tool demonstrated 169 up-regulated and 93 down-regulated genes. This list is comprised of genes involved in chemokine activity, cell adhesion and transport. Cross-platform content comparison demonstrated that the Illumina bead arrays represented 41% of transcripts on the DSA™ Research Tool whilst 82% of the Illumina beadarray transcripts were represented on the DSA™ Research Tool. Genes of interest identified will be validated by quantitative real time PCR and the key pathways reported.&#x2028; These datasets have enabled us to begin the identification of tumours most suited to RAD001 treatment and may be used as a guide for the generation of a gene expression classifier for predicting patient response to RAD001.&#x2028; Acknowledgements: This work was supported by a grant from Breast Cancer Research Treatment, UK.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2032.

A randomised study comparing the effects of anastrozole and letrozole on lipid metabolism

Abstract #1152

Background:&#x2028; Aromatase inhibitors (AIs) reduce circulating oestrogen which may have a detrimental effect on lipid metabolism. Letrozole (L) decreases circulating oestrogen levels to a greater degree than anastrozole (A). This study compares the effects of adjuvant anastrozole and letrozole on lipid metabolism.&#x2028; Patients and Methods:&#x2028; This was an open, randomised pharmacodynamic study. Plasma lipids were measured in a subset of 57 out of 182 postmenopausal women with invasive ER positive breast cancer. As part of their adjuvant hormone therapy, patients were randomized to receive either&#x2028; · 12 weeks of L followed by 12 weeks of A (L→A) or&#x2028; · 12 weeks of A followed by 12 weeks of L (A→L).&#x2028; Fasting blood and urine samples were collected at the same time of day and the same day at entry and after 12 weeks of each drug.&#x2028; · 29 had no prior tamoxifen and&#x2028; · 27 had received tamoxifen.&#x2028; The following lipoproteins were measured:&#x2028; - Triglyceride - HDL&#x2028; - Cholesterol - ApoA1&#x2028; - ApoB&#x2028; - Cholesterol&#x2028; - cLDL&#x2028; HDL and ApoA1 are cardioprotective whereas ↑ levels of the others are associated with an ↑ risk of coronary artery disease.&#x2028; Results:&#x2028; (Expressed as absolute changes +/- 95% CI)&#x2028; Patients who stopped tamoxifen &gt;12 weeks prior to trial entry were considered tamoxifen free. Patients who had stopped tamoxifen &lt;12 weeks prior to trial entry were considered to have tamoxifen in their system at trial entry.&#x2028; A vs L: &#x2028; There were no significant differences detected between A and L.&#x2028; A vs L in tamoxifen vs no tamoxifen groups:&#x2028; Triglycerides. Both A and L resulted in a significant decrease in triglycerides in patients who had tamoxifen in their systems, A = -0.02 (-0.24, 0.20) and L = 0.08 (-0.13, 0.29) vs those with no prior tamoxifen A = 0.51 (0.35, 0.68) and L = 0.56 (0.39, 0.72). A p = 0.0003 and L p = 0.001 respectively.&#x2028; ApoB. Both A and L resulted in a significant decrease in ApoB in patients who had tamoxifen in their systems, A = 0.78 (0.64, 0.91) and L = 0.84 (0.71, 0.97) vs those with no prior tamoxifen A = 0.92 (0.82, 1.02) and L = 0.91 (0.80, 1.01). p = 0.03 for both drugs.&#x2028; HDL. A resulted in a significant increase in HDL in patients who had tamoxifen in their systems 1.68 (1.49, 1.86) vs those with no prior tamoxifen 1.38 (1.24, 1.53) p = 0.02.&#x2028; There were no significant changes for any other variables measured.&#x2028; Conclusions:&#x2028; There were no significant differences between letrozole and anastrozole in their effects on lipids.&#x2028; Patients who had recently completed tamoxifen and commenced anastrozole or letrozole showed beneficial changes in their lipid profile compared to patients with no tamoxifen in their systems.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1152.

A randomised study comparing the effects of anastrozole (A), letrozole (L), exemestane (E) and tamoxifen (T) on coagulation

Abstract #1132

Background:&#x2028; Aromatase inhibitors (AIs) reduce circulating oestrogens and so should have either no or a positive effect on coagulation . This study compares the effects of the non-steroidal aromatase inhibitors, A and L and the steroidal inactivator, E on coagulation.&#x2028; Patients and Methods:&#x2028; This was an open, randomized pharmacodynamic study. Plasma coagulation factors were measured in 120 postmenopausal women with invasive ER +ve breast cancer. As part of their adjuvant hormone therapy, patients were randomized to receive upfront therapy with either:&#x2028; 16 weeks of A, 16 weeks of L or 16 weeks of E.&#x2028; Fasting blood samples were collected at entry and after 12 and 16 weeks of each drug. AI patients were then switched to T and further samples measured after 8 months on T.&#x2028; Plasminogen activator inhibitor (PAI) antigen, von Willebrand's Factor (vWF) antigen, antithrombin III (AT111), protein C, protein S total, protein S free, activated protein C, resistance (APCR), factor VIII and fibrinogen were measured.&#x2028; Results:&#x2028; Results expressed as % change from baseline.&#x2028; E vs A vs L&#x2028; Protein C. E caused a significant fall compared to A and L (-15.75 (-21.48, -10.02) vs -3.80 (-10.77, 3.16) vs -3.63 (-10.50, 3.25)) respectively. p = 0.008.&#x2028; ATIII. E caused a significant fall from baseline (-8.55 (-13.33, -3.79))&#x2028; Protein S Free. E + A caused a significant increase from baseline (E 6.90 (1.98, 11.82), A 7.36 (1.37, 13.34).&#x2028; Steroidal vs non-steroidal:&#x2028; Protein C. A significantly greater fall was seen with E than A+L (-15.75 (-21.45, -10.05) vs -3.71 (-8.58, 1.15)) p = 0.002.&#x2028; vWF A+L caused a significant increase from baseline (6.52 (0.66, 12.38) but this was not statistically different to E 5.02 (-1.88, 11.91)).&#x2028; ATIII A significant decrease from baseline was seen with A + L, -4.54 (-8.64, -0.43) but no difference from E 8.55 (13.31, -3.70) p=0.21.&#x2028; Protein S Free There was a significant increase from baseline in both groups (A+L: 5.70 (1.47, 9.92), E: 6.90 (1.98, 11.81), but no difference between the groups p=0.72.&#x2028; T effect:&#x2028; AT111 and protein C levels fell significantly on T whereas protein S free increased on T. Prior A, E or L had no significant impact on post-tamoxifen results.&#x2028; Conclusions:&#x2028; No significant differences in any coagulation factors were seen between A and L&#x2028; E caused a significant fall in protein C and ATIII.&#x2028; The non-steroidal AIs caused a significant increase in vWF.&#x2028; T caused a significant fall in protein C and ATIII and a significant increase in protein S free.&#x2028; No AI significantly influenced post-tamoxifen results.&#x2028; These drugs have significant effects on coagulation which helps to explain their clinical effects on thrombotic and thromboembolic disease.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1132.

Endovascular Treatment of Common Iliac Occlusion in the Presence of Persistent Sciatic Artery

Persistent sciatic artery is a rare congenital anomaly. It is associated with increased incidence of aneurysmal dilatation, thrombosis, distal embolization, and atherosclerotic change. We describe the case of a patient with persistent sciatic artery who presented with a critically ischemic left leg as a result of an occluded left common iliac artery, which was treated by angioplasty and stenting, and discuss the endovascular iliac recanalization in the presence of a persistent sciatic artery.

Letrozole suppresses plasma oestradiol (E2) levels more completely than anastrozole in postmenopausal women with breast cancer

552

Background: Letrozole (L) is a more potent aromatase inhibitor in vitro than anastrozole (A). One study in 12 patients showed that in patients L provides more complete inhibition of whole body aromatase and suppression of estrone sulphate levels than A but L did not significantly suppress E2 levels more than A possibly because of the small size of the study and the difficulty of measuring E2 in postmenopausal women (Geisler et al, JCO, 20, 751, 2002). The current aim was to conduct a much larger study to determine whether 2.5mg L suppresses E2 significantly more than 1mg A and if so in what proportion of patients this is the case. Methods: 54 postmenopausal women with invasive estrogen receptor positive breast cancer were randomised as part of their adjuvant hormone therapy to receive either: 12 weeks of L followed by 12 weeks of A (L→A) or 12 weeks of A followed by 12 weeks of L (A→L). Blood for hormones were taken at the same time of the day before and after 12 weeks of each drug. E2 was measured by a highly sensitive radioimmunoassay (Dowsett et al, Cancer Res 1987;47:1957–61) with a formal detection limit of 3pmol/l. In this study we also quantified values by extrapolation below this limit. Results: 27 patients had L→A and 27 A→L. Baseline E2 levels varied from 3 to 91 pmol/l with a median of 26 pmol/l. Only 1of 54 (2%) patients had an E2 value ≥ 3pmol/l after L compared with 20 of 54 (37%) after A(p <0.000005). After extrapolation, mean E2 level after A was 2.91 (SEM 0.18) pmol/l with a median of 2.70 pmol/l and after L was 1.76 (SEM 0.10) pmol/l with a median of 1.70 pmol/l (p<0.0001). Mean residual estradiol was 9.2% of baseline with A and 5.6% with L. Conclusions: This study has demonstrated unequivocally that the more complete inhibition of aromatase achieved by 2.5mg of letrozole than 1mg of anastrozole results in a greater degree of suppression of E2, the most bioactive oestrogen.

[Table: see text]

Surgeons’ views on multi-disciplinary breast meetings

The aim of this study was to assess surgeons' views and their current commitments to multi-disciplinary breast meetings (MDMs). Two hundred and fifty questionnaires were sent out to registered members of the British Association of Surgical Oncology. Hundred and fifty-three were returned (reply rate 61.2%), of which 136 were suitable for analysis. All those who replied were involved in MDMs. 80.9% held MDMs once a week. Only 28% of MDMs were held during a protected session. Over 95% of surgeons and breast care nurses were present for the whole meeting. Radiologists and pathologists were present for the whole meeting in 90-95% of cases. In contrast, clinical oncologists were present for the whole MDM in 70% of cases and medical oncologists attended the whole meeting in only 44.1% of cases. There was variability in which patients were discussed in MDMs, and in many centres not all patients with cancer were discussed before surgery. Suggestions for improvement of MDMs included more time on protected sessions (72.8% in favour), time to prepare for meetings (29% in favour), allocation of a designated co-ordinator (30.9% in favour) and attendance of oncologists for the whole meeting (over 35% in favour). The majority of Breast MDMs were held at breakfast, lunch or the evening. There was variable attendance with a significant percentage of both clinical and medical oncologists not being present for the whole meeting. A quarter of units did not discuss patients with breast cancer before operation. This study shows that there is a need to improve provision for MDMs and to produce guidelines for these meetings.