The Influence of Mode of Presentation on the Pattern of Recurrence in Early Breast Cancer (EBC)

IntroductionAn early peak in recurrence exists in women with EBC. This may be explained underlying tumour biology or a reaction to surgery. Screen detection has been shown to have a prognostic effect independent of disease stage suggesting a connection with underlying tumour biology. We aim to determine if the pattern of recurrence differs between modes of presentation.MethodsData from 3 centres in Glasgow of consecutive women aged between 50-65yrs with early stage breast cancer (EBC) diagnosed between 1995 and 2001 were examined. Recurrence was defined as invasive disease at any site. Patients were grouped by mode of presentation into screen detection and symptomatic. Kaplan Meier and time dependent Cox analysis were performed.Results1534 women were included with a median follow up of 5.5yrs. Mode of presentation was screening in 1007 (65.6%) women. At 2.5yrs cumulative recurrence was 2.5% (95% CI 1.5-3.5) in the screen detected group and 9.7% (7.2-12.2) in the symptomatic group. At five years the corresponding rates were 7.8% (6.0-9.6) vs. 19.1% (15.6-22.6). Time dependent multivariate analysis showed that the difference in the risk of recurrence between the modes of presentation was significantly different within 2.5yrs from diagnosis compared with later than 2.5yrs (p = 0.019). The hazard ratio for recurrence within 2.5 yrs was 0.59 (95% CI 0.34-1.00, p=0.05) and after 2.5yrs was 1.23 (0.84-1.80, p =0.285).ConclusionsThese results suggest that women with screen detected cancers have a better prognosis initially following diagnosis independent of disease stage. However this additional benefit isn't maintained with longer follow up.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3056.

The Influence of Oestrogen Receptor (ER) Status on the Pattern of Recurrence in Early Breast Cancer

IntroductionThere is an early peak in recurrence in women with early breast cancer (EBC). This may be related to underlying tumour biology or secondary to a reaction to surgery. We aim to determine if ER expression influences the pattern of recurrence.MethodsData from 3 centres in Glasgow of consecutive women with EBC diagnosed between 1995 and 2001 were examined. Recurrence was defined as invasive disease at any site. Patients were grouped as high ER (≥70% expression), low ER (<70% expression) and ER negative. Kaplan Meier and Time dependent Cox survival analysis was performed.Results2779 women were included with a median follow up of 5.5yrs. 1915 (68.9%) had high ER, 310 (11.2%) had low ER and 554 (19.9%) were ER negative. At 5yrs the cumulative recurrence rates were 10.4% (9.0-11.8) vs. 19.2% (14.7-23.7) vs. 30.5% (26.6-34.4) respectively. Time dependent multivariate analysis showed that low ER and ER negative were significantly stronger predictors of recurrence within 2.5yrs from diagnosis than at later intervals (p = 0.024 and p <0.001 respectively). The hazard ratios for recurrence within 2.5 yrs for low ER and ER negative groups were 2.23 (95% CI 1.41-3.54, p=0.001) and 3.68 (2.60-5.21, p <0.001). Beyond 2.5yrs the respective hazard ratios were 1.12 (0.77-1.64, p=0.558) and 1.40 (1.03-1.90, p=0.031)ConclusionsWomen with Low ER expressing and ER negative tumours are initially at a significantly increased risk of recurrence compared with women with high ER expressing tumours suggesting that underlying tumour biology contributes to the initial peak in recurrence.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6042.

Does the Additional Prognostic Benefit of Screen Detection in Early Breast Cancer Apply to All Patients?

IntroductionScreen detection may confer prognostic benefit independent of disease stage in EBC leading to suggestions that mode of presentation should be considered when deciding adjuvant therapy. We aim to determine if this additional prognostic benefit is seen in all patients.MethodsData from 3 centres in Glasgow of consecutive women aged between 50-65yrs with EBC diagnosed between 1995 and 2001 were examined. Patients were grouped by mode of presentation into screen detection and symptomatic. Breast cancer specific survival was the endpoint. Multivariate analysis including interaction between mode of presentation and pathology was performed with further subgroup analysis if the interaction was significant.Results1534 women were included with a median follow up of 5.5yrs. Mode of presentation was screening in 1007 (65.6%) women. After adjustment for pathology screen detection had no significant survival benefit: HR 0.73 (0.50-1.08, p = 0.116). Mode of presentation had an independently significant interaction with both nodal status and ER status (p = 0.003 and p = 0.01 respectively). Further analysis demonstrated that screening was an independent predictor of survival in the 1-3 node positive group (HR 0.33 (0.15-0.73), p = 0.006); the ER positive group (HR 0.53 (0.31-0.89), p = 0.017) and in the moderate NPI group only (HR 0.54 (0.31-0.94), p = 0.030).ConclusionsThese results provide evidence of a significant interaction between mode of presentation and pathology. Further research is needed before incorporating mode of presentation into decisions regarding adjuvant therapy.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4007.

The Influence of HER2 Status on the Recurrence Pattern in Oestrogen Receptor Positive (ER+) Early Breast Cancer (EBC)

IntroductionAromatase inhibtors (AI) are recommended in the adjuvant management of oestrogen receptor positive (ER+) early breast cancer (EBC). With no consensus regarding the decision between starting AIs upfront or after an initial period of tamoxifen identifying factors that predict early recurrence on tamoxifen would help guide clinicians to choose the appropriate treatment strategy. HER2 overexpression and progesterone receptor (PR) negativity are poor prognostic factors in ER+ EBC. We aim to investigate whether these factors are particularly strong predictors of early recurrence.MethodsER, PR and HER2 receptor analysis was performed on a retrospective cohort of women with symptomatic early breast cancer diagnosed between 1980 – 2002 who received adjuvant tamoxifen. The primary endpoint was disease free survival (DFS) and recurrence was defined as invasive disease at any site as determined by histopathology or a high index of suspicion upon radiological investigation. Univariate and multivariate time dependent Cox regression analysis, using ≤2.5yrs as the time dependent term, were performed. The pattern of recurrence over the first five years was charted using an Epanechnikov smoothing function.ResultsA total of 402 tumours were confirmed as ER+ and therefore included in the analysis. The median age of the cohort was 63yrs with a median follow up of 6.1yrs. 241 (60.0%) of the tumours were PR+ and 51 (12.7%) were HER2 positive. On univariate analysis tumour size, grade, nodal status and PR status were significantly associated with DFS (p <0.001; except PR status, p = 0.002). In univariate time dependent analysis only HER2 status had a significant interaction with the time dependent term (p = 0.004) with a hazard ratio (HR) of 2.78 (95% CI 1.47-5.26) for DFS within the first 2.5yrs following diagnosis and a HR of 0.48 (0.18-1.34) beyond 2.5yrs. Following adjustment for pathology and PR status this interaction remained significant (p = 0.004; <2.5yrs HR 2.54 (1.21-5.32); >2.5yrs HR 0.33 (0.10-1.11)). Fig 1. clearly demonstrates a peak in the annual recurrence rate at 2yrs in the HER2 positive group.ConclusionsThis data shows that HER2 positive patients are at a significantly higher risk of recurrence within the first 2.5yrs following diagnosis of ER+ EBC. Whilst TransATAC and BIG 1-98 subgroup analysis demonstrate that HER2 is not predictive for response to AIs over tamoxifen, HER2 positive patients did show a significant reduction in recurrence on an AI in line with the remainder of the cohorts. We would therefore suggest that delaying initiation of AI therapy potentially leaves women at greater risk of early recurrence. Perhaps more importantly we should ensure that all ER positive HER2 positive patients receive trastuzumab along with their endocrine therapy as there is now significant in vitro and clinical evidence that inhibition of growth factor pathways is essential for endocrine sensitivity.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4045.

IHC for Her2 with CBE356 antibody is a more accurate predictor of Her2 gene amplification by FISH than HercepTest in breast carcinoma

BACKGROUND

Her2 (c-erbB-2/neu) overexpression in breast carcinoma predicts response to the anti-Her2 monoclonal antibody, trastuzumab, and is associated with a poor prognosis. When considering patients for trastuzumab treatment, Her2 protein expression is measured by imunohistochemistry (IHC) and, where staining is equivocal, by fluorescence in situ hybridisation (FISH) detection of Her2 gene amplification.

AIMS

To compare IHC using CBE356 with IHC using the Food and Drug Administration approved HercepTesttrade mark.

METHODS

CBE356 and HercepTest were analysed using 167 FISH characterised breast carcinomas. Immunohistochemical expression of Her2 was measured semiquantitatively. Sensitivity, specificity, predictive values, and overall accuracy were calculated for both IHC methods using gene amplification by FISH as the end point, and IHC and FISH assays were tested in Kaplan-Meier survival analysis.

RESULTS

The accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of CBE356 positive (2+ and 3+) cases were 94%, 89%, 95%, 84%, and 97%, respectively, and of HercepTest positive (2+ and 3+) cases were 91%, 66%, 98%, 92%, and 91%, respectively. A positive result with CBE356, HercepTest, or FISH was associated with significantly decreased overall survival (log rank p = 0.005, p = 0.0017, and p = 0.0005, respectively).

CONCLUSIONS

Positive IHC staining for Her2 using CBE356 is 3% more accurate and 23% more sensitive at predicting Her2 gene amplification by FISH than positive staining with HercepTest. Negative IHC using CBE356 antibody is 6% more likely to represent a truly negative result than negative staining with HercepTest. Overall, CBE356 was a more accurate predictor of Her2 gene amplification by FISH than HercepTest.

Activity of doxorubicin covalently bound to a novel human serum albumin microcapsule

Doxorubicin is widely used in the treatment of human malignancies, however is associated with significant cardiac, bone marrow and gastro-intestinal toxicity. Delivery systems may ameliorate this toxicity and increase treatment specificity by increasing the proportion of drug delivered to sites of disease. We have developed a novel preparation of doxorubicin (Dox) covalently linked to a heat stabilised human serum albumin microparticle (HSAM) carrier (median particle diameter of 4 microm) and assessed its activity in 4 malignant cell lines.

MATERIALS AND METHODS

Doxorubicin microcapsules were compared with free doxorubicin in the rat carcinoma cell line, WRC256, and the human lines, OVCAR3, MCF7 and the Dox resistant MCF7/Dox, using a cell counting technique. IC50 were calculated from regression analysis of the resulting survival curves. Endocytosis of the microcapsules by cells in culture was observed. The rate of microcapsule uptake was assessed using dual wavelength filtered fluorescence microscopy and flow cytometry.

RESULTS

The mean IC50 following incubation with the Dox microcapsules was around 5 times greater than Dox for WRC256 (p < 0.001), MCF7 (p < 0.01) and for OVCAR3 (p < 0.01). MCF7/Dox was significantly more sensitive to Dox microcapsules than free Dox (p = 0.034). A negative correlation between the rate of microcapsule uptake and the IC50 values for each cell line in culture exists (r = -0.96, p = 0.04).

CONCLUSIONS

We conclude that: 1) Doxorubicin microcapsules retain activity in vitro and appear to overcome p-glycoprotein mediated Dox resistance. 2) The observed activity of Dox microcapsules correlates with the rate of particle uptake. Further studies in animal tumour models are in progress.

Radiotracer measurement of ureteric blood flow

This paper describes a novel technique using the blood flow tracer C14-iodoantipyrine to measure ureteric blood flow in anesthetized Sprague-Dawley rats. The ureters were divided into five equal segments, and the blood flow was measured using a modification of the Fick principle. There was a gradient down the ureter with a significant difference between upper (159 ml./100 gm./min.) and lower (83 ml./100 gm./min.) ureteric segmental blood flows. This technique may allow the role of ureteric ischemia to be investigated in a variety of disease states.

Gastric and duodenal mucosal blood flow in patients receiving non-steroidal anti-inflammatory drugs--influence of age, smoking, ulceration and Helicobacter pylori

Using laser Doppler flowmetry, we measured gastric and duodenal mucosal blood flow in 70 patients who had taken non-steroidal anti-inflammatory drugs (NSAIDs) for longer than 4 weeks, and studied the correlation with demographic factors, ulceration, and Helicobacter pylori. Blood flow was also measured in 17 other subjects not taking any drugs. Measurements were taken from healthy-looking mucosa in the gastric antrum and the first part of the duodenum. Both gastric and duodenal blood flow values were significantly lower in patients taking NSAID than in those who did not. In the NSAID group, the median duodenal mucosal blood flow was 150 perfusion units in smokers (n = 29) compared with 175 in non-smokers (P = 0.024), 123 units in patients with duodenal ulcers (n = 12) compared with 160 in those without duodenal ulcers (P = 0.020), 135 units in patients with H. pylori (n = 30) compared with 168 in patients without H. pylori (P = 0.033), and 118 in smokers infected with H. pylori compared with 175 units in non-smokers not infected with H. pylori (F = 13.4, P = 0.0005). There was no correlation with age. Gastric blood flow was not significantly influenced by any of the above variables. These results suggest that chronic NSAID intake is associated with reduced blood flow in both the stomach and duodenum. However, amongst NSAID patients, duodenal, but not gastric, mucosal blood flow is reduced in smokers, and in those with duodenal ulcers and H. pylori.(ABSTRACT TRUNCATED AT 250 WORDS)

The combination of degradable starch microspheres and angiotensin II in the manipulation of drug delivery in an animal model of colorectal metastasis

Both biodegradable emboli and pharmacological agents can enhance regional therapy for hepatic targeting. Using a rat model with similar haemodynamic characteristics to human colorectal liver tumour and a radio-labelled marker of similar molecular weight to Adriamycin, we have combined the two approaches to see if the effect was addictive. Following induction of liver tumour in male hooded rats by intrahepatic injection of HSN sarcoma cells, the relative distribution of marker, 99mTc methylene diphosphonate (MDP), was studied in three groups given the following by injection into the hepatic artery. (1) Saline (Control) + MDP; (2) Degradable Starch Microspheres (DSM) + MDP; and (3) Angiotensin II + DSM + MDP. Both Degradable Starch Microspheres alone (P less than 0.001) and Degradable Starch Microspheres + Angiotensin II (P = 0.003) significantly increased the retention of marker in liver and tumour at 1 min following injection, with a 12-fold improvement over controls, but the tumour:liver ratio was unaltered. By 90 min the MDP levels in normal hepatic parenchyma had returned to control values. There was relatively less washout with significant retention in tumour tissue in both DSM (P = 0.03) and combination treated animals (P = 0.001), with a significantly improved (P = 0.001) tumour to liver ratio (5.22:1) in combination treated animal relative to those treated with DSM alone.

The distribution of alternative agents for targeted radiotherapy within human neuroblastoma spheroids

This study aims to select the radiopharmaceutical vehicle for targeted radiotherapy of neuroblastoma which is most likely to penetrate readily the centre of micrometastases in vivo. The human neuroblastoma cell line NB1-G, grown as multicellular spheroids, provided an in vitro model for micrometastases. The radiopharmaceuticals studied were the catecholamine analogue metaiodobenzyl guanidine (mIBG), a specific neuroectodermal monoclonal antibody (UJ13A) and beta nerve growth factor (beta NGF). Following incubation of each drug with neuroblastoma spheroids, autoradiographs of frozen sections were prepared to demonstrate their relative distributions. mIBG and beta NGF were found to penetrate the centre of spheroids readily although the concentration of mIBG greatly exceeded that of beta NGF. In contrast, UJ13A was only bound peripherally. We conclude that mIBG is the best available vehicle for targeted radiotherapy of neuroblastoma cells with active uptake mechanisms for catecholamines. It is suggested that radionuclides with a shorter range of emissions than 131I may be conjugated to benzyl guanidine to constitute more effective targeting agents with potentially less toxicity to adjacent normal tissues.

Failure of Doppler ankle pressure to predict healing of conservative forefoot amputations

Fifty minor foot and transmetatarsal amputations were studied to assess the reliability of Doppler ankle blood pressure (DABP) and skin blood flow (SBF) to predict healing. The level of amputation was determined solely on clinical criteria. Thirty-six (72 per cent) of the amputations healed. There was no statistical difference between mean DABP in healed 89 +/- 8 mmHg mean +/- s.e.m.) and non-healed (91 +/- 12 mmHg mean +/- s.e.m.) amputations. SBF was assessed by 125I-iodoantipyrine clearance in 28 patients. There was no correlation between DABP and SBF (r = 0.038). SBF in patients with healed amputations was 14.8 +/- 1.2 (mean +/- s.e.m.) ml 100 g-1 min-1 in contrast to SBF of 5.9 +/- 0.3 (mean +/- s.e.m.) ml 100 g-1 min-1 in the patients with non-healing (P less than 0.01). Where the flow was in excess of 8 ml 100 g-1 min-1 healing was always obtained while a flow of less than 7 ml 100 g-1 min-1 was associated with healing failure. These results suggest that DABP should be interpreted with caution as this technique fails as an accurate means of identifying those patients suitable for forefoot amputations. Skin blood flow assessment appears to provide an absolute value for the prediction of healing potential at this level.