Abstract P6-09-39: The role of quantitative estrogen receptor status in predicting breast tumor response to neoadjuvant chemotherapy

Introduction:

Patients with Estrogen Receptor negative breast cancer (BC) are known to have higher tumor response rates than ER positive patients when treated with neoadjuvant chemotherapy (NCT). Few studies have assessed ER status as a quantitative continuous measure in predicting tumor response in this setting.

We aimed to study the association between quantitative ER status and tumor response at surgery in BC patients treated with NCT at our institution, and identify potential predictors of better survival outcomes.

Methods:

A retrospective review using a neoadjuvant BC database (The "Sunnybrook Biomatrix") identified 304 eligible patients that were included in the analyses. A univariate followed by a multivariable logistic regression analyses were conducted to assess the association between quantitative ER (expressed in percentage) and tumor response (good vs. poor response defined as < vs. ≥ 50% reduction in tumor size) while controlling for potential confounders.

For the secondary outcome, the Kaplan Meier method was used to estimate the recurrence free survival (RFS) in this cohort. Predictors of RFS were identified using a cox proportional hazards model (CPH) to adjust for clinically relevant variables. A log-rank test was used to compare RFS between groups for any significant binary predictor.

Results:

The median follow up of all patients was 43.3 months (Q1-Q3: 28.7-61.1). Quantitative ER was inversely associated with tumor response in a multivariable logistic regression model (Odds Ratio 0.99 95%CI: 0.99-1.00, p=0.027). A cut-off of 60% seemed to best predict the association based on the c-statistic (c=0.67) and the receiver operating characteristic curve.

However, quantitative ER was not associated with RFS; pathologic complete response (pCR) was shown to be an independent predictor of RFS in a CPH model (Hazard Ratio: 0.17, 95% CI: 0.07, 0.43, p=0.0002) in all patients, after controlling for potential confounders. At 5 years, 93% of patients with pCR and 72% of patients with residual tumor (no pCR) were recurrent-free respectively (log-rank test p=0.0012).

Conclusion:

This study suggests that BC patients with ER status < 60% are more likely to respond to NCT. Although ER status itself did not predict for relapse-free survival, patients with a pCR had better RFS, and this association was seen amongst all tumor phenotypes.

The role of quantitative ER in predicting and maximizing tumour response to NCT (including optimizing pCR rate) needs to be better defined in prospective studies.

Key words: Estrogen receptors, breast cancer, quantitative, tumor response, pathologic complete response.

Citation Format: Raphael J, Trudeau M, Paramsothy T, Lee N, Gandhi S. The role of quantitative estrogen receptor status in predicting breast tumor response to neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-09-39.

Abstract P6-10-17: Rates of prophylactic surgeries among BRCA 1 or 2 mutation carriers: A single institution experience

Background

Women with identified BRCA1/2 mutation have a substantially increased risk of developing several types of cancer, mainly breast and ovarian, during their lifetime. Management options included close surveillance, chemoprevention and prophylactic surgeries. The aim of this study is to assess the rate of prophylactic surgeries among BRCA1/2 carriers counseled and screened at a single institution in the last 2 decades.

Methods

We retrospectively captured all women with a BRCA1/2 mutation that were identified in our genetic clinic between 2000 and 2015. The incidence of breast and ovarian cancer among all BRCA carriers was reported. The rates of prophylactic surgeries were calculated and analyzed in all identified carriers.

Results

Six hundred and eighty four women were identified to carry a deleterious BRCA mutation, among them 364 BRCA1 (53%) and 320 BRCA2 (47%). Three hundred and twenty seven (48%) were diagnosed with breast cancer and 80 (12%) had either ovarian or fallopian tumor. Forty percent (N=271) of the women assessed were healthy carriers. Prophylactic bilateral salpingo-oophorectomies (BSO) were performed in 342 women (50%) and prophylactic mastectomies (PM) (bilateral or unilateral) in 190 (28%). Furthermore, 154 women (23%) had both BSO and PM. Of note, 79 women (12%) were less than 35 years old and 122 were less than 40 years old (18%), the majority of those were waiting to have BSO later on. If we remove the young women from the analysis, 57 and 61% of the women would have had BSO (less than 35 and 40 years excluded respectively). If we only analyze the women who had a recent follow up in our clinic (2014-2015), 422 women would be eligible. Among those, 58 and 84 were less than 35 and 40 years old (y) respectively. For this cohort, the rates of BSO would be 61% (257/422)(whole cohort), 71% (excluding women less than 35y) and 76% (excluding women less than 40y).

Conclusion

A promising rate of BSO was reported in our cohort of BRCA carriers as compared to the literature. This rate was even higher (from 50 to over 70%) when we only analyzed patients with recent follow up in clinic and when we excluded young women waiting to have BSO. More efforts are needed to determine why the rates of PM are lower, for example limited breast reconstruction resources, in order to reduce the incidence of subsequent invasive breast cancer in this high-risk population.

Citation Format: Raphael J, Hewitt P, Graham T, Ott K, Mancuso T, Lorentz J, Emmerson M, Eisen A. Rates of prophylactic surgeries among BRCA 1 or 2 mutation carriers: A single institution experience. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-10-17.

Outcome of patients with pregnancy during or after breast cancer: a review of the recent literature

BACKGROUND

An increasing number of young women are delaying childbearing; hence, more are diagnosed with breast cancer (bca) before having a family. No clear recommendations are currently available for counselling such a population on the safety of carrying a pregnancy during bca or becoming pregnant after treatment for bca.

METHODS

Using a Web-based search of PubMed we reviewed the recent literature about bca and pregnancy. Our objective was to report outcomes for patients diagnosed with bca during pregnancy, comparing them with outcomes for non-pregnant women, and to evaluate prognosis in women diagnosed with and treated for bca who subsequently became pregnant.

RESULTS

"Pregnancy and bca" should be divided into two entities. Pregnancy-associated bca tends to be more aggressive and advanced in stage at diagnosis than bca in control groups; hence, it has a poorer prognosis. With respect to pregnancy after bca, there is, despite the bias in reported studies and meta-analyses, no clear evidence for a different or worse disease outcome in bca patients who become pregnant after treatment compared with those who do not.

CONCLUSIONS

Pregnancy-associated bca should be treated as aggressively as and according to the standards applicable in nonpregnant women; pregnancy after bca does not jeopardize outcome. The guidelines addressing risks connected to pregnancy and bca lack a high level of evidence for better counselling young women about pregnancy considerations and preventing unnecessary abortions. Ideally, evidence from large prospective randomized trials would set better guidelines, and yet the complexity of such studies limits their feasibility.

[Helical tomotherapy in the treatment of malignant pleural mesothelioma: The impact of low doses on pulmonary and oesophageal toxicity]

PURPOSE

To evaluate the adjuvant treatment of malignant pleural mesothelioma by helical tomotherapy and the impact of low doses on esophageal and pulmonary toxicity.

PATIENTS AND METHODS

Between June 2007 and May 2011, 29 patients diagnosed with malignant pleural mesothelioma received adjuvant radiotherapy by helical tomotherapy. The median age was 63 years (34-72). Histologically, 83 % of patients had epithelioid malignant pleural mesothelioma. Clinically, 45 % of patients were T3 and 55 % N0. Eighty six percent of the patients were treated by extrapleural pneumonectomy and 35 % received neoadjuvant chemotherapy with platinum and pemetrexed. The median dose in the pneumonectomy cavity was 50Gy at 2Gy/fraction.

RESULTS

The mean follow-up was 2.3 years after diagnosis. Overall survival at 1 and 2 years was 65 and 36 % respectively. The median survival from diagnosis was 18 months. Median lung volumes receiving 2, 5, 10, 13, 15 and 20Gy (V2, V5, V10, V13, V15 and V20) were 100, 98, 52, 36, 19 and 5 %. The median of the mean remaining lung dose was 11Gy. Two patients died of pulmonary complications, three patients had grade 3 lung toxicity, while esophageal grade 3-4 toxicity was observed in three other patients. No significant impact of clinical characteristics and dosimetric parameters were found on pulmonary toxicity, however a V10≥50 %, a V15≥15 % and mean lung dose of 10Gy or more had a tendency to be predictive of pulmonary toxicity (P<0.1). Moreover, in our analysis, the mean lung dose seems to have a significant impact on esophageal toxicity (P=0.03) as well as low doses to the controlateral lung: V5, V10 and V13 (P<0.05).

CONCLUSION

Helical tomotherapy is a promising technique in the multimodality treatment of malignant pleural mesothelioma. Low doses received by the contralateral lung appear to be the limiting factor. A dosimetric comparison with volumetric modulated arctherapy techniques would be interesting in this setting.

Using custom protein microarrays to identify autoantibody biomarkers for the early detection of breast cancer

Abstract #2003

Background: Cancer patients make antibodies to tumor-derived proteins that are potential biomarkers for early detection. To detect autoantibodies to tumor antigens in patient sera, we have adapted novel high-density custom protein microarrays (NAPPA) expressing 6,500 candidate tumor antigens for biomarker detection. These arrays are probed with sera from patients with early stage breast cancer and healthy women. Using this approach, we identified antibodies in the sera of breast cancer patients.&#x2028; Methods: 6,500 full-length human antigens were expressed using mammalian reticulocyte lysate and captured onto NAPPA protein microarrays. Protein expression (&gt;90%) was confirmed with anti-GST antibodies. Patient sera were added, and bound IgG detected with secondary antibodies. Serum samples were obtained from 103 patients with stages I-III breast cancer, and 103 age-matched control women, all undergoing routine mammography.&#x2028; Results: Using high-density protein microarrays, sera from breast cancer patients (n=53) and healthy donor sera (n=53) were screened for autoantibodies to 6,500 protein antigens. Antigens were selected for further analysis if the 95th percentile of signal of cases and controls were significantly different (p&lt;0.05) and if the number of cases with signals above the 95th percentile of controls was larger than the number expected due to random chance (p&lt;0.05). Known tumor antigens, such as p53, were detected, as well as novel antigens such as DCC1, Rab7L and USP44. In total, 768 unique antigens were selected for further analysis with an independent set of breast cancer patient (n=50) and healthy donor sera (n=50).&#x2028; Conclusions: Custom in-situ protein microarrays can be used to detect serum tumor antigen-specific antibodies and enables the rapid, simultaneous detection of immunogenic tumor antigens from patient sera. These autoantibodies are being evaluated as potential biomarkers for the early diagnosis of breast cancer.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2003.

Trends in the prevalence of adolescent births in Antigua and Barbuda over 35 years

A retrospective study was undertaken to determine trends in teenage births in Antigua and Barbuda from 1969 to 2003. Maternity Ward records were reviewed at Holberton Hospital, site of over 90% of deliveries in Antigua and Barbuda. Maternal age for all births were included. The estimated population in Antigua and Barbuda increased from 60,159 in 1969 to 69,866 in 1998, with no suspected change in age-group or gender distribution. Births to mothers 12-13, 14-15, 16-17 and 18-19 years old were analyzed separately. Yearly birth totals for the 10-year period from 1969 to 1973 and 1999 to 2003 were compared using student t test analysis. The total number of births averaged 1075 per year with no change in trend. For females aged 12 and 13 years, there was no change in births from 1969 to 1978 compared with 1994 to 2003. For females aged 14 years, there was a 54% drop; for females aged 15 years, a 59% drop; for females aged 16 years, a 53% drop; for females aged 17 years, a 51% drop; for females 18 years, a 37% drop and for females aged 19 years, a 30% drop, while births to mothers > or = 20 years increased 25%. The decrease for all teen births was 42% from 1969-1978 to 1994-2003. Teen births accounted for 29% of all births at Holberton in 1969 to 1973 but only 16% of births in 1999 to 2003. In conclusion, Antigua and Barbuda has seen a marked drop of 42% in teenage deliveries, including a 53% drop in school-aged teens from 1969 to 2003. Explanations include factors such as economic, social, educational and medical developments.

Spinal cord stimulation for relief of abdominal pain in two patients with familial Mediterranean fever

Familial Mediterranean fever is a hereditary disease characterized by recurrent attacks of fever and serosal inflammation that commonly presents as severe abdominal pain. Though colchicine remains the mainstay of treatment, a significant proportion of patients are partially responsive, unresponsive or intolerant to it. We present two such cases where spinal cord stimulation (SCS) was used to manage the paroxysmal abdominal pain associated with this disease. Abdominal visceral pain pathways and the application of SCS techniques in its management are discussed.

Isoflurane-induced myocardial preconditioning is dependent on phosphatidylinositol-3-kinase/Akt signalling

BACKGROUND

Isoflurane and other volatile anaesthetics have a cardioprotective effect and limit myocardial infarct size to the same extent as ischaemic preconditioning. Phosphatidylinositol-3-kinase (PI3K) was found to play a key role in myocardial protection by ischaemic preconditioning. The aim of the present investigation was to evaluate whether isoflurane-induced myocardial preconditioning is dependent on PI3K signalling.

METHODS

Using a model of regional myocardial ischaemia and reperfusion, New Zealand White rabbits were subjected to 40 min of regional myocardial ischaemia followed by 120 min of reperfusion. The rabbits were randomly assigned to one of the following six experimental groups: sham-operated controls (n=5); ischaemia and reperfusion controls (n=8); isoflurane preconditioning (n=8); a PI3K inhibitor, wortmannin (0.6 mg kg(-1) i.v.) + isoflurane (n=8); and wortmannin+ischaemia and reperfusion (n=8). An additional control group of sham operation+ wortmannin (n=5) was also included. Myocardial injury was assessed by measuring the serum concentration of the MB fraction of creatine kinase (CK-MB) and infarct size was assessed by 2,3,5-triphenyl tetrazolium chloride staining. Phosphorylation of Akt, a downstream target of PI3K, was assessed by western blotting.

RESULTS

Isoflurane preconditioning was seen as reduced infarct size compared with control animals: 24 (4) and 41 (5)% respectively (P<0.05). Wortmannin inhibited this cardioprotective effect with myocardial infarct size at 44 (3)% (not significant). Akt phosphorylation was increased after isoflurane preconditioning, but administration of wortmannin blocked this effect.

CONCLUSIONS

Our data demonstrate that isoflurane protects the heart against ischaemia and decreases myocardial infarction by activation of PI3K.

Isoflurane does not mimic ischaemic preconditioning in decreasing hydroxyl radical production in the rabbit

BACKGROUND

Reactive oxygen species are an important mediator in isoflurane-induced myocardial preconditioning. However, hydroxyl radicals are also released during reperfusion after regional ischaemia. The purpose of the present study was to test whether ischaemic preconditioning and isoflurane would influence the production of hydroxyl radicals during reperfusion.

METHODS

After i.v. administration of salicylate 100 mg kg(-1) and a 30 min stabilization period, New Zealand White rabbits were subjected to 40 min of regional myocardial ischaemia and 2 h of reperfusion. Ischaemic preconditioning was elicited by 5 min ischaemia followed by 10 min reperfusion (before the 40 min ischaemia). In another group, isoflurane (2.1%) was administered for 30 min, followed by 15 min washout, before the long ischaemia. Area at risk and infarct size were assessed by blue dye injection and tetrazolium chloride staining. We quantified the level of OH-mediated conversion of salicylate to its dihydrobenzoate derivatives (2,3- and 2,5-DHBAs). Normalized values of the DHBAs (ng DHBA per mg salicylate) were calculated.

RESULTS

Mean (se) infarct size was 57 (6)% of the risk area in the untreated controls. This was significantly smaller in the ischaemic preconditioning and isoflurane groups: 22 (5) and 23 (6)% respectively. At 10 min of reperfusion, ischaemic preconditioning limited the mean increase in 2,3-DHBA to 24% from baseline, compared with 81% in control and 74% in the isoflurane group. Normalized 2,5-DHBA was maximally increased by 75% in the untreated group, 4 min after reperfusion. Ischaemic preconditioning significantly inhibited this increase (24% increase from baseline, P<0.01). However, the increase observed in the isoflurane group was not different from control (71%).

CONCLUSIONS

As already known, ischaemic preconditioning and isoflurane markedly reduced infarct size. However, only ischaemic preconditioning decreased postischaemic production of hydroxyl radicals. These different effects suggest different protective mechanisms at the cellular level.