Systematic development and feasibility testing of a multibehavioural digital prehabilitation intervention for patients approaching major surgery (iPREPWELL): A study protocol

Improving outcomes for people undergoing major surgery, specifically reducing perioperative morbidity and mortality remains a global health challenge. Prehabilitation involves the active preparation of patients prior to surgery, including support to tackle risk behaviours that mediate and undermine physical and mental health and wellbeing. The majority of prehabilitation interventions are delivered in person, however many patients express a preference for remotely-delivered interventions that provide them with tailored support and the flexibility. Digital prehabilitation interventions offer scalability and have the potential to benefit perioperative healthcare systems, however there is a lack of robustly developed and evaluated digital programmes for use in routine clinical care. We aim to systematically develop and test the feasibility of an evidence and theory-informed multibehavioural digital prehabilitation intervention 'iPREPWELL' designed to prepare patients for major surgery. The intervention will be developed with reference to the Behaviour Change Wheel, COM-B model, and the Theoretical Domains Framework. Codesign methodology will be used to develop a patient intervention and accompanying training intervention for healthcare professionals. Training will be designed to enable healthcare professionals to promote, support and facilitate delivery of the intervention as part of routine clinical care. Patients preparing for major surgery and healthcare professionals involved with their clinical care from two UK National Health Service centres will be recruited to stage 1 (systematic development) and stage 2 (feasibility testing of the intervention). Participants recruited at stage 1 will be asked to complete a COM-B questionnaire and to take part in a qualitative interview study and co-design workshops. Participants recruited at stage 2 (up to twenty healthcare professionals and forty participants) will be asked to take part in a single group intervention study where the primary outcomes will include feasibility, acceptability, and fidelity of intervention delivery, receipt, and enactment. Healthcare professionals will be trained to promote and support use of the intervention by patients, and the training intervention will be evaluated qualitatively and quantitatively. The multifaceted and systematically developed intervention will be the first of its kind and will provide a foundation for further refinement prior to formal efficacy testing.

False Positive Tumor Markers: Elevation in Patients with Breast Cancer on FAC-type Chemotherapy and Correlation with the Development of Hand-foot Syndrome

Breast cancer patients on dose-intensive chemotherapy often have elevated tumor markers during the course of treatment. Our objective was to estimate the incidence of a “false positive” tumor marker screen and to determine whether hand-foot epithelial damage was correlated.

Data from 53 patients with high risk primary breast cancer who had undergone adjuvant or neoadjuvant 5FU-containing chemotherapy (FAC or FAC plus G-CSF) for 3 to 12 months were reviewed. The relationship between tumor marker elevation and disease recur- rence, regimen intensity, and the occurrence of hand-foot syndrome was examined.

Thirty-three of the 53 patients had elevated tumor markers in the absence of recurrent disease. The false positive rate was higher in patients who underwent FAC plus G-CSF chemotherapy than in patients who underwent FAC chemotherapy (92% vs 55%, p = .01). A false positive marker screen was associated with the occurrence of hand-foot syndrome even when the effect of regimen was accounted for by stratification (p=.01).

Tumor marker screening of breast cancer patients on this type of adjuvant chemotherapy has poor specificity for recurrent malignancy. These data suggest tumor marker elevation may be an indicator of epithelial toxicity during chemotherapy, manifested clinically as hand-foot syndrome.

Abstract PD5-07: A phase III randomized trial of anastrozole and fulvestrant versus anastrozole or sequential anastrozole and fulvestrant as first-line therapy for postmenopausal women with metastatic breast cancer: Final survival outcomes of SWOG S0226

Background: Anastrozole depletes estrogen via aromatase inhibition and fulvestrant binds and degrades estrogen receptor. In a Phase III trial we compared the concurrent use of these agents to anastrozole alone or sequential anastrozole and fulvestrant in first-line therapy of hormone receptor-positive metastatic breast cancer in postmenopausal women, and demonstrated improved progression-free (PFS) and overall survival (OS)-NEJM 2012. Now we report PFS and OS five years after the initial positive findings. Methods: A total of 707 patients were randomized to either 1 mg anastrozole P.O. daily (Arm 1) or to the combination of anastrozole and fulvestrant (Arm 2). Fulvestrant was administered as a loading dose of 500 mg on day 1, 250 mg on days 14, 28 and monthly thereafter. Randomization was stratified by adjuvant tamoxifen use. The primary endpoint was PFS with OS a secondary outcome. 40% patients not in visceral crisis crossed over to fulvestrant after progression on arm 1. Analysis of survival was by 2-sided stratified log-rank tests and Cox regression using intent-to-treat. Subset analyses include treatment effect by adjuvant tamoxifen exposure, initial sites of metastases and time from diagnosis. Results: There were 646 PFS events (328 and 318 for arms 1 and 2, respectively) among 694 eligible patients (345 and 349, respectively). Overall, median PFS was 13.5 months for arm 1 and 15.0 months for the arm 2 (log-rank p=0.007; HR=0.81 (95% CI 0.69-0.94)). This benefit extended similarly in visceral and non-visceral subgroups. In subset analysis for Arms 1 and 2, respectively, in tamoxifen-naive women (60%, n=414), median PFS was 12.7 vs. 16.7 months (log-rank p=0.002; HR=0.73 (95% CI 0.60-0.89) while in women exposed to tamoxifen, median PFS was 13.9 vs. 13.6 months (log-rank p=0.57; HR=0.93 (95% CI 0.73-1.19)). An improved OS in the combination arm was seen, median OS 42 and 50 months in arms 1 and 2, based on 261 and 247 deaths, respectively (log-rank p=0.028; HR=0.82 (95% CI 0.69-0.98)). In subset analysis in tamoxifen-naive women, median OS was 40.3 vs. 52.2 months for Arms 1 and 2, respectively (log-rank p=0.007; HR=0.73 (95% CI 0.58-0.92)) while in women exposed to tamoxifen, median OS was 43.5 vs. 48.2 months (log-rank p=0.85; HR=0.97 (95% CI 0.74-1.27). Patients with initial diagnosis >10 years benefitted most from the combination (HR=0.66 (95% CI 0.49-0.89)) regardless of tamoxifen exposure. Patients in Arm 1 who crossed over had post-progression survival similar to post-progression survival of Arm 2 patients. Conclusion: The addition of fulvestrant to anastrozole was associated with improved long-term PFS and OS compared to anastrozole alone, despite the use of fulvestrant at a dose lower than the approved, and despite the substantial cross over to fulvestrant after progression on anastrozole alone. The benefit was especially notable in those without recent exposure to adjuvant endocrine therapy. Ongoing translational medicine studies will further refine the need for up front fulvestrant. ClinicalTrials.gov:NCT00075764. Funding: NIH/NCI U10CA180888, U10CA180819 and AstraZeneca.

Citation Format: Mehta RS, Barlow WE, Albain KS, Vandenberg TA, Dakhil SR, Tirumali NL, Lew DL, Hayes DF, Gralow JR, Linden HM, Livingston RB, Hortobagyi GN. A phase III randomized trial of anastrozole and fulvestrant versus anastrozole or sequential anastrozole and fulvestrant as first-line therapy for postmenopausal women with metastatic breast cancer: Final survival outcomes of SWOG S0226 [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD5-07.

Abstract PD7-07: Discovery of molecular predictors of late breast cancer specific events (BCSE) in ER+, node+ breast cancer – new transcriptome expression whole gene analysis of the phase III adjuvant trial SWOG S8814

BACKGROUND: Unique genes and pathways were identified for prognosis on tamoxifen (T, 5 yrs) and prediction on CAF-T vs T in S8814 using whole transcriptome RNA-Seq from archival FFPE tissue. (Albain, et al; Cherbavaz, et al; SABCS 2015) Discovery was robust for early DFS events but sparse for late. The aims of this new analysis were to 1) utilize a new endpoint BCSE for gene discovery of late events, prognosis and prediction and 2) add intronic counts to the previous exonic results to define whole genes impacting on late BCSE.

METHODS: Charts of patients (pts) on CAF-T (212) vs T (142) were reviewed to define the BCSE endpoint (local/regional, contralateral, distant). Deaths without BC were treated as competing risks. BCSE models (including metagenes) of late prognosis and prediction used cumulative incidence functions. Consolidated intronic regions counts within genes were added to exonic regions counts. Using these “whole gene” (WG) counts, association of gene expression with time to BCSE was assessed by Cox regression. A multiple WG score (MWGS) for BCSE prognosis beyond 5 yrs (to 12.5 yrs) was constructed and evaluated for 1-3 and 4+ node (N) groups. False discovery rate was controlled at 10%.

RESULTS: More exons and WG were discovered for prognosis on T alone over 12.5 yrs with the BCSE endpoint than DFS. For prognosis of late BCSE after 5 yrs, more genes were discovered using WG (n=111) than by exons (n=9). There were significantly fewer genes for late BCSE on CAF-T (8, WG; 0, exons). The functions of WG prognostic for late BCSE were: cell cycle/proliferation-26 genes, chromosome segregation/mitotic spindle-22, DNA repair/maintenance-10, transcriptional/translational control-5, cell adhesion/migration-4, immune-3, diverse/unknown-32 and growth factor/hormone receptor signaling-9 (this group was only found by WGs, not exons). Of these 111 WG, a MWGS prognostic for late BCSE on T used 57 previously discovered genes pre-specified for this analysis. Probability of BCSE beyond 5 yrs for low vs high MWGS was 8% vs 21% in N1-3+ and 17% vs 42% in N4+. Late prognosis on T differed by low vs high risk defined in a metagene model: cumulative BCSE at year 10 was 0% vs 47% (low vs high risk, p=0.001). Prediction of 10-yr incidence of BCSE varied by risk level by treatment in a metagene model: low risk- CAF-T=47%, T=0% (p=0.045); high risk- CAF-T=35%, T=45% (p=0.027).

CONCLUSIONS: Gene discovery for prognosis of late BCSE is enhanced with a novel WG transcriptome expression approach. Use of chemotherapy (CT) before T significantly attenuated gene discovery, so that molecular tools for decisions on extending endocrine therapy (ET) may not be reliable in a setting of prior CT. Some pts on ET for 5 yrs may not require either longer ET or CT, given a N+ cohort was defined with no BCSE observed over 12.5 yrs. For prediction of CT benefit, CAF-T appeared to be inferior to T in a low risk metagene model for BCSE. In sum, these results add more evidence that ET alone may be sufficient (perhaps better) in select N+ settings. Validation in SWOG S1007 (RxPONDER) is planned.

SUPPORT: NCI CA180888, 180819, 180821, 180820, 180863; in part, Genomic Health, Inc.

Citation Format: Albain KS, Crager MR, Barlow WE, Baehner FL, Bergamaschi A, Rae JM, Ravdin PM, Tripathy D, Gralow JR, Livingston RB, Osborne CK, Ingle JN, Pritchard KI, Davidson NE, Carey LA, Cherbavaz DB, Sing AP, Shak S, Hortobagyi GN, Hayes DF. Discovery of molecular predictors of late breast cancer specific events (BCSE) in ER+, node+ breast cancer – new transcriptome expression whole gene analysis of the phase III adjuvant trial SWOG S8814 [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 PD7-07.

SWOG S0800 (NCI CDR0000636131): addition of bevacizumab to neoadjuvant nab-paclitaxel with dose-dense doxorubicin and cyclophosphamide improves pathologic complete response (pCR) rates in inflammatory or locally advanced breast cancer

SWOG S0800, a randomized open-label Phase II clinical trial, compared the combination of weekly nab-paclitaxel and bevacizumab followed by dose-dense doxorubicin and cyclophosphamide (AC) with nab-paclitaxel followed or preceded by AC as neoadjuvant treatment for HER2-negative locally advanced breast cancer (LABC) or inflammatory breast cancer (IBC). Patients were randomly allocated (2:1:1) to three neoadjuvant chemotherapy arms: (1) nab-paclitaxel with concurrent bevacizumab followed by AC; (2) nab-paclitaxel followed by AC; or (3) AC followed by nab-paclitaxel. The primary endpoint was pathologic complete response (pCR) with stratification by disease type (non-IBC LABC vs. IBC) and hormone receptor status (positive vs. negative). Overall survival (OS), event-free survival (EFS), and toxicity were secondary endpoints. Analyses were intent-to-treat comparing bevacizumab to the combined control arms. A total of 215 patients were accrued including 11 % with IBC and 32 % with triple-negative breast cancer (TNBC). The addition of bevacizumab significantly increased the pCR rate overall (36 vs. 21 %; p = 0.019) and in TNBC (59 vs. 29 %; p = 0.014), but not in hormone receptor-positive disease (24 vs. 18 %; p = 0.41). Sequence of administration of nab-paclitaxel and AC did not affect the pCR rate. While no significant differences in OS or EFS were seen, a trend favored the addition of bevacizumab for EFS (p = 0.06) in TNBC. Overall, Grade 3-4 adverse events did not differ substantially by treatment arm. The addition of bevacizumab to nab-paclitaxel prior to dose-dense AC neoadjuvant chemotherapy significantly improved the pCR rate compared to chemotherapy alone in patients with triple-negative LABC/IBC and was accompanied by a trend for improved EFS. This suggests reconsideration of the role of bevacizumab in high-risk triple-negative locally advanced breast cancer.

Abstract S3-02: Molecular predictors of outcome on adjuvant CAF plus tamoxifen (T) vs T in postmenopausal patients (pts) with ER+, node+ breast cancer – Transcriptome expression analysis of the phase III trial SWOG-8814

BACKGROUND: In SWOG-8814A, pts with ER+ node+ breast cancer and low 21 gene recurrence scores (RS) had good prognosis and no CAF benefit, but high RS predicted longer survival from CAF followed by T (CAF-T) vs T (Albain, Lancet Oncol 2010). The aims of SWOG-8814B were to identify novel genes and networks for 1) prognosis of early and late relapse and 2) prediction of CAF benefit, using whole transcriptome expression analysis with next generation RNA sequencing (NGS).

METHODS: Stored RNA previously extracted for SWOG-8814A (T, CAF-T arms; T, 5 yrs) was analyzed for RNA/library yield (see companion abstract Cherbavaz et al. for methods). Genes were sequenced and expression of mRNA species was related to disease-free survival (DFS) using Cox proportional hazards. Discovery analyses controlled false discovery rate (FDR) at 10%. Genes were identified for prognosis on T and prediction on CAF-T vs T. Networks of genes/pathways were explored. Early (0-5 yrs) and late (5-13+ yrs) time periods were studied. Gene Ontology, Cytoscape, pathway and hierarchical clustering were used for functional gene and metagene analyses.

RESULTS: Of 367 samples, 354 (96%; 142 T, 212 CAF-T; 141 DFS events) had sufficient RNA/library yield, with 20,101 genes sequenced. For prognosis on T, there were 2327 and 568 genes discovered in early and all-yrs follow-up, with only 9 genes prognostic after 5 yrs. Prognosis analyses for residual risk after CAF-T were uninformative. Functional mapping found that genes prognostic for worse DFS were enriched for proliferation (G2M, M-phase), cellular metabolism, DNA repair, stress response and EMT; whereas, those with better DFS involved transcription regulation/repression via zinc finger proteins. Hierarchical clustering (T arm) found significant DFS prognostic metagene signatures for ER-related genes, immune response, ECM/stroma, chromatin remodeling-transcription factor activity and TGFb pathway. All varied for early vs late DFS events. For example, low ER/high stroma expression signatures correlated with high proliferation gene expression and were strongly associated with early events (standardized [st] HR 2.94, p<0.001). Late recurrence was associated with high proliferation, both individually (stHR 1.51, p=.035) and in combination with higher ER expression (stHR 1.51, p=0.09). Fifteen genes predicted CAF benefit (9 better DFS, 6 worse), or 129 genes if FDR relaxed to 20%. Cluster analysis for CAF prediction is ongoing.

CONCLUSIONS: Unique genes, clusters and pathways were identified by NGS of archival material in ER+ N+ breast cancer, including previously unreported signatures. While ER, stroma and proliferation-related signatures were associated with early prognosis, proliferation best predicted worse DFS after 5 yrs. NGS of the primary tumor is most informative for early events in pts with only 5 years of T, with few genes selecting only for late relapse. If validated, these signatures may identify pts with excellent DFS despite positive nodes for endocrine therapy alone as well as others for whom chemotherapy and/or biologics are also required

.

SUPPORT: NCI CA 180888, 180819, 180821, 180820, 180863; in part, Genomic Health, Inc.

Citation Format: Albain KS, Crager MR, Barlow WE, Baehner FL, Bergamaschi A, Rae JM, Ravdin PM, Tripathy D, Gralow JR, Livingston RB, Osborne CK, Ingle JN, Pritchard KI, Davidson NE, Carey LA, Cherbavaz DB, Sing AP, Shak S, Hortobagyi GN, Hayes DF. Molecular predictors of outcome on adjuvant CAF plus tamoxifen (T) vs T in postmenopausal patients (pts) with ER+, node+ breast cancer – Transcriptome expression analysis of the phase III trial SWOG-8814. [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 S3-02.

Abstract P3-12-12: Incidence of internal mammary node, sternum, and manubrium failure as detected by FDG-18 PET/CT

Introduction:

Elective radiotherapy to the internal mammary (IM) lymph nodes remains an ongoing subject of debate. While the incidence of occult IM involvement on extended mastectomy ranges from 15-65%, reported rates of IM failure are substantially lower (approximately 1%). Interest in this subject has resurfaced recently as randomized trials have shown a survival benefit to adjuvant regional node irradiation including the IM chain. The mechanism by which extended field radiotherapy leads to improved systemic outcomes has not been clearly demonstrated and the degree of benefit directly attributable to IM irradiation remains to be seen. We hypothesized that the IM lymphatic chain may provide a direct route for tumor cell dissemination into the the sternum or manubrium. As such, sternal metastases may be a manifestation of IM involvement rather than true hematogenous metastases. We sought to better elucidate patterns of failure by evaluating the incidence and timing of IM, sternal, or manubrial involvement identified by PET/CT imaging following diagnosis of metastatic breast cancer.

Patients and Methods:

Between 2007 and 2014, 96 patients with invasive breast cancer were found to have metastatic disease as diagnosed on FDG-18 PET/CT. Site of recurrence was scored as breast/chest wall, axilla/supraclav, IM chain, sternum/manubrium, or distant. IM or sternum/manubrium failure was scored as isolated (occurring without distant metastatic disease), synchronous (involved at initial diagnosis of distant metastatic disease), or metachronous (involved at any time after diagnosis of metastatic disease).

Results:

Isolated IM failures were observed in 3.1% of patients while isolated sternum/manubrium failures were recorded in 7.3% of patients. Isolated involvement of the sternum/manubrium or IM nodes occurred in 11.4%. The rate of synchronous IM failure was 11.4% with the rate of metachronous failure being 13.5%. The rate of synchronous sternum/manubrium failure was 17.7% with the rate of metachronous failure being 23.9%. The incidence of sternum/manubrium or IM involvement at the initial diagnosis of distant metastatic disease was 29.2% with the rate of involvement at any point increasing to 36.5%.

Conclusion:

The rate of internal mammary node failure by PET/CT at the time of metastatic diagnosis is higher than the incidence reported in previous trials. This discrepancy is likely due increased sensitivity of PET/CT and the difficulty of accurately assessing this region once patients have been found to have metastatic disease. Interestingly, sternum and manubrium were more often the first site of recurrence than the IM nodes. This could be due to a tropism of hematogenous metastases for these bones or could represent direct tumor cell dissemination from the internal mammary chain. This is of special interest as this region is incidentally included in the radiotherapy fields when targeting the IM nodes. Overall, our findings suggest that historic patterns of failure studies may underestimate the local benefit of internal mammary node radiotherapy.

Citation Format: Grow JL, Choudhary G, Kuo P, Livingston RB, Gonzalez VJ. Incidence of internal mammary node, sternum, and manubrium failure as detected by FDG-18 PET/CT. [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 P3-12-12.

Abstract P6-04-10: Clinicopathological and molecular characteristics of pleomorphic invasive lobular carcinoma of breast

Background: Pleomorphic invasive lobular carcinoma (PILC) is described as a distinct morphological variant of invasive lobular carcinoma (ILC) but its clinical behavior is not well characterized. PILCs have loss of E-cadherin similar to ILCs but have distinct morphological features like nuclear contour irregularity, a single prominent nucleolus, increased hyperchromasia and more frequent mitoses. In addition, some studies have reported that PILCs have acquired further molecular alterations such as gain of HER2/neu, amplification of c-myc and loss of p53. To the best of our knowledge there have been no studies evaluating Phosphoinositide 3 kinase/Akt/mammalian (or mechanistic) target of rapamycin (PI3K/Akt/mTOR) pathway in PILC. We hypothesize that there is increased activation of PI3K/Akt/mTOR pathway in PILC compared to ILC. Activation of the PI3k/Akt/mTOR pathway was evaluated by quantifying protein expression of phosphatase and tensin homolog (PTEN) and phosphorylated-S6 kinase1 (p-S6K1). PTEN is a negative regulator of the PI3K pathway and its loss/decreased expression (by mutation or allelic imbalance) activates downstream signaling. Loss (or decrease) of PTEN expression has been reported to be associated with PI3K pathway activation in more than 50% of ER+ breast tumors. Since PI3K pathway can be activated by other mechanisms in addition to PTEN loss, we hypothesized that evaluation of pS6K1 may predict activation of this pathway more than PTEN protein expression alone.

Methods: We conducted a retrospective translational study at the University of Arizona Cancer Center. Our Pathology database was searched to identify PILCs from 2012-2014. Two investigators reviewed the pathology reports independently and abstracted clinocopathological data. Formalin-fixed paraffin embedded (FFPE) primary PILCs were stained for PTEN and pS6K1 expression. Expression of PTEN and pS6K1 was quantified by long score methodology as low (≤ 10), moderate (11-50) or high (≥ 50) expression.

Results: We identified 19 patients with PILC. All tumors were either moderately (n=10) or poorly differentiated (n=9). Estrogen receptor (ER) was positive in all, progesterone receptor (PR) was positive in 11(52%) and HER2 was negative in all tumors. Proliferation index (Ki67) was elevated in all tumors (median 32%, range 20-70%). Lymph nodes were involved with metastatic carcinoma in 7 patients (negative in 9 and unknown in 3). The 21-gene recurrence score assay (Oncotype Dx) was performed in 10 patients and demonstrated higher scores (median 23, range 6-36) with the majority being in the intermediate or high range (8/10). Expression of PTEN and p-S6K1 was quantified on 10 FFPE tumor tissues. PTEN expression was high in all while pS6K1 was high in 8 and low in 2 tumors.

Conclusion: PILCs are a biologically distinct group of ILC. Clinicopathological characteristics suggest they would have a more clinically aggressive behavior (higher grade, high proliferative index and 21 gene recurrence score). In addition, our results indicate that PI3k/Akt/mTOR pathway in activated in majority of these tumors and that PTEN is not the key regulator of this pathway. Genomic profiling is currently underway to further analyze other causes of pathway activation.

Citation Format: Segar J, Baker AF, MacKerricher W, Nagle R, Livingston R, Clarke K, Ley M, Viscusi R, Gonzalez V, LeBeau L, Chalasani P. Clinicopathological and molecular characteristics of pleomorphic invasive lobular carcinoma of breast. [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 P6-04-10.

Abstract P4-07-07: Evaluating Rad51/geminin protein expression as an indicator of homologous recombination deficiency in breast cancer models

Background: Homologous recombination deficiency (HRD) in cancer cells can occur due to mutations (germline or sporadic), methylation or other epigenetic causes. HRD leads to a defect in the conservative, error-free DNA repair mechanism and is associated with enhanced susceptibility to DNA targeting chemotherapy. Currently functional HRD assays are not broadly available for clinical use. Many of the HRD assays used in the experimental setting require fresh frozen tissue for optimal results, or require specialized expertise to interpret the results. We evaluated an immunohistochemical (IHC) assay using formalin fixed paraffin embedded (FFPE) tissue to measure protein expression of Rad51 and geminin, a cell proliferation marker, to assess HRD in breast cancer cell line models and clinical breast cancer samples. We hypothesize that Rad51, which is involved in the later stages of HR, can serve as a functional marker of HRD.

Methods: The MCF-7 human breast cancer cell line was used as a model with intact HR. Western blotting of total cell lysates from cells grown in culture was performed to confirm HR response following treatment with DNA damaging chemotherapeutic agents, cisplatin and doxorubicin. Paclitaxel, a microtubule targeting agent, was used as a negative control. Mice with MCF-7 xenograft tumors were also treated with cisplatin, or doxorubicin at two dose levels (low and high) and various time points post treatment to assess the dose and time response to HR markers. Tumors from mice treated with paclitaxel were used as a negative control. Xenograft tumors were fixed and analyzed by IHC using an antibody specific for total Rad51 and geminin expression. DNA damage was also assessed in a portion of the tumor using a pulse gel electrophoresis assay. We also analyzed FFPE breast cancer clinical samples from patients with BRCA1 mutations for Rad51 and geminin expression.

Results: In MCF-7 grown in vitro, total Rad51 was elevated as soon as 4 hours following exposure to doxorubicin and cisplatin, but not in response to paclitaxel treatment. In xenograft tumors, baseline Rad51 and geminin expression were relatively high illustrating proficient HR in an actively proliferating tumor model. Rad51 expression increased post treatment with cisplatin and doxorubicin as early as 6hrs and peaked at 16-24hrs. Geminin expression correlated well with expression of Rad51 at baseline and in time response to treatment. Pulse gel electrophoresis in paired tumor samples confirmed DNA damage was occurring compared to vehicle control treated tumors. However, this technique did not show a strong dose or time response. Five breast tumors from patients with known BRCA1 mutations were stained for Rad51 and geminin expression. High geminin expression and low Rad51 expression was noted in the majority of these tumors.

Conclusions: An IHC assay using FFPE tissue to measure Rad51/geminin is a promising method to assess HRD in breast cancer. Further analytical and clinical validation of this approach is ongoing.

Citation Format: Chalasani P, Nagy D, Livingston RB, Weterings E, Nagle R, Singh S, Barnes M, Grogan T, Ridder R, Baker AF, Kandavel S. Evaluating Rad51/geminin protein expression as an indicator of homologous recombination deficiency in breast cancer models. [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 P4-07-07.

Abstract P3-07-64: Association between gene variants in SULT1A1 and UGT1A4 and disease outcomes in patients enrolled in SWOG S0226 and treated with anastrozole alone or in combination with fulvestrant for metastatic breast cancer

Background: Anastrozole (A) blocks estrogen production by inhibiting the activity of CYP19 aromatase. Fulvestrant (F) blocks estrogen receptor (ER) signaling by competitive binding, leading to ER degradation by ubiquitination. SWOG S0226 ("Phase III Randomized Trial of Anastrozole versus Anastrozole and Fulvestrant (250mg LD) as First Line Therapy for Post Menopausal Women with Metastatic Breast Cancer," ClinicalTrials.gov Identifier:NCT00075764) demonstrated that combination of A+F is superior to A alone as first-line therapy for patients with ER positive metastatic breast cancer (Mehta et al, NEJM, 2012). Our functional preclinical studies have shown that single nucleotide polymorphisms (SNPs) in SULT1A1 and UGT1A4, drug conjugation enzymes that inactivate A and F, result in decreased enzyme activity toward these drugs (Edavana et al, DMD, 2013; Edavana et al Pharmgenomics Pers Med 2013). We therefore hypothesized that these SNPs will be associated with disease outcomes in S0226 patients due to altered drug levels.

Methods: Germline DNA was available for 295 (43.5%) patients enrolled in S0226 overall (157 on A and 138 on A+F). SNPs in SULT1A1 and UGT1A4 were determined either by direct sequencing or allele-specific PCR (TaqMan) assays.

Results: There was no difference in progression-free survival (PFS) or overall survival (OS) comparing patients with or without available germline DNA (p = 0.86 and 0.36, respectively). The SULT1A1 G902A allele (rs6839), which confers decreased mRNA and enzymatic activity, was associated with improved PFS (GG/GA vs. AA; HR 0.74, 95% CI 0.56-0.98, p=0.033) and OS (HR 0.70, 95% 0.50-0.98, p=0.039). In exploratory subset analyses of PFS, the SULT1A1 G902A association was similar across both treatment arms (A HR=0.75; 95% CI 0.51-1.10; A+F HR=0.73; 95% CI 0.48-1.11). For OS there was some evidence of a difference by treatment (A HR=0.60; 95% CI 0.38-0.96; A+F HR=0.82; 95% CI 0.50-1.32), though no significant interaction was evident (p=0.30).

The UGT1A4 G-163A promoter variant, which leads to decreased protein expression, was not associated with PFS (AA/AG vs. GG HR 0.88, 95% CI 0.68-1.14, p=0.33); however, this variant was associated with OS (HR 0.71, 95% CI 0.52-0.96, p=0.027). In subset analyses with OS, the difference was marginally stronger in the A arm (HR 0.63, 95% CI 0.42-0.97, p=0.035) compared to the A+F arm (HR 0.77, 95% CI 0.49-1.21, p=0.25), though the interaction was not significant (p=0.40).

Conclusion: SULT1A1 and UGT1A4 gene variants resulting in decreased enzyme activity were associated with better PFS, OS or both in patients enrolled in SWOG S0226. Planned validation studies correlating these SNPs with drug levels and disease outcomes in additional patient cohorts will establish their clinical utility in identifying patients who benefit from A and F alone or in combination.

Funding: Supported by NIH/NCI CA118981; NIH/NCI/NCTN grants CA180888, CA180819, and CA180863; and in part by AstraZeneca.

Citation Format: Kadlubar SA, Barlow WE, Mehta RS, Daniels JR, Albain KS, Vandengerg TA, Dakhil SR, Tirumali NR, Lew DL, Gralow JR, Livingston RB, Hortobagiyi GN, Hayes DF, Rae JM. Association between gene variants in SULT1A1 and UGT1A4 and disease outcomes in patients enrolled in SWOG S0226 and treated with anastrozole alone or in combination with fulvestrant for metastatic breast cancer. [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 P3-07-64.

Abstract P1-03-01: Circulating CAIX as a biomarker in breast cancer

Introduction: Carbonic anhydrase-IX (CAIX) facilitates the reversible hydration of carbon dioxide to bicarbonate and protons, a process integral to maintaining pH differences across the cancer cell plasma membrane. CAIX is regulated by hypoxia inducible factor-1 alpha (HIF-1 alpha) and is essential for the elimination of acid loads generated by glycolysis. High CAIX expression is associated with poor prognosis and chemoresistance in breast cancer patients (pts) (1-3). To explore the role of CAIX as a possible biomarker for predicting breast cancer therapies, we measured plasma CAIX levels in response to various chemotherapy regimens, including anti-angiogenics, in several breast cancer clinical trials.

Methods: Circulating plasma CAIX was quantified using a commercially available enzyme-linked immunosorbent assay (ELISA) kit (R & D Systems). We evaluated the plasma stability of CAIX by quantifying levels within 1 hour as well as at 24 and 48 hours post phlebotomy in healthy controls (n = 10). We also evaluated the ideal anticoagulant for sample collection and stability of CAIX levels over time in healthy controls. For our analysis in breast cancer pts, we quantified plasma CAIX levels in two populations treated on chemotherapeutic clinical trials: 1) locally advanced breast cancer (LABC) pts treated in the neoadjuvant setting with paclitaxel in combination with sunitinib followed by anthracycline (AC) based chemotherapy (n = 63); 2) metastatic breast cancer (MBC) pts treated with systemic chemotherapy with either irinotecan + etoposide; or paclitaxel + a novel immunomodulatory agent (n = 22).

Results: In healthy control subjects, plasma levels of CAIX were stable at all time points tested (within1 hour, 24 hrs, 48 hours post phlebotomy) with no significant change on repeat testing at 6 months. Average baseline plasma CAIX levels were lowest in normal controls (20.5 pg/ml) compared to pts with LABC (34.1 pg/ml) or MBC (90.7 pg/ml) (p = <0.001). In pts with LABC, CAIX rose significantly in response to paclitaxel/sunitinib (TS) therapy (p = 0.01) but not further with anthracycline based therapy (p = 0.37). The rise in response to TS was primarily in pts with baseline levels below the median. In pts with MBC treated with cytotoxic chemotherapies (without an anti-angiogenic) CAIX levels did not change in response to therapy.

Discussion: Plasma CAIX is a robust biomarker that is stable at room temperature in plasma for at least 48hrs and over time in healthy controls. Plasma CAIX levels are elevated in pts with MBC when compared to those with LABC or normal controls. CAIX levels rise in response to anti-angiogenic therapy but not in response to cytotoxic chemotherapy. Our results suggest CAIX may be a robust and easily measured pharmacodynamic biomarker of anti-angiogenic induced hypoxia and HIF-1 alpha upregulation.

1. Potter CP and Harris AL. Br J Cancer. 89:2-7, 2003.

2. Betof AS, Rabbani ZN, Hardee ME, et al. BJ Cancer. 106:916-922, 2012.

3. Generali D, Fox Berruti A, et al. Endocrine-Related Cancer. 13:921-30, 2006.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-03-01.

Abstract P1-12-03: Primary squamous cell carcinoma of the breast

BACKGROUND: Primary squamous cell carcinoma of the breast (PSCCB) is one of the rarest forms of breast cancer, accounting for less than 0.1% of all breast cancers. PSCCB can be aggressive with no typical radiologic findings on mammogram, often leading to delays in diagnoses or missed diagnoses. Previously reported cases of PSCCB have illustrated a wide range of clinical presentations, from an abnormal mammogram with no obvious breast mass to a breast abscess. In addition, due to the rarity of this disease, no clear consensus on definitive treatment or prognosis exists.

METHODS: Using a search of our pathology database, we identified females diagnosed with PSCCB at our institution from 2007-2012. Inclusion criteria included female patients over the age of 18 years old with a primary tumor consisting of >90% malignant cells of squamous origin. Likewise, exclusion criteria included squamous cell cancer that had metastasized to the breast from elsewhere or lesions that were not independent of the overlying skin or nipple. We then performed a retrospective review to evaluate patient characteristics, presentation, tumor characteristics, treatment modalities and outcomes.

RESULTS: We identified three patients who were diagnosed with PSCCB during that timeframe. Their ages ranged from 35-65 years old, with two being post-menopausal and one pre-menopausal. Of the three, two were Caucasian and one was Hispanic. All three presented after self-palpating a breast mass. The average size of the mass seen on mammogram was 2.9 cm (range of 2.4 to 3.6 cm). Histologically, all three of the cancers were moderately to poorly differentiated. In addition, they all had a negative estrogen, progesterone, and HER2 receptor status with an elevated Ki-67. One patient was diagnosed at our institution but did not proceed to surgery and was lost to follow up. For the other two patients, one chose to undergo breast conservation with partial mastectomy and sentinel lymph node biopsy followed by whole breast radiation. The second patient proceeded with a total mastectomy and sentinel lymph node biopsy without radiation. There was no evidence of regional nodal disease in either patient at time of surgery. Furthermore, neither patient received any systemic therapy. Both patients were disease free at last follow up which was 5 and 11 months respectively.

CONCLUSION: Because PSCCB is so rare, prognosis and optimal treatment are still controversial. Most of the current literature portrays PSCCB as an aggressive cancer with a poor prognosis. This often leads to multimodality therapy consisting of mastectomy with axillary nodal clearance, adjuvant chemotherapy and radiation. In addition, locoregional and distant recurrences are common despite this aggressive treatment leading to the conclusion that PSCCB is relatively radioresistant with limited activity seen when using conventional breast cancer systemic therapies. Because treatment options can be limited, more research is needed to further elucidate the biological behavior of this rare cancer as well prognostic factors that may allow us to treat a patient more conservatively.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-12-03.

Germline genetic variants in ABCB1, ABCC1 and ALDH1A1, and risk of hematological and gastrointestinal toxicities in a SWOG Phase III trial S0221 for breast cancer

Hematological and gastrointestinal toxicities are common among patients treated with cyclophosphamide and doxorubicin for breast cancer. To examine whether single-nucleotide polymorphisms (SNPs) in key pharmacokinetic genes were associated with risk of hematological or gastrointestinal toxicity, we analyzed 78 SNPs in ABCB1, ABCC1 and ALDH1A1 in 882 breast cancer patients enrolled in the SWOG trial S0221 and treated with cyclophosphamide and doxorubicin. A two-SNP haplotype in ALDH1A1 was associated with an increased risk of grade 3 and 4 hematological toxicity (odds ratio=1.44, 95% confidence interval=1.16-1.78), which remained significant after correction for multiple comparisons. In addition, four SNPs in ABCC1 were associated with gastrointestinal toxicity. Our findings provide evidence that SNPs in pharmacokinetic genes may have an impact on the development of chemotherapy-related toxicities. This is a necessary first step toward building a clinical tool that will help assess risk of adverse outcomes before undergoing chemotherapy.

Impact of premenopausal status at breast cancer diagnosis in women entered on the placebo-controlled NCIC CTG MA17 trial of extended adjuvant letrozole

BACKGROUND

MA17 showed improved outcomes in postmenopausal women given extended letrozole (LET) after completing 5 years of adjuvant tamoxifen.

PATIENTS AND METHODS

Exploratory subgroup analyses of disease-free survival (DFS), distant DFS (DDFS), overall survival (OS), toxic effects and quality of life (QOL) in MA17 were performed based on menopausal status at breast cancer diagnosis.

RESULTS

At diagnosis, 877 women were premenopausal and 4289 were postmenopausal. Extended LET was significantly better than placebo (PLAC) in DFS for premenopausal [hazard ratio (HR) = 0.26, 95% confidence interval (CI) 0.13-0.55; P = 0.0003] and postmenopausal women (HR = 0.67; 95% CI 0.51-0.89; P = 0.006), with greater DFS benefit in those premenopausal (interaction P = 0.03). In adjusted post-unblinding analysis, those who switched from PLAC to LET improved DDFS in premenopausal (HR = 0.15; 95% CI 0.03-0.79; P = 0.02) and postmenopausal women (HR = 0.45; 95% CI 0.22-0.94; P = 0.03).

CONCLUSIONS

Extended LET after 5 years of tamoxifen was effective in pre- and postmenopausal women at diagnosis, and significantly better in those premenopausal. Women premenopausal at diagnosis should be considered for extended adjuvant therapy with LET if menopausal after completing tamoxifen.

Variants in the BRCA1/Fanconi-Anemia Repair Pathway and Taxane-Induced Neuropathy in SWOG S0221

Background: Taxane-induced peripheral neuropathy is a dose-limiting side effect that leads to suboptimal cancer treatment and diminished quality of life. The mode of taxane neurotoxicity is unclear, but may be through stabilization of microtubules and induction of spindle checkpoint, leading to cell cycle arrest at G2/M. Fanconi Anemia (FA) genes, including FANCD2, and FANCA, appear to be involved in G2/M phase checkpoint maintenance as well as spindle checkpoint in response to internal and external signals, such as taxane treatment. Thus, we hypothesized that variants in FA genes could impact severity of taxane-induced neuropathies.Methods: Using DNA extracted from blood collected from 893 breast cancer patients participating in a trial evaluating metronomic dosing of cyclophosphamide, doxorubicin and paclitaxel (S0221), we genotyped for single nucleotide polymorphisms (SNPs) that represent all of the variability across FANCA (44 SNPs) and FANCD2 (24 SNPs) in all race/ethnicity groups, as well as a panel of ancestry informative markers to control for potential population stratification, using Illumina GoldenGate platform. SNPs with minor allele frequency (MAF) less than 0.10 and those out of Hardy Weinberg Equilibrium (HWE) proportions (p<0.001) were removed from analyses. Ordinal regression was used to test for allelic and haplotypic association with grade 3 or 4 toxicities relative to 0, 1, and 2 toxicities, adjusting for age, genetic admixture index and treatment arm. To adjust for multiple testing, permutation analyses were performed on both single SNP and haplotype models.Results: Eighteen SNPs in FANCD2 and 38 SNPs in FANCA passed MAF and HWE proportion requirements. For FANCD2, 4 SNPs spanning 67.5 Kb (rs7648104, rs2272125 [coding SNP], rs6786638 and rs644215), were significantly associated with taxane-induced neuropathy (p<0.001) after controlling for multiple testing, with each SNP resulting in approximately a twofold increase in odds of severe taxane-induced neuropathy. Haplotype estimation showed that all 18 SNPs comprise a single haplotype. Two major (>1% frequency) haplotypes were found. The frequencies of the risk haplotype in cases (patients with grade 3 or 4 neuropathy) and controls (patients with ≤ grade 2 neuropathy) were 0.25 and 0.15, respectively. Ordinal regression analyses were highly significant (p<0.0005); patients with at least one copy of the risk haplotype had more than a twofold increased risk of grade 3 or 4 taxane-induced neuropathy (OR=2.2, 95% CI 1.44, 3.44). For FANCA, no SNPs or haplotypes were significantly associated with grade 3 or 4 neurotoxicity, either prior to or after correction for multiple testing.Conclusions: These results indicate that the Fanconi-Anemia pathway may be important for neurological sensitivity to taxanes, and that genotypic markers might be able to be used to identify patients at increased risk for severe taxane-induced neuropathy. Further studies will elucidate potential associations with survival outcomes.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2001.

Prognostic Factors and Long-Term Survivors in Inflammatory Breast Cancer

Background: Inflammatory Breast Cancer (IBC) carries a worse overall survival and demonstrates distinct clinicopathologic qualities which require refinement of prognostic indicators specific to IBC. We hypothesized that given IBC's typically rapid course, nodal status would not be a significant prognostic factor. We also investigated the impact of treatment with radiation and surgery on IBC survival.Material and Methods: Retrospective data from the Surveillance, Epidemiology, and End Results of the National Cancer Institute (SEER 13 and 17 registries) were used to evaluate the prognostic effects of nodal status, surgical resection, and radiation on mortality of patients with IBC. We compared survival between patients with or without positive lymph node status and treatment with radiation, surgery, and those patients treated with both. Data were subjected to multivariate statistical analysis.Results: A total of 3755 IBC patients were diagnosed and reported to SEER between 1995 and 2005. IBC survival appears independent of lymph node status with mean survival times of 34 months for node negative patients and 32 months for node positive patients (figure 1, p= 0.11). We identified 735 cases with adequate local treatment records and follow-up information. In this subset we compared survival between groups that received both surgery and radiation (SR), groups that received one of these therapies independently (S or R respectively), to those without either therapy (NT, no therapy) given positive lymph node status at diagnosis (fig. 2, p<0.001).Discussion: Our data suggests that the prognosis of IBC is not related to lymph node status at the time of diagnosis. Because patients with IBC amenable to surgical intervention or radiation are likely to have more favorable biology then those who progress on chemotherapy, it remains difficult to quantify the impact of local therapies. NCCN guidelines currently recommend first-line chemotherapy before moving to local treatments; therefore one limitation of our study is the assumption that centers reporting data to SEER follow NCCN guidelines. Of special interest is the substantial number of patients that show prolonged survival with local therapies. This supports previous reports that about 30% of patients who complete chemotherapy, surgery and radiation therapy may survive five years or more after IBC diagnosis.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4039.

Multiplexed AQUA-based assessment of SWOG 9313 shows prognostic value of continuous ER, PR and HER2 assessment

Abstract #704

Introduction: HER2 is expressed at high levels due to gene amplification in about 15% of breast cancer cases and it has been shown to be a poor prognostic marker. However, HER2 is also expressed in normal breast duct tissue, albeit a much lower levels. We hypothesized that continuous analysis of expression using AQUA will provide prognostic information beyond that attainable with conventional methods.
 Methods: A tissue microarray was made from 2123 cases of the 3122 patients accrued to SWOG 9313, in which sequential doxorubicin and cyclophosphamide (A-C) was compared to combination AC. A multiplexed assessment of HER2 and estrogen receptor (ER) was performed on the same slide using the immunofluoresence-based AQUA® method of automated quantitative analysis. Reproducibility and fidelity of multiplexing were determined for each marker by regression analysis.
 Results: As expected, both ER and PR were significantly predictive of disease-free survival (DFS) when both are tested as continuous variables, both adjusted for node status, tumor size, treatment and menopausal status (p-values 0.005 and <0.001, respectively). HER2, measured as a continuous variable showed a bi-phasic effect. It has been previously reported (Camp et al, Cancer Research 2003, 63;1445) that both the high and low expressers of HER2 have worse outcome (low levels are equivalent to that seen in normal breast ducts). Splitting the SWOG cohort by deciles shows that both the top and bottom decile have worse DFS than the middle 80% (log rank p=0.012). Also, modeling the hazard ratio as a function of concentration shows a U-shape relationship showing both high and low HER2 expression is associated with poorer DFS.
 Conclusions: The AQUA method provides a reproducible method of continuous measurement of ER, and HER2 on the same slide. In this cohort both ER and PR as continuous variable are highly prognostic, as expected, but multiplexing with HER2 did not affect outcome. Quantitative analysis demonstrated that both low and high levels of HER2 expression were associated with poor outcome. Studies are ongoing to determine the significance of this observation with respect to biological classifications of breast cancer and relationships with breast cancer therapies.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 704.

NSABP B-30: definitive analysis of quality of life (QOL) and menstrual history (MH) outcomes from a randomized trial evaluating different schedules and combinations of adjuvant therapy containing doxorubicin, docetaxel and cyclophosphamide in women with operable, node-positive breast cancer

Abstract #76

Background: QOL and MH outcomes were integrated into the NSABP B-30 trial as secondary outcomes to the efficacy analyses which are being presented separately. Explicit secondary aims of the NSABP B-30 study were 1) to compare toxicities among the regimens, 2) to compare QOL, and 3) to examine differences in amenorrhea and its relationship to symptoms, QOL, and efficacy. Here we examine the secondary aims of the study as a companion to the efficacy results that are presented separately.
 Materials and Methods: 5351 pts with cT1-3, N0-1, M0 were enrolled from 3/1/99 to 3/31/2004. 2170 were enrolled on the QOL study, and 2449 were enrolled on the MH study and were randomized to one of three treatment groups: Group 1 [doxorubicin (A) 60 mg/m2 and C 600 mg/m2 q 3 weeks (wks) x 4 followed by docetaxel (T) 100 mg/m2 q 3 wks x 4; Group 2 [A 50 mg/m2 and T 75 mg/m2 q 3 wks x 4]; Group 3 [A 50 mg/m2 T 75 mg/m2 and cyclophosphamide (C) 500 mg/m2 q 3 wks x 4]. All patients with ER-positive tumors received hormonal therapy after completing chemotherapy. Preliminary results from Group 1 have been reported previously (Swain, et al. Breast Cancer Res Treat, 2008).
 Results: The protocol specifies that 800 deaths are required for the definitive analysis of treatment, QOL, and MH outcomes, which are expected to occur by fall 2008. For this final report, results from a comparison of the three arms will be analyzed and presented.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 76.

Metabolism-perfusion mismatch as assessed by PET varies with breast cancer phenotype and predicts response to neoadjuvant chemotherapy

Abstract #6005

Background: Kinetic analysis of FDG and water PET can identify patterns of breast cancer metabolism and perfusion in patients receiving neoadjuvant chemotherapy (NC). Previously, we found that high pre-therapy glucose tumor metabolism relative to perfusion was associated with poor tumor pathologic response, early relapse, and death in patients with locally advanced breast cancer (LABC) treated with NC. This analysis examines tumor metabolism and perfusion as a function of tumor phenotype. Material and Methods: Tumor phenotype, defined by immunohistochemistry (IHC), was determined in 51 patients undergoing NC between 1995 and 2005. Luminal tumors were defined as those expressing either estrogen receptor (ER) or progesterone receptor (PR). The triple-negative (TN) phenotype was defined as ER and PR negative without HER2 overexpression by IHC or amplification by FISH. HER2 phenotype showed HER2 overexpression or amplification but were ER/PR negative. Women with LABC underwent dynamic [18F]-FDG and [15O]-water PET scans prior to NC. The FDG metabolic rate (MRFDG) and transport (FDG K1) parameters were calculated; blood flow (BF) was estimated from the water PET scan. Response to NC was determined from surgical specimens with pathologic complete response (pCR) defined as eradication of invasive tumor in the breast vs. other. Results: Of the tumors studied, 16 (31%) were TN, 30 (59%) were luminal, and 5 (10%) were HER2. pCR was observed in 4/16 (25%) TN tumors (95% CI: 0.10-0.50) compared to only 4/30 (13%) of luminal tumors (95% CI: 0.05-0.30) and 3/5 HER2 tumors. Linear regression of the association between PET parameters and phenotype (TN vs. luminal) found that TN was associated with higher MRFDG (p=0.007) and MRFDG/BF ratio (p=0.02), but not with BF (p=0.27). Only patients with low pre-therapy MRFDG/BF ratio (<35 umol/mL) achieved a pCR. Using this value as an ad-hoc cutoff, 4/7 (57%) of TN patients with low ratios had a pCR, while 0/9 with higher ratios had pCR. In contrast, only 4/21 (19%) of the luminal patients with low ratios had a pCR (one-sided mid-p=0.04 for TN vs. luminal pCR rate for patients with MRFDG/BF < 35 umol/mL). Discussion: These results demonstrate heterogeneity in breast tumor metabolism and perfusion as assessed by PET, and suggest a clinically relevant association between PET parameters and tumor phenotypes. The high MRFDG/BF ratio that predicts poor response to NC is more common in TN tumors; whereas in luminal or HER2 tumors, high MRFDG is generally matched with higher BF. Measurement of tumor metabolism and perfusion may identify a subset of tumors which are unlikely to respond to NC. Identification of such tumors may direct therapy toward those biologic targets most likely to overcome resistance.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6005.

Intent-to-treat analysis of the placebo-controlled trial of letrozole for extended adjuvant therapy in early breast cancer: NCIC CTG MA.17

BACKGROUND

MA.17 evaluated letrozole or placebo after 5 years of tamoxifen and showed significant improvement in disease-free survival (DFS) for letrozole [hazard ratio (HR) 0.57, P = 0.00008]. The trial was unblinded and placebo patients were offered letrozole.

PATIENTS AND METHODS

An intent-to-treat analysis of all outcomes, before and after unblinding, on the basis of the original randomization was carried out.

RESULTS

In all, 5187 patients were randomly allocated to the study at baseline and, at unblinding, 1579 (66%) of 2383 placebo patients accepted letrozole. At median follow-up of 64 months (range 16-95), 399 recurrences or contralateral breast cancers (CLBCs) (164 letrozole and 235 placebo) occurred. Four-year DFS was 94.3% (letrozole) and 91.4% (placebo) [HR 0.68, 95% confidence interval (CI) 0.55-0.83, P = 0.0001] and showed superiority for letrozole in both node-positive and -negative patients. Corresponding 4-year distant DFS was 96.3% and 94.9% (HR 0.80, 95% CI 0.62-1.03, P = 0.082). Four-year overall survival was 95.1% for both groups. The annual rate of CLBC was 0.28% for letrozole and 0.46% for placebo patients (HR 0.61, 95% CI 0.39-0.97, P = 0.033).

CONCLUSIONS

Patients originally randomly assigned to receive letrozole within 3 months of stopping tamoxifen did better than placebo patients in DFS and CLBC, despite 66% of placebo patients taking letrozole after unblinding.

Screening for clonal hematopoiesis as a predictive marker for development of t-AML following adjuvant therapy for breast cancer (S0012)

11051

Background: A serious complication associated with breast cancer treatment is the increased risk for development of therapy-related acute myeloid leukemia (t-AML). To evaluate and possibly identify patients (pts) at high risk for development of t-AML, the Southwest Oncology Group asked whether dose-intensive adjuvant regimens for high risk breast cancer pts induced genetic damage to hematopoietic stem cells (HSC), defined by the emergence of clonal hematopoiesis, an early marker of HSC damage. Methods: 274 pts consented to the clonal hematopoiesis study objective of S0012, a randomized clinical trial of standard doxorubicin and cyclophosphamide followed by weekly paclitaxel (arm 1, 129 pts) vs. weekly doxorubicin and daily oral cyclophosphamide plus G-CSF followed by weekly paclitaxel (arm 2, 145 pts) as neoadjuvant therapy for inflammatory and locally advanced breast cancer. Two different clonality assays were used: the HUMARA (HUMan Androgen Receptor) Assay to estimate the incidence of early genetic damage by clonal proliferation and microsatellite instability (MSI) testing at 5 loci (Bat 26, Bat 40, APC, Mfd, D2S123), common ‘hotspots‘ in t-AML, to screen for loss of heterozygosity or defective DNA mismatch repair mechanisms. Blood samples were evaluated prior to treatment and at 6 and 12 mos post-surgery for emergence of clonal hematopoiesis. Results: Of the 274 pts enrolled, follow-up clonal hematopoiesis samples were available for 195 pts; 96 pts on arm 1 and 99 pts on arm 2. Both HUMARA and MSI results were negative for clonal hematopoiesis in 96% of samples analyzed. In 14 cases, the HUMARA assay suggested that a clonal population was present, but MSI analysis was negative. No cases were HUMARA+/MSI+. With a median follow-up of 19.6 mos, only one pt has developed t-AML 3 yr 5 mos post randomization. Her clonal hematopoiesis test samples at 6 and 12 mos following treatment were negative. Conclusions: Clonal hematopoiesis assays performed within the first year following neoadjuvant therapy and surgery on S0012 failed to identify an emerging clonal HSC population. Longer clinical follow-up will be necessary to define the positive predictive value of detecting clonal hematopoiesis in the 14 HUMARA+/MSI- cases as a harbinger of t-AML.

No significant financial relationships to disclose.

Use of changes in blood flow PET measurements to predict post-therapy lymph node status among locally advanced breast cancer patients

575

Background: Response to neoadjuvant therapy in the primary tumor and nodal metastasis predicts benefit to patients as shown in several large clinical trials. We have previously shown that changes in tumor blood flow (BF) measured by [15O]-water PET predict pathologic primary tumor response. We now test whether primary tumor blood flow changes also predict axillary nodal metastases response and post-therapy lymph node status among women with locally advanced breast cancer (LABC) receiving neoadjuvant chemotherapy. Methds: Fifty-five women with a primary diagnosis of LABC underwent dynamic [15O]-water PET scans prior to and at midpoint of neoadjuvant chemotherapy. We evaluated associations between tumor BF changes and pathologic primary tumor response: categorized as complete (CR), partial (PR) or no response (NR). We also assessed the relationship between primary tumor BF changes and post-therapy axillary lymph node status, categorizing the high risk (HR) group as 4+ nodes with extracapsular extension (ECE, n=12) versus the lower risk (LR) group with either fewer than 4+ nodes or without ECE (n=43). Results: The median changes in BF versus tumor response were: CR = -77%, PR = -40%, and, NR = +20% (P = <0.001). For axillary node response, the median BF change among HR patients was +20% versus - 49% among LR patients (P = 0.004). Eight of 17 patients with an increase in tumor blood flow were HR whereas 4/38 patients with decreased tumor blood flow were HR (P = 0.002). Conclusions: Change in primary tumor blood flow over the course of neoadjuvant chemotherapy predicts pathologic response to treatment with a substantial decrease observed among CRs. An increase in primary tumor BF with treatment portends significant residual primary tumor and a nearly 50% chance of very high-risk nodal disease post-therapy.

No significant financial relationships to disclose.

Tumor metabolism, blood flow changes, and prognosis by positron emission tomography: A prospective cohort of locally advanced breast cancer patients

506

Background: Breast cancer patients with locally advanced tumors receive preoperative chemotherapy to provide early systemic treatment and assess in-vivo tumor response. Positron emission tomography (PET) has been used to follow tumor response to therapy, as pathologic response is predictive of patient outcome. We evaluated the prognostic utility of serial quantitative PET tumor blood flow (BF) and metabolism measurements. Methods: Fifty-five women with a primary diagnosis of locally advanced breast carcinoma (LABC) underwent dynamic [18F]-FDG and [15O]-water PET scans prior to and at midpoint of neoadjuvant chemotherapy. The FDG metabolic rate (MRFDG), transport (K1), and flux (Ki) parameters were calculated, and tumor blood flow was estimated from the [15O]-water study. Associations between tumor BF and MRFDG measurements and disease-free survival (DFS) and overall survival (OS) were evaluated using the Cox proportional hazards model. Results: Patients that had an increase in BF and K1, from baseline to mid-therapy measurements, had elevated recurrence and mortality risks compared to patients that had reductions in BF and MRFDG values. In multivariate analysis, changes in BF and K1 remained independent prognostic indicators of DFS and OS survival. Conclusions: PET measurements of tumor response prior to completion of neoadjuvant chemotherapy were predictive of patient outcome. Patients that failed to have a decline in BF and K1 experienced higher risks of recurrence and mortality that was largely independent of clinical tumor characteristics assessed in this study. These results suggest that tumor perfusion, measured directly by [15O]-water or indirectly by dynamic FDG PET, is highly predictive of outcome in neoadjuvantly treated breast cancer.

No significant financial relationships to disclose.

Adjuvant chemotherapy in elderly patients: An analysis of National Cancer Institute of Canada Clinical Trials Group and Intergroup BR.10

7009

Background: Recent trials have shown significant survival benefit from adjuvant chemotherapy after resection of NSCLC. Whether elderly patients tolerate platinum-based adjuvant chemotherapy and derive the same survival advantage is unknown. This retrospective study evaluated the influence of age on survival, chemotherapy delivery and toxicity in NCIC CTG BR.10. Methods: Pretreatment characteristics and survival benefit from treatment were compared for patients ≤65 & >65. Chemotherapy delivery and toxicity were compared for 213 treated patients. Results: There were 327 young and 155 elderly patients. Baseline prognostic factors by age were similar with the exception of histology (adeno 58% young, 43% elderly; squamous 32% young, 49% elderly; p=0.001) and PS (PS 0 53% young, 41% elderly; p=0.01). Overall survival by age showed a trend favoring the young in univariate (HR 0.77, CI 0.58–1.04, p=0.084) and multivariate analyses (HR 0.75, CI 0.56–1.01, p=0.059). Patients >75 years had significantly shorter survival than those aged 66–74 (HR 1.95, CI 1.11–3.41, p=0.02). Overall survival for patients >65 was significantly better with chemotherapy v observation (HR 0.61, CI 0.38–0.98, p=0.04). Chemotherapy administration and toxicity were evaluated in 63 elderly and 150 young patients. Mean dose intensities of vinorelbine (V) and cisplatin (C) were 13.2 and 18.0 in the young and 9.9 and 14.1 in the elderly (V p=0.0004; C p=0.001). The elderly received significantly fewer doses of V (p=0.014) and C (p=0.006). Fewer elderly patients completed treatment and more refused treatment compared to the young (p=0.03). There were no significant differences in toxicities, G-CSF use or hospitalization by age group, except for myalgias and mood alteration (more frequent among the young). Six of 126 deaths (4.8%) in the young were from non-malignant causes v 12 of 71 (16.9%) in the elderly (p=0.008). Conclusions: In spite of receiving less chemotherapy than young patients, adjuvant chemotherapy improves overall survival in patients aged >65 with acceptable toxicity. Adjuvant chemotherapy should not be withheld from elderly patients, although patients >75 years of age require further study.

No significant financial relationships to disclose.

SWOG 0338: A phase II trial of imatinib mesylate in combination with capecitabine in metastatic breast cancer

10529

Background: Imatinib mesylate targets c-kit and platelet derived growth factor receptor (PDGFR) tyrosine kinases, and both are variably expressed in breast cancer. Inhibition of PDGFR by imatinib mesylate may decrease tumor interstitial pressure and improve delivery of chemotherapy. Based on preclinical synergy, SWOG conducted a phase II trial in metastatic breast cancer. Methods: Patients were eligible if they had adenocarcinoma of the breast that had progressed on at least 1 but ≤ 2 prior chemotherapy regimens for metastatic disease. No prior 5-FU or capecitabine for metastatic disease was allowed. Patients had to be > 18 years with a Zubrod performance status ≤ 2 and have adequate organ function. Patients with brain metastases were ineligible. Patients received imatinib mesylate 400 mg orally daily and capecitabine 1000 mg/m2 orally twice daily on days 1–14 of a 21-day cycle. If tolerated, the imatinib mesylate was increased to 600 mg daily in subsequent cycles. This was a 2-stage design with 25 patients with measurable disease accrued in the first stage. A total of 70 patients was planned, including those with nonmeasurable disease, if accrual proceeded to the second stage. The primary endpoint was to determine the confirmed response rate (RR) to the combination therapy. Secondary endpoints were to estimate the 6-month progression free survival, to determine the toxicities, and to explore c-kit and PDGFR in this population. Results: 27 patients were accrued; 6 were ineligible. 19 patients received therapy and were evaluable for toxicity. The median age was 59 years (36–78). Four responses were seen: 1 complete, 1 confirmed partial, and 2 unconfirmed partial (RR 21%). The 6-month progression free survival was 16%. There were no grade 4 toxicities. The most common grade 3 toxicities, seen in 7 patients, were diarrhea, fatigue, and hand-foot syndrome. As 2 of the 4 responses were unconfirmed, accrual did not proceed to the second stage. Conclusions: The combination of imatinib mesylate and capecitabine was well tolerated in patients with metastatic breast cancer, but the RR was not better than was seen in a prior study of single agent capecitabine. Correlative studies to explore c-kit, PDGFR, and estrogen receptor expression and response are in progress.

No significant financial relationships to disclose.

Advanced bronchioloalveolar carcinoma: a phase II trial of paclitaxel by 96-hour infusion (SWOG 9714): a Southwest Oncology Group study

BACKGROUND

There are no published prospective trials of chemotherapy for advanced bronchioloalveolar carcinoma (BAC), a subtype of non-small-cell lung cancer for which there is no current standard therapy. This phase II study assesses the efficacy and toxicity of 96-h paclitaxel in chemotherapy-naive patients with advanced BAC.

PATIENTS AND METHODS

Patients with histologically confirmed stage IIIB (with pleural effusion) or stage IV BAC were eligible. Treatment consisted of paclitaxel 35 mg/m2/24 h continuously infused over 96 h (days 1-4) every 21 days for up to six courses.

RESULTS

A total of 58 eligible patients were enrolled. The objective response rate was 14% (all partial responses, 9% confirmed); 40% of patients demonstrated stable disease. The median progression-free and overall survivals were 5 and 12 months, respectively. Grade 3 or greater toxicities included neutropenia/granulocytopenia (43%), febrile neutropenia (12%), infection (22%), and stomatitis/pharyngitis (10%); there were five treatment-related deaths.

CONCLUSIONS

S9714 represents the first prospective multi-institutional cooperative group trial focusing on treatment outcomes in BAC. Studies targeting this population are feasible, and while first-line paclitaxel administered as a prolonged infusion is active in this setting, toxicities limits the utility of this regimen. S9714 serves as a historical control for BAC patients against which future therapeutic approaches can be compared.

Cell transplantation for treatment of acute myocardial infarction: unique capacity for repair by skeletal muscle satellite cells

An adult heart injured by an ischemic episode has a limited capacity to regenerate. We administered three types of adult guinea pig cells [cardiomyocytes (CMs), cardiac fibroblasts (CFs), and skeletal myoblasts (Mbs)] to compare their suitability for repair of acute myocardial infarction. We used confocal fluorescent microscopy and a variety of specific immunomarkers and echocardiography to provide anatomic evidence for the viability of such cells and their possible functional beneficial effects. All cells were transfected with adenovirus-containing beta-galactosidase gene so that migration from the injection sites could be traced. Both freshly isolated CMs as well as CFs were found concentrated in the infarcted zone; these cells survived for at least 2 wk posttransplantation. Transplanted CMs were regularly striated and grew long projections that could form gap junctions with native CMs, which was evidenced by connexin43 labeling. In addition, CM transplantation resulted in increased angiogenesis in the infarcted areas. In contrast, transplanted CFs did not appear to make any gap junctional contacts with native CMs nor did they enhance local angiogenesis. Mbs cultured for 7 days and transfected Mbs were identified 7 days posttransplantation in the infarcted area. During that time and thereafter, Mbs proliferated and differentiated into myotubes that formed new, regularly striated myofibers that occupied most (50-70%) of the infarcted area by 2-3 wk. These newly formed myofibers maintained their Mb skeletal muscle origin as evidenced by their capacity to express myogenin and fast skeletal myosin. This skeletal phenotype appeared to downregulate with time, and Mbs partially transdifferentiated into a cardiac phenotype as indicated by labeling for cardiac-specific troponin T and cardiac myosin heavy chain. By the third week posttransplantation, new myofibers formed apparent contacts with the native CMs via putative gap junctions that expressed connexin43. Myocardial performance of animals that were successfully transplanted with Mbs was improved.

Single-nucleotide polymorphisms and haplotype analysis in beta-defensin genes in different ethnic populations

Beta-defensins are cationic antimicrobial peptides expressed by epithelial cells and exhibit antibacterial, antifungal, and antiviral properties. The defensins are part of the innate host defense network and may have a significant protective role in the oral cavity and other mucosa. Defects or alteration in expression of the beta-defensins may be associated with susceptibility to infection and mucosal disorders. We examined the occurrence of single-nucleotide polymorphisms (SNPs) in the human beta-defensin genes DEFB1 and DEFB2 encoding human beta-defensin-1 and -2 (hBD-1, hBD-2), respectively, in five ethnic populations and defined haplotypes in these populations. Fifteen SNPs were identified in both DEFB1 and DEFB2. Coding region SNPs were found in very low frequency in both genes. One nonsynonymous DEFB1 SNP, G1654A (Val --> Ile), and one nonsynonymous DEFB2 SNP, T2312A (Leu --> His), were identified. Seven sites in each gene exhibited statistically significant differences in frequency between ethnic groups, with the greatest variation in the promoter and in the 5'-untranslated region of DEFB1. DEFB1 displayed 10 common haplotypes, including one cosmopolitan haplotype. Eight common haplotypes were found in DEFB2, including one cosmopolitan haplotype shared among all five ethnic groups. Our results show that genotypic variability among ethnic groups will need to be addressed when performing associative genetic studies of innate defense mechanisms and susceptibility to disease.

The influence of gender on survival and tumor recurrence following adjuvant therapy of completely resected stages II and IIIa non-small cell lung cancer

This study evaluates the influence of gender on survival and tumor recurrence following adjuvant therapy of completely resected stages II and IIIa non-small cell lung cancer (NSCLC). The Eastern Cooperative Oncology Group conducted a randomized prospective trial of adjuvant therapy in patients with completely resected stages II and IIIa NSCLC. A laboratory correlative study assessed the prevalence and prognostic significance of p53 and K-ras mutations. Patients were randomized to receive either radiotherapy (RT) alone or four cycles of cisplatin and VP-16 administered concurrently with radiotherapy (CRT). Median survival was 35 months for the 285 men and 41 months for the 203 women enrolled in the study (P = 0.12). The relative risk (RR) of death for men vs women was 1.19 (95% confidence interval [CI], 0.95-1.49). Median survival of the 147 men and 95 women randomized to the RT arm was 39 months each (P = 0.35). Median survival of the 138 men and 108 women randomized to the CRT arm was 30 and 42 months, respectively (P = 0.18). Disease recurrence patterns were similar between the genders. Univariate and multivariate analyses demonstrated improved survival for women with tumors of non-squamous histology (P < 0.01). The distribution of p53 and K-ras mutations was similar between the genders and had no influence on survival. Gender does not influence survival following adjuvant RT or CRT administered to patients with completely resected stages II and IIIa NSCLC. However, women with non-squamous histology have increased survival when compared to men.