Real-World Analysis of the Clinical and Economic Impact of the 21-Gene Recurrence Score (RS) in Invasive Lobular Early-Stage Breast Carcinoma in Ireland

Background: This study, using real-world data, assesses the impact of RS testing on treatment pathways and the associated economic consequences of such testing. This paper pertains to lobular breast cancer. Methods: A retrospective, observational study was undertaken between 2011 and 2019 on a cross-section of hormone receptor-positive (HR+), HER2-negative, lymph node-negative, early-stage breast cancer patients. All patients had ILC and had RS testing in Ireland. The patient population is representative of the national population. Patients were classified as low (RS ≤ 25) or high (RS > 25) risk. Patients aged ≤50 were stratified as low (RS 0-15), intermediate (RS 16-25), or high risk (RS > 25). Results: A total of 168 patients were included, most of whom had grade 2 (G2) tumors (n = 154, 92%). Overall, 155 patients (92.3%) had low RS (≤25), 12 (7.1%) had high RS (>25), and 1 (0.6%) had unknown RS status. In 29 (17.5%) patients aged ≤50 at diagnosis, RS was ≤15 in 16 (55%), 16-20 in 6 (21%), 21-25 in 5 (17%), >25 in 1 (3.5%), and unknown in 1 (3.5%). Post RS testing, 126 patients (78%) had a change in chemotherapy recommendation; all to hormone therapy. In total, only 35 patients (22%) received chemotherapy. RS testing achieved a 75% reduction in chemotherapy use, resulting in savings of €921,543.84 in treatment costs, and net savings of €387,283.84. Conclusions: The use of this test resulted in a 75% reduction in chemotherapy and a significant cost savings in our publicly funded health system.

A careful reassessment of anthracycline use in curable breast cancer

It has been over three decades since anthracyclines took their place as the standard chemotherapy backbone for breast cancer in the curative setting. Though the efficacy of anthracycline chemotherapy is not debatable, potentially life-threatening and long-term risks accompany this class of agents, leading some to question their widespread use, especially when newer agents with improved therapeutic indices have become available. Critically assessing when to incorporate an anthracycline is made more relevant in an era where molecular classification is enabling not only the development of biologically targeted therapeutics but also is improving the ability to better select those who would benefit from cytotoxic agents. This comprehensive analysis will present the problem of overtreatment in early-stage breast cancer, review evidence supporting the use of anthracyclines in the pre-taxane era, analyze comparative trials evaluating taxanes with or without anthracyclines in biologically unselected and selected patient populations, and explore published work aimed at defining anthracycline-sensitive tumor types.

NRG Oncology/NSABP B-47 menstrual history study: impact of adjuvant chemotherapy with and without trastuzumab

The NRG Oncology/NSABP B-47 menstrual history (MH) study examined trastuzumab effects on menstrual status and associated circulating reproductive hormones. MH was evaluated by questions related to hysterectomy, oophorectomy, and reported menstrual changes. Pre/perimenopausal women were assessed at entry, 3, 6, 12, 18, 24, 30, and 36 months. Consenting women had estradiol and FSH measurement at entry, 3, 6, 12, 18, and 24 months. Logistic regression determined predictors of amenorrhea and hormone levels at 12, 24, and 36 months. Between 2/8/2011 and 2/10/2015, 3270 women with node-positive/high-risk node-negative HER2-low breast cancer were enrolled. There were 1,458 women enrolled in the MH study; 1231 consented to baseline blood samples. Trastuzumab did not contribute to a higher amenorrhea rate. Amenorrhea predictors were consistent with earlier studies; however, to our knowledge, this is the largest prospective study to include serial reproductive hormone measurements to 24 months and clinical amenorrhea reports to 36 months. These data can help to counsel patients regarding premature menopause risk.

NSABP B-47/NRG Oncology Phase III Randomized Trial Comparing Adjuvant Chemotherapy With or Without Trastuzumab in High-Risk Invasive Breast Cancer Negative for HER2 by FISH and With IHC 1+ or 2

PURPOSE

Adjuvant trastuzumab reduces invasive breast cancer (IBC) recurrence and risk for death in patients with HER2-amplified or overexpressing IBC. A subset of patients in the landmark trastuzumab adjuvant trials who originally tested HER2-positive but were HER2-negative by central HER2 testing appeared to possibly benefit from trastuzumab. The objective for the NSABP B-47 trial was to determine whether the addition of trastuzumab to adjuvant chemotherapy (CRx) would improve invasive disease-free survival (IDFS) in patients with HER2-negative breast cancer.

PATIENTS AND METHODS

A total of 3,270 women with high-risk primary IBC were randomly assigned to CRx with or without 1 year of trastuzumab. Eligibility criteria included immunohistochemistry (IHC) score 1+ or 2+ with fluorescence in situ hybridization ratio (FISH) < 2.0 or, if ratio was not performed, HER2 gene copy number < 4.0. CRx was either docetaxel plus cyclophosphamide or doxorubicin and cyclophosphamide followed by weekly paclitaxel for 12 weeks.

RESULTS

At a median follow-up of 46 months, the addition of trastuzumab to CRx did not improve IDFS (5-year IDFS: 89.8% with CRx plus trastuzumab [CRxT] v 89.2% with CRx alone; hazard ratio [HR], 0.98; 95% CI, 0.76 to 1.25; P = .85). These findings did not differ by level of HER2 IHC expression, lymph node involvement, or hormone-receptor status. For distant recurrence-free interval, 5-year estimates were 92.7% with CRxT compared with 93.6% for CRx alone (HR, 1.10; 95% CI, 0.81 to 1.50; P = .55) and for overall survival (OS) were 94.8% with CRxT and 96.3% in CRx alone (HR, 1.33; 95% CI, 0.90 to 1.95; P = .15). There were no unexpected toxicities from the addition of trastuzumab to CRx.

CONCLUSION

The addition of trastuzumab to CRx did not improve IDFS, distant recurrence-free interval, or OS in women with non-HER2-overexpressing IBC. Trastuzumab does not benefit women without IHC 3+ or FISH ratio-amplified breast cancer.

BET Inhibition as a Rational Therapeutic Strategy for Invasive Lobular Breast Cancer

PURPOSE

Invasive lobular carcinoma (ILC) is a subtype of breast cancer accounting for 10% of breast tumors. The majority of patients are treated with endocrine therapy; however, endocrine resistance is common in estrogen receptor-positive breast cancer and new therapeutic strategies are needed. Bromodomain and extraterminal inhibitors (BETi) are effective in diverse types of breast cancer but they have not yet been assessed in ILC.

EXPERIMENTAL DESIGN

We assessed whether targeting the BET proteins with JQ1 could serve as an effective therapeutic strategy in ILC in both 2D and 3D models. We used dynamic BH3 profiling and RNA-sequencing (RNA-seq) to identify transcriptional reprograming enabling resistance to JQ1-induced apoptosis. As part of the RATHER study, we obtained copy-number alterations and RNA-seq on 61 ILC patient samples.

RESULTS

Certain ILC cell lines were sensitive to JQ1, while others were intrinsically resistant to JQ1-induced apoptosis. JQ1 treatment led to an enhanced dependence on antiapoptotic proteins and a transcriptional rewiring inducing fibroblast growth factor receptor 1 (FGFR1). This increase in FGFR1 was also evident in invasive ductal carcinoma (IDC) cell lines. The combination of JQ1 and FGFR1 inhibitors was highly effective at inhibiting growth in both 2D and 3D models of ILC and IDC. Interestingly, we found in the RATHER cohort of 61 ILC patients that 20% had FGFR1 amplification and we showed that high BRD3 mRNA expression was associated with poor survival specifically in ILC.

CONCLUSIONS

We provide evidence that BETi either alone or in combination with FGFR1 inhibitors or BH3 mimetics may be a useful therapeutic strategy for recurrent ILC patients.

Abstract PD5-09: Immune parameters associated with survival in triple negative and HER2-positive breast cancer patients with 10 years of follow-up

The clinical utility of tumor-infiltrating lymphocytes (TIL) is actively being investigated in breast cancer (BC). It is unclear whether TIL spatial location and organization in tertiary lymphoid structures (TLS) have an impact on prognosis. Additionally, the significance of PD-1 and PD-L1 expression is being debated due to conflicting data from several studies. We hypothesize that the presence, extent and spatial location of multiple immune biomarkers, reflecting ongoing immune responses, will be consistently associated with a good prognosis in highly infiltrated BC [triple-negative (TNBC) and HER2+].

The relationship between these immune biomarkers and clinical outcome was examined in the TNBC and HER2+ cohorts of node-positive BC patients enrolled in the BIG 02-98 adjuvant phase III trial with available material for immunohistochemical (IHC) labeling (N=113 and N=136, respectively). HER2+ patients did not receive trastuzumab. Dual IHC staining was performed on full-face consecutive tissue sections. Scoring was independently performed by two pathologists, blinded to the clinical data, and included: global, intratumoral and stromal TIL and TLS, assessed on CD3/CD20 slides; the percentage and location of PD-1 and PD-L1 expression, assessed on PD-1/PD-L1 slides. TIL were considered as a categorical variable with different cut-offs used for each parameter and for each cohort (TNBC and HER2+). Invasive disease-free survival (I-DFS) and overall survival (OS) were analyzed (median follow-up: 10 years). Cox proportional hazard models were used for survival analyses.

The TNBC cohort revealed an association between global TIL and outcome [adjusted hazard ratio (HR) for I-DFS: 0.27 (0.15-0.51); OS: 0.26 (0.13-0.53)]. Similar results were observed for stromal and intratumoral TIL. PD-L1 expression within TLS was an independent predictor of OS, after adjustment for tumor size and age [HR: 0.30 (0.09-0.99)]. Multivariate analysis reveals this effect was principally driven by high stromal TIL (&gt;17.5% based on CD3/CD20 assessment) (χ2 OS: p=0.009). In contrast, no significant prognostic associations were found in the overall HER2+ cohort. However high T cell TIL were associated with improved I-DFS and OS in the ER-/HER2+ group [I-DFS: 0.34 (0.14-0.80); OS: 0.32 (0.12-0.86)] and stromal TIL were associated with improved I-DFS in the ER+/HER2+ group [HR: 0.29 (0.09-0.94)] (univariate analyses). No significant associations between the number of TLS nor the expression of PD-1 with outcomes were observed in either cohorts.

The presence of PD-L1+ TLS, driven by high baseline TIL, was associated with an excellent prognosis in node-positive TNBC. This observation might reflect specific immune activities taking place in these mini lymph node-like structures adjacent to the tumor bed where specific antitumor memory immune responses could be generated. No different prognostic impact was observed when analyzing TIL spatial location. Although the statistical power of the study might be limited, in line with previous findings our data reveal that, among the immune parameters evaluated, TIL are the strongest predictor of outcome in TNBC, while PD-L1+ TLS could be a new and important parameter that requires further investigation.

Citation Format: Solinas C, de Wind A, Van den Eynden G, Ameye L, Garaud S, De Silva P, Boisson A, Noel G, Langouo Fontsa M, Buisseret L, de Azambuja E, Francis PA, Di Leo A, Crown JP, Sotiriou C, Larsimont D, Paesmans M, Piccart-Gebhart M, Willard-Gallo K. Immune parameters associated with survival in triple negative and HER2-positive breast cancer patients with 10 years of follow-up [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD5-09.

Trastuzumab Emtansine for Residual Invasive HER2-Positive Breast Cancer

BACKGROUND

Patients who have residual invasive breast cancer after receiving neoadjuvant chemotherapy plus human epidermal growth factor receptor 2 (HER2)-targeted therapy have a worse prognosis than those who have no residual cancer. Trastuzumab emtansine (T-DM1), an antibody-drug conjugate of trastuzumab and the cytotoxic agent emtansine (DM1), a maytansine derivative and microtubule inhibitor, provides benefit in patients with metastatic breast cancer that was previously treated with chemotherapy plus HER2-targeted therapy.

METHODS

We conducted a phase 3, open-label trial involving patients with HER2-positive early breast cancer who were found to have residual invasive disease in the breast or axilla at surgery after receiving neoadjuvant therapy containing a taxane (with or without anthracycline) and trastuzumab. Patients were randomly assigned to receive adjuvant T-DM1 or trastuzumab for 14 cycles. The primary end point was invasive disease-free survival (defined as freedom from ipsilateral invasive breast tumor recurrence, ipsilateral locoregional invasive breast cancer recurrence, contralateral invasive breast cancer, distant recurrence, or death from any cause).

RESULTS

At the interim analysis, among 1486 randomly assigned patients (743 in the T-DM1 group and 743 in the trastuzumab group), invasive disease or death had occurred in 91 patients in the T-DM1 group (12.2%) and 165 patients in the trastuzumab group (22.2%). The estimated percentage of patients who were free of invasive disease at 3 years was 88.3% in the T-DM1 group and 77.0% in the trastuzumab group. Invasive disease-free survival was significantly higher in the T-DM1 group than in the trastuzumab group (hazard ratio for invasive disease or death, 0.50; 95% confidence interval, 0.39 to 0.64; P<0.001). Distant recurrence as the first invasive-disease event occurred in 10.5% of patients in the T-DM1 group and 15.9% of those in the trastuzumab group. The safety data were consistent with the known safety profile of T-DM1, with more adverse events associated with T-DM1 than with trastuzumab alone.

CONCLUSIONS

Among patients with HER2-positive early breast cancer who had residual invasive disease after completion of neoadjuvant therapy, the risk of recurrence of invasive breast cancer or death was 50% lower with adjuvant T-DM1 than with trastuzumab alone. (Funded by F. Hoffmann-La Roche/Genentech; KATHERINE ClinicalTrials.gov number, NCT01772472 .).

Abstract P2-05-02: Functional genomic screening identifies ubiquitin-specific protease 11 (USP11) as a novel regulator of ER-alpha transcription in breast cancer

Approximately 70% of breast cancers overexpress the estrogen receptor α (ERα) and depend on this key transcriptional regulator for growth and differentiation. The discovery of novel mechanisms controlling ERα function represent major advances in our understanding of breast cancer progression and potentially offer attractive new therapeutic opportunities. Here, we investigated the role of deubiquitinating enzymes (DUBs), which act to remove ubiquitin moieties from proteins, in regulating transcriptional activity of ERα in breast cancer.

To identify DUBs involved in the regulation of ERα transcriptional activity, we performed an RNAi loss-of-function screen using a library of shRNA vectors targeting all human DUB genes. The DUB library consisted of pools of four non-overlapping shRNAs targeting all 108 known or putative DUBs (432 shRNAs in total). We found that suppression of a number of DUBs markedly repressed or enhanced the activity of an estrogen-response-element (ERE) luciferase reporter following estradiol (E2) stimulation. Of particular interest, suppression of the BRCA2-associated DUB, USP11, was found to down-regulate ERα transcriptional activity.

Subsequent validation using two individual siRNAs targeted to USP11 revealed a notable reduction in expression of endogenous ERα target genes in the ZR-75-1 cell line, as quantified using qRT-PCR. Further validation was carried out in a HEK293T USP11 knockout cell line, where reduced activity of an ERE-luciferase reporter was detected when compared to wild-type cells. This phenotype was rescued with a USP11 overexpression vector, both in the presence and absence of E2. Furthermore, USP11 expression was found to be upregulated in the estrogen-independent cell line LCC1 when compared to their parental MCF7 cells. Knockdown of USP11 in LCC1 cells resulted in decreased mRNA expression of a panel of ERα target genes, while RNA-seq revealed a downregulation of several putative ERα target genes and a downregulation of many cell cycle-associated proteins.

To support the prognostic relevance of USP11, immunohistochemical staining of a breast cancer tissue microarray (103 ER+ patients available for final analysis) was performed. Kaplan-Meier analysis of this cohort revealed a highly significant association between high USP11 expression and poor overall (p=0.030) and breast cancer-specific survival (p=0.041). In silico analysis of publically available breast cancer gene expression datasets further supported an association between high USP11 mRNA levels and poor prognosis. We observed a significant correlation between high expression of USP11 mRNA in ER-positive patients and poor distant metastasis-free survival (HR 2, CI 1.37-2.91, p=0.00023). This correlation was also significant in ER-positive patients who had received tamoxifen only (HR 2.9, CI 1.63-5.15, p=0.00015).

These results suggest a role for USP11 in driving cellular growth and identify USP11 as novel therapeutic target in breast cancer.

Citation Format: Dwane L, Das S, Moran B, O'Connor AE, Mulrane L, Dirac AM, Jirstrom K, Crown JP, Bernards R, Gallagher WM, Ní Chonghaile T, O'Connor DP. Functional genomic screening identifies ubiquitin-specific protease 11 (USP11) as a novel regulator of ER-alpha transcription in breast cancer [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 P2-05-02.

Abstract 3040: Functional genomic screening identifies USP11 as a novel regulator of ERα transcription in breast cancer

Approximately 70% of breast cancers overexpress the estrogen receptor α (ERα) and depend on this key transcriptional regulator for growth and differentiation. The discovery of novel mechanisms controlling ERα function represent major advances in our understanding of breast cancer progression and potentially offer attractive new therapeutic opportunities. Here, we investigated the role of deubiquitinating enzymes (DUBs), which act to remove ubiquitin moieties from proteins, in regulating transcriptional activity of ERα in breast cancer.

To identify DUBs involved in the regulation of ERα transcriptional activity, we performed an RNAi loss-of-function screen using a library of shRNA vectors targeting all human DUB genes. The DUB library consisted of pools of four non-overlapping shRNAs targeting all 108 known or putative DUBs (432 shRNAs in total). We found that suppression of a number of DUBs markedly repressed or enhanced the activity of an estrogen-response-element (ERE) luciferase reporter following estradiol (E2) stimulation. Of particular interest, suppression of the BRCA2-associated DUB, USP11, was found to down-regulate ERα transcriptional activity.

Subsequent validation using two individual siRNAs targeted to USP11 revealed a notable reduction in expression of endogenous ERα target genes in the ZR-75-1 cell line, as quantified using qRT-PCR. Immunoprecipitation of ERα revealed no physical interaction with USP11, however E2 stimulation resulted in translocation of USP11 to the nucleus, suggesting a potential role in E2-induced transcription. Furthermore, USP11 expression was found to be upregulated in the estrogen-independent cell line LCC1 when compared to their parental MCF7 cells. Knockdown of USP11 in LCC1 cells resulted in decreased mRNA expression of a panel of ERα target genes, suggesting a role for USP11 in an estrogen independent setting.

To support the prognostic relevance of USP11, immunohistochemical staining of a breast cancer tissue microarray (n=144) was performed. Kaplan-Meier analysis of this cohort revealed a highly significant association between poor overall survival (OS) (p=0.030) and breast cancer-specific survival (BCSS) (p=0.041). In silico analysis of publically available breast cancer gene expression datasets further supported an association between high USP11 mRNA levels and poor prognosis. We observed a significant correlation between high expression of USP11 mRNA in ER-positive patients and poor distant metastasis-free survival (DMFS) (HR 2, CI 1.37-2.91, p=0.00023). This correlation was also significant in ER-positive patients who had received endocrine therapy only (HR 2.9, CI 1.63-5.15, p=0.00015).

These results suggest a role for USP11 in driving cellular growth and identify USP11 as novel therapeutic target in breast cancer.

Citation Format: Lisa Dwane, Aisling E. O'Connor, Laoighse Mulrane, Annette M. Dirac, Karin Jirstrom, John P. Crown, Rene Bernards, William M. Gallagher, Tríona Ní Chonghaile, Darran P. O'Connor. Functional genomic screening identifies USP11 as a novel regulator of ERα transcription in breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3040. doi:10.1158/1538-7445.AM2017-3040

Addition of gemcitabine to paclitaxel, epirubicin, and cyclophosphamide adjuvant chemotherapy for women with early-stage breast cancer (tAnGo): final 10-year follow-up of an open-label, randomised, phase 3 trial

BACKGROUND

The tAnGo trial was designed to investigate the potential role of gemcitabine when added to anthracycline and taxane-containing adjuvant chemotherapy for early breast cancer. When this study was developed, gemcitabine had shown significant activity in metastatic breast cancer, and there was evidence of a favourable interaction with paclitaxel.

METHODS

tAnGo was an international, open-label, randomised, phase 3 superiority trial that enrolled women aged 18 years or older with newly diagnosed, early-stage breast cancer who had a definite indication for chemotherapy, any nodal status, any hormone receptor status, Eastern Cooperative Oncology Group performance status of 0-1, and adequate bone marrow, hepatic, and renal function. Women were recruited from 127 clinical centres and hospitals in the UK and Ireland, and randomly assigned (1:1) to one of two treatment regimens: epirubicin, cyclophosphamide, and paclitaxel (four cycles of 90 mg/m2 intravenously administered epirubicin and 600 mg/m2 intravenously administered cyclophosphamide on day 1 every 3 weeks, followed by four cycles of 175 mg/m2 paclitaxel as a 3 h infusion on day 1 every 3 weeks) or epirubicin, cyclophosphamide, and paclitaxel plus gemcitabine (the same chemotherapy regimen as the other group, with the addition of 1250 mg/m2 gemcitabine to the paclitaxel cycles, administered intravenously as a 0·5 h infusion on days 1 and 8 every 3 weeks). Patients were randomly assigned by a central computerised deterministic minimisation procedure, with stratification by country, age, radiotherapy intent, nodal status, and oestrogen receptor and HER-2 status. The primary endpoint was disease-free survival and the trial aimed to detect 5% differences in 5-year disease-free survival between the treatment groups. Recruitment completed in 2004 and this is the final, intention-to-treat analysis. This trial is registered with EudraCT (2004-002927-41), ISRCTN (51146252), and ClinicalTrials.gov (NCT00039546).

FINDINGS

Between Aug 22, 2001, and Nov 26, 2004, 3152 patients were enrolled and randomly assigned to epirubicin, cyclophosphamide, paclitaxel, and gemcitabine (gemcitabine group; n=1576) or to epirubicin, cyclophosphamide, and paclitaxel (control group; n=1576). 11 patients (six in the gemcitabine group and five in the control group) were ineligible because of pre-existing metastases and were therefore excluded from the analysis. At this protocol-specified final analysis (median follow-up 10 years [IQR 10-10]), 1087 disease-free survival events and 914 deaths had occurred. Disease-free survival did not differ significantly between the treatment groups at 10 years (65% [63-68] in the gemcitabine group vs 65% [62-67] in the control group), and median disease-free survival was not reached (adjusted hazard ratio 0·97 [95% CI 0·86-1·10], p=0·64). Toxicity, dose intensity, and a detailed safety substudy showed both regimens to be safe, deliverable, and tolerable. Grade 3 and 4 toxicities were reported at expected levels in both groups. The most common were neutropenia (527 [34%] of 1565 patients in the gemcitabine group vs 412 [26%] of 1567 in the control group), myalgia and arthralgia (207 [13%] vs 186 [12%]), fatigue (207 [13%] vs 152 [10%]), infection (202 [13%] vs 141 [9%]), vomiting (143 [9%] vs 108 [7%]), and nausea (132 [8%] vs 102 [7%]).

INTERPRETATION

The addition of gemcitabine to anthracycline and taxane-based adjuvant chemotherapy at this dose and schedule confers no therapeutic advantage in terms of disease-free survival in early breast cancer, although it can cause increased toxicity. Therefore, gemcitabine has not been added to standard adjuvant chemotherapy in breast cancer for any subgroup.

FUNDING

Cancer Research UK core funding for Clinical Trials Unit at the University of Birmingham, Eli Lilly, Bristol-Myers Squibb, and Pfizer.

Incidence of permanent alopecia following adjuvant chemotherapy in women with early stage breast cancer

e21576

Background: Alopecia is one of the most distressing toxicities of adjuvant chemotherapy for patients with breast cancer. Historically, oncologists have reassured patients (pts) that chemotherapy-induced alopecia is temporary, and followed by full hair recovery. More recently there have been troubling reports of permanent alopecia following adjuvant taxanes (Tax). We studied the incidence of long-term hair loss in patients treated on adjuvant trials in our institution. Patients who were enrolled on clinical trials involving Tax (D-Docetaxel, P-Paclitaxel) and/or Anthracyclines (A) were included. Methods: We conducted a telephone interview survey of pts who had completed adjuvant or neo adjuvant A and/or T chemotherapy on clinical trials more than one year before. Ongoing alopecia was graded as 0 (full hair recovery), 1 (mild hair loss) or 2(severe/total). The study was approved by the hospital audit committee. Results: We studied 295 pts who has been treated on 12 studies. Drug exposure: D-260 pts (D nonA-185, D+A-75); A-nonTax-12 pts ; A+P 23 pts. The overall incidence of alopecia was 15% (11% grade 1 and 4% grade 2). For all D the incidence was 15% (12% Grade 1 and 3% Grade 2). For D+A-24% (19% Grade 1 and 5% Grade 2). For D non A the incidence was 13% ( 8% grade 1 and 5% grade 2). For A non T 8% (Grade 2-8%). For PA-13% ( 4% grade 1 and 9% grade 2). For patients receiving D non-A regimens, there were two levels of D exposure, 300mg/m2 (90 pts) or 450 mg/m 2 (95 pts). The incidence of alopecia was significantly D dose dependent: D300- 7% (all grade 1) and D 450-19% (14% grade 1, 5% grade 2) (p = .02 chi2 ). Among the higher dose D group, the companion drug choices carboplatin for HER2 positive, (55 pts) or cyclophosphamide (40 pts) were associated with similar incidences of permanent alopecia (22% v 16%). Conclusions: Permanent alopecia is a common complication of adjuvant chemotherapy. The risk appears to be highest in regimens which contain A and Tax, but it is also seen in AP and in A non-Tax. For patients receiving D non A, the risk is dose-dependent. Our data set contains few P pts, and does not contain any pts undergoing low dose weekly P. Oncologists should warn all patients undergoing adjuvant therapy of the risk of permanent alopecia.

Efficacy and safety of palbociclib in combination with letrozole as first-line treatment of ER-positive, HER2-negative, advanced breast cancer: expanded analyses of subgroups from the randomized pivotal trial PALOMA-1/TRIO-18

Background

Palbociclib is an oral small-molecule inhibitor of cyclin-dependent kinases 4 and 6. In the randomized, open-label, phase II PALOMA-1/TRIO-18 trial, palbociclib in combination with letrozole improved progression-free survival (PFS) compared with letrozole alone as first-line treatment of estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative, advanced breast cancer (20.2 months versus 10.2 months; hazard ratio (HR) = 0.488, 95 % confidence interval (CI) 0.319–0.748; one-sided p = 0.0004). Grade 3–4 neutropenia was the most common adverse event (AE) in the palbociclib + letrozole arm. We now present efficacy and safety analyses based on several specific patient and tumor characteristics, and present in detail the clinical patterns of neutropenia observed in the palbociclib + letrozole arm of the overall safety population.

Methods

Postmenopausal women (n = 165) with ER+, HER2-negative, advanced breast cancer who had not received any systemic treatment for their advanced disease were randomized 1:1 to receive either palbociclib in combination with letrozole or letrozole alone. Treatment continued until disease progression, unacceptable toxicity, consent withdrawal, or death. The primary endpoint was PFS. We now analyze the difference in PFS for the treatment populations by subgroups, including age, histological type, history of prior neoadjuvant/adjuvant systemic treatment, and sites of distant metastasis, using the Kaplan-Meier method. HR and 95 % CI are derived from a Cox proportional hazards regression model.

Results

A clinically meaningful improvement in median PFS and clinical benefit response (CBR) rate was seen with palbociclib + letrozole in every subgroup evaluated. Grade 3–4 neutropenia was the most common AE with palbociclib + letrozole in all subgroups. Analysis of the frequency of neutropenia by grade during the first six cycles of treatment showed that there was a downward trend in Grade 3–4 neutropenia over time. Among those who experienced Grade 3–4 neutropenia, 71.7 % had no overlapping infections of any grade and none had overlapping Grade 3–4 infections.

Conclusion

The magnitude of clinical benefit seen with the addition of palbociclib to letrozole in improving both median PFS and CBR rate is consistent in nearly all subgroups analyzed, and consistent with that seen in the overall study population. The safety profile of the combination treatment in all subgroups was also comparable to that in the overall safety population of the study.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-016-0721-5) contains supplementary material, which is available to authorized users.

Impact of palbociclib plus letrozole on pain severity and pain interference with daily activities in patients with estrogen receptor-positive/human epidermal growth factor receptor 2-negative advanced breast cancer as first-line treatment

Background Palbociclib is a recently approved drug for use in combination with letrozole as initial endocrine-based therapy for the treatment of postmenopausal women with advanced estrogen receptor-positive/human epidermal growth factor receptor 2-negative (ER+/HER2-) breast cancer. This report assesses the impact of palbociclib in combination with letrozole versus letrozole alone on patient-reported outcomes of pain. Methods Palbociclib was evaluated in an open-label, randomized, phase II study (PALOMA-1/TRIO-18) among postmenopausal women with advanced ER+/HER2- breast cancer who had not received prior systemic treatment for their advanced disease. Patients received continuous oral letrozole 2.5 mg daily alone or the same letrozole dose and schedule plus oral palbociclib 125 mg, given once daily for 3 weeks followed by 1 week off over repeated 28-day cycles. The primary study endpoint was investigator-assessed progression-free survival in the intent-to-treat population, and these results have recently been published (Finn et al., Lancet Oncol 2015;16:25-35). One of the key secondary endpoints was the evaluation of pain, as measured using the Brief Pain Inventory (BPI) patient-reported outcome tool. The BPI was administered at baseline and on day 1 of every cycle thereafter until disease progression and/or treatment discontinuation. Clinical trial registration This study is registered with ClinicalTrials.gov (NCT00721409). Results There were no statistically significant differences in Pain Severity or Pain Interference scores of the BPI between the two treatment groups for the overall population or among those with any bone disease at baseline. A limitation of the study is that results were not adjusted for the concomitant use of opioids or other medications used to control pain. Conclusions The addition of palbociclib to letrozole was associated with increased efficacy without negatively impacting pain severity or pain interference with daily activities.

Abstract P4-13-02: Treatment patterns of post-disease progression in the PALOMA-1/TRIO-18 trial

Background

Palbociclib (P) is an oral CDK4/6 inhibitor. In PALOMA-1/TRIO-18, a randomized phase 2 trial, addition of P to letrozole (L) significantly prolonged progression-free survival (PFS) (20 mo with P+L vs 10 mo with L alone; HR = 0.488, P=0.0004; Finn et al, Lancet Oncol, 2015) in postmenopausal women with estrogen-receptor-positive (ER+), HER2-negative advanced breast cancer (ABC) in the first-line setting. At the time of final PFS analysis, overall survival (OS) was immature.

Objectives

It is clinically important to understand whether patients (pts) benefit from standard of care endocrine therapy (ET) after they progressed on P+L as first-line treatment for ABC. We report patterns of post-progression treatment in the next line of therapy immediately following participation in the PALOMA-1 trial.

Methods

Postmenopausal women with ER+ and HER2- ABC who had not received any treatment for their advanced disease were randomized to receive P+L (N = 84) or L alone (N = 81) in the first-line setting. The primary endpoint was investigator-assessed PFS. Tumor assessment was performed every 8 weeks. Post-progression treatment data was captured and analyzed.

Results

As of the data cut-off (Nov 29, 2013), 40 progression events had occurred in the P+L arm and 59 in the L alone arm. 50% of pts in the P+L arm vs. 64% in the L alone arm received ET after progression on study treatment. 60% of pts in the P+L arm vs. 66% in the L alone arm received chemotherapy (CT) after progression on study treatment. The time to 1st subsequent ET/ CT after progression on study treatment, duration of 1st subsequent ET/CT, and choice of 1st subsequent ET/ CT are shown in Table 1.

Table 1 P + LL N=84N=81Patients (pts) with Disease Progression, NN (%)a40 (47.6)59 (72.8)Pts who received subsequent Endocrine Therapy (ET) after progression on study treatment, n(%)b20 (50.0)*38 (64.4)*Time from randomization to 1st subsequent ET (days), median (range)465.5 (239-1100)368.5 (65-1102)Duration of 1st subsequent ET (days), median (range)**153 (24-592)151 (16-1135)Choice of 1st subsequent ET, n(%)bFulvestrant9 (22.5)15 (25.4)Exemestane6 (15.0)9 (15.3)Medroxyprogesterone4 (10.0)1 (1.7)Letrozole1 (2.5)5 (8.5)Tamoxifen08 (13.6)Pts who received subsequent Chemotherapy (CT) after progression on study treatment, n(%)b24 (60.0)*39 (66.1)*Time from randomization to 1st subsequent CT (days), median (range)388.5 (69-918)281 (46-1013)Duration of 1st subsequent CT (days), median (range)**92 (1-457)120 (1-1143)Choice of 1st subsequent CT, n(%)bCapecitabine1 (2.5)10 (17.0)Mitoxantrone13 (32.5)1 (1.7)Paclitaxel013 (22.0)Other10 (25)15 (25.4)apercentages are based on N as denominator; bpercentages based on NN as denominator; *some patients had both ET and CT after progression; **calculated as treatment stop date minus treatment start date +1; if treatment was ongoing at time of data cut-off, stop date was imputed as Nov 29, 2013.

Conclusions

P+L delayed the time to ET/CT as compared to L alone. Pts benefited from standard of care ET/CT after they progressed on P+L as first-line treatment for ABC as demonstrated by the length of time on subsequent therapies; no difference was observed from the L alone arm.

Clinical Trial Information: NCT00721409

Funding Source: Pfizer.

Citation Format: Finn RS, Crown JP, Ettl J, Pinter T, Thummala A, Shparyk Y, Patel R, Randolph S, Kim S, Huang X, Nadanaciva S, Huang Bartlett C, Slamon DJ. Treatment patterns of post-disease progression in the PALOMA-1/TRIO-18 trial. [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 P4-13-02.

High-throughput oncogene mutation profiling shows demographic differences in BRAF mutation rates among melanoma patients

Because of advances in targeted therapies, the clinical evaluation of cutaneous melanoma is increasingly based on a combination of traditional histopathology and molecular pathology. Therefore, it is necessary to expand our knowledge of the molecular events that accompany the development and progression of melanoma to optimize clinical management. The central objective of this study was to increase our knowledge of the mutational events that complement melanoma progression. High-throughput genotyping was adapted to query 159 known single nucleotide mutations in 33 cancer-related genes across two melanoma cohorts from Ireland (n=94) and Belgium (n=60). Results were correlated with various clinicopathological characteristics. A total of 23 mutations in 12 genes were identified, that is--BRAF, NRAS, MET, PHLPP2, PIK3R1, IDH1, KIT, STK11, CTNNB1, JAK2, ALK, and GNAS. Unexpectedly, we discovered significant differences in BRAF, MET, and PIK3R1 mutations between the cohorts. That is, cases from Ireland showed significantly lower (P<0.001) BRAF(V600E) mutation rates (19%) compared with the mutation frequency observed in Belgian patients (43%). Moreover, MET mutations were detected in 12% of Irish cases, whereas none of the Belgian patients harbored these mutations, and Irish patients significantly more often (P=0.027) had PIK3R1-mutant (33%) melanoma versus 17% of Belgian cases. The low incidence of BRAF(V600E)(-) mutant melanoma among Irish patients was confirmed in five independent Irish cohorts, and in total, only 165 of 689 (24%) Irish cases carried mutant BRAF(V600E). Together, our data show that melanoma-driving mutations vary by demographic area, which has important implications for the clinical management of this disease.

The cyclin-dependent kinase 4/6 inhibitor palbociclib in combination with letrozole versus letrozole alone as first-line treatment of oestrogen receptor-positive, HER2-negative, advanced breast cancer (PALOMA-1/TRIO-18): a randomised phase 2 study

BACKGROUND

Palbociclib (PD-0332991) is an oral, small-molecule inhibitor of cyclin-dependent kinases (CDKs) 4 and 6 with preclinical evidence of growth-inhibitory activity in oestrogen receptor-positive breast cancer cells and synergy with anti-oestrogens. We aimed to assess the safety and efficacy of palbociclib in combination with letrozole as first-line treatment of patients with advanced, oestrogen receptor-positive, HER2-negative breast cancer.

METHODS

In this open-label, randomised phase 2 study, postmenopausal women with advanced oestrogen receptor-positive and HER2-negative breast cancer who had not received any systemic treatment for their advanced disease were eligible to participate. Patients were enrolled in two separate cohorts that accrued sequentially: in cohort 1, patients were enrolled on the basis of their oestrogen receptor-positive and HER2-negative biomarker status alone, whereas in cohort 2 they were also required to have cancers with amplification of cyclin D1 (CCND1), loss of p16 (INK4A or CDKN2A), or both. In both cohorts, patients were randomly assigned 1:1 via an interactive web-based randomisation system, stratified by disease site and disease-free interval, to receive continuous oral letrozole 2.5 mg daily or continuous oral letrozole 2.5 mg daily plus oral palbociclib 125 mg, given once daily for 3 weeks followed by 1 week off over 28-day cycles. The primary endpoint was investigator-assessed progression-free survival in the intention-to-treat population. Accrual to cohort 2 was stopped after an unplanned interim analysis of cohort 1 and the statistical analysis plan for the primary endpoint was amended to a combined analysis of cohorts 1 and 2 (instead of cohort 2 alone). The study is ongoing but closed to accrual; these are the results of the final analysis of progression-free survival. The study is registered with the ClinicalTrials.gov, number NCT00721409.

FINDINGS

Between Dec 22, 2009, and May 12, 2012, we randomly assigned 165 patients, 84 to palbociclib plus letrozole and 81 to letrozole alone. At the time of the final analysis for progression-free survival (median follow-up 29.6 months [95% CI 27.9-36.0] for the palbociclib plus letrozole group and 27.9 months [25.5-31.1] for the letrozole group), 41 progression-free survival events had occurred in the palbociclib plus letrozole group and 59 in the letrozole group. Median progression-free survival was 10.2 months (95% CI 5.7-12.6) for the letrozole group and 20.2 months (13.8-27.5) for the palbociclib plus letrozole group (HR 0.488, 95% CI 0.319-0.748; one-sided p=0.0004). In cohort 1 (n=66), median progression-free survival was 5.7 months (2.6-10.5) for the letrozole group and 26.1 months (11.2-not estimable) for the palbociclib plus letrozole group (HR 0.299, 0.156-0.572; one-sided p<0.0001); in cohort 2 (n=99), median progression-free survival was 11.1 months (7.1-16.4) for the letrozole group and 18.1 months (13.1-27.5) for the palbociclib plus letrozole group (HR 0.508, 0.303-0.853; one-sided p=0.0046). Grade 3-4 neutropenia was reported in 45 (54%) of 83 patients in the palbociclib plus letrozole group versus one (1%) of 77 patients in the letrozole group, leucopenia in 16 (19%) versus none, and fatigue in four (4%) versus one (1%). Serious adverse events that occurred in more than one patient in the palbociclib plus letrozole group were pulmonary embolism (three [4%] patients), back pain (two [2%]), and diarrhoea (two [2%]). No cases of febrile neutropenia or neutropenia-related infections were reported during the study. 11 (13%) patients in the palbociclib plus letrozole group and two (2%) in the letrozole group discontinued the study because of adverse events.

INTERPRETATION

The addition of palbociclib to letrozole in this phase 2 study significantly improved progression-free survival in women with advanced oestrogen receptor-positive and HER2-negative breast cancer. A phase 3 trial is currently underway.

FUNDING

Pfizer.

Peroxiredoxin-1 protects estrogen receptor α from oxidative stress-induced suppression and is a protein biomarker of favorable prognosis in breast cancer

INTRODUCTION

Peroxiredoxin-1 (PRDX1) is a multifunctional protein, acting as a hydrogen peroxide (H2O2) scavenger, molecular chaperone and immune modulator. Although differential PRDX1 expression has been described in many tumors, the potential role of PRDX1 in breast cancer remains highly ambiguous. Using a comprehensive antibody-based proteomics approach, we interrogated PRDX1 protein as a putative biomarker in estrogen receptor (ER)-positive breast cancer.

METHODS

An anti-PRDX1 antibody was validated in breast cancer cell lines using immunoblotting, immunohistochemistry and reverse phase protein array (RPPA) technology. PRDX1 protein expression was evaluated in two independent breast cancer cohorts, represented on a screening RPPA (n = 712) and a validation tissue microarray (n = 498). In vitro assays were performed exploring the functional contribution of PRDX1, with oxidative stress conditions mimicked via treatment with H2O2, peroxynitrite, or adenanthin, a PRDX1/2 inhibitor.

RESULTS

In ER-positive cases, high PRDX1 protein expression is a biomarker of improved prognosis across both cohorts. In the validation cohort, high PRDX1 expression was an independent predictor of improved relapse-free survival (hazard ratio (HR) = 0.62, 95% confidence interval (CI) = 0.40 to 0.96, P = 0.032), breast cancer-specific survival (HR = 0.44, 95% CI = 0.24 to 0.79, P = 0.006) and overall survival (HR = 0.61, 95% CI = 0.44 to 0.85, P = 0.004). RPPA screening of cancer signaling proteins showed that ERα protein was upregulated in PRDX1 high tumors. Exogenous H2O2 treatment decreased ERα protein levels in ER-positive cells. PRDX1 knockdown further sensitized cells to H2O2- and peroxynitrite-mediated effects, whilst PRDX1 overexpression protected against this response. Inhibition of PRDX1/2 antioxidant activity with adenanthin dramatically reduced ERα levels in breast cancer cells.

CONCLUSIONS

PRDX1 is shown to be an independent predictor of improved outcomes in ER-positive breast cancer. Through its antioxidant function, PRDX1 may prevent oxidative stress-mediated ERα loss, thereby potentially contributing to maintenance of an ER-positive phenotype in mammary tumors. These results for the first time imply a close connection between biological activity of PRDX1 and regulation of estrogen-mediated signaling in breast cancer.

Abstract B049: An integrated approach to study miRNA involvement in anti-endocrine resistance in breast cancer

Resistance to endocrine-directed therapy represents a significant problem in the management of breast cancer, with a substantial number of estrogen receptor (ER)-positive patients experiencing relapse post treatment. Recently, microRNAs (miRNAs) have been implicated not only in the initiation and progression of cancer, but also in the development of resistance to therapy. To further investigate the role of miRNAs in anti-endocrine resistance in breast cancer, TaqMan Human MicroRNA Arrays (Applied Biosystems) were used to profile global expression of 667 miRNAs from a cell line series developed from MCF7 cells. This series consisted of parental ER-positive MCF7 cells, estrogen-independent anti-estrogen sensitive LCC1 cells and anti-estrogen resistant LCC9 cells obtained from the stepwise selection of LCC1 cells against increasing concentrations of fulvestrant.

Using an in-house developed Java (v6.0) software application, transcriptomic data from these cell lines was integrated with miRNA expression data together with a miRNA-mRNA target site prediction database (compiled from TargetScan) to highlight networks of related genes/miRNAs. Gene Ontology (GO) categories were retrieved from DAVID. Hierarchical clustering produced two distinct clusters of genes which were negatively correlated with two groups of miRNAs differentially expressed &gt;2 fold between the three cell lines. GO analysis revealed that Cluster 1 (2,146 genes negatively correlated with 37 miRNAs) was significantly associated with protein catabolism, chromatin modification and changes in Wnt, TGFβ and Insulin signaling. Cluster 2 (1,289 genes negatively correlated with 7 miRNAs) was associated with neuron differentiation and cell motion as well as changes to the ErbB and mTOR signaling pathways. Both clusters were associated significantly with changes in MAPK signaling.

Four miRNAs (miR-20b, -28-5p, -28-3p and -31) were selected for further analysis owing to their increased expression in anti-endocrine resistant LCC9 cells relative to both MCF7 and LCC1 lines. Interestingly, ectopic expression of miR-31, but not miR-20b or -28, conferred resistance to tamoxifen treatment in both MCF7 and LCC1 cells (p&lt;0.05). Furthermore, GO analysis of genes negatively correlated with miR-31 revealed changes in the ErbB and mTOR signaling pathways, both of which have been widely associated with anti-endocrine resistance in breast cancer.

Citation Format: Laoighse Mulrane, Marta Terrile, Kenneth Bryan, Raymond L. Stallings, Robert Clarke, John P. Crown, William M. Gallagher, Darran P. O'Connor. An integrated approach to study miRNA involvement in anti-endocrine resistance in breast cancer. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Breast Cancer Research: Genetics, Biology, and Clinical Applications; Oct 3-6, 2013; San Diego, CA. Philadelphia (PA): AACR; Mol Cancer Res 2013;11(10 Suppl):Abstract nr B049.

Phase III trial of sunitinib in combination with capecitabine versus capecitabine monotherapy for the treatment of patients with pretreated metastatic breast cancer

PURPOSE

Metastatic breast cancer (MBC) remains an incurable illness in the majority of cases, despite major therapeutic advances. This may be related to the ability of breast tumors to induce neoangiogenesis, even in the face of cytotoxic chemotherapy. Sunitinib, an inhibitor of key molecules involved in neoangiogenesis, has an established role in the treatment of metastatic renal cell and other cancers and demonstrated activity in a phase II trial in MBC. We performed a randomized phase III trial comparing sunitinib plus capecitabine (2,000 mg/m2) with single-agent capecitabine (2,500 mg/m2) in patients with heavily pretreated MBC.

PATIENTS AND METHODS

Eligibility criteria included MBC, prior therapy with anthracyclines and taxanes, one or two prior chemotherapy regimens for metastatic disease or early relapse after a taxane plus anthracycline adjuvant regimen, and adequate organ function and performance status. The primary end point was progression-free survival, for which the study had 90% power to detect a 50% improvement (from 4 to 6 months).

RESULTS

A total of 442 patients were randomly assigned. Progression-free survival was not significantly different between the treatment arms, with medians of 5.5 months (95% CI, 4.5 to 6.0) for the sunitinib plus capecitabine arm and 5.9 months (95% CI, 5.4 to 7.6) for the capecitabine monotherapy arm (hazard ratio, 1.22; 95% CI, 0.95 to 1.58; one-sided P = .941). There were no significant differences in response rate or overall survival. Toxicity, except for hand-foot syndrome, was more severe in the combination arm.

CONCLUSION

The addition of sunitinib to capecitabine does not improve the clinical outcome of patients with MBC pretreated with anthracyclines and taxanes.

Abstract P4-09-06: miR-187 is an independent prognostic factor in lymph node-positive breast cancer patients

Purpose: MicroRNAs (miRNAs) involved in cancer progression have now become the focus of much attention as they represent a new class of biomarkers and potential drug targets. Here, we describe an integrated bioinformatics, functional analysis and translational pathology approach for the identification of novel miRNAs involved in breast cancer progression.

Experimental Design

Differential gene expression can, in part, be attributed to the activity of specific miRNAs. Given a database of miRNA binding site motifs and gene expression levels determined by transcriptomic profiling, correspondence analysis, between group analysis and co-inertia analysis can be combined to produce a ranked list of miRNAs associated with a specific gene signature and phenotype. Here, using two independent breast cancer cohorts, this approach was employed to produce a ranked list of miRNAs associated with disease progression. Functional studies were subsequently carried out in MCF7 cells assessing for alterations in growth, tumorigenicity and agressiveness and miRNA expression was evaluated in two cohorts of breast cancer patients by locked nucleic acid in situ hybridisation on tissue microarrays.

Results: CIA identified miR-187 as a key miRNA associated with poor outcome in breast cancer.

Ectopic expression of miR-187 in MCF7 cells resulted in a more aggressive phenotype (evidenced by increased anchorage-independent growth, migratory and invasive potential).

In a test cohort (n = 117) breast cancer patients, high expression of miR-187 was associated with a trend towards reduced breast cancer-specific survival (BCSS) (p = 0.058), and a significant association with reduced BCSS in lymph node-positive patients (p = 0.036). In a validation cohort (n = 470), high miR-187 was significantly associated with reduced BCSS in the entire cohort (p = 0.021) and, again, in lymph node-positive patients (p = 0.012).

Multivariate cox regression analysis revealed that miR-187 is an independent prognostic factor in both TMA cohorts (Cohort 1 HR-7.369 (95% CI 2.048–26.509, p = 0.002); Cohort 2 HR-2.798 (95% CI 1.518–5.157, p = 0.001).

Conclusions: miR-187 expression in breast cancer leads to the formation of a more aggressive, invasive phenotype and acts as an independent predictor of outcome.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-09-06.

Abstract OT1-1-06: A phase III randomized study of Paclitaxel and Trastuzumab versus Paclitaxel, Trastuzumab and Lapatinib in first line treatment of HER2 positive metastatic breast cancer

Background: Preclinical studies have shown that dual targeting of the extracellular domain and the kinase domain of HER2 using trastuzumab (H) and lapatinib (L) produces greater growth inhibition than single agent treatment. The combination of trastuzumab and lapatinib has shown improved clinical outcome compared to lapatinib alone in the pre-treated metastatic setting (EGF104900), and compared to trastuzumab in the neo-adjuvant setting (Neo-Altto). This international phase III randomised trial will compare the efficacy of trastuzumab and paclitaxel (T) with trastuzumab, paclitaxel and lapatinib in first line treatment of HER2 positive metastatic breast cancer, and will examine potential predictive biomarkers of response to trastuzumab and/or lapatinib.

Study Design and Eligibility: Six hundred patients with invasive HER2 positive (3+ or FISH positive) metastatic breast cancer (measurable disease per RECIST 1.1), who have not received prior systemic therapy for metastatic disease, will be randomised to receive (A) weekly paclitaxel (80 mg/m2, for 3 weeks of a 4 week cycle) plus trastuzumab (8 mg/kg loading dose day 1 and 4mg/kg every 2 weeks) or (B) weekly paclitaxel (80 mg/m2, for 3 weeks of a 4 week cycle) plus trastuzumab (8 mg/kg loading dose day 1 and 4 mg/kg every 2 weeks) plus lapatinib (1,000 mg daily), until disease progression, unacceptable toxicity or consent withdrawal.

Objectives: The primary objective of the study is to compare the efficacy of THL versus TH in first line treatment of metastatic HER2 positive breast cancer. Secondary objectives include: (i) examining the objective tumour response rate and overall survival; (ii) assessing the safety and tolerability of lapatinib when administrated with both paclitaxel and trastuzumab; (iii) examining the effects of the TH regimen versus the THL regimen on health-related quality of life (FACT-B); (iv) examining potential biomarkers in tumour tissue and serum samples; (v) determining if prophylactic loperamide significantly reduces the number of diarrhoea-related adverse events.

Statistical Methods: The expected median progression free survival time for the control arm is 6.9 months based on the trastuzumab plus paclitaxel arm of the phase III trastuzumab plus chemotherapy trial. A total of 600 evaluable patients (and 485 observed events) would be sufficient to detect an increase to 8.9 months in median PFS time for the THL combination, with 80% power and a two sided significance level of 0.05. Progression-free survival will be analysed at nine months after enrolment ends and overall survival will be analysed at 30 months after the end of enrolment. Objective response will be defined as the proportion of patients who receive a complete or partial response as defined by RECIST 1.1.

Accrual: This study will accrue six hundred patients across forty International centres. Countries signed up to participate include Finland, France, Germany, Greece, Iceland, Ireland, Israel, Italy, Netherlands, Norway, Poland, Portugal, Switzerland and Spain. The study opened to accrual in Ireland Feb 12 and six patients have been accrued to date.

Funding: Trial supported by GlaxoSmithKline. Lapatinib kindly supplied by GlaxoSmithKline.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr OT1-1-06.

Abstract S1-6: Results of a randomized phase 2 study of PD 0332991, a cyclin-dependent kinase (CDK) 4/6 inhibitor, in combination with letrozole vs letrozole alone for first-line treatment of ER+/HER2− advanced breast cancer (BC)

Background: PD 0332991, a selective inhibitor of CDK 4/6, prevents cellular DNA synthesis by blocking cell cycle progression. Preclinical studies in a BC cell line panel identified the luminal ER subtype, elevated expression of cyclin D1 and Rb protein, and reduced p16 expression as being associated with sensitivity to PD 0332991 (Finn et al. 2009). Synergistic activity was also observed in vitro when combined with tamoxifen. After determination of the recommended phase 2 dose in combination with letrozole (letrozole 2.5 mg QD plus PD 0332991 125 mg QD on Schedule 3/1), a randomized phase 2 study comparing letrozole alone (L) to letrozole plus PD 0332991 (L+P) was initiated.

Methods: The phase 2 portion of the study was designed as a two-part study; Part 1 enrolled post- menopausal women with ER+/HER2− advanced BC; Part 2 in addition to ER+/HER2− as eligibility criteria, screened for CCND1 amplification and/or loss of p16 by FISH. The primary endpoint is progression-free survival (PFS); secondary endpoints include response rate, overall survival, safety, and correlative biomarker studies. In both parts, post-menopausal women with ER+/HER2− advanced BC were randomized 1:1 to receive letrozole either with or without PD 0332991. Pts continue on assigned study treatment until disease progression, unacceptable toxicity, or consent withdrawal, and are followed for tumor assessments every 2 months.

Results: 66 pts were randomized in Part 1 and 99 pts in Part 2. Preliminary results from Part 1 of this study have been previously reported (IMPAKT Breast Cancer Conference, Abstract #292, Finn et al. May 2012) demonstrating a significant improvement in median PFS in the L+P vs. L arm (HR = 0.35; 95% CI, 0.17 to 0.72; p = 0.006). With the additional 99 pts randomized in Part 2 (N = 165), the statistically significant improvement in median PFS (26.2 vs. 7.5 months, respectively) continues to be observed with a HR=0.32 (95% CI, 0.19 to 0.56) with p &lt;0.001. The response rate for the L+P arm (n = 84) was 31% vs. 26% for the L arm (n = 81) and the clinical benefit rate was 68% vs. 44%, respectively. The most commonly reported treatment-related AEs in the combination arm were neutropenia, leukopenia, anemia, and fatigue. The updated results from the combined Part 1 and Part 2 group will be presented in December 2012.

Conclusions: The combination of PD 0332991 and letrozole is well tolerated and shows encouraging clinical benefit, confirming the sensitivity of ER+ BC to PD 0332991 observed in preclinical models. A phase 3 trial in this setting will commence in 2013.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr S1-6.

P1-17-05: Preliminary Results of a Randomized Phase 2 Study of PD 0332991, a Cyclin-Dependent Kinase (CDK) 4/6 Inhibitor, in Combination with Letrozole for First-Line Treatment of Patients (pts) with Post-Menopausal, ER+, HER2−Negative (HER2–) Advanced Breast Cancer

Background: PD 0332991 is an orally bioavailable selective inhibitor of CDK 4/6 and prevents cellular DNA synthesis by prohibiting progression of the cell cycle from G1 into the S phase. Preclinical evaluations suggest that reduction in CDKN2A (p16) expression and cyclin D1 (CCND1) overexpression confer susceptibility to PD 0332991 (Finn 2009). In addition, PD 0332991 was synergistic in combination with tamoxifen in vitro in ER+ human breast cancer cell lines. Based on these observations, a phase 1/2 study in combination with letrozole as first-line therapy for advanced ER+ post-menopausal breast cancer was initiated. The phase 1 part of the study (completed) determined the recommended phase 2 dose to be PD 0332991 125 mg QD on Schedule 3/1 (3 weeks on treatment followed by 1-week off treatment) in combination with letrozole 2.5 mg QD. The combination was generally well tolerated and encouraging antitumor activity was observed. We present preliminary data from the randomized Phase 2 portion comparing letrozole alone to letrozole plus PD 0332991.

Methods: The Phase 2 portion of the study is designed as a two-part study; we present data from Part 1. In both parts, eligible patients are randomized 1:1 to letrozole 2.5 mg QD alone (control) or PD 0332991 125 mg QD on schedule 3/1 and letrozole 2.5 mg QD (treatment, tx). Part 1enrolled post-menopausal women with ER+, HER2− cancer using only ER+, HER2−as a selection criteria. Part 2 is now enrolling post-menopausal women with ER+, HER2− breast cancer with CCND1 amplification and/or loss of p16 by FISH (target N=150). The primary endpoint is progression-free survival (PFS); secondary endpoints include overall survival, response rate, safety, and correlative studies. Pts are stratified for disease site and length from prior adjuvant therapy. Pts continue assigned study treatment until disease progression, unacceptable toxicity, or consent withdrawal and are followed every 2 months to assess disease status. Tumor tissue was required for participation.

Results: 66 patients have been randomized in Part 1. At the time of data cut-off (April 2011) median duration of treatment is 20 (range 4–64) wks for control and 27 (2-59) wks for tx. Dose reductions occurred in 9 pts on the tx arm and none on the control arm. There are no complete responses. The number of partial responses for pts with measurable disease are similar between arms (4/22 control vs 5/24 in tx). The number of pts with stable disease&gt; 24 weeks was higher in the tx arm (5 vs 8). The number of pts with best response of progressive disease is lower in the treatment arm (2 vs 6). PFS data are immature. Twelve pts remain on control vs. 21 on tx. As in the Phase I portion of the study, the most common treatment-related AEs were neutropenia and leucopenia without febrile neutropenia. Biomarker studies for CCND1 amplification, p16 loss, RB status, and Ki67 are ongoing.

Conclusion: The combination of PD 0332991 and letrozole is well tolerated as first-line treatment of ER+, HER2− post-menopausal breast cancer. Updated efficacy data and biomarker data will be presented.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-17-05.

The cocaine- and amphetamine-regulated transcript mediates ligand-independent activation of ERα, and is an independent prognostic factor in node-negative breast cancer

Personalized medicine requires the identification of unambiguous prognostic and predictive biomarkers to inform therapeutic decisions. Within this context, the management of lymph node-negative breast cancer is the subject of much debate with particular emphasis on the requirement for adjuvant chemotherapy. The identification of prognostic and predictive biomarkers in this group of patients is crucial. Here, we demonstrate by tissue microarray and automated image analysis that the cocaine- and amphetamine-regulated transcript (CART) is expressed in primary and metastatic breast cancer and is an independent poor prognostic factor in estrogen receptor (ER)-positive, lymph node-negative tumors in two separate breast cancer cohorts (n=690; P=0.002, 0.013). We also show that CART increases the transcriptional activity of ERα in a ligand-independent manner via the mitogen-activated protein kinase pathway and that CART stimulates an autocrine/paracrine loop within tumor cells to amplify the CART signal. Additionally, we demonstrate that CART expression in ER-positive breast cancer cell lines protects against tamoxifen-mediated cell death and that high CART expression predicts disease outcome in tamoxifen-treated patients in vivo in three independent breast cancer cohorts. We believe that CART profiling will help facilitate stratification of lymph node-negative breast cancer patients into high- and low-risk categories and allow for the personalization of therapy.

High-dose chemotherapy with autologous stem-cell support as adjuvant therapy in breast cancer: overview of 15 randomized trials

PURPOSE

Adjuvant high-dose chemotherapy (HDC) with autologous hematopoietic stem-cell transplantation (AHST) for high-risk primary breast cancer has not been shown to prolong survival. Individual trials have had limited power to show overall benefit or benefits within subsets.

METHODS

We assembled individual patient data from 15 randomized trials that compared HDC versus control therapy without stem-cell support. Prospectively defined primary end points were relapse-free survival (RFS) and overall survival (OS). We compared the effect of HDC versus control by using log-rank tests and proportional hazards regression, and we adjusted for clinically relevant covariates. Subset analyses were by age, number of positive lymph nodes, tumor size, histology, hormone receptor (HmR) status, and human epidermal growth factor receptor 2 (HER2) status.

RESULTS

Of 6,210 total patients (n = 3,118, HDC; n = 3,092 control), the median age was 46 years; 69% were premenopausal, 29% were postmenopausal, and 2% were unknown menopausal status; 49.5% were HmR positive; 33.5% were HmR negative, and 17% were unknown HmR status. The median follow-up was 6 years. After analysis was adjusted for covariates, HDC was found to prolong relapse-free survival (RFS; hazard ratio [HR], 0.87; 95% CI, 0.81 to 0.93; P < .001) but not overall survival (OS; HR, 0.94; 95% CI, 0.87 to 1.02; P = .13). For OS, no covariates had statistically significant interactions with treatment effect, and no subsets evinced a significant effect of HDC. Younger patients had a significantly better RFS on HDC than did older patients.

CONCLUSION

Adjuvant HDC with AHST prolonged RFS in high-risk primary breast cancer compared with control, but this did not translate into a significant OS benefit. Whether HDC benefits patients in the context of targeted therapies is unknown.

High-dose chemotherapy with autologous hematopoietic stem-cell transplantation in metastatic breast cancer: overview of six randomized trials

PURPOSE

High doses of effective chemotherapy are compelling if they can be delivered safely. Substantial interest in supporting high-dose chemotherapy with bone marrow or autologous hematopoietic stem-cell transplantation in the 1980s and 1990s led to the initiation of randomized trials to evaluate its effect in the treatment of metastatic breast cancer.

METHODS

We identified six randomized trials in metastatic breast cancer that evaluated high doses of chemotherapy with transplant support versus a control regimen without stem-cell support. We assembled a single database containing individual patient information from these trials. The primary analysis of overall survival was a log-rank test comparing high dose versus control. We also used Cox proportional hazards regression, adjusting for known covariates. We addressed potential treatment differences within subsets of patients.

RESULTS

The effect of high-dose chemotherapy on overall survival was not statistically different (median, 2.16 v 2.02 years; P = .08). A statistically significant advantage in progression-free survival (median, 0.91 v 0.69 years) did not translate into survival benefit. Subset analyses found little evidence that there are groups of patients who might benefit from high-dose chemotherapy with hematopoietic support.

CONCLUSION

Overall survival of patients with metastatic breast cancer in the six randomized trials was not significantly improved by high-dose chemotherapy; any benefit from high doses was small. No identifiable subset of patients seems to benefit from high-dose chemotherapy.

Abstract P5-10-17: Bevacizumab (Bev) in Combination with Docetaxel (T) and Cyclophosphamide (C) as Adjuvant Treatment (AdjRx) for Patients (pts) with Early Stage (ES) Breast Cancer (BrCa) and Normal HER-2 Status. A Pilot Evaluation

In random assignment trials, the combination of Bev+ chemotherapy has been shown to produce superior response rates and progression free survival compared to chemotherapy alone, providing a rationale for the study of Bev in the AdjRx of pts with ESBrCa. As a principal side effect of Bev is hypertension (HTN), anthracycline-containing (Anth) AdjRx may pose additional cardiovascular risks. The role of Anth in Her2 normal ESBC is uncertain. TC is a standard non-Anth AdjRx. We performed a single arm pilot study to evaluate the feasibility and toxicity of TC+Bev in pts with ESBC in preparation for participation in a random assignment trial. Methods: Eligibility criteria included: ESBC which was HER-2 normal, node-positive or &gt;2 cm and receptor negative, or &gt;3 cm and receptor positive, normal cardiac ejection fraction (EF), no active or uncontrolled cardiovascular disease, normal organ and marrow function. Treatment consisted of four 3 weekly cycles of docetaxel 75 mg/m2 together with cyclophosphamide 600 mg/m2. Patients commenced bevacizumab 15 mg/kg i.v. on day 1, and q 3 weeks to a total of 19 treatments. Pts were monitored clinically, with echocardiograms and with serial estimations of BNP and troponin.

Results: A total of 105 female pts were accrued in 9 ICORG sites between Dec 2008 and June 2010. Ages ranged from 26-86 (median 55). At June 2010, 33 have completed all phases of therapy, 54 are still on treatment. Eighteen pts have been removed from study due to: HTN -7, intestinal perforation -2, withdrew consent-4, proteinuia-1, anaphylaxis-1, infection-3. The perforations occurred at cycles 9 and 19. Neither pt. with perforation had prior abdominal surgery. The median number of cycles achieved by the discontinued pts was 9. HTN requiring Rx occurred in 25 pts. Among 12 with HTN who have completed Bev, 2 are off HTN meds, and 9 are on reducing doses. The median EF at base line was 67%, at 13 cycles (42 pts) 63%, 18 cycles (27 pts) 66%. Six pts had EF drop &gt;10%, in 3 of these EF fell below 50% as last recorded value. There were no episodes of clinical cardiac failure. Troponin and BNP levels were normal in all 57 pts with serial measurements. Thirteen pts required treatment for neutropenia-related infection or for abscess.

Conclusions: The spectrum and frequency of bevacizumab toxicity in our population of healthy adjuvant pts is similar to that reported for pts with metastatic BC and other malignancies. Hypertension is the principal cause of treatment discontinuation, but cardiac toxicity appears to be limited, with this non-anth chemotherapy +Bev. Intestinal perforation can also occur in pts with ESBC. These toxicities can occur in the post chemotherapy phase of Bev therapy. Pts enrolled on random assignment trials of Bev containing AdjRx require careful monitoring for toxicity.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-10-17.

Pooled analysis of diarrhea events in patients with cancer treated with lapatinib

PURPOSE

To characterize diarrhea events in patients with cancer treated with lapatinib as monotherapy or in combination with capecitabine or taxanes.

PATIENTS AND METHODS

Eleven clinical trials (phase I, II, or III) in patients with metastatic cancer were analyzed. Lapatinib was administered at doses ranging from 1,000 to 1,500 mg/day as monotherapy (n = 926) or in combination with capecitabine (n = 198) or taxanes (n = 687). Diarrhea events were characterized based on severity, time to onset, duration, required interventions, and clinical outcomes.

RESULTS

In the pooled analysis of nine studies, diarrhea occurred in 55% of lapatinib-treated patients and 24% of patients not receiving lapatinib. All grade diarrhea occurred in 51% of patients treated with lapatinib monotherapy and 65% treated with lapatinib plus capecitabine. In a separate analysis, 48% of patients treated with lapatinib plus a taxane experienced diarrhea. Overall, most diarrhea events were grade 1/2. Grade 3 events occurred in <10% of patients and grade 4 events were rare (<or=1%). Most diarrhea events resolved with conventional approaches and without dose modification. Approximately 40% of patients treated with lapatinib monotherapy or combination therapy experienced a first diarrhea event within 6 days of treatment initiation, with a median duration of 7-9 days. Lapatinib-containing chemotherapy regimens do not cause severe diarrhea when proactive monitoring and intervention is introduced.

CONCLUSION

Most diarrhea events in lapatinib-treated patients are low grade, requiring infrequent lapatinib dose modification or interruption. Proactive management of diarrhea is crucial to prevent more serious complications in lapatinib-treated patients.

Odynorgasmia

Painful ejaculation ("odynorgasmia") is not well recognized. When it occurs it may indicate the precise site of pathology.

The platinum agents: a role in breast cancer treatment?

Metastatic breast cancer is a partially chemotherapy-sensitive neoplasm. Most chemotherapy groups have activity in this disease, and the most active single drugs are the taxanes, especially docetaxel (Taxotere; Aventis Pharmaceuticals, Inc, Parsippany, NJ), and the anthracyclines. The alkylating agents, antimetabolites, and vinca alkaloids are also widely used. The platinum coordination complexes, which are widely used in oncology, are also active in metastatic breast cancer, but the availability of other drugs that are less toxic and easier to administer has resulted in their having a strictly limited use in this setting. Cisplatin appears to be somewhat more active than carboplatin, but direct comparative studies are lacking. The identification of the prominent activity of the taxanes has led to the investigation of wholly novel non-anthracycline-containing combination regimens, and platinum/taxane doublets appear to be particularly active. More recently, reports that trastuzumab (Herceptin, Genentech, South San Francisco, CA), a novel monoclonal antibody directed against the protein product of the HER2/(neu) oncogene, has a powerful synergistic interaction with docetaxel and with platinum agents have prompted evaluation of the triplet docetaxel/platinum/trastuzumab in the therapy of metastatic breast cancer.

Expanding options in breast cancer

In metastatic breast cancer, docetaxel is the only drug to have shown superior activity to doxorubicin [objective response rates (ORRs) 48 versus 33%] by direct comparison in a randomized trial. Importantly, this greater activity was accompanied by a lower risk of cardiotoxicity. Docetaxel has also proved superior to various combination regimens in patients who had previously failed anthracyclines. In the comparison versus mitomycin C plus vinblastine, survival was significantly prolonged in the docetaxel arm. The combination of paclitaxel with doxorubicin has achieved remarkably high rates of response. However, the combination is cardiotoxic (with the highest response rates reporting an incidence of clinical congestive heart failure in the region of 18%). In comparison, the combination of docetaxel with doxorubicin, while also highly active (ORR > 70%), is relatively non-cardiotoxic (with only one case of clinical congestive heart failure in 96 patients treated). Given that docetaxel appears to be the most active single agent in metastatic breast cancer, there is a compelling case for the drug to be evaluated in the adjuvant setting and such studies are ongoing.

Sequential dose-dense doxorubicin, paclitaxel, and cyclophosphamide for resectable high-risk breast cancer: feasibility and efficacy

PURPOSE

Dose-dense chemotherapy is predicted to be a superior treatment plan. Therefore, we studied dose-dense doxorubicin, paclitaxel, and cyclophosphamide (A-->T-->C) as adjuvant therapy.

METHODS

Patients with resected breast cancer involving four or more ipsilateral axillary lymph nodes were treated with nine cycles of chemotherapy, using 14-day intertreatment intervals. Doses were as follows: doxorubicin 90 mg/m2 x 3, then paclitaxel 250 mg/m2/24 hours x 3, and then cyclophosphamide 3.0 g/m2 x 3; all doses were given with subcutaneous injections of 5 microg/kg granulocyte colony-stimulating factor on days 3 through 10. Amenorrheic patients with hormone receptor-positive tumors received tamoxifen 20 mg/day for 5 years. Patients treated with breast conservation, those with 10 or more positive nodes, and those with tumors larger than 5 cm received radiotherapy.

RESULTS

Between March 1993 and June 1994, we enrolled 42 patients. The median age was 46 years (range, 29 to 63 years), the median number of positive lymph nodes was eight (range, four to 25), and the median tumor size was 3.0 cm (range, 0 to 11.0 cm). The median intertreatment interval was 14 days (range, 13 to 36 days), and the median delivered dose-intensity exceeded 92% of the planned dose-intensity for all three drugs. Hospital admission was required for 29 patients (69%), and 28 patients (67%) required blood product transfusion. No treatment-related deaths or cardiac toxicities occurred. Doxorubicin was dose-reduced in four patients (10%) and paclitaxel was reduced in eight (20%). At a median follow-up from surgery of 48 months (range, 3 to 57 months), nine patients (19%) had relapsed, the actuarial disease-free survival rate was 78% (95% confidence interval, 66% to 92%), and four patients (10%) had died of metastatic disease.

CONCLUSION

Dose-dense sequential adjuvant chemotherapy with doxorubicin, paclitaxel, and cyclophosphamide (A-->T-->C) is feasible and promising. Several ongoing phase III trials are evaluating this approach.

The development of docetaxel (Taxotere) in non-small cell lung cancer--docetaxel in new combinations and new schedules: an overview of ongoing and future developments

Non-small cell lung cancer is the most common cause of cancer death in the western world. Non-small cell lung cancer is modestly sensitive to chemotherapy with a small survival benefit in locally advanced and metastatic disease. Newer agents such as docetaxel are yielding encouraging response rates both as single agents and in combination. A phase I/II study is in progress in our institution to determine the maximum tolerated dose and noncomparative efficacy of the combination of docetaxel (Taxotere; Rhône-Poulenc Rorer, Antony, France), ifosfamide, and cisplatin, with mesna and lenograstim support, in the treatment of patients with advanced non-small cell lung cancer. To date, nine patients have received 37 cycles of treatment at increasing dose levels (no intrapatient dose escalation). Treatment was administered to patients on an inpatient basis every 3 weeks, with lenograstim on days 3 to 10. Dose-limiting toxicity has not occurred at levels I to III (dose level III: docetaxel 75 mg/m2, cisplatin 75 mg/m2, and ifosfamide 3 g/m2). These preliminary results suggest that the combination of docetaxel, ifosfamide, and cisplatin, with lenograstim support, is well tolerated in the doses evaluated. Preliminary efficacy results show a response rate of 67% (six of nine patients). The study continues to determine the maximum tolerated dose of this regimen in preparation for a phase II evaluation.

Resolution of paraneoplastic bile duct paucity following successful treatment of Hodgkin's disease

We report the case of a 21-year-old woman who developed severe adult onset ductopenia in association with Hodgkin's lymphoma. Chemotherapy resulted in a remission of her Hodgkin's disease (HD) and significant improvement in liver function with resolution of the hepatic and biliary duct histological abnormalities, a therapeutic success not previously described in the literature.

Dose escalation of paclitaxel with high-dose carboplatin using peripheral blood progenitor cell support in patients with advanced ovarian cancer

A phase I study of escalating doses of paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) given in combination with high-dose carboplatin was conducted to identify the antitumor efficacy and maximum tolerated dose of paclitaxel in patients who had received sequential cycles of paclitaxel/cyclophosphamide as prior treatment for ovarian carcinoma. Eighteen patients with advanced ovarian cancer were treated in this study. Induction therapy consisted of two cycles of cyclophosphamide 3.0 g/m2 plus high-dose paclitaxel 300 mg/m2 plus filgrastim and leukapheresis to harvest peripheral blood progenitor cells, followed by four courses of rapidly cycled high-dose carboplatin with planned dose escalation of paclitaxel (150, 200, 250, and 300 mg/m2) rescued with peripheral blood progenitor cells. The study was amended after accrual of 11 patients, and the remaining seven patients received a single cycle of induction therapy with paclitaxel/cyclophosphamide, followed by four courses of rapidly cycled high-dose carboplatin with planned dose escalation of paclitaxel through levels 200 and 250 mg/m2. All 18 patients have completed therapy. Of the 15 who are evaluable for response, the pathologic complete response was 33% (five of 15 patients). The administration of escalating doses of paclitaxel in combination with high-dose carboplatin following sequential cycles of paclitaxel/cyclophosphamide induction resulted in significant nonhematopoietic toxicity. Induction with a single cycle of paclitaxel/cyclophosphamide resulted in excellent progenitor cell mobilization, and significantly ameliorated the toxicity of this approach. The response rates thus far obtained are promising and warrant further evaluation.

Phase II and pharmacologic study of docetaxel as initial chemotherapy for metastatic breast cancer

PURPOSE

Because docetaxel (Taxotere, RP 56976; Rhone-Poulenc Rorer, Antony, France) appeared to be active against breast cancer in phase I trials, we performed this phase II study.

PATIENTS AND METHODS

Thirty-seven patients with measurable disease were enrolled. Only prior hormone therapy was allowed, as was adjuvant chemotherapy completed > or = 12 months earlier. Docetaxel 100 mg/m2 was administered over 1 hour every 21 days. Diphenhydramine hydrochloride and/or corticosteroid premedication was added after hypersensitivity-like reactions (HSRs) were seen in two of the first six patients. Pharmacokinetic studies were performed during cycle 1 for correlation with toxicity.

RESULTS

Thirty-seven patients were assessable. Nineteen (51%) required dose reductions, usually for neutropenic fever. The median nadir WBC count was 1.4 x 10(3)/microL. HSRs were noted in 20 patients (54%). At a median cumulative dose of 297 mg/m2 (range, 99.6 to 424.5 mg/m2), 30 patients (81%) developed fluid retention, for which 11 (30%) subsequently stopped treatment. The first-cycle plasma area under the concentration-time curve (AUC) did not correlate with toxicity, although an ineligible patient with hepatic metastases (pretreatment bilirubin level 1.8 mg/dL) had an elevated AUC and died of toxicity. Responses were seen at all sites. On an intent-to-treat basis, there were two (5%) complete responses (CRs) and 18 (49%) partial responses (PRs). The overall response proportion (CRs plus PRs) was 54% (95% confidence interval, 37% to 71%). The median time to response was 12 weeks (range, 3 to 15) and the median duration was 26 weeks (range, 10 to 58+).

CONCLUSION

Docetaxel is active for metastatic breast cancer. Neutropenia and fluid retention are dose-limiting. The AUC did not predict toxicity, but caution is warranted when treating patients with liver dysfunction. An understanding of the pathophysiology of the fluid retention may facilitate prevention. Frequent HSR may warrant prophylactic premedication.

Paclitaxel as second and subsequent therapy for metastatic breast cancer: activity independent of prior anthracycline response

PURPOSE

Two phase II clinical trials were performed to determine efficacy and tolerability of paclitaxel (Taxol; Bristol-Myers Squibb Co, Wallingford, CT) and granulocyte colony-stimulating factor ([G-CSF] Neupogen; Amgen, Inc, Thousand Oaks, CA) as second or subsequent therapy for metastatic breast cancer.

PATIENTS AND METHODS

Paclitaxel plus G-CSF was administered as a second stage IV regimen to 25 patients with metastatic breast cancer at a dose of 250 mg/m2 intravenously over 24 hours. Fifty-two patients received paclitoxel plus G-CSF at 200 mg/m2 as a third or subsequent regimen (no restriction on number of prior regimens or on prior high-dose chemotherapy). All patients had received prior anthracycline treatment, and ultimately had progressive bidimensionally measurable disease.

RESULTS

Twenty-five of 76 patients (32.8%) had a major objective response (95% confidence interval [CI], 14% to 37%). The median duration of response was 7 months (range, 1 to 20+). Responses were as likely in patients with disease demonstrated to be unresponsive to anthracycline, ie, de novo resistance (11 of 37, or 30%) as in those with disease that once exhibited anthracycline sensitivity, ie, acquired resistance, (10 of 31, or 32%). G-CSF administration was associated with febrile neutropenic episodes in 36 of 402 cycles (9%) in 16 of 76 patients (21%).

CONCLUSION

Paclitaxel's clinically significant activity against metastatic breast cancer extends to patients with many prior chemotherapy regimens. The lack of impact of prior doxorubicin therapy on the likelihood of subsequent response to paclitaxel suggests an important role for this agent in the treatment of refractory metastatic breast cancer.

High-dose chemotherapy with peripheral blood progenitor autografting

Mobilized PBPs are an acceptable alternative to ABMT for hematopoietic rescue following high-dose therapy (table 10-3). Platelet recovery appears to be faster following PBPs than ABMT. In most series, leukocyte recovery is also accelerated, but this may be particularly due to the use of colony-stimulating factor. Morbidity and mortality also appear to be reduced. The optimal mobilization methodology is not defined, but larger numbers of PBPs are mobilized by chemotherapy plus colony-stimulating factors compared to CSFs alone, at the cost of enhanced toxicity. The use of PBPs has also facilitated the study of very-high-intensity regimens in which multiple courses of high-dose chemotherapy are given at very short intervals. Following completion of feasibility studies, prospective random assignment trials will be necessary to determine the benefit, if any, of this approach.

Factors affecting the mobilization of primitive and committed hematopoietic progenitors into the peripheral blood of cancer patients

Rapid hematopoietic reconstitution following peripheral blood progenitor cell (PBPC) autotransplantation is thought to result from reinfusion of committed progenitor cells. This has raised concern that PBPC autografts might be rich in committed hematopoietic progentors responsible for early engraftment, but deficient in more primitive progenitors required for long-term hematopoietic reconstitution. The granulomonocytic colony-forming unit (CFU-GM) assay measures committed progenitors responsive to a single species of colony-stimulating activity such as granulocyte-macrophage colony-stimulating factor (GM-CSF), whereas the pre-CFU assay identifies more primitive progenitors by measuring interleukin-3 (IL-3) and kit ligand (KL) induced generation of secondary CFU-GM from CD34+, 4-hydroperoxycyclophosphamide resistant progenitors that require multiple cytokine stimuli. Paired bone marrow (BM) and PBPC samples from 17 breast and ovarian cancer patients participating in four separate clinical trials were compared in these assay systems. In seven of nine patients, PBPC autografts mobilized with cyclophosphamide rebound and G-CSF compared favorably with paired BM autografts in both committed and primitive progenitor capacity. Failure to mobilize substantial primitive progenitor cell numbers occurred in two of nine patients undergoing this mobilization regimen and could not have been predicted by either circulating CFU-GM or CD34+ cell number. Prior myelosuppressive treatment experiences reduced peripheral progenitor yields somewhat, but still allowed for the collection of PBPC autografts which compared favorably with BM autografts in total CFU-GM and Pre-CFU. Mobilization of PBPC with G-CSF or GM-CSF alone in patients who had received prior myelosuppressive therapies produced autografts which were relatively deficient in committed progenitors, but absolutely deficient in primitive progenitors. We conclude that optimization of patient characteristics and mobilization parameters can achieve PBPC autografts rich in both the primitive and committed hematopoietic progenitor cells.

Taxol (paclitaxel) plus recombinant human granulocyte colony-stimulating factor in the treatment of metastatic breast cancer

We treated 28 patients who had no prior chemotherapy for stage IV breast cancer and 51 patients with extensive prior exposure to other chemotherapeutic agents with a 24-hour infusion of Taxol (paclitaxel) as a single agent. Prophylactic recombinant human granulocyte colony-stimulating factor was administered routinely to ameliorate the anticipated dose-limiting toxicity of neutropenia. Nonhematologic toxicity was mild to moderate in most cases. Taxol was more active in patients with chemotherapy-naive stage IV disease, but activity was also observed in extensively treated patients as well. There is a strong clinical suggestion of at least partial noncross-resistance with doxorubicin. Taxol is a very promising agent for the treatment of metastatic breast cancer; its optimal application in this disease will be the subject of future trials.

Excretion of Ascaris lumbricoides during total body irradiation

We describe the excretion of Ascaris lumbicoides, an intestinal roundworm, in the emesis of an asymptomatic patient undergoing total body irradiation. This suggests that Ascaris is sensitive to irradiation.