Randomized trial of preoperative docetaxel with or without capecitabine after 4 cycles of 5-fluorouracil– epirubicin–cyclophosphamide (FEC) in early-stage breast cancer: exploratory analyses identify Ki67 as a predictive biomarker for response to neoadjuvant chemotherapy

This randomized, multicenter study compared the efficacy of docetaxel with or without capecitabine following fluorouracil/epirubicin/cyclophosphamide (FEC) therapy in operable breast cancer and investigated the role of Ki67 as a predictive biomarker. Patients were randomized to 4 cycles of docetaxel/capecitabine (docetaxel: 75 mg/m² on day 1; capecitabine: 1,650 mg/m² on days 1–14 every 3 weeks) or docetaxel alone (75 mg/m² on day 1 every 3 weeks) after completion of 4 cycles of FEC (5-fluorouracil 500 mg/m², epirubicin 100 mg/m² and cyclophosphamide 500 mg/m² on day 1 every 3 weeks). The primary endpoint was the pathological complete response (pCR) rate. Predictive factor analysis was conducted using clinicopathological markers, including hormone receptors and Ki67 labeling index (Ki67LI). A total of 477 patients were randomized; the overall response in the docetaxel/capecitabine and docetaxel groups was 88.3 and 87.4 %, respectively. There were no significant differences in the pCR rate (docetaxel/capecitabine: 23 %; docetaxel: 24 %; p = 0.748), disease-free survival, or overall survival. However, patients with mid-range Ki67LI (10–20 %) showed a trend towards improved pCR rate with docetaxel/capecitabine compared to docetaxel alone. Furthermore, multivariate logistic regression analysis showed pre-treatment Ki67LI (odds ratio 1.031; 95 % CI 1.014–1.048; p = 0.0004) to be a significant predictor of pCR in this neoadjuvant treatment setting. Docetaxel/capecitabine (after 4 cycles of FEC) did not generate significant improvement in pCR compared to docetaxel alone. However, exploratory analyses suggested that assessment of pre-treatment Ki67LI may be a useful tool in the identification of responders to preoperative docetaxel/capecitabine in early-stage breast cancer.

A phase II study of metronomic paclitaxel/cyclophosphamide/capecitabine followed by 5-fluorouracil/epirubicin/cyclophosphamide as preoperative chemotherapy for triple-negative or low hormone receptor expressing/HER2-negative primary breast cancer

PURPOSE

Better treatments for triple-negative breast cancer (TNBC) are needed. To address this need, we studied the effects of preoperative metronomic paclitaxel/cyclophosphamide/capecitabine (mPCX) followed by 5-fluorouracil (FU)/epirubicin/cyclophosphamide (FEC) as preoperative chemotherapy in TNBC patients.

METHODS

Forty primary TNBC patients received four cycles of metronomic paclitaxel (80 mg/m(2) on Days 1, 8, and 15), cyclophosphamide (50 mg/body daily), and capecitabine (1,200 mg/m(2) daily), followed by four cycles of 5-FU (500 mg/m(2)), epirubicin (100 mg/m(2)), and cyclophosphamide (500 mg/m(2)) every 3 weeks. The primary end point was the pathological complete response (pCR) rate.

RESULTS

Forty patients formed the intent-to-treat population. The median dose intensities of paclitaxel, cyclophosphamide, and capecitabine were 89.7, 92.1, and 89.8%, respectively. Five patients discontinued mPCX and two discontinued FEC, primarily because of adverse events, resulting in a per-protocol population (PPS) of 33 patients. The pCR (ypT0/Tis ypN0) rate was 47.5% (19/40) in the intent-to-treat population and 54.5% (18/33) in the PPS. The clinical response rates were 36/40 (90.0%) and 31/33 (93.9%) in the intent-to-treat and PPS, respectively. The breast conservation rate was 72.7% (24/33), and 5/13 patients underwent partial resection instead of pre-planned total mastectomy. Grade 3-4 adverse events included neutropenia (35%), leukopenia (25%), and hand-foot syndrome (8%).

CONCLUSIONS

Metronomic PCX followed by FEC chemotherapy was associated with a high pCR rate and low toxicity in TNBC patients. Further studies of this regimen in larger numbers of patients are warranted.

On the zero-bias anomaly and Kondo physics in quantum point contacts near pinch-off

We investigate the linear and non-linear conductance of quantum point contacts (QPCs), in the region near pinch-off where Kondo physics has previously been connected to the appearance of the 0.7 feature. In studies of seven different QPCs, fabricated in the same high-mobility GaAs/AlGaAs heterojunction, the linear conductance is widely found to show the presence of the 0.7 feature. The differential conductance, on the other hand, does not generally exhibit the zero-bias anomaly (ZBA) that has been proposed to indicate the Kondo effect. Indeed, even in the small subset of QPCs found to exhibit such an anomaly, the linear conductance does not always follow the universal temperature-dependent scaling behavior expected for the Kondo effect. Taken collectively, our observations demonstrate that, unlike the 0.7 feature, the ZBA is not a generic feature of low-temperature QPC conduction. We furthermore conclude that the mere observation of the ZBA alone is insufficient evidence for concluding that Kondo physics is active. While we do not rule out the possibility that the Kondo effect may occur in QPCs, our results appear to indicate that its observation requires a very strict set of conditions to be satisfied. This should be contrasted with the case of the 0.7 feature, which has been apparent since the earliest experimental investigations of QPC transport.

Abstract P3-14-05: Randomized phase II study of preoperative docetaxel and cyclophosphamide-containing chemotherapy for luminal-type breast cancer

Background: We compared and evaluated three 6-cycle, docetaxel and cyclophosphamide (TC)-containing chemotherapy regimens in a multicenter randomized phase II study. The main aim was to investigate whether anthracyclines are needed or can be omitted, and whether the order of chemotherapy is important, for treating luminal-type breast cancer.

Methods: We recruited patients (pts) with ER-positive, HER2-negative breast cancer aged 20–70 years, and histo-pathologically invasive breast cancer (T1c-3, N0-1, M0), T≤7cm. Pts were randomized to 3 groups for the following treatments: 6 cycles of TC; 3 cycles of 5-FU/epirubicin/cyclophosphamide (FEC) followed by 3 cycles of TC (FEC-TC); and 3 cycles of TC followed by 3 cycles of FEC (TC-FEC). TC treatment consisted of administration of docetaxel at 75 mg/m2 and cyclophosphamide at 600 mg/m2 once every 3 weeks. FEC treatment consisted of administration of 5-FU at 500 mg/m2, epirubicin at 100 mg/m2, and cyclophosphamide at 500 mg/m2 once every 3 weeks. We aimed to enroll 65 pts per group based on an expected pCR rate among regimens of adding 10% at a threshold of 9%. The primary endpoint was pathological complete response (pCR) rate. Secondary endpoints were overall response rate (ORR), breast conservation rate and safety.

Results: A total of 195 pts (median age, 49.5 years (range, 26–69); median tumor size, 32.8 mm (range, 9–82); 91 pts with N(+) (51%)) were enrolled and randomized as follows: FEC-TC (n = 65), TC-FEC (n = 63), and TC group (n = 67). There were no differences in backgrounds among groups. Both the intention-to-treat population and the safety analysis set included 65, 63 and 65 pts in these groups, respectively. The 6-cycle treatment completion rates were 96.9%, 96.8% and 84.6%, respectively. pCR, defined as yT0/isyN0, was achieved by 9.2% of pts in the FEC-TC group, 8.1% in the TC-FEC group, and 15.9% in the TC group (p = 0.321). A quasi pCR in breast (yT0/is and near pCR) was achieved by 13.9%, 14.5%, and 17.5%, respectively. These responses did not differ among the 3 groups. ORRs, assessed by MRI or CT, were 75.8% (CR: 12.9%), 75% (CR: 5%), and 82.2% (CR: 17.9%) in the FEC-TC, TC-FEC and TC groups, respectively. Breast conservation rates were 50.8%, 45.2%, and 73.0%, respectively.Adverse events of Grade≥3 were observed in 20.0%, 27.0%, and 20.3% of pts in the FEC-TC, TC-FEC, and TC groups, respectively, with no significant differences. Febrile neutropenia was observed in 17.2%, 21.0%, and 11.3%, respectively, but in most cases it was managed sufficiently on an outpatient basis. Of 28, 27 and 23 pts in these groups in whom mastectomy was planned, 9 (32%), 5 (19%), and 10 (44%) were successfully converted to undergo breast-conserving surgery. Of 37, 35 and 40 pts in the FEC-TC, TC-FEC and TC groups in whom breast-conserving surgery was planned, 13 (35%), 12 (34%), and 4 (10%) underwent mastectomy.

Conclusion: Six cycles of TC had therapeutic effects and safety equivalent to FEC-TC and TC-FEC. The 3 treatment groups showed similar pCR rates, although the breast conservation rate was significantly higher in the TC group than in the other 2 groups. It may be possible to conduct preoperative chemotherapy for pts with ER-positive breast cancer without using an anthracycline.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-14-05.

Optical imaging of retina in response to grating stimuli in cats

We examined the intrinsic signals in response to grating stimuli in order to determine whether the light-evoked intrinsic signals of the retina are due to changes in the photoreceptor activities induced by the image projected on to the retina or are due to neural activities of the inner retina. The retinas of the left eye of 12 cats under general anesthesia were examined by a functional imaging fundus camera. Near infrared light was used to monitor the reflectance changes (RCs) of the retina. Vertical grating were used to stimulate the retina at 4 Hz. The spatial frequencies of the gratings were 0.05, 0.11, 0.22, 0.43, 0.86, 1.73, and 3.46 cycles/degree (cpd). Ten images were averaged and used to analyze the RCs to obtain the peak value (PV) of a two dimensional fast Fourier transfer of the RCs. The wavefront aberrations (WA) were measured with a compact wavefront aberrometer and the spatial modulation transfer function (MTF) of the eye was calculated. The retinal reflectance image had a grating pattern. The PV of the spatial sensitivity curve was highest at low spatial frequencies (0.05 and 0.11 cpd), and the sensitivity decreased steeply with an increase in the spatial frequency. RCs were not detectable at 3.46 cpd. The MTF decreased gradually with increases in the spatial frequencies and was 0.68 at 3.46 cpd. The reflectance pattern of the retinal intrinsic signal elicited by grating stimuli of different spatial frequencies was different from that of the MTF. This suggests that the intrinsic signal represents not only the response of the photoreceptors but also other neuronal or vascular changes in the retina.

Feasibility of 2nd generation STS retinal prosthesis in dogs

We developed a 2(nd) generation suprachoroidal transretinal stimulation (STS) system with a 49 channel electrode array and implanted in 2 dogs. One month after surgery, all electrodes were functioning and the ocular fundus was normal in both dogs. The results indicate the 2(nd) generation STS retinal prosthesis is feasible and can be considered for clinical use.

Abstract P1-14-02: Preoperative docetaxel (T) with or without capecitabine (X) following epirubicin, 5-fluorouracil and cyclophosphamide (FEC) in patients with operable breast cancer (OOTR N003): Results of comparative study and predictive marker analysis

Objective: This preoperative study aimed to evaluate the efficacy of 4 cycles of TX compared with 4 cycles of T, following 4 cycles of FEC in operable breast cancer patients.

Methods: Women with operable breast cancer (T1C-3N0M0/T1-3N1M0) were randomly assigned to receive either T (75 mg/m2, q3) plus X (825 mg/m2 bid, days 1 to 14) or T alone (75 mg/m2, q3) after completion of FEC (5-fluorouracil 500 mg/m2, epirubicin 100 mg/m2, cyclophosphamide 500 mg/m2, q3). Patients who had disease progression on FEC were excluded from randomization. The primary endpoint was pathological complete response (pCR). Predictive factor analysis was conducted using clinicopathological markers such as hormone receptors, Ki67 labeling index (Ki67LI) and thymidine phosphorylase (TP).

Results: From November 2005 to October 2009, 504 patients were enrolled and 239 and 238 patients were assigned to TX and T group, respectively (median age 49 years, median tumor size 3.5 cm and node positive rate 56%). Treatment discontinuation was observed in 22% of TX group and 5% in T group (p < 0.0001). The major reasons for discontinuation were toxicity, refusal/ consent withdrawal and several others. No significant difference in pCR rate was shown between the two groups (TX 23% and T 24%, p = 0.748). Neither clinical response nor surgical outcome differed between TX and T. The pCR rate in patients who had therapy discontinuation or dose-reduction on TX was 23%, whereas pCR rate in those on T was 11%. A subpopulation treatment effect pattern plots method indicated a trend that TX may improve the pCR rate in patients having a middle range of pretreatment Ki67LI, such as 10%–20%. In the median follow-up time of 3.7 years, disease-free survival (DFS) was not different between TX and T (3-year DFS: 92% in TX and 91% in T; hazard ratio 0.907, 95%CI 0.528–1.557, p = 0.723). The frequency of major grade 3 or greater adverse events of TX and T were leukopenia, 36% and 34%, febrile neutropenia 8% and 5%, and hand-foot syndrome 15% and 2%, respectively.

According to the analysis for evaluating predictive values of biomarkers, a multivariate logistic regression analysis showed that HER2 (+/−: odds ratio 4.107, p < 0.0001), Ki67LI (continuous variables: 1.029, p = 0.003), hormone receptor status (+/−: 0.457, p = 0.009), stroma TP status (0.523, p = 0.02) and grade (1/3: 0.387, 2/3: 0.532, p = 0.047) had statistical significant values for predicting pCR. A multiple Cox model in landmark analysis showed that tumor size (p < 0.0001), cancer cell TP status (p = 0.005), pCR and posttreatment Ki67LI (p = 0.016), and age (p = 0.049) were associated with DFS significantly.

Conclusions: Addition of X to T showed no superiority to T alone following FEC in neoadjuvant treatment of these patients with operable breast cancer. Treatment discontinuation rate was significantly higher in TX than T group, however the pCR rate in patients in TX group who required treatment discontinuation or dose-reduction was similar to that in patients who completed as scheduled, which was different from T group. Determination of pre-/ post-treatment Ki67LI looks useful for predicting pCR and DFS.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P1-14-02.

Phasic bursts of the antagonistic jaw muscles during REM sleep mimic a coordinated motor pattern during mastication

Sleep-related movement disorders are characterized by the specific phenotypes of muscle activities and movements during sleep. However, the state-specific characteristics of muscle bursts and movement during sleep are poorly understood. In this study, jaw-closing and -opening muscle electromyographic (EMG) activities and jaw movements were quantified to characterize phenotypes of motor patterns during sleep in freely moving and head-restrained guinea pigs. During non-rapid eye movement (NREM) sleep, both muscles were irregularly activated in terms of duration, activity, and intervals. During rapid eye movement (REM) sleep, clusters of phasic bursts occurred in the two muscles. Compared with NREM sleep, burst duration, activity, and intervals were less variable during REM sleep for both muscles. Although burst activity was lower during the two sleep states than during chewing, burst duration and intervals during REM sleep were distributed within a similar range to those during chewing. A trigger-averaged analysis of muscle bursts revealed that the temporal association between the bursts of the jaw-closing and -opening muscles during REM sleep was analogous to the temporal association during natural chewing. The burst characteristics of the two muscles reflected irregular patterns of jaw movements during NREM sleep and repetitive alternating bilateral movements during REM sleep. The distinct patterns of jaw muscle bursts and movements reflect state-specific regulations of the jaw motor system during sleep states. Phasic activations in the antagonistic jaw muscles during REM sleep are regulated, at least in part, by the neural networks involving masticatory pattern generation, demonstrating that waking jaw motor patterns are replayed during sleep periods.