A personalized sunitinib (S) first-line approach in elderly patients with metastatic renal cell carcinoma (mRCC)

602

Background: About 24% of mRCC are older than 74 yo. S is a well-established first-line therapy for mRCC with a specific toxicity profile requiring a dose reduction in 30% of pts. Actually few data are available in the Literature about its use in patients > 75 yo especially as regards efficacy and cost effectiveness of tailored approaches. Methods: The primary end-point of this prospective single arm study, is to assess if a personalized approach is able to decrease the rate of dose reduction to 8% after the first cycle of S.. 19 pts have been estimated to be necessary to explore this hypothesis. Secondary objectives were the safety, treatment duration (TD) and overall survival (OS). Personalized approach was defined as the starting dose of S choose by the medical oncologist based on performance status (PS ECOG) and number of comorbidities. Results: From 2007 to 201421 pts were enrolled. The median age was 77.9 yrs (IQR 74.1-82.1). Seventy-five % had a clear cell carcinoma, 20% had a metastatic disease at diagnosis and 60% had > 2 sites of metastasis. All pts had PS ECOG ≥ 1 and 50% suffered from > 2 comorbidities. 43% were good, 52% intermediate and 5% poor prognosis by IMDC criteria. 3 pts (14%) started S at 50 mg/d, 9 pts (42%) at 37.5 mg/d and 9 pts (42%) started with 25 mg/d. All pts received S with the 4/2 schedule. The dose reduction after the first cycle was 28%. The reason was always toxicity, but no treatment interruption occurred. No pts starting at 25 mg had dose modification. The main toxicity requiring dose reduction was G3 anemia in 1pt, G3-4 thrombocytopenia in 3 pts and G3 leuconeutropenia in 3 pts . The median TD was 11.9 mos (95%CI, 6.5-17.3). The median OS was 33.3 mos (95%CI, 26.1-40.6). Conclusions: This study shows that a personalized starting dose is not able to decrease the rate of dose reduction at first cycle. Nonetheless a personalized strategy does not affect negatively the OS of elderly pts. Actually in elderly pts a disease stabilization without acute adverse events, could be considered an adequate goal. A well tolerated therapy could also be cost effective because part of health cost, especially for elderly pts, derives from their hospitalization for adverse events. Further data are required.

Impact of dose reduction on survival in patients starting sunitinib (SU) or pazopanib (PA) as first-line for metastatic renal cell carcinoma (mRCC)

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Background: SU and PA are both VEGFR TKI approved for treatment of mRCC. Previous studies reported that the reduced dose (RD) is not recommended for the beginning of therapy (Motzer et al. 2012) and suggested a direct correlation between dose and effectiveness of therapy (Houk et al. 2010). We aim to investigate if patients (pts) that decreased the dose during treatment have different outcomes compared to those who continue a standard dose (SD). Methods: All pts affected by mRCC who started SU or PA at SD have been included. Pts were divided into two groups: RD and SD, based on whether they reduced the therapy or not. The main reasons for dose change have been collected and the RD group was defined into 2 levels (1st level: SU37.5mg/d, 4/2 or PA 600mg/d; 2nd level: SU25mg/d, 4/2 or PA 400mg/d). Pts were stratified by IMDC prognostic criteria and differences in pts’ characteristics between RD and SD groups were evaluated as well as median PFS and OS. Results: A total of 280 pts have been included. Median age was 62y and 68% was male; 54% had good prognosis, 40% intermediate and 6% poor. First-line was SU in 84% and PA in 16% of cases. A total of 123 (44%) pts decreased the dose to first- (89%) or second-level (11%). The main reasons were hand-foot syndrome (17.9%), diarrhea (15.4%) asthenia (14.6%), mucositis (13.0%) and thrombocytopenia (11.4%). Significant differences between RD and SD groups were the female sex (40% vs. 25%; p = 0.01) and the rate of primary refractory disease (11% vs. 31%: p < 0.001). Median PFS and OS were 12.4 and 34.9 mos, respectively. In RD group, the median time before dose reduction was 3.5 mos. Excluding the primary refractory pts, median PFS was 18.6 and 15.0 mos (p = 0.06) and median OS was 68.0 and 40.7 mos (p = 0.14) in RD and SD group, respectively. In RD group, no differences between 1st- and 2nd-level of dose were observed both in PFS (11.0 vs. 13.1 mos; p = 0.82) and OS (42.8 vs. 36.0 mos; p = 0.78) after reduction. Conclusions: Dose reduction is a frequent event in pts who started a first-line therapy with SU or PA. This study reports that DR does not affect the survival of pts who initially started SU and PA at standard dose.

Abstract PD6-5: Pooled analysis of circulating tumor cells in metastatic breast cancer: Findings from 1944 individual patients data

Background: Clinical validity of CTCs (CellSearch®) in metastatic breast cancer (MBC) patients has previously been assessed in studies with limited statistical power. We aimed to pool all European studies to obtain high-level evidence on the prognostic value of CTCs, to investigate their effects across different clinico-pathological characteristics and therapies and to further validate the MD Anderson/Institut Curie/Fox Chase CTC-based prognostic nomogram established in first-line treated MBC patients (Giordano et al, Clin Cancer Res 2013).

Material and methods: Methods were predefined in a written protocol. In December 2012, we searched for eligible studies that accrued patients in 2003-2012. We contacted all European laboratories using CellSearch®. We used likelihood ratio tests (LR) in Cox regression models stratified by study to assess the independent prognostic value of CTC when added to a clinicopathological (CP) model for progression-free (PFS) and overall survival (OS). Landmark analyses were used to assess the prognostic effect of early changes in CTC. The CTC-based nomogram (http://cancernomograms.com/CTCOnline.html) score was retrieved for every patient; we calculated C-indices, drew calibration plots and Kaplan-Meier curves according to quintiles of the nomogram score.

Results: We collected individual data of 1944 MBC patients, from 20 different studies (some unpublished), from 17 centers in 7 European countries. We observed 1507 PFS events and 929 deaths. Baseline CTC count was significantly associated with several patient characteristics, such as performance status (PS, p&lt;10-4), synchronous metastasis (p&lt;10- 2) tumor subtype (p&lt;10-4), liver & bone metastases (p&lt;10-4), CEA & CA15-3 levels (p&lt;10-4). The CP model for OS included PS, MBC subtypes, number of previous lines of treatment, patient's age, metastasis-free interval, metastatic sites (p&lt;0.01 for all). In a multivariate analysis containing the CP model parameters and CTC count at baseline, elevated CTC count (≥5) was a significant independent predictor of OS (n = 1444, HR = 2.7, 95%CI [2.2-3.2], LR p&lt;10-4). Baseline serum markers added either no or marginal effect to the CP plus baseline CTC model for OS. In contrast, early changes in CTC status at week 3-5 significantly added prognostic information for OS to the model with CP factors and baseline CTC+ (n = 569, HR = 1.8 [2.2-3.2], LR p&lt;0.001). In the population of interest (MBC treated by first line chemotherapy, n = 402 patients, 176 deaths), the CTC-based nomogram exhibited a good C-index for OS (0.69), was well calibrated and showed clear separation of the survival curves. Additional results, including subgroup analyses by tumor subtype and treatments will be presented at the meeting.

Conclusions: This pooled analysis is the largest study ever reported on CTC in MBC, with a previously unreached statistical power. It provides a clear level-of-evidence 1 on the independent prognostic value of CTCs before and during treatment in MBC. Also, the CTC-based prognostic nomogram is independently validated.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr PD6-5.

Detection of circulating tumor cells (CTCs) in stage T3-4 and/or N positive rectal cancer (RC) patients undergoing neoadjuvant therapy followed by curative surgery

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Background: CTCs count at baseline and during treatment is an independent prognostic factor in metastatic colorectal cancer, while its role in early stages is still an open issue. No data are available in RC patients suitable for neoadjuvant chemoradiotherapy (CT-RT). Aim of the study: To investigate the role of CTCs in patients with locally advancedRC undergoing neo-adjuvant CT-RT. Methods: In a prospective single Institution study, cT3-4 and/or N+RC staged by rectal EUS and/or pelvic MRI and chest-abdomen CT scan, received capecitabine (825 mg/mq, orally, tid) with concurrent pelvic radiotherapy (50.4 Gy/28 fractions), followed by two cycles of intermittent capecitabine (1250 mg/mq, tid 14/21 days) and by low anterior resection or abdominopelvic resection with TME. Primary endpoints are evaluation of CTCs at baseline (t0), after CT-RT (t1), within 7 days after surgery (t2), and at 6-month from surgery (t3) and its correlation with main patient/tumor characteristics, CEA and response to neoadjuvant therapy. CTCs are enumerated with CellSearch System in 22.5 ml peripheral blood at over-mentioned time-points. A repeated measure analysis for binary outcome was used to evaluate changes in time of the percentage of patients with CTCs>0. Results: 85/90 patients are evaluable: 52M/33F, median age 63 yrs (range 37-82); median follow up 25 months (range 6-52). At baseline (t0) 13 pts had 1 CTC (15.3%), two had 2 CTCs (2.4%) and one had 27 CTCs(1.2%) while in 69 cases (81.2%) no CTCs were detected. Information on CTCs was available for 67 patients at t1, 68 patients at t2 and 62 at t3. CTCs>0 was reported on 16 (18.8%) at t0, 5 (7.5%) at t1, 6 (8.8%) at t2 and 3 (4.8% ) at t3 (P-value for trend: 0.039). CTCs at t0 was not statistically associated with any patient/tumor characteristics except for ultrasound T-stage that showed a trend CTCs (0% in uT2, 18.9% in uT3 and 40% in uT4, p-value 0.093), while no correlation with pCR was reported. Conclusions: CTCs count ≥ 1 was observed in 18.8% of patients with trend reduction over time probably due to therapy. Statistical correlation will be planned between CTCs and outcome.

A meta-analysis of receptor status discordance between primary breast cancer and metastases

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Background: There is an increasing awareness that biology of breast cancer may evolve over time. The discordance in estrogen (ER), progesterone (PgR) and HER2 receptor status between primary breast cancer and metastases is being intensively investigated and a large amount of data has been produced. However, results from different studies seem to be conflicting and heterogeneous. To highlight this issue, a meta-analysis of published data was performed. Methods: A literature search was performed with Medline. All studies published from 1983 to 2011 comparing changes inER, PgR and/or HER2 status in patients with matched breast primary and recurrent tumors were included. We used random-effects models to estimate pooled discordance proportions. Results: We selected 42 articles, mostly reporting retrospective studies. Twenty-eight, 20 and 27 articles were focused on ER, PgR and HER2 changes, respectively. A total of 2806 tumors were evaluated for ER discordance, 1809 for PgR discordance and 2801 for HER2 discordance. The heterogeneity between study-specific discordance proportions was high (I2 >75%, p<0.0001) for ER, PgR and HER2. Pooled discordance proportions were 20% (95% CI: 16-25%) for ER, 33% (95% CI: 28-38%) for PgR and 9% (95% CI: 6-12%) for HER2. Pooled proportions of tumors shifting from positive to negative and from negative to positive were 24% and 12% for ER (p=0.0115), respectively. The same figures were 44% and 15% for PgR (p<0.0001), and 14% and 6% for HER2 (p=0.04). Conclusions: To our knowledge, this is the first meta-analysis addressing this topic. The findings strengthen the concept that changes in receptor expression may occur during the natural history of breast cancer and therefore clinical implications with possible impact on treatment choice cannot be excluded. However, the high heterogeneity observed in our analysis may explain the disagreement among oncologists on performing a reassessment of the biological features. In our opinion, only high-powered prospective and randomized trials could clarify the controversies in this field.

A prognostic model for predicting breast cancer (BC)-related survival in operable triple-negative (TN) patients (pts)

1049

Background: TNBC represent a heterogeneous disease in terms of biology, prognosis, and treatment response. We propose a prognostic model to identify homogeneous subgroups of patients and tailor risk-adapted adjuvant therapies indications. Methods: We analyzed 1,049 pts operated in our institute from 1997 to 2007 for early TNBC. Pts who received neoadjuvant chemotherapy (CT), with T4 tumors or previous history of cancer were excluded. Death from BC was the primary endpoint of the study. We calculated an individual predicted risk using a multivariable Cox regression model, with age, tumor size, number of positive lymph nodes and Ki-67 analyzed as continuous covariates, and tumor grade and perivascular invasion as categorical covariates. Results: Median age was 52 years, 562 (53.4%) and 670 (65.1%) pts had a pT1 and pN0 TNBC, respectively. Median Ki-67 was 48%. Adjuvant CT regimens were distributed as follows: classical CMF 388 (37.0%), anthracycline containing regimens 455 (43.4%), taxanes 12 (1.1%), other regimens 66 (6.3%) and no CT 128 (12.2%). After a median follow-up of 6 years, 131 deaths from BC were observed (5-year cumulative incidence 11.9%). At multivariable analysis, age, tumor size, number of positive lymph nodes, Ki-67, tumor grade and perivascular invasion were associated with the risk of death and were included in the prognostic model. Its predictive accuracy was good (C-index 0.73). We subsequently identified three homogeneous prognostic subgroups - low, medium and high-risk - according to the tertiles values of the predicted risk. The outcomes are shown in the table. Conclusions: We could identify homogeneous prognostic subgroups of TNBC pts according to clinical-pathological features. This prognostic model suggests that the use of CT in TN low-risk pts might be questionable. We are currently externally validating this model on a different series of pts. [Table: see text]

Role of breast surgery in T1-T3 breast cancer patients with synchronous bone metastases

1115

Background: The role of breast surgery in advanced breast cancer (ABC) is controversial. The main potential advantage of removing the primary tumor is to eliminate the source of further metastatic spread. While previous studies addressed the question in very heterogeneous populations (e.g. patients with any local and distant extension), we have focused on a homogeneous series of ABC patients. Methods: From our institutional Tumor Registry we selected 191 consecutive women diagnosed between 2000 and 2008 with locally operable (T1-T3) ABC, synchronous bone metastases and no other distant sites involved. The progression free survival (PFS) was calculated from diagnosis to the date of progression, defined as either a new site of metastatic disease or clinical/radiographic evidence of increasing tumor burden at a previously known bone metastatic site. Results: Median age was 51 years and 92% of the women had an endocrine-responsive tumor. One-hundred and thirty patients out of 191 (68%) underwent surgery at the time of diagnosis, while 61 (32%) did not. Twenty-six of the operated patients (20%) had previously undergone neoadjuvant chemotherapy; 15 (12%) had positive or undetermined surgical margins. Operated and non-operated patients were similar with respect to age, tumor size, nodal involvement, estrogen and progesterone receptor status, HER2 overexpression and Ki-67, but differed in terms of number of bone metastatic sites: a single metastasis was detected in 34 (26%) operated and 7 (11%) non-operated cases (P=0.02). First-line treatment strategies with endocrine therapy, chemotherapy and Trastuzumab were similarly distributed between the two groups. The 5-year PFS was 22.0% and 10.4% in operated and non-operated patients, respectively. The multi-adjusted hazard ratio was 0.62 (95% confidence interval 0.39-0.98) in favor of surgery. The exclusion of the patients who had received neoadjuvant chemotherapy and patients with positive or undetermined surgical margins did not alter the results. Conclusions: In this large and homogeneous series of ABC patients with synchronous bone metastases, the role of breast surgery had a favorable impact on the progression of the disease, indicating a potential survival benefit.

Cetuximab/radiotherapy (CET+RT) versus concomitant chemoradiotherapy (cCHT+RT) with or without induction docetaxel/cisplatin/5-fluorouracil (TPF) in locally advanced head and neck squamous cell carcinoma (LASCCHN): Preliminary results on toxicity of a randomized, 2x2 factorial, phase II-III study (NCT01086826)

5513

Background: The standard treatment options for LASCCHN are cCHT+RT or CET+RT. Strategies to improve the efficacy with the integration of induction chemotherapy are being investigated. Primary endpoints of this study were to compare: 1) the overall survival (OS) of induction vs. no induction arms; 2) the Grade(G)3-4 in-field toxicity of cCHT+RT vs. CET+RT. Methods: Patients (pts) with unresectable LASCCHN, stage III-IV, ECOG PS 0–1 were randomized to a 2x2 factorial design: Arm A1: cCHT+RT (2 cycles of ciplatin/5fluorouracil); Arm A2: CET+RTX; Arm B1: 3 cycles of TPF followed by the same cCHT+RT; Arm B2: 3 cycles of TPF followed by CET+RT. A total of 204 deaths over 420 pts ( including the 101 randomized in the phase II part of the study comparing cCHT+RT with or w/o induction TPF) were required to detect a HR of death of 0.675 (A1+A2 vs. B1+B2; 2-sided a=0.05; b=0.20) and a 10% difference in G3-4 in-field mucosal toxicity (A1+B1 vs. A2+B2). Results: By February 2012, 387 pts over 413 pts were evaluable for toxicity. 82% of pts were male; median age was 60y; PS: 0=77.8% and 1=22.2%. Disease stage was III (31%) or IV (69%). Sites of disease were oral cavity (21.7%), oropharynx (54.8%), hypopharynx (23.5%). At a median follow-up of 21 months, 126 deaths occurred. Data on G3-4 in-field toxicity (primary endpoint) and compliance to cCHT+RT vs CET+RT are shown in the table. Conclusions: No advantage for CET+RT over cCHT+RT was observed regarding G3-4 in-field toxicities and feasibility. Pts are still being followed-up to assess OS. [Table: see text]

Metastatic renal cell carcinoma (mRCC) in elderly patients: Can a personalized approach be an effective therapeutic option?

468

Background: Renal cell carcinoma (RCC) is the third most common genitourinary cancer. Up to 30% of patients (pts) with RCC presents with advanced disease. Sunitinib(S), an orally available tyrosine kinase inhibitor, is the well established first-line therapy for these population. Actually few data are available in the literature about its use in patients > 75 yrs investigating the feasibility, the efficacy and the toxicity in this population.

Methods: From 2007 to 2011, 16 pts >75 yrs with mRCC received S. 75% of pts had a clear cell carcinoma, 87.5% had a surgery on primary tumor, 18.7% had a metastic disease at diagnosis and the median time to metastatic progression was 13.5 months. Median age was 78 years (range 71-88y).All patients had 0-1 performance status and 69% of them received S as first-line treatment. Four pts started S on the approved 50 mg /d 4-week-on-2-off schedule, but three of them reduced to 37.5 mg continuous once daily dosing(ODD)starting from the third cycle. Five out of 8 pts receiving 37.5 mg continuous ODD reduced the dose at 25 mg continuous ODD or modified the schedule. Four pts started with 25 mg continuous ODD and 2 of them continued the treatment at modified schedule. Median number of cycles administered was 7 (range 2-16).

Results: Response rate was 87% (13pts) in 15 evaluable pts. Overall response included 40% (6 pts) of PR, 20% (3pts) of CR, 33% (5pts) of SD > 6 mos. Progressive disease was observed only in 1patient. TTP was 12.4 months (95% CI, 4.8-32.6). Overall survival was 34.2 months (95% CI, 27.3- ). The main toxicity requiring dose reduction or schedule modification was haematological (46%), G3Anemia in 1 pt G3-4 thrombocytopenia in 3pts and G3 leukoneutrophenia in 3pts. No any toxicity required treatment interruption.

Conclusions: In summary these results show the feasibility and the efficacy of S in elderly population with high response rate regardless the doses and schedule used.

Circulating endothelial cells (CECs), progenitors (CEPs), and circulating tumor cells (CTCs) for prediction of response in patients with advanced breast cancer (ABC) receiving metronomic oral vinorelbine (oV): Preliminary results

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Background: Metronomic administration of chemotherapy given once or more per week with no extended gaps was shown to be effectively anti-angiogenic, causing growth arrest or apoptosis of endothelial cells in tumor neo-vessels. Preclinical and clinical studies indicate that ultra-low concentrations of various microtubule inhibitors inhibit proliferation or migration of endothelial cells. We investigated in a phase II study the activity of metronomic administration of oV in ABC, kinetics and response prediction of CECs, CEPs, CTCs and of other biomarkers of angiogenesis (soluble VEGF, VEGFr2, TSP1, bFGF). CT perfusion scans were also performed. Methods: From February 2008, 47 pts with ABC received oV (50 mg/die TTW). Currently 20 pts are evaluable for both activity and biomarker assessment. Baseline levels of biomarkers of angiogenesis were correlated with clinical response. Results: Shown in Table . Conclusions: We found that the baseline value of apoptotic cells (expressed as % of total cells) was significantly correlated with outcome. The baseline total, viable, and apoptotic CEC count and CTCs might provide an indirect measure for angiogenic turnover and an indicator of better response to anti-angiogenic therapy, supporting the use of metronomic treatments in patients expressing high levels of baseline CECs. Updated results will be presented together with correlation with perfusion CT scan and levels of CTCs.

[Table: see text]

No significant financial relationships to disclose.

Adjuvant therapy for very young women with breast cancer: response according to biologic and endocrine features

Incidence of breast cancer in patients aged < 20 years has been estimated to be 0.1 per 100,000 women. Reported incidences are 1.4 for women aged 20-24 years, 8.1 for women aged 25-29 years, and 24.8 for women aged 30-34 years. Younger patients have been found to have a more aggressive presentation of disease at diagnosis, which is associated with dire prognoses compared with those in premenopausal older patients. Several biologic features might explain the more aggressive behavior of breast cancer in younger patients: higher grade and higher expression of Ki67, higher occurrence of vessel invasion, and less expression of estrogen and progesterone receptors. Choice of adjuvant therapies for women aged <35 years with breast cancer is based on data derived from trials on cohorts of older patients. On average, the effect of chemotherapy for premenopausal patients is substantial: recent evidence suggested that very young women with endocrine-responsive tumors had a higher risk of relapse than older premenopausal patients with similar tumors. This was not the case for patients with endocrine-nonresponsive tumors, for which effects of chemotherapy were similar across ages. Very young women with this disease are faced with personal, family, professional, and quality-of-life issues that further complicate the phase of treatment decision-making. The development of more effective therapies for very young women with breast cancer requires tailored treatment investigations and research focused on issues specific to these patients.

Intrathecal chemotherapy in carcinomatous meningitis from breast cancer

Meningeal metastases occur in 2-3% of patients with breast cancer, leading to neurological morbidity and increased mortality. The criteria for treatment choice are controversial and intrathecal chemotherapy (ITC) has no documented role in the management of this disorder. We therefore evaluated the efficacy of an ITC regimen for patients presenting with carcinomatous meningitis from breast cancer.

PATIENTS AND METHODS

Patients with meningeal carcinomatosis with or without concomitant parenchymal brain metastasis, were treated with repeated courses of intrathecal chemotherapy according to the following alternated weekly schedule: Day 1: Thiotepa 10 mg, methotrexate 15 mg, hydrocortisone 30 mg; Day 5: cytarabine (Ara-C) 70 mg, methotrexate 15 mg, hydrocortisone 30 mg. Folinic acid 15 mg was given orally, every six hours after methotrexate on days 2-3 and 6-7.

RESULTS

Thirteen consecutive patients were treated. The median age was 45 (range 30-67) years. Eleven patients had performance status (PS) 2-3. Nine patients had other metastatic sites; synchronous parenchymal brain metastasis were present in 5 patients. Concomitant systemic chemotherapy was administered in 5 patients and external whole brain radiotherapy in 7 patients. With 12 evaluable patients we observed no responses or improvement in symptoms. Side-effects were minimal.

CONCLUSION

In our series of patients, ITC failed to provide objective response or relief in clinical symptoms. Despite evidence reported in the literature indicating symptomatic improvement after ITC in a number of patients with leptomeningeal metastasis, the results of our study confirm the controversial role of ITC. New drugs and new modalities of treatment should be studied in order to efficiently control meningeal involvement of breast cancer.