PSEUDOPROGRESSION AND MIXED RESPONSES IN METASTATIC RENAL CELL CARCINOMA PATIENTS TREATED WITH NIVOLUMAB: A RETROSPECTIVE ANALYSIS

INTRODUCTION

Immune checkpoint inhibitors (ICI) are part of the current standard of care for metastatic clear-cell renal cell carcinoma (m-ccRCC). ICI can elicit diverse tumor response, including atypical responses such as pseudoprogression (psPD), mixed responses (MR) and late responses. We aimed to analyze the occurrence and prognostic impact of atypical responses in m-ccRCC patients treated with nivolumab.

MATERIALS AND METHODS

A retrospective analysis of m-ccRCC patients treated with nivolumab in first or subsequent therapy line between November 2012 and July 2022 was performed. All radiographic evaluations of eligible patients were analyzed using the iRECIST consensus guideline.

RESULTS

We assessed 247 baseline target lesions in 94 eligible patients. MR occurred in 11 (11.7%) patients: in 7 at first CT (computed tomography) evaluation (CT1) and in 4 at second CT evaluation (CT2). In 8 patients (73%), MR evolved to confirmed PD. In 3 patients (27%), MR evolved towards a partial response (PR) and was thus a psPD. psPD occurred in 8 (8.5%) patients: with psPD features at CT1 in 3 patients, with psPD features at CT2 in 2 patients, and with MR features at CT1 in 3 patients. psPD patients had similar progression-free survival and overall survival compared to patients displaying PR as best response without a phase of psPD. 76 patients were treated beyond immune unconfirmed progressive disease (iUPD) at any moment: 12 (16%) of them evolved towards PR or stable disease (SD). Treatment beyond immune confirmed PD (iCPD) in 20 patients did not lead to PR or SD.

CONCLUSION

Atypical responses such as psPD and MR occurred in 8.5% and 11.7% of m-ccRCC patients treated with nivolumab at CT1 and CT2. Patients with psPD had favorable outcomes, while MR most often evolved to progression. Treatment with nivolumab beyond iCPD did not lead to tumor stabilization or regression.

Overall survival improvement in patients with metastatic clear-cell renal cell carcinoma between 2000 and 2020: a retrospective cohort study

BACKGROUND

Only a few recent phase III trials with targeted therapies or immune checkpoint inhibitors (ICIs) in metastatic clear-cell renal cell carcinoma (m-ccRCC) demonstrated an overall survival (OS) benefit compared to standard of care. We aimed to study the evolution of OS since the start of systemic therapy from 2000 to 2020.

PATIENTS AND METHODS

Retrospective study on all consecutively treated m-ccRCC patients in three Belgian hospitals starting with systemic therapy. The study outcome was OS since the start of systemic therapy. We used a univariable Cox model for OS with year of the start of therapy as a predictor, and a multivariable analysis including known prognostic factors. Linear and non-linear trends of time were tested.

RESULTS

Five hundred patients were included. In a linear model, the HR for OS depending on the year of the start of therapy was 0.95 (95%CI 0.93-0.97; p < 0.0001), estimated for an increase with 1 year in time. In a non-linear model, OS started to improve from 2006 on, when vascular endothelial growth factor receptor tyrosine kinase inhibitors (VEGFR-TKIs) replaced interferon alfa (IFNa) as a standard of care and continued to increase steadily during the following years. On multivariable analysis, the year of the start of therapy remained an independent prognostic factor for OS. Two-year OS after the start of systemic therapy was 23%, 34%, 50% and 59% for patients who started treatment in 2000-2005, 2006-2011, 2012-2017, and 2018-2020, respectively. The five-year OS of the first three groups was 7%, 14% and 24%. The mean number of administered lines of therapy increased over time, with an incidence rate ratio of 1.07 (95%CI 1.05-1.08; p < 0.0001) per year increase for the period 2000-2016.

CONCLUSION

OS of m-ccRCC patients has been improving significantly over the last 15 years since the introduction of VEGFR-TKIs and ICIs.

Treatment of patients with newly diagnosed metastatic hormone sensitive prostate cancer (mHSPC) in Belgium: a real world data analysis

INTRODUCTION

Abiraterone acetate + prednisone (AAP) and docetaxel have proven their efficacy in the treatment of patients with newly diagnosed metastatic hormone-sensitive prostate cancer (mHSPC) in clinical trials. However, real-world data are scarce. The goal of this study is to evaluate real-world data on the efficacy and safety of these therapies in mHSPC patients.

PATIENTS AND METHODS

Records of 93 patients from 21 different centres were retrospectively reviewed. Primary and secondary endpoints were radiographic and PSA progression-free survival (RPFS - PSA-PFS) and cancer specific and overall survival (CSS - OS), respectively. Adverse events (AEs) were evaluated according to the Common Terminology Criteria for Adverse Events version 5.0. Differences in oncological outcome and AEs were evaluated between three treatment groups: ADT only (N=26) - ADT + AAP (N=48) - ADT + docetaxel (N=19). Survival analysis was performed using Kaplan-Meier statistics.

RESULTS

Median RPFS was 13 months (95% confidence interval [CI]: 9-17) for ADT only, 21 months (95% CI: 19-23) for ADT + AAP and 12 months (95% CI: 11-14) for ADT + docetaxel (p = 0.004). The 1-year PSA-PFS, CSS and OS were 73.5%, 90.7% and 88.7%, respectively, with no significant differences between the three groups. Adverse events of grade 3 or higher were not observed more frequently.

CONCLUSION

Retrospective real-world data show a significantly longer RPFS for mHSPC patients treated with ADT + AAP compared to ADT only or ADT + docetaxel at short-term follow-up. This can aid in counselling of mHSPC patients in daily clinical practice.

Abstract PS9-06: Adherence to and patient satisfaction with the combination therapy of exemestane and everolimus in postmenopausal women with HR+ HER2- advanced breast cancer: Results from the IPSOC-mamma study

BackgroundEverolimus in combination with exemestane is indicated for the treatment of hormone receptor-positive, HER 2-neg endocrine resistant advanced breast cancer in postmenopausal women. This study investigated treatment adherence, tolerability, satisfaction and efficacy.

MethodsA prospective, non-interventional, non-controlled, multicentric observational study assessed adherence by means of a validated questionnaire (‘Morisky Medication Adherence Scale’) and ‘Medication Event Monitoring System’ (MEMS®) data. The level of adherence was calculated per patient as percentage of days on which the medicine was taken as prescribed during the total treatment period, referred to as ‘unadjusted adherence rate’ (UAR). Second, MEMS® data were adjusted for treatment interruptions according to the CRF and questionnaire data, approved by the treating physician (‘adjusted adherence rate’ (AAR)). Successful adherence was defined as ≥ 95% – ≤ 105%. Validated questionnaires (‘Patient Satisfaction with Cancer Treatment Education’, ‘Cancer Treatment Satisfaction Questionnaire’ (CTSQ) and ‘Functional Assessment of Cancer Therapy – General’ (FACT-G) were used to report patients experience and satisfaction with the treatment and perceived care, questioned at initial visit and after approximately 1, 3, 6 and 12 months. The efficacy was primary analyzed through progression free survival (PFS).

ResultsBetween Dec 2015 and Nov 2017, a total of 58 women (median age 65 yrs) from 7 oncology centers were included after a mean of 34m ± 36.9 (SD) of being diagnosed with stage IV disease; most (62.1%) had ≥3 organs involved and 84.5% had ≥2 prior metastatic treatment lines. The mean follow-up duration was 185.5 ± 100.0 days. The mean UAR for exemestane, everolimus and the combination were 92.9 %, 84.8 % and 81.7 % respectively. For everolimus and the combination therapy these rates differ significantly from the mean AAR, with p &lt; 0.05 (see table 1). For the AAR of the combination therapy, 13.8 % of the patients showed optimal adherence (100 %).

Six patients (10.3%) interrupted their treatment with exemestane with a mean time of treatment pause of 34.3 ± 19.1 days. The treatment with everolimus was interrupted by 36 (62.1%), with a mean interruption time of 24.3 ± 16.5 days, which corresponds with a mean of 19.6 % ± 17.6% of the total follow-up duration. Some patients interrupted their treatment multiple times. The most common side effect was mucositis (n=26 at 1 month, of whom 8 patients grade 3 and 15 patients grade 2)). Six (10.4 %) of the 58 patients stopped treatment with everolimus and exemestane due to side effects. The median PFS was 170 days. With regard to quality of life, patients scored lowest on emotional and functional well-being. However, there were no significant differences measured for the mean FACT-G score between Day0, M1 and M3 (P = 0.273). Also, patients scored overall low on the ‘CTSQ’.

Conclusion Despite close monitoring and preventive measures to overcome side effects, adherence to everolimus and exemestane was rather low. Many patients needed to interrupt the treatment due to side effects; treatment is perceived as intensive. Nevertheless, median PFS is 170 days, even when used late in the therapeutic journey of breast cancer patients.

Table 1. UAR and AAR for Exemestane, Everolimus and the combinationExemestaneEverolimusCombination therapyUAR (%)mean ± SD92.97 ± 13.1784.86 ± 19.4081.74 ± 20.98AAR (%)mean ± SD93.07 ± 13.1491.81 ± 15.0487.55 ± 18.17Significance differenceP-value0.277&lt; 0.001&lt; 0.001

Citation Format: Veerle Foulon, Carrie Visser, Sandra De Coster, Lise-Marie Kinnaer, Ellen Reynders, Anne Deblander, Patrick Berteloot, Kevin Punie, Hans Wildiers, Véronique Cocquyt, Hannelore Denys, Ahmad Awada, Eric Strobbe, Andrea Gombos, Isabelle Spoormans, Ximena Elzo-Kraemer, Christof Vulsteke, Marleen Borms, Philip Debruyne, Wim Wynendaele, Patrick Neven. Adherence to and patient satisfaction with the combination therapy of exemestane and everolimus in postmenopausal women with HR+ HER2- advanced breast cancer: Results from the IPSOC-mamma study [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS9-06.

Bone metastasis is associated with poor prognosis in metastatic papillary renal cell carcinoma patients treated with first agent angiogenesis inhibitors

OBJECTIVE

Papillary renal cell carcinoma (papRCC) is a rare (10%-15%) subtype of renal cancer. Few prognostic biomarkers have been described in metastatic papRCC (m-papRCC) patients treated with vascular endothelial growth factor receptor tyrosine kinase inhibitors (VEGFR-TKIs). We aimed to study the prognostic impact of bone metastases (BM) on response rate, progression-free and overall survival (PFS and OS) in patients with m-papRCC treated with first agent VEGFR-TKIs.

PATIENTS AND METHODS

A multicentric, retrospective analysis of patient records was conducted. BM were detected by computed tomography and/or bone scintigraphy. The International Metastatic RCC Database Consortium (IMDC) score was calculated at start of first agent VEGFR-TKI treatment.

RESULTS

Forty-nine patients were included. Best objective response was partial response in 20%, stable disease in 60% and early progressive disease in 20% of patients. Median PFS (mPFS) was 6.0 months and median OS (mOS) 14.0 months after start of first agent VEGFR-TKI. The IMDC score correlated with mOS: 77.5 months in good, 17.0 months in intermediate and 8.0 months in poor risk patients (P = 0.002). Patients with BM had a poorer outcome compared to patients without BM: mPFS was 4.0 vs. 7.0 months (P = 0.006) and mOS 7.5 vs. 19.0 months (P = 0.002). On bivariate analysis, the presence of BM was independently associated with PFS (P = 0.02) and OS (P = 0.049), independent of the IMDC risk groups.

CONCLUSION

In m-papRCC patients treated with first agent VEGFR-TKIs, the presence of BM is an unfavorable prognostic factor, associated with shorter PFS and OS.

Real-world use of granulocyte colony-stimulating factor in ambulatory breast cancer patients: a cross-sectional study

PURPOSE

To prevent febrile neutropenia (FN), European Organisation for Research and Treatment of Cancer (EORTC) guidelines recommend primary prophylaxis with granulocyte colony-stimulating factors (PPG) for patients at high risk (≥ 20%) of FN. In Belgium, the use of PPG is restricted by specific reimbursement criteria. The impact of these criteria on PPG use and adherence to guidelines is unknown.

METHODS

This multicentre, cross-sectional, observational study aimed to describe PPG use by FN risk category in breast cancer patients who were scheduled to receive myelosuppressive chemotherapy in outpatient clinics in Belgium during a 2-week period between 13 October and 12 December 2014.

RESULTS

In total, 490 patients were enrolled. Median age was 57.0 years. Based on their chemotherapy regimen, 53.9, 5.1 and 41.0% of patients were at a low, intermediate and high risk of FN, respectively. Overall, 39.8% of patients received PPG (17.0, 12.0 and 73.1% of those receiving low-, intermediate- and high-risk regimens, respectively). In the high-risk category, PPG was used in 89.9% of dose-dense and in 25.0% of classical chemotherapy regimens. PPG use was adherent to EORTC guidelines in 75.3% of patients (30.6% appropriate use, 44.7% appropriate non-use). EORTC guidelines would recommend PPG use in 46.1% of this study population (n = 226), and its use was reimbursable in Belgium in 76.1% of these patients (n = 172), but only 66.4% of them received PPG (n = 150).

CONCLUSIONS

Both Belgian reimbursement criteria and physician decision-making led to a proportion of patients for whom PPG treatment was recommended but finally not receiving it.

Tamoxifen Metabolism and Efficacy in Breast Cancer: A Prospective Multicenter Trial

Purpose: Levels of endoxifen, the most active metabolite of tamoxifen, vary by the highly polymorphic cytochrome P450 (CYP) 2D6 enzyme. We prospectively investigated tamoxifen efficacy by serum endoxifen levels and the tamoxifen activity score (TAS).Experimental Design: A prospective observational multicenter study included postmenopausal women with an estrogen receptor-positive breast cancer receiving first-line tamoxifen, 20 mg daily in the neoadjuvant or metastatic setting, recruited between February 2009 and May 2014. The primary endpoint was the objective response rate (ORR) using RECIST criteria 1.0. Secondary endpoints were clinical benefit (CB), progression-free survival (PFS), and tolerability of tamoxifen. The main analysis used logistic regression to relate ORR to serum endoxifen levels after 3 months. Endpoints were also related to other tamoxifen metabolites and to TAS.Results: Endoxifen levels were available for 247 of all 297 patients (83%), of which 209 with target lesions (85%). Median follow-up time for PFS was 32.5 months, and 62% progressed. ORR and CB were 45% and 84%, respectively. ORR was not related to endoxifen, and the OR of ORR was 1.008 per μg/L increase in endoxifen (95% confidence interval, 0.971-1.046; P = 0.56). In general, none of the endpoints was associated with endoxifen levels, tamoxifen metabolites, or TAS.Conclusions: Under the prespecified assumptions, the results from this prospective clinical trial do not suggest therapeutic drug monitoring of endoxifen to be of clinical value in postmenopausal women treated with tamoxifen for breast cancer in the neoadjuvant or metastatic setting. Clin Cancer Res; 24(10); 2312-8. ©2018 AACR.

Which Factors Predict Overall Survival in Patients With Metastatic Castration-Resistant Prostate Cancer Treated With Abiraterone Acetate Post-Docetaxel?

BACKGROUND

Abiraterone acetate (AA) increases overall survival (OS) in patients with metastatic castration-resistant prostate cancer (mCRPC) previously treated with docetaxel. However, survival time varies substantially between individuals. Our goal was to identify prognostic factors that better estimate OS.

MATERIALS AND METHODS

This is a retrospective multicentric analysis of 368 patients with mCRPC starting AA with prednisone after docetaxel. Cox proportional hazards statistics were applied. A multivariate model was constructed based on significant univariate predictors by using a manual stepwise forward and backward selection strategy. Model performance was determined by using receiver operating characteristic (ROC) curves.

RESULTS

Univariate analysis identified 20 significant OS predictors. A multivariate model was constructed, based on 220 patients, incorporating 5 independent risk factors for decreased OS at the time of AA initiation: hemoglobin < 12 g/dL (hazard ratio [HR] 2.02), > 10 metastases (HR 1.80), ECOG performance status ≥ 2 (HR 1.88), radiographic progression (HR 1.50), and time since diagnosis < 90 months (HR 1.66, all P < .05). Patients were stratified into 3 groups: good (0-2 risk factors, median OS 22.6 months), intermediate (3 risk factors, median OS 13.9 months), and poor prognosis (4-5 risk factors, median OS 6.2 months). The area under the ROC curve based on the event "death by the time of median OS (13.3 months)" was 0.736 (95% confidence interval 0.670-0.803).

CONCLUSION

We identified 5 readily available risk factors independently associated with decreased OS. The resulting model may be used for patient counseling in daily clinical practice, as well as patient stratification in clinical trials.

Adherence to oral anticancer drugs (OAD) in patients (pts) with metastatic renal cancer (mRCC): First results of the prospective observational multicenter IPSOC study (Investigating Patient Satisfaction with Oral Anti-cancer Treatment)

4622

Background: Patient adherence to oral therapy is a critical issue in cancer treatment. The aim of this study is to investigate the prevalence and severity of non-adherence to OAD in mRCC and to identify factors predictive of non-adherence. Methods: Prospective observational multicenter trial performed at 11 Belgian academic and non-academic centers. All pts with mRCC starting OADs (sunitinib, pazopanib, everolimus or sorafenib) are eligible for the study. Pts are contacted by phone at baseline and at 1, 3, 6 and 12 months. At each contact, pts are asked to complete questionnaires investigating 1) medication adherence (MMAS), 2) patient satisfaction with treatment (CTSQ) and with treatment education (PS-CaTE), 3) the extent of information desire (EID), 4) quality of life (FACT-G and FKSI) and 5) the role of the pharmacist (SWiP). Adherence is measured using an electronic medication event monitoring system (MEMS, Aardex). Results: Between 02/2011 and 11/2011, 49 pts (m: 33, f: 16) with a median age of 63 years (range 25 - 87) have participated in the IPSOC study. Twenty-nine pts (64%) were treated with an OAD in first-line, 15 pts (33%) in second-line. With a median follow-up of 131 days (range 2 - 313) 45 pts (92%) claimed to be fully adherent to their treatment (based on MMAS and CTSQ data). Four patients indicated to have missed at least one dose, of whom two indicated they occasionally forgot their medication and two others interrupted treatment because of side effects. Based on MEMS data, mean adherence, defined as the percentage of days with at least the prescribed number of dosage taken, was 98.91%. Conclusions: The IPSOC study, the first to examine adherence to OAD among mRCC pts, shows that mRCC pts are almost fully adherent to treatment recommendations. This seems to be in contrast to adherence data for other, long-lasting, anti-cancer treatments. Further investigations will focus on the question whether extensive counseling and participation in side-effect programs contribute to the high percentage of adherence in this study.

P5-14-24: The Long Term Prognostic Impact of Real-Time Quantitative RT-PCR Detection of Cytokeratin 19 mRNA in Preoperative Bone Marrow Aspirates of Early Breast Cancer Patients

Purpose: Several studies have evaluated the prognostic effect of bone marrow micrometastases at the time of surgery in early breast cancer, but few studies have long term outcome data. We report here a cohort with more than ten years follow-up.

Materials and methods: 131 patients with primary operable invasive breast cancer were enrolled in the protocol from February 1998 to September 1999. Bone marrow aspirates, obtained from the iliac crest or the sternum, were analyzed with real-time quantitative reverse-transcription polymerase chain reaction (RT-PCR) for the presence of cytokeratin 19 (CK19) mRNA. All patients received standard therapy and follow-up. After a median follow-up of 133 months, data about disease recurrence (invasive disease free survival, IDFS) and survival (breast cancer specific survival (BCSS) and overall survival (OS)) were collected. A control group consisted of archived cDNA samples from 38 patients with hematological malignant antecedents in complete remission and without known gene arrangements. The upper limit of the 95% confidence interval of the level of CK19 positive cells is this group was used as cut-off (260 cytokeratin 19+ cells / 5 × 106 leucocytes) to determine bone marrow status in breast cancer patients.

Results: 69 bone marrow samples from breast cancer patients (52,7 %) were considered CK19 positive. IDFS was 60.9 % and 79 % for CK19+ and CK19- patients, respectively (log-rank p-value = 0,036). When CK19 was evaluated as a continuous variable, IDFS also correlated significantly with the level of CK19 mRNA in bone marrow aspirates (p-value = 0,019). Except for lymph node status (ANOVA linear regression p-value = 0.022), there was no significant correlation between the level of CK19+ cells in the bone marrow and classical prognostic factors (pathological tumor stage, tumor size, differentiation grade, hormonal receptor status).

In multivariate Cox-regression analysis correcting for tumor size, differentiation grade, lymph node status, hormone receptor status, tumor stage and treatment modalities (surgical procedure, chemotherapy, radiotherapy and antihormonal therapy), the CK19 bone marrow status still was a significant predictor of IDFS. (p-value = 0.042)

Differences in BCSS (78 % of CK19 + patients and 84 % of CK19 — patients) and OS (75 % in CK 19 + patients and 74 % in CK 19 — patients) were not statistically significant. (log rank p-values 0.087 and 0.883, respectively).

Conclusion: This study demonstrates the long term (&gt;ten years) prognostic effect of CK19 mRNA detection with RT-PCR in the bone marrow of operable breast cancer patients.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-14-24.

Cancer and renal insufficiency results of the BIRMA study

Background:

Half of anticancer drugs are predominantly excreted in urine. Dosage adjustment in renal insufficiency (RI) is, therefore, a crucial issue. Moreover, patients with abnormal renal function are at high risk for drug-induced nephrotoxicity. The Belgian Renal Insufficiency and Anticancer Medications (BIRMA) study investigated the prevalence of RI in cancer patients, and the profile/dosing of anticancer drugs prescribed.

Methods:

Primary end point: to estimate the prevalence of abnormal glomerular filtration rate (GFR; estimated with the abbreviated Modification of Diet in Renal Disease formula) and RI in cancer patient. Secondary end point: to describe the profile of anticancer drugs prescribed (dose reduction/nephrotoxicity). Data were collected for patients presenting at one of the seven Belgian BIRMA centres in March 2006.

Results:

A total of 1218 patients were included. The prevalence of elevated SCR (⩾1.2 mg per 100 ml) was 14.9%, but 64.0% had a GFR<90 ml min⁻¹ per 1.73 m². In all, 78.6% of treated patients (n=1087) were receiving at least one drug needing dosage adjustment and 78.1% received at least one nephrotoxic drug. In all, 56.5% of RI patients receiving chemotherapy requiring dose reduction in case of RI did not receive dose adjustment.

Conclusions:

The RI is highly frequent in cancer patients. In all, 80% of the patients receive potentially nephrotoxic drugs and/or for which dosage must be adjusted in RI. Oncologists should check the appropriate dose of chemotherapeutic drugs in relation to renal function before prescribing.

Neoadjuvant capecitabine and docetaxel (plus trastuzumab): an effective non-anthracycline-based chemotherapy regimen for patients with locally advanced breast cancer

BACKGROUND

To evaluate capecitabine-docetaxel (XT), with trastuzumab (H) in human epidermal growth factor receptor 2 (HER2)-positive disease, in inoperable locally advanced breast cancer (LABC).

PATIENTS AND METHODS

Patients received up to six neoadjuvant 21-day cycles of capecitabine 900 mg/m(2) twice daily, days 1-14, plus docetaxel 36 mg/m(2), days 1 and 8. Patients with HER2-positive disease also received trastuzumab 6 mg/kg every 3 weeks. The primary end point was pathologic complete response (pCR) rate, evaluated separately in HER2-negative and HER2-positive cohorts. Secondary end points included clinical response rates and tolerability.

RESULTS

The pCR rate was 15% [95% confidence interval (CI) 7-28] in 53 patients receiving XT and 40% (95% CI 26-55) in 50 patients receiving HXT. After neoadjuvant therapy, 50 patients receiving XT and 45 receiving HXT underwent surgery. No unexpected toxicity was observed: the most common grade ≥3 adverse events were diarrhea/mucositis (30% and 20%, respectively) and grade 3 hand-foot syndrome (11% and 6%, respectively). Disease-free survival and overall survival were similar with XT and HXT after median follow-up of 22 months in the XT cohort and 21 months in the HXT cohort.

CONCLUSION

Neoadjuvant XT (HXT in HER2-positive disease) is highly effective in inoperable LABC, demonstrating pCR rates of 15% and 40%, respectively. This non-anthracycline-containing regimen offers obvious benefits in early disease, where avoidance of long-term cardiotoxicity is particularly important.

SUCON Trial (SUnitinib CONsolidation Therapy in Metastatic Breast Cancer): A Belgian Multicenter Phase II Randomized Trial in Her2 Negative Metastatic Breast Cancer Evaluating Consolidation Antiangiogenic Therapy with Sunitinib after Objective Response to Taxane Chemotherapy

Under the auspices of the Belgian Society of Medical Oncology (BSMO).Background: New drugs are generally tested in patients with metastatic disease where bulky tumor mass is present. However, antiangiogenic compounds are probably more beneficial in the prevention of regrowth from tumors with small tumor load than in bulky tumors. This study wants to test the hypothesis that antiangiogenic compounds such as sunitinib are able to delay tumor progression after tumor mass reduction by taxanes, i.e. an objective response (PR or CR).Materials and methods: This is a dual-arm open-label randomized multicenter phase II clinical trial with 2:1 randomization evaluating the efficacy of sunitinib (study arm) versus no therapy (control arm, only for descriptive purposes) in patients with metastatic breast cancer after objective response to taxane chemotherapy. Eligible patients had metastatic HER2 negative breast cancer, had received 10 to 20 weeks of first- or second line taxane containing chemotherapy resulting in an objective response (RECIST). Patients received sunitinib (arm A) 50 mg/d po 4w/6 (amended to 37.5 mg continuously in 1-2008) or no therapy (arm B). Patients were stratified for disease free interval and dominant site of disease. Patients randomized to arm B were offered the opportunity to receive open-label sunitinib treatment upon development of disease progression. Treatment was pursued until disease progression or major intolerance or patients refusal. All patients who received at least day 1 of study treatment were evaluated for efficacy, toxicity and safety. The duration of response after taxane treatment in previous studies with metastatic breast cancer is around 7 months. Based on this, the median time interval between the end of chemotherapy and tumor progression was expected to be about 5 months in our study population. The primary endpoint was to determine the proportion of patients alive and without disease progression (PFS) at 5 months after study entry in arm A. If ≤ 18/36 patients are progression-free and alive at 5 months, sunitinib will be declared insufficiently active (beta 0.05); if ≥ 22 patients are progression-free and alive at 5 months, sunitinib will be declared active (alpha 0.05) and it will be recommended to continue the trial as a phase III design.Results: 10/36 patients (28%) reached 5 months PFS in arm A and 4/19 in arm B (21%). Median PFS was 3.4 months in Arm A and 3.1 months in Arm B. Toxicity and overall survival data will be reported at the meeting.Discussion: This study does not confirm the hypothesis that sunitinib can lead to a significant proportion of patients with PFS of ≥ 5 months after objective response to taxanes. This proof-of-principle study suggests that also the role of consolidation therapy with other (already approved) antiangiogenic treatments should be evaluated carefully in prospective clinical trials (high economic cost).

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 203.

Weekly paclitaxel versus weekly docetaxel in elderly and frail patients with metastatic breast carcinoma having failed previous anthracyclines: a randomised phase II study of the Belgian Society of Medical Oncology

Abstract #6115

Rationale: Taxanes are considered as standard 2nd-line chemotherapy after anthracyclines in metastatic breast carcinoma (MBC). In one large randomized trial, Jones et al. (JCO 2005;23:5542) reported a mean objective remission rate (RR) of 32% with a median time to progression (TTP) of 24.6 weeks (wks) for 3-weekly docetaxel 100mg/m², while the corresponding figures for paclitaxel 175mg/m² were 25% and 15.6wks respectively. Nevertheless, excessive toxicity, especially myelosuppression, precludes their use in frail and/or elderly patients (pts). For the latter, weekly schemes were developed, which proved tolerable without losing efficacy. This randomized phase II trial investigated the efficacy and the tolerability of weekly docetaxel or paclitaxel in MBC pts considered unfit for a 3-weekly therapy. Eligibility criteria were age &gt;70 years, particular risk for myelosuppression (febrile neutropenia during previous chemotherapy, extensive radiation therapy, proven bone marrow invasion) or impaired hepatic function.&#x2028; Study design: 70pts accrued from Jan. 2002 to Aug. 2005 were randomized between arm A (33pts) receiving paclitaxel 80mg/m² weekly x8, and arm B (37pts), receiving docetaxel 36mg/m² weekly x8 after which a clinical response evaluation including CT-scan was performed. Pts with objective remission or stable disease (SD) pursued treatment 3/4 or 2/3 wks untill progression or unacceptable toxicity. For all pts, this was the first exposure to taxanes, unless they had received it in an adjuvant scheme, or in a palliative scheme with at least a 4 months lasting response. Study-endpoints were RR, TTP, overall survival (OS) and tolerability.&#x2028; Results: With paclitaxel, we obtained a RR of 55.2%, SD in 27.6% and progressive disease (PD) in 17.2% of the pts; median TTP was 21.1wks (95% CI:14.9-29.0) and median survival 55.7wks (95% CI:28.6-79.0). Corresponding results for docetaxel were: a RR of 45.2%, SD in 19.4% and PD in 35.4%; median TTP was 12.7wks (95% CI:8.4-29.3) and median survival 32wks (95% CI:19.4-50.9). Docetaxel and paclitaxel are known to have a different toxicity profile in 3-weekly regimens, with more hematotoxicity for docetaxel. In our study, boths products had a similar toxicity profile with more anemia, neutropenia and febrile neutropenia in the paclitaxel arm.&#x2028; Conclusions: Our study demonstrates that in pts with MBC unfit for 3-weekly docetaxel or paclitaxel, weekly administration of either compound may certainly be considered after anthracycline failure. They display different, but acceptable toxicity profiles, with levels of antitumoral efficacy comparable to those previously reported for 3-weekly regimens. A true valid comparison would require extension into a phase III trial.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6115.

Breast cancer and renal insufficiency

Abstract #6086

Background:&#x2028; The Belgian IRMA study (Renal Insufficiency and Anticancer Medications) reported the high prevalence of renal insufficiency (RI) in 1208 cancer patients, with a glomerular filtration rate (GFR) &lt;90 ml/min for 64%. Furthermore, 78.1% were receiving potentially nephrotoxic drugs and 78.8% drugs necessitating dosage adjustment in case of renal dysfunction. We present here the results for the 510 BIRMA patients with breast cancer.&#x2028; Methods:&#x2028; Data were collected for patients presenting at one of the 7 BIRMA centers in March 2006: tumor, sex, age, weight, height, serum creatinine (SCR), bone metastasis (BM) and anticancer drugs (including dose modification). Glomerular Filtration Rate (GFR) was estimated by the aMDRD formula.&#x2028; Results:&#x2028; 510 breast cancer patients were included: mean age 58.7 years, weight 68.1 kg, height 161.6 cm, 4 men, 46.9% of patients had BM. The prevalence of elevated SCR (&gt;=1.2 mg/dL) was 7.3%, of GFR&lt;90 ml/min/1.73m² 67.8%, and of GFR&lt;60 (threshold for many anticancer drugs to consider dose modification) 15.9% (Table). 86.6% of treated patients (n=486) were receiving at least one drug needing dosage adjustment in case of renal dysfunction and 73.4% received at least one potentially nephrotoxic drug. Furthermore, the prevalence of GFR&lt;90/60 was 74.9/24.3% for breast cancer patients with BM (Table). When comparing the prevalence of GFR&lt;90 between patients with or without BM (for patients with available GFR), the frequency of RI was significantly higher for BM patients (78.9 vs 69.9%, p=0.03).&#x2028; Conclusions:&#x2028; The results of the BIRMA study showed that RI is highly frequent in breast cancer patients in Belgium and that nearly 94% of the patients receive potentially nephrotoxic drugs and/or drugs for which dosage must be adjusted in RI. Furthermore, patients with BM had a higher rate of RI than patients without. These frequencies are higher compared to data from the NHANES study in the US general population, especially for breast cancer patients with a stage 3 RI for whom SCR was normal in 55.7% of the cases. This underlines that estimating renal function with formulae such as aMDRD is mandatory in every breast cancer patient, even when SCR is within the normal range.&#x2028; &#x2028;

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6086.

Coexistence of light chain disease and chronic lymphocytic leukaemia, a complex karyotype with a rapid fatal outcome

We report on a 48-year-old man with concomitantly diagnosed kappa expressing chronic lymphocytic leukaemia (CLL) and lambda light chain disease with highly complex chromosomal aberrations. The clinical course of the disease was very aggressive with survival of only 1 month. We demonstrate the distinct clonal origin by cytogenetic data and immunoglobulin rearrangement studies. To our knowledge this is the first report of a light chain disease associated with CLL.

Detection of micrometastatic disease and monitoring of perioperative tumor cell dissemination in primary operable breast cancer patients using real-time quantitative reverse transcription-PCR

PURPOSE

We previously found a statistically significant number of cytokeratin 19 (CK19)+ cells in peripheral blood (PB) of stage IV breast cancer (BC) patients compared with those of healthy volunteers, using a quantitative real-time reverse transcription-PCR. We aimed to apply the technique on bone marrow (BM) of primary operable BC patients. Pre- and postoperative PB samples of these patients were further analyzed to investigate possible shedding of CK19+ cells during the operation.

EXPERIMENTAL DESIGN

In 54 primary operable BC patients, we analyzed 50 BM samples taken preoperatively and 297 PB samples. PB samples were collected before surgery; immediately after surgery; on the first, second, and fifth day postoperatively; and one month postoperatively.

RESULTS

In BM of controls and BC patients, we detected a median of 28 and 568 CK19+ cells/5 x 10(6) leukocytes, respectively (P < 0.001). In preoperative blood (B-1) samples, we measured a median of 109 CK19+ cells. Using the upper limit of 95% confidence interval of controls as cutoff, 74% and 52% of BM and (B-1), respectively were considered CK19+. There was no significant correlation between CK19+ cells in BM and (B-1) and classical prognostic factors. We found no significant difference between blood samples at different time points with respect to the average CK19+ cells.

CONCLUSIONS

In primary BC patients, we detected high numbers of CK19+ cells in BM and PB (B-1) samples compared with controls. However, no significant correlation between the presence of CK19+ cells in BM and PB and classical prognostic factors was found. We detected no statistically significant influence of surgical manipulation on CK19+ cells.

Real-time quantitative RT-PCR and detection of tumour cell dissemination in breast cancer patients: plasmid versus cell line dilutions

BACKGROUND

We previously developed a real-time quantitative RT-PCR technique to detect breast carcinoma cells in peripheral blood (PB). The aim of the current study was to improve cytokeratin 19 (CK19) quantification using plasmid dilutions of cloned PCR fragments to obtain a more reliable and reproducible quantification of CK19 transcripts.

MATERIALS AND METHODS

PB samples of 14 stage IV breast cancer patients and 23 healthy controls were examined with RT-PCR using plasmid quantification.

RESULTS

Median CK19+ copy numbers of one and 11 were detected in the control group and stage IV breast cancer patients, respectively (Mann-Whitney, P </=0.0001). When comparing the results obtained using cell line dilutions with those obtained using plasmid dilutions, a good correlation was observed (r(2) = 0.98).

CONCLUSIONS

Plasmid dilutions are more reliable than cell line dilutions for quantification of gene expression, and more objective criteria for positivity could be defined based on the characteristics of the standard curve (slope and intercept). A more universally accepted agreement on the definition of the cut-off value for positivity is needed.

Phase I and pharmacokinetic study of continuous twice weekly intravenous administration of Cilengitide (EMD 121974), a novel inhibitor of the integrins alphavbeta3 and alphavbeta5 in patients with advanced solid tumours

A single-agent dose escalating phase I and pharmacokinetic study with Cilengitide, an inhibitor of the integrins alphavbeta3 and alphavbeta5, was performed to determine its safety and toxicity. Cilengitide was administered as a one-hour infusion twice weekly without interruption to patients with histologically- or cytologically-confirmed metastatic solid tumours. Plasma pharmacokinetics were determined at days 1 and 15. 37 patients were enrolled into the study. Dose levels studied were 30, 60, 120, 180, 240, 400, 600, 850, 1200, and 1600 mg/m(2)/infusion. There was no dose-limiting toxicity (DLT). Pharmacokinetics were dose-independent and time-invariant. Apparent terminal half-life ranged from 3 to 5 h. At 120 mg/m(2)/infusion, peak plasma concentrations were attained that optimally inhibited tumour growth in preclinical models. Cilengitide can be safely administered using a continuous twice-weekly infusion regimen. As DLT was not reached, future trials should explore Cilengitide at different doses.

PNU-145156E, a novel angiogenesis inhibitor, in patients with solid tumors: a phase I and pharmacokinetic study

Our aim was to establish, in patients with solid tumors, the dose-limiting toxicity, maximum tolerated dose (MTD), and pharmacology of PNU-145156E, a new sulfonated distamycin A derivative that blocked circulating angiogenesis-promoting growth factors in animal studies and exhibited an antitumor effect in murine solid tumors. In a Phase I study, PNU-145156E was administered i.v. every 6 weeks. Included were patients with solid tumors; an Eastern Cooperative Oncology Group performance score </=1; and normal bone marrow, renal, and liver functions and blood clotting tests. Excluded were patients with brain metastases or on steroid medication. Toxicity was scored with the National Cancer Institute Common Toxicity Criteria. Plasma and urine PNU-145156E was measured for pharmacokinetic analysis. The effect of PNU-145156E on serum basic fibroblast growth factor (bFGF) was measured by sandwich ELISA. Twenty-nine patients (median age, 54 years; range, 33-71 years; 19 males and 10 females; median performance score = 1) were treated at dose levels of 100-1050 mg/m(2). We observed, during 47 treatment cycles, erratic but short-lasting decreases of antithrombin III levels (<75%) at all dose levels. Other clotting tests remained normal except during thromboembolic events. Dose-limiting toxicity was thrombophlebitis, pulmonary embolism, and grade 3 dyspnea. PNU-145156E disappeared from the circulation, decreasing triexponentially with a long terminal half-life of 1 month. No significant change in bFGF and no objective tumor responses were observed. Disease stabilization was achieved in four patients. In conclusion, the MTD of PNU-145156E was 1050 mg/m(2). Serum bFGF level was not affected by PNU-145156E up to the MTD.

A real-time quantitative reverse transcriptase polymerase chain reaction (RT-PCR) to detect breast carcinoma cells in peripheral blood

BACKGROUND

The detection of occult carcinoma cells in patients with breast cancer has been shown to predict disease recurrence and metastasis.

MATERIALS AND METHODS

To improve on molecular detection of breast carcinoma cells in blood, we have developed a sensitive and quantitative assay using real-time quantitative RT-PCR identifying transcripts of the cytokeratin-19 (CK19) gene.

RESULTS

This real-time quantitative RT-PCR is sensitive, accurate and has a high reproducibility within a wide dynamic range, which permits simultaneous quantitative analysis of samples with varying input concentrations. Furthermore, the procedure offers several technical advantages over classic quantitative PCR methods (competitive RT-PCR, Northern blotting) such as decreased likelihood of contamination due to absence of post-PCR manipulations, high sample throughput because of absence of post-PCR processing time (no agarose gel electrophoresis). In this pilot study, we detected significantly elevated CK19 transcript levels in < 10% of the volunteers, in +/- 30% of stage I-IIIa patients preoperatively and in > 70% of the and stage IV breast cancer patients.

CONCLUSIONS

Analyses using this real time quantitative RT-PCR for CK19 mRNA may prove to have clinical implications in the assessment of circulating tumour cells in peripheral blood, micrometastases in bone marrow or lymph nodes in breast cancer patients. Application of this technique in a clinical population may improve diagnosis and monitoring of metastatic breast cancer and its validation is currently ongoing.

Vascular targeting of solid tumours: a major 'inverse' volume-response relationship following combretastatin A-4 phosphate treatment of rat rhabdomyosarcomas

Tumour-specific vascularisation may be therapeutically approached in two different ways: by antiangiogenic treatments specifically directed to dividing and migrating endothelial cells, or by agents that target principally the inadequate and ill-structured tumour vasculature. Combretastatin A-4 phosphate (combreAp), a recently synthesised prodrug (OXiGENE, Lund, Sweden), is a vascular targeting agent of the latter kind. We evaluated the effect of a single intraperitoneal (i.p.) combreAp injection on the growth of rhabdomyosarcomas syngeneic in WAG/Rij rats. Different tumour volume groups, ranging between 0.1 and 27 cm(3), were selected to assess the relationship between the size at treatment time and the response to combreAp. A double combreAp treatment (2x25 mg/kg) was investigated within the same overall aim: the relationship between growth delay and tumour size. Our results show that the systemic administration of combreAp induces a clear-cut differential growth delay in the solid rat rhabdomyosarcomas: with very large tumours (>/= 14 cm(3)), a 17.6-fold stronger effect was measured than with very small tumours (<1 cm(3)). This is the 'inverse' of the volume-response seen with the conventional therapeutic approaches (radiotherapy, chemotherapy or surgery). These combreAp antitumour responses were observed without treatment limiting systemic toxicity in the rats. With clinical digital subtraction angiography, using microsurgical cannulation of a major tumour draining vessel, and with histopathology, we demonstrate that growth delay is related to an early (within 3-6 h) and extensive breakdown of tumour blood vessels. The experiments involving a second injection also indicate a volume-dependent effect of combreAp in reducing the regrowth rate of small or large rhabdomyosarcomas. This significant differential volume-response obtained with 'selective' vascular targeting, stronger in larger tumours than smaller ones, suggests the potential of broadening the therapeutic window.

Vascular endothelial growth factor measured in platelet poor plasma allows optimal separation between cancer patients and volunteers: a key to study an angiogenic marker in vivo?

BACKGROUND

Serum VEGF levels are elevated in cancer patients and are used as a tumor marker in different malignancies. We have measured VEGF levels in different blood compartments in cancer patients and healthy volunteers in order to assess the most suitable way of processing blood for measuring VEGF as a marker of tumor-angiogenesis.

PATIENTS AND METHODS

VEGF concentrations were analyzed by an enzyme-linked immunosorbent assay in serum (VEGFS), EDTA plasma (VEGFEDTA), citrated plasma (VEGFC), CTAD-plasma (VEGFCTAD), platelet poor plasma (VEGFPPP), platelet rich plasma after induction of platelet activation (VEGFPRP). Platelet activation was assessed by measuring PF4 concentrations in different plasma samples.

RESULTS

We observed higher VEGFS (P = 0.0027), VEGFEDTA (P = 0.003) and VEGFPPP (P = 0.0007) levels in cancer patients than in volunteers; VEGFPRP concentrations showed no significant difference (P = 0.208). Analysis of the correlation between VEGFplt and VEGFS in cancer patients showed a similar correlation in a comparable VEGFS concentration range as in the volunteers. When comparing VEGFC to VEGFCTAD, we find significantly higher VEGF and PF4 levels in citrated plasma (VEGF: P = 0.00019; PF4: P = 0.00023).

CONCLUSIONS

It is likely that VEGFS in cancer patients encompass platelet-delivered VEGF and VEGF from other sources, notably from (neo)-angiogenesis in tumoral tissue. The best discrimination between volunteers and cancer patients was observed in PPP. As generating plasma can induce platelet activation, with consequent VEGF release from platelets, we suggest that to assess free circulating VEGF, CTAD plasma should be used.

Neoadjuvant/primary chemotherapy in cancer treatment: what advantage?

Neoadjuvant chemotherapy refers to the initial systemic treatment for patients who present with localised cancer for whom there is an alternative but less than completely effective local treatment. There are a multiple reasons for the use of neoadjuvant chemotherapy, but, there may be potential disadvantages. Several neoplasms in which neoadjuvant chemotherapy, if effective, can allow less mutilating surgery and neoplasms in which clinical trials indicate an expanding role for neo-adjuvant therapy are discussed.

Angiogenesis: possibilities for therapeutic interventions

Vascular proliferation normally occurs only during embryonic development, the female reproductive cycle and wound healing. Various pathological conditions such as diabetic retinopathy are characterized by persistent, uncontrolled angiogenesis. At the other hand, impaired development of new blood vessels has been found to be related with myocardial infarction. A series of anti-angiogenic drugs are currently included in experimental cancer treatment, whereas the failure of ulcers to heal may be limited by increased angiogenesis upon administration of growth factors. In the present review control mechanisms of the vasculature are summarized and therapeutic approaches discussed.