Abiraterone acetate in patients with metastatic castration-resistant prostate cancer: Long term outcome of the Temporary Authorization for Use program in France

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Background: COU-AA-301 trial has proved that abiraterone acetate (AA), a selective inhibitor of androgen biosynthesis, improved overall survival (OS) of patients with metastatic castration resistant prostate cancer (mCRPC) after a first line of docetaxel. Based on this result, a temporary use authorisation (TUA) was performed between December 2010 and July 2011 to provide patients with mCRPC the opportunity to receive AA before its commercialization. The aim of this study was to evaluate safety and efficacy of AA treatment in this TUA. Methods: Between December 2010 and July 2011, we conducted an ambispective, multicentric cohort study and investigated data from 20 centres participating to the AA TUA for patients presenting mCRPC and already treated by a first line of chemotherapy (CT). Statistical analyses of the data were performed using the Stata software v13 to identify predictive and prognostic factors. Results: Among the 408 patients, 306 were eligible with a follow-up at 3 years. Median OS was 37.1 months from beginning of CT and 14.6 months from AA introduction. 211 patients (69%) received ≥ 3 months of AA and 95 patients (31%) were treated less than 3 months. In the multivariate analyses, duration of AA was significantly correlated with PSA decrease at 3 months. Additionally, shorter time under AA treatment, presence of multiple sites of metastasis and previous hormonal treatment duration were three independent factors associated with poorer OS. At the time of analysis ten patients were still under treatment for more than 3 years. Conclusions: Biochemical response monitored by PSA changes at 3 months is a strong predictive factor for AA treatment duration. Some high responders’ patients could beneficiate from AA for more than 3 years.

Androgen deprivation therapy (ADT) plus docetaxel (D) versus ADT alone for hormone-naïve metastatic prostate cancer (PCa): Long-term analysis of the GETUG-AFU 15 phase III trial

140

Background: ADT is standard treatment for metastatic PCa. Recently, the E3805 trial reported a survival benefit for (ADT+D) in high volume disease (HVD) patients, whereas the GETUG-15 trial did not demonstrate a survival improvement among a less selected group of patients (pts) with hormone-naïve metastatic PCa. We report an updated analysis of overall survival (OS) of the GETUG 15 trial and aligned the definition of HVD and low volume disease (LVD) subgroups. Methods: Long-termOS was analyzed in the intention-to-treat population (n=385 pts). Additionally, we retrospectively assessed the tumor volume as defined per E3805criteria in all patients enrolled in GETUG 15. Results: See Table. With a median follow-up of 82.9 months (95%CI [80.5-84.3]) (vs 50 months (95%CI [80.5-84.3] in the original analysis), 212 patients (55%) have died. The median OS is 46.5 [39.1-60.6] and 60.9 months [46.1-71.4] in the ADT and in the ADT + D arms, respectively (HR: 0.9 [95%CI: 0.7-1.2]). In HVD patients (n=183, 47.5%), median OS rates were 35.1 months [29.9-44.2] in the ADT alone arm and 39 months [28-52.6] in the ADT+D arm (HR: 0.8 [0.6-1.2]). Conclusions: With longer follow-up, the addition of docetaxel to ADT did not significantly improve OS in patients with hormone-naïve metastatic prostate cancer. In the retrospective analysis using aligned definition of volume of metastasis as E3805, the HVD outcomes were similar to E3805 for ADT alone and there was a non-significant 4 months increase in OS with ADT+D, in this underpowered subset. Clinical trial information: 00104715. [Table: see text]

Previous enzalutamide therapy and response to subsequent taxane therapy in metastatic castration-resistant prostate cancer

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Background: Cross-resistance between taxanes and androgen receptor axis targeted agents is a matter of debate in metastatic castration-resistant prostate cancer (mCRPC). Preclinical data about response to taxanes after prior enzalutamide suggest some level of cross-resistance (van Soest et al, Eur J Cancer 2013) though this was not confirmed in other models (Al Nakouzi N, Eur Urol 2014). The first objective of this study was to assess the impact of previous enzalutamide therapy on the efficacy of subsequent taxane-based chemotherapy. The second objective was to investigate the prognosis of patients when chemotherapy was initiated in enzalutamide-pretreated patients. Methods: Data from 96 enzalutamide- and placebo-treated patients enrolled in the Prevail phase III trial were retrospectively collected from 14 centers in France. Changes in prostate specific antigen (PSA) levels, progression free survival (PFS) and RECIST criteria v 1.1 were used to determine the activity of docetaxel (n=89) or cabazitaxel (n=7) treatment. The Halabi model was used to predict survival probabilities for the enzalutamide- or placebo-pretreated patients when chemotherapy was initiated (Halabi et al, J Clin Oncol 2014). Results: Overall, 96 patients were included in this analysis (58 in the placebo arm vs. 38 in enzalutamide arm). PSA response to taxanes (defined as a decline of ≥50% from baseline) was marginally lower in enzalutamide-vs. placebo-pretreated patients (34% vs. 53%, p=0.10). PSA response in enzalutamide-pretreated patients was not different from that observed with docetaxel given every 3 weeks in TAX 327 trial (Tannock et al, NEJM 2004) (45%, p=0.20, binomial test). Median PFS and objective response rates were similar between the two groups (4.8m vs 6.7 m;p=0.14 and 45% vs 43%;p=0.83 respectively). Halabi score was well-balanced between the two groups (p=0.30). Conclusions: Taxanes retain efficacy in enzalutamide-pretreated mCRPC. At the time of first-line taxane-based chemotherapy initiation, the prognosis of enzalutamide-treated patients according to the Halabi score was not different from that of enzalutamide-naïve patients.

Improving the pre-screening of eligible patients in order to increase enrollment in cancer clinical trials

BACKGROUND

The performance of randomized controlled trials (RCTs) is often hindered by recruitment difficulties. This study aims to explore the pre-screening phase of four prostate cancer RCTs to identify the impact of a systematic pre-selection of eligible patients for RCT recruitment.

METHODS

The pre-screening of four RCTs opened at the Comprehensive Cancer Center in Rennes was analyzed retrospectively (French Genitourinary Tumor Group (GETUG) 14, 15, 16, and 17). Data were extracted from electronic multidisciplinary cancer (MDC) reports and manually completed by physicians and medical secretaries. These data were the main source of information for clinicians to discuss treatment alternatives during MDC sessions. The pre-screening decisions made by the clinicians during these MDC meetings were compared with those made after a systematic review of the MDC reports by a clinical research assistant (CRA). Any inconsistencies in decisions between the CRA and the MDC physicians were corrected by the principal investigator (PI).

RESULTS

The pre-screening rate was 9.1% during the MDC meetings, while it was estimated to be 12.9% after the final review by the PI, and 29% after the systematic review by the CRA. The study showed that 77% and 67% of the MDC reports did not mention clinical and pathological Tumor, lymph node and metastasis classification of malignant tumors (TNM) staging, respectively, and that 35 of the CRA's 47 proposals rejected by the PI concerned implicit information (not specified in the MDC reports). Only one patient was proposed by the PI, and none by the CRA.

CONCLUSIONS

These results confirm that pre-screening could be improved by a systematic review of the medical reports. They also highlight the fact that missing data in electronic MDC reports leads to over-enrollment of non-eligible patients, but not to over-exclusion of eligible patients. Thus, our study confirms the potential gain in using semi-automated pre-selection of MDC reports, in order to avoid missing out on patients eligible for RCTs.

TRIAL REGISTRATION

The trials evaluated in this study were previously registered with clinicaltrials.gov (registration number: NCT00104741 on 3 March 2005; NCT00104715 on 3 March 2005; NCT00423475 on 16 January 2007; and NCT00667069 on 24 April 2008).

Prognostic Factors for Survival in Noncastrate Metastatic Prostate Cancer: Validation of the Glass Model and Development of a Novel Simplified Prognostic Model

BACKGROUND

The Glass model developed in 2003 uses prognostic factors for noncastrate metastatic prostate cancer (NCMPC) to define subgroups with good, intermediate, and poor prognosis.

OBJECTIVE

To validate NCMPC risk groups in a more recently diagnosed population and to develop a more sensitive prognostic model.

DESIGN, SETTING, AND PARTICIPANTS

NCMPC patients were randomized to receive continuous androgen deprivation therapy (ADT) with or without docetaxel in the GETUG-15 phase 3 trial. Potential prognostic factors were recorded: age, performance status, Gleason score, hemoglobin (Hb), prostate-specific antigen, alkaline phosphatase (ALP), lactate dehydrogenase (LDH), metastatic localization, body mass index, and pain.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

These factors were used to develop a new prognostic model using a recursive partitioning method. Before analysis, the data were split into learning and validation sets. The outcome was overall survival (OS).

RESULTS AND LIMITATIONS

For the 385 patients included, those with good (49%), intermediate (29%), and poor (22%) prognosis had median OS of 69.0, 46.5 and 36.6 mo (p=0.001), and 5-yr survival estimates of 60.7%, 39.4%, and 32.1%, respectively (p=0.001). The most discriminatory variables in univariate analysis were ALP, pain intensity, Hb, LDH, and bone metastases. ALP was the strongest prognostic factor in discriminating patients with good or poor prognosis. In the learning set, median OS in patients with normal and abnormal ALP was 69.1 and 33.6 mo, and 5-yr survival estimates were 62.1% and 23.2%, respectively. The hazard ratio for ALP was 3.11 and 3.13 in the learning and validation sets, respectively. The discriminatory ability of ALP (concordance [C] index 0.64, 95% confidence interval [CI] 0.58-0.71) was superior to that of the Glass risk model (C-index 0.59, 95% CI 0.52-0.66). The study limitations include the limited number of patients and low values for the C-index.

CONCLUSION

A new and simple prognostic model was developed for patients with NCMPC, underlying the role of normal or abnormal ALP.

PATIENT SUMMARY

We analyzed clinical and biological factors that could affect overall survival in noncastrate metastatic prostate cancer. We showed that normal or abnormal alkaline phosphatase at baseline might be useful in predicting survival.

Glandular metastasis as a surrogate for long survivors in metastatic renal carcinoma

510

Background: Metastatic renal cell carcinoma (RCC) is still associated with a poor prognosis with an overall survival (OS) of 37 months, although some patients are long survivors despite a disseminated disease. The purpose of this study was to determine whether the presence of at least one glandular metastasis (GM), defined by metastasis in pancreas, thyroid, breast or adrenal contralateral, affect survival outcome in patients with metastatic clear cell RCC (cc-RCC). Methods: In this retrospective analysis, we included patients treated for GM and non GM (NGM) metastatic RCC at the Institut Paoli Calmettes (IPC), Marseille, France between January 2004 and May 2013. Two more centers provided data for GM cc-RCC. GM were authentified using CTscan and/or by histopathological analysis obtained at biopsy or at surgery. Patients were analyzed from the time of metastatic disease to last follow up or death. The purpose of this study was to analyze patients outcomes based on the presence or absence of GM. We analysed survival using a log rank test from the time of the diagnosis of GM to the death or last follow-up visit. Results: Among 180 patients analysed, 59 had GM. Median age 65.2 vs 61.8 years old, male 55% vs 72%, 90% vs 78% prior nephrectomy in GM and NGM group. GM sites were pancreas for 45.5%, adrenal 44.5%, thyroid: 10%, breast10%. GM was the only site of metastasis for 10% of pts. For GM group, 55.5% had histopathology proven RCC metastasis. The median follow up was 72 months and the median survival is 114 months (IC95% [62.9-NR.]) in GM group vs 33.2 months (IC95% [23-41.9]; p<0.0001, HR 2.7 [1.7-4.3]) in non GM group. Conclusions: This retrospective study in a rare metastatic localization finds a longer survival in patients with GM. Despite some obvious limitations, this study questions GM as a surrogate for a better prognosis in RCC. Prospective follow-up and the collection for biological and genomic markers are needed to confirm and extend our present findings.

Long-term responders to everolimus: A subgroup analysis of the sector study

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Background: Everolimus is considered as a standard of care for the second line treatment of metastatic renal cell carcinoma (mRCC). Currently no clinical or biological predictive factors are available to help physicians to choose the best second line option between everolimus or TKI. Whether correlation exists between response to first line and response to second line remains debatable. Methods: We performed a subgroup analysis of the SECTOR study, a retrospective survey of patients (pts) receiving everolimus after TKI in 26 french centers to analyse long responders to everolimus. Long-term response to everolimus was defined as progression-free >9 months. Recorded variables included: patients characteristics of first line TKI (duration, response), duration of everolimus, efficacy and toxicity as well as overall survival. Results: 164 patients in 26 french cancer centres were included in the SECTOR study between october 2008 and october 2012. All patients received everolimus as second line treatment. Median age was 64.6 y.o, main histological subtype was clear-cell carcinoma (92.3%). Among the whole study cohort, we identified 30 patients (21%) as long-term responders (ranging from 9 to 33 months). Analysis of this patient population is ongoing and will be presented at the meeting. Correlation between long response and prognostic factors, as well as response to first TKI will be determined. Conclusions: Everolimus achieves long-term response in more than 20% of mRCC treated in second line. Prolonged treatment was relatively well tolerated without any unexpected late toxicity. Further investigations, especially biological studies, are warranted to identify predictive factors which will help physicians to identify long-term responder and choose the best second line option for mRCC patients.

Retrospective evaluation of tyrosine kinase inhibitor (TKI)-everolimus (eve) and/or TKI-eve-TKI sequences in metastatic renal cell carcinoma (mRCC): A French survey—The sector study

509

Background: In the RECORD-1 study, only 22% of the mRCC patients (pts) received eve in pure 2nd line. Thus more data in real world are needed. A retrospective French survey, on a large patient population, was designed to evaluate efficacy for the sequence TKI-eve and/or TKI-eve-TKI in mRCC. Methods: Between 10/08 and 10/12, 164 mRCC pts from 26 french centers, who progressed on initial TKI and received eve as 2nd line were recorded. In these pts, 3rd line TKI was recorded. Primary endpoint was Duration of Treatment (DT) of each sequence. Secondary endpoints were best radiological response for eve evaluated by 2 independent radiologists, tolerability, dose reduction, overall survival from the start of first TKI (OS). Patients characteristics: Amongst 164 pts, 144 pts with follow-up > 4 months since initiation of eve were evaluated, 59/144 pts received TKI-eve-TKI. Before eve initiation: median age was 65 yrs, most pts were male (70.3%), had clear cell histology (92.3%), had received sunitinib as first TKI (94.4%). Main comorbidities were: hypertension (43.8%), diabetes (15.3%), and hypercholesterolemia (19.4%). At the time of eve initiation, MSKCC classification was good (24.4%), intermediate (61.5%) or poor (14.1%). Results: median DT of eve was 4 months and 21% pts were treated >9 months with 2.9% PR and 67.6% SD by central review. Correlation between response to first TKI and eve was observed. Dose reduction of eve for toxicity was 23.2%. The most common toxicities (all grades) were: stomatitis (25.3%), PNI (13%), fatigue (40.7%), hyperglycemia (9.3%), hypercholesterolemia (17.3%) and hypertriglyceridemia (22.8%). Median duration of TKI-eve sequence was 18 months (IC95%: 15-20), and OS was 36 months (IC95%: 27-56). For TKI-eve-TKI sequence (59 pts), sorafenib was mostly used (76.3%) with dose reduction and clinical benefit rate of 26.7% and 42.2% respectively. Median DT and OS were 24 and 41 months (IC95%: 19-29; 25-57) respectively. Conclusions: In real world experience, for mRCC pts receiving TKI-eve sequence, median DT of eve is 4 months with OS of 36 months which compares favorably with RECORD1 and RECORD 3 trials respectively.

Patients' self-assessment versus investigators' evaluation in a phase III trial in non-castrate metastatic prostate cancer (GETUG-AFU 15)

BACKGROUND

Toxicity, which is a key parameter in the evaluation of cancer treatments, can be underestimated by clinicians. We investigated differences between patients and physicians in reporting adverse events of androgen deprivation therapy (ADT) with or without docetaxel in a multicentre phase III trial in non-castrate metastatic prostate cancer.

METHODS

The 385 patients included were invited to complete a 26-symptom questionnaire 3 and 6 months after the start of treatment, among which eighteen symptoms were also assessed by physicians, reported in medical records and graded using the Common Toxicity Criteria of the National Cancer Institute. Positive and negative agreements as well as Kappa concordance coefficients were computed.

FINDINGS

Data were available for 220 and 165 patients at 3 and 6 months respectively. Physicians systematically under-reported patients' symptoms. Positive agreement rates (at respectively 3 and 6 months) for the five most commonly reported symptoms were: 61.0% and 64.3% hot flushes, 50.0% and 43.6% fatigue, 29.4% and 31.1% sexual dysfunction, 24.4% and 14.4% weigh gain/loss, 16.7% and 19.3% for joint/muscle pain. For symptoms most frequently reported as disturbing or very disturbing by patients, the clinicians' failure to report them ranged from 50.8% (hot flushes) to 89.5% (joint/muscle pain) at 3 months, and from 48.2% (hot flushes) to 88.4% (joint/muscle pain) at 6 months.

INTERPRETATION

Physicians often failed to report treatment-related symptoms, even the most common and disturbing ones. Patients' self-evaluation of toxicity should be used in clinical trials to improve the process of drug assessment in oncology.

FUNDING

French Health Ministry and Institut National du Cancer (PHRC), Sanofi-Aventis, Astra-Zeneca, and Amgen.

All anti-vascular endothelial growth factor drugs can induce 'pre-eclampsia-like syndrome': a RARe study

BACKGROUND

Specific therapies that target vascular endothelial growth factor (VEGF) and its receptors have improved the survival of patients with metastatic cancers, but can induce side effects. Renal side effects (proteinuria, hypertension and renal failure) are underestimated.

METHODS

The French RARe (Reins sous traitement Anti-VEGF Registre) study collects data on patients with cancer who had a renal biopsy because of major renal side effects during treatment with anti-VEGF drugs.

RESULTS

We collected 22 renal biopsies performed 16.2±10.6 months after the beginning of treatment; of which 21 had hypertension, mean proteinuria was 2.97±2.00 g/day and mean serum creatinine, 134±117 µmol/L. Thrombotic microangiopathy (TMA) was observed in 21 biopsy specimens, sometimes associated with acute tubular necrosis (ATN; n=4). TMA histological lesions were more important than the biological signs of TMA could suggest. Patients with ATN of >20% had higher serum creatinine levels than those with only TMA (231 versus 95 µmol/L). Nephrin, podocin and synaptopodin were variably down-regulated in all renal biopsies. VEGF was down-regulated in all glomeruli.

CONCLUSION

This study underlines the importance of regular clinical and biological cardiovascular and renal checking during all anti-VEGF therapies for cancer for early detection of renal dysfunction. Collaboration between oncologists and nephrologists is essential. In such cases, renal biopsy might help in appreciating the severity of the renal lesions and after multidisciplinary discussion whether or not it is safe to continue the treatment.

mTOR inhibitors in advanced renal cell carcinomas: from biology to clinical practice

To date, oral everolimus is indicated for the treatment of patients with advanced renal cell carcinoma, whose disease has progressed on or after treatment with vascular endothelial growth factor-targeted therapy, and intravenous temsirolimus for the first-line treatment of patients with poor prognosis metastatic renal cell carcinoma. However, some factors could guide the treatment choice aiming to individualize a treatment plan. Besides the crucial issue of treatment efficacy, other factors are to be considered such as disease status, histological subtype, extent of the disease, patient-specific factors, and agent-specific factors. All of these considerations have to stay in the frame of guideline recommendations which represent evidence-based medicine. The purpose of this article is to summarize the main pharmacological and pharmacokinetic characteristics of mTOR inhibitors, and to define targeted populations according to prognostic indexes.

Identification of prognostic groups in patients with hormone-sensitive metastatic prostate cancer at the present time: An analysis of the GETUG 15 phase III trial

26

Background: Patients with upfront metastases at the time of prostate cancer (PC) diagnosis are less frequent than in the past in Western countries, but still represent 5-10% of all patients and almost one half of PC patients will eventually die of the disease. Prognostic factors (lymph node metastases/appendicular vs axial bone disease, performance status > 1, Gleason score > 8 and PSA > 65 ng/ml) have been proposed (Glass et al., 2003), leading to the definition of three subgroups with good, intermediate and poor prognosis. However, the current natural history of metastatic prostate cancer has not been well described. Methods: Patients with hormone sensitive metastatic PC were randomized to receive continuous androgen deprivation therapy (ADT) plus docetaxel (75 mg/m²/21d up to 9 cycles) and prednisone or ADT alone. Glass risk groups were used as stratification factors. Results: From October 2004 to December 2008, 385 pts were included. They were distributed into good (50%), intermediate (29%), and poor (21%) prognosis groups. The median follow up was 50 months [95% CI: 49 - 54]. The primary endpoint analysis showed no difference in overall survival (OS) (HR: 1.01 [95%CI: 0.75-1.36]) between the 2 arms but a significant PFS improvement was observed in the docetaxel group (HR: 0.75 [0.59-0.94] p=0.0147) (Gravis, ESMO 2012). The median OS in the ADT alone arm was 54 months [42-NR]. It was 69 [95% CI: 60.9-NR], 47 [95% CI: 37.7-NR, HR = 1.6] and 37 [95% CI: 28.5-58.9, HR = 2.12] months respectively in the good, intermediate, and poor prognosis groups (p=0.001) in the whole cohort. No interaction between prognosis groups and treatment was found. A detailed analysis using the Cox model will be presented. Conclusions: At the present time, median life expectancy of patients with metastatic PC seems to exceed 4 years. Subgroups with favorable or unfavorable outcome can be identified. Clinical trial information: NCT00055731.

Androgen-deprivation therapy alone or with docetaxel in non-castrate metastatic prostate cancer (GETUG-AFU 15): a randomised, open-label, phase 3 trial

BACKGROUND

Early chemotherapy might improve the overall outcomes of patients with metastatic non-castrate (ie, hormone-sensitive) prostate cancer. We investigated the effects of the addition of docetaxel to androgen-deprivation therapy (ADT) for patients with metastatic non-castrate prostate cancer.

METHODS

In this randomised, open-label, phase 3 study, we enrolled patients in 29 centres in France and one in Belgium. Eligible patients were older than 18 years and had histologically confirmed adenocarcinoma of the prostate and radiologically proven metastatic disease; a Karnofsky score of at least 70%; a life expectancy of at least 3 months; and adequate hepatic, haematological, and renal function. They were randomly assigned to receive to ADT (orchiectomy or luteinising hormone-releasing hormone agonists, alone or combined with non-steroidal antiandrogens) alone or in combination with docetaxel (75 mg/m(2) intravenously on the first day of each 21-day cycle; up to nine cycles). Patients were randomised in a 1:1 ratio, with dynamic minimisation to minimise imbalances in previous systemic treatment with ADT, chemotherapy for local disease or isolated rising concentration of serum prostate-specific antigen, and Glass risk groups. Patients, physicians, and data analysts were not masked to treatment allocation. The primary endpoint was overall survival. Efficacy analyses were done by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00104715.

FINDINGS

Between Oct 18, 2004, and Dec 31, 2008, 192 patients were randomly allocated to receive ADT plus docetaxel and 193 to receive ADT alone. Median follow-up was 50 months (IQR 39-63). Median overall survival was 58·9 months (95% CI 50·8-69·1) in the group given ADT plus docetaxel and 54·2 months (42·2-not reached) in that given ADT alone (hazard ratio 1·01, 95% CI 0·75-1·36). 72 serious adverse events were reported in the group given ADT plus docetaxel, of which the most frequent were neutropenia (40 [21%]), febrile neutropenia (six [3%]), abnormal liver function tests (three [2%]), and neutropenia with infection (two [1%]). Four treatment-related deaths occurred in the ADT plus docetaxel group (two of which were neutropenia-related), after which the data monitoring committee recommended treatment with granulocyte colony-stimulating factor. After this recommendation, no further treatment-related deaths occurred. No serious adverse events were reported in the ADT alone group.

INTERPRETATION

Docetaxel should not be used as part of first-line treatment for patients with non-castrate metastatic prostate cancer.

FUNDING

French Health Ministry and Institut National du Cancer (PHRC), Sanofi-Aventis, AstraZeneca, and Amgen.

Safety and Efficacy of Sorafenib in Renal Cell Carcinoma

This article reviews data on sorafenib use in renal cell carcinoma. Mechanisms of actions and pharmacokinetics are briefly described. Major clinical trials are presented, summarizing efficacy and safety of sorafenib. Its place in current treatment of renal cell carcinoma is discussed. Sorafenib is likely to remain one of the mainstays of RCC treatment in coming years.

A pharmacogenomic scoring system predicting median time to progression (mTTP) on sunitinib (SUN) as first-line treatment in patients (pts) with metastatic renal cell carcinoma (mRCC)

359

Background: There are no established biomarkers predicting outcome of SUN treatment in mRCC.

Methods: We assessed 30 single nucleotide polymorphisms (SNPs) in 10 genes on fresh frozen clear cell RCC nephrectomy specimens originating from pts who developed metastatic disease.

Results: We processed 79 samples. In 49 pts, normal kidney tissue adjacent to the tumor was used, in 30 pts only tumoral tissue was available. After nephrectomy and in presence of synchronous or metachronous metastasis, all pts received SUN as 1st line treatment. We observed associations between several SNPs and mTTP: In the promotor region of the gene encoding for IL-8 (proangiogenic growth factor): rs4073: TT or TA versus (vs) AA variant: mTTP 12 mo vs not reached (NR) (p=0.02). In ABCB1 (involved in drug transport): rs2032582: TA or TT vs GT/GA or GG: 9 vs 16 mo (p=0.03). rs1128503: TT vs CT or CC: 9 vs 16 mo (p=0.02). In VEGFR3 (a target of SUN): rs307826 : GA vs AA: 9.3 vs 18 mo (p=0.01). rs307821 : GT vs GG: 10 vs 16 mo (p=0.08). rs448012 : CC/CG vs GG: 12 mo vs NR (p=0.02). In NR1/2 (promotor leading to increased CYP3A4 expression): rs3814055: TT vs CC/CT: 13 vs 18 mo (p=0.02). rs1054190: CC vs CT: 14 vs 20 mo (p=0.14). In PDGFR-alpha (another SUN target): rs1800812: TT vs GG/GT: 3.5 vs 16 mo (p<0.0001). A scoring system combining 7 non-overlapping SNPs was build and pts were classified in a favorable, intermediate and unfavorable SNP profile group. A link with mTTP and response rate was found, but not with established clinical prognostic scores (MSKCC).

Conclusions: SNPs in genes linked to the pharmacokinetics and -dynamics of SUN can probably predict outcome of SUN treatment in mRCC. Our results confirm in part previous observations made by other groups in pazopanib or SUN (in IL-8, VEGFR3 and NR1/2) and highlight the potential role of other SNPs (in ABCB1, NR1/2 and PDGFR). Extension of the series and univariate/multivariate validation are ongoing.

[Table: see text]