P11.19.B Bevacizumab in recurrent WHO grade 2-3 gliomas

Background

Medical management of recurrent WHO grade 2-3 (rGII/III) gliomas is not well established. Bevacizumab (BEV) is an option at malignant recurrence. Yet, very few data are available in this indication. The aim of this study is to describe clinical outcomes in patients treated with BEV.

Material and Methods

A retrospective study was conducted including patients treated by BEV for a rGII/III glioma at our institution (2011 - 2019). Data were collected from medical records. Tumor samples were reviewed according to the WHO 2016 classification. Efficacy was assessed according RANO criteria. Progression Free Survival (PFS) and Overall Survival (OS) from BEV initiation were estimated using the Kaplan-Meier method. A Cox proportional hazards model was performed to estimate Hazard Ratios with 95% Confident Intervals (CI).

Results

A total of 81 patients was included (sex ratio: 1.6 M/W, median age at diagnosis: 38). Among them, 46 patients (56.8%) had a grade 2 and 35 (43.2%) a grade 3 glioma. The histological forms were astrocytoma (grade 2 -3) IDH mutated in 27 patients (33.3%), IDHwt in 15 patients (18.5%) and oligodendroglioma (grade 2 - 3) in 13 patients (16%). Twenty-six patients were not reclassified. Previous treatment included tumor resection for all patients (second intervention in 22.2%). First-line medical treatment consisted of chemotherapy in 60.5% patients before any radiotherapy. Chemotherapy was rechallenged in 52 patients (64.2%). All patients but one received radiation therapy and 19 patients (23.5%) received a reirradiation. BEV was administered at 10 or 15mg/kilogram every 2 or 3 weeks. All patients had a contrast enhancement on MRI at baseline. Median number of BEV cycles was 7 [1-79], in association with chemotherapy in 45.7%. Partial response, stable disease and progressive disease was observed in 27.2%, 22.2% and 50.6% respectively. Median OS from BEV introduction was 7.6 months (95% CI [5.5;9.9]). Median PFS was 4.9 months (95% CI [3.7;6.1]). In univariate analysis, grade 2 (Odd Ratio (OR)=0.41, 95% CI [0.17;1.02], p=0.054), Ki67<7% (OR=0.41, 95% CI [0.15;1.21], p=0.079) and initial total surgical resection (OR=2.75, 95% CI [0.68;11.11], p=0.097) showed a trend for delayed progression. BEV was stopped for progression in 70.4%, for toxicity in 8.6% and for others reasons in 21% patients. Twenty-four patients (29.6%) discontinued BEV without progression (medical decision, BEV toxicity or patient decision). Presence of 1p19q codeletion (OR=0.24, 95% CI [0.07;0.84], p=0.023) and age ≥ 38 (OR=0.36, 95% CI [0.13;0.99], p=0.042) at diagnosis were more frequent in this sub-population. Out these of 24 patients, 8 showed survival from 3 months to 5 years without any other treatment.

Conclusion

BEV can be a good option for patients with rGII/III glioma. One third of them stopped treatment without progression, reaching a survival of several years for some of them.

Sequential first-line treatment with nab-paclitaxel/gemcitabine and FOLFIRINOX in metastatic pancreatic adenocarcinoma: GABRINOX phase Ib-II controlled clinical trial

BACKGROUND

Nab-paclitaxel/gemcitabine (AG) and FOLFIRINOX (FFX) are promising drugs in metastatic pancreatic cancer (MPC). This study evaluated a new first-line sequential treatment (AG followed by FFX) in MPC that might overcome resistance to primary therapy and delay tumor progression.

PATIENTS AND METHODS

Patients with histologically/cytologically confirmed MPC were included in a multicentric trial receiving AG (day 1, 8 and 15) followed by FFX (day 29 and 43). In phase Ib, three dose-levels were tested for maximum tolerated dose (MTD) and recommended phase II dose. In phase II, the main outcome was the objective response rate (ORR) and secondarily safety, progression-free survival (PFS) and overall survival (OS).

RESULTS

In phase Ib, we included 33 patients (31 assessable) of median age 61.0 years (range 42-75 years) and represented by 54.8% males. Five dose-limiting toxicities were reported without any death. The main grade 3/4 toxicities were neutropenia with spontaneous resolution (35.5%/32.3%), venous thromboembolism (grade 3: 22.6%) and thrombopenia (grade 3: 29.0%), while the MTD was not reached. In phase II, we included 58 patients of median age 60 years (range 34-72 years), 50% males and with Eastern Cooperative Oncology Group stage score 0 and 1 of 37.9% and 62.1%, respectively. They received a median of 4 (1-9) cycles in 8.5 months (0.5-19.8 months). The ORR was 64.9% [95% confidence interval (CI) 51.1% to 77.1%], and neurotoxicity was remarkably low. The main grade 3-4 toxicities were venous thromboembolism, thrombopenia, neutropenia/febrile neutropenia, nausea, diarrhea, weight loss and asthenia without any death. Tumor response was complete in 3.5% and partial in 61.4%, while disease was stable in 19.3% and progressive in 15.8% of patients. The median PFS was 10.5 months (95% CI 6.0-12.5 months) and median OS was 15.1 months (95% CI 10.6-20.1 months).

CONCLUSION

Sequential AG and FFX showed acceptable toxicity as first-line treatment with no limiting neurotoxicity, while high response rate and survival justify randomized trials.

Optimal biological dose: a systematic review in cancer phase I clinical trials

BACKGROUND

Classical phase 1 dose-finding designs based on a single toxicity endpoint to assess the maximum tolerated dose were initially developed in the context of cytotoxic drugs. With the emergence of molecular targeted agents and immunotherapies, the concept of optimal biological dose (OBD) was subsequently introduced to account for efficacy in addition to toxicity. The objective was therefore to provide an overview of published phase 1 cancer clinical trials relying on the concept of OBD.

METHODS

We performed a systematic review through a computerized search of the MEDLINE database to identify early phase cancer clinical trials that relied on OBD. Relevant publications were selected based on a two-step process by two independent readers. Relevant information (phase, type of therapeutic agents, objectives, endpoints and dose-finding design) were collected.

RESULTS

We retrieved 37 articles. OBD was clearly mentioned as a trial objective (primary or secondary) for 22 articles and was traditionally defined as the smallest dose maximizing an efficacy criterion such as biological target: biological response, immune cells count for immunotherapies, or biological cell count for targeted therapies. Most trials considered a binary toxicity endpoint defined in terms of the proportion of patients who experienced a dose-limiting toxicity. Only two articles relied on an adaptive dose escalation design.

CONCLUSIONS

In practice, OBD should be a primary objective for the assessment of the recommended phase 2 dose (RP2D) for a targeted therapy or immunotherapy phase I cancer trial. Dose escalation designs have to be adapted accordingly to account for both efficacy and toxicity.

Handling informative dropout in longitudinal analysis of health-related quality of life: application of three approaches to data from the esophageal cancer clinical trial PRODIGE 5/ACCORD 17

Background

Health-related quality of life (HRQoL) has become a major endpoint to assess the clinical benefit of new therapeutic strategies in oncology clinical trials. Typically, HRQoL outcomes are analyzed using linear mixed models (LMMs). However, longitudinal analysis of HRQoL in the presence of missing data remains complex and unstandardized. Our objective was to compare the modeling alternatives that account for informative dropout.

Methods

We investigated three alternative methods—the selection model (SM), pattern-mixture model (PMM), and shared-parameters model (SPM)—in relation to the LMM. We first compared them on the basis of methodological arguments highlighting their advantages and drawbacks. Then, we applied them to data from a randomized clinical trial that included 267 patients with advanced esophageal cancer for the analysis of four HRQoL dimensions evaluated using the European Organisation for Research and Treatment of Cancer (EORTC) QLQ-C30 questionnaire.

Results

We highlighted differences in terms of outputs, interpretation, and underlying modeling assumptions; this methodological comparison could guide the choice of method according to the context. In the application, none of the four models detected a significant difference between the two treatment arms. The estimated effect of time on HRQoL varied according to the method: for all analyzed dimensions, the PMM estimated an effect that contrasted with those estimated by the SM and SPM; the LMM estimated effects were confirmed by the SM (on two of four HRQoL dimensions) and SPM (on three of four HRQoL dimensions).

Conclusions

The PMM, SM, or SPM should be used to confirm or invalidate the results of LMM analysis when informative dropout is suspected. Of these three alternative methods, the SPM appears to be the most interesting from both theoretical and practical viewpoints.

Trial registration

This study is registered with ClinicalTrials.gov, number NCT00861094.

GUIP1: a R package for dose escalation strategies in phase I cancer clinical trials

BACKGROUND

The main objective of phase I cancer clinical trials is to identify the maximum tolerated dose, usually defined as the highest dose associated with an acceptable level of severe toxicity during the first cycle of treatment. Several dose-escalation designs based on mathematical modeling of the dose-toxicity relationship have been developed. The main ones are: the continual reassessment method (CRM), the escalation with overdose control (EWOC) method and, for late-onset and cumulative toxicities, the time-to-event continual reassessment method (TITE-CRM) and the time-to-event escalation with overdose control (TITE-EWOC) methods. The objective of this work was to perform a user-friendly R package that combines the latter model-guided adaptive designs.

RESULTS

GUIP1 is an R Graphical User Interface for dose escalation strategies in Phase 1 cancer clinical trials. It implements the CRM (based on Bayesian or maximum likelihood estimation), EWOC and TITE-CRM methods using the dfcrm and bcrm R packages, while the TITE-EWOC method has been specifically developed. The program is built using the TCL/TK programming language, which can be compiled via R software libraries (tcltk, tkrplot, tcltk2). GUIP1 offers the possibility of simulating and/or conducting and managing phase I clinical trials in real-time using file management options with automatic backup of study and/or simulation results.

CONCLUSIONS

GUIP1 is implemented using the software R, which is widely used by statisticians in oncology. This package simplifies the use of the main model-based dose escalation methods and is designed to be fairly simple for beginners in R. Furthermore, it offers multiple possibilities such as a full traceability of the study. By including multiple innovative adaptive methods in a free and user-friendly program, we hope that GUIP1 will promote and facilitate their use in designing future phase I cancer clinical trials.

Clinical utility of circulating DNA analysis for rapid detection of actionable mutations to select metastatic colorectal patients for anti-EGFR treatment

Background

While tumor-tissue remains the 'gold standard' for genetic analysis in cancer patients, it is challenged with the advent of circulating cell-free tumor DNA (ctDNA) analysis from blood samples. Here, we broaden our previous study on the clinical validation of plasma DNA in metastatic colorectal cancer patients, by evaluating its clinical utility under standard management care.

Patients and methods

Concordance and data turnaround-time of ctDNA when compared with tumor-tissue analysis were studied in a real-time blinded prospective multicenter clinical study (n = 140 metastatic colorectal patients). Results are presented according to STARD criteria and were discussed in regard with clinical outcomes of patients.

Results

Much more mutations were found by ctDNA analysis: 59%, 11.8% and 14.4% of the patients were found KRAS, NRAS and BRAF mutant by ctDNA analysis instead of 44%, 8.8% and 7.2% by tumor-tissue analysis. Median tumor-tissue data turnaround-time was 16 days while 2 days for ctDNA analysis. Discordant samples analysis revealed that use of biopsy, long delay between tumor-tissue and blood collection and resection of the tumor at time of blood draw, tumor site, or type of tissue analyzed seem to affect concordance. Altogether, the clinical data with respect to the anti-epidermal growth factor receptor response (RAS status) and the prognosis (BRAF status) of those discordant patients do not appear contradictory to the mutational status as determined by plasma analysis. Lastly, we present the first distribution profile of the RAS and BRAF hotspot mutations as determined by ctDNA analysis (n = 119), revealing a high proportion of patients with multiple mutations (45% of the population and up to 5 mutations) and only 24% of WT scored patients for both genes. Mutation profile as determined from ctDNA analysis with using various detection thresholds highlights the importance of the test sensitivity.

Conclusion

Our study showed that ctDNA could replace tumor-tissue analysis, and also clinical utility of ctDNA analysis by considerably reducing data turnaround time.

Antibody targeting of claudin-1 as a potential colorectal cancer therapy

BACKGROUND

Metastatic colorectal cancer (mCRC) is one of the major causes of cancer-related death. Despite the substantial progress in mCRC management, it remains important to identify new therapeutic options and biological markers for personalized medicine. Here, we investigated the expression of claudin-1 (CLDN1), a major tight junction transmembrane protein, in the different colorectal cancer (CRC) molecular subtypes and then assessed the anti-tumor effect of a new anti-CLDN1 monoclonal antibody (mAb).

METHODS

Gene expression profiling and immunochemistry analysis of normal and tumor tissue samples from patients with stage IV CRC were used to determine CLDN1 gene expression. Then, the 6F6 mAb against CLDN1 extracellular part was generated. Its effect on CRC cell cycle, proliferation, survival and migration was assessed in vitro, using a 3D cell culture system, flow cytometry, clonogenic and migration assays. In vivo, 6 F6 mAb efficacy was evaluated in nude mice after subcutaneous xenografts or intrasplenic injection of CRC cells.

RESULTS

Compared with normal mucosa where it was almost exclusively cytoplasmic, in CRC samples CLDN1 was overexpressed (p < 0.001) and mainly localized at the membrane. Moreover, it was differentially expressed in the various CRC molecular subtypes. The strongest expressions were found in the consensus molecular subtype CMS2 (p < 0.001), the transit-ampliflying (p < 0.001) and the C5 subtypes (p < 0.001). Lower CLDN1 expression predicted a better outcome in the molecular subtypes C3 and C5 (p = 0.012 and p = 0.004, respectively). CLDN1 targeting with the 6 F6 mAb led to reduction of survival, growth and migration of CLDN1-positive cells. In preclinical mouse models, the 6F6 mAb decreased tumor growth and liver metastasis formation.

CONCLUSION

Our data indicate that CLDN1 targeting with an anti-CLDN1 mAb results in decreased growth and survival of CRC cells. This suggests that CLDN1 could be a new potential therapeutic target.

Molecular subtypes of metastatic colorectal cancer are associated with patient response to irinotecan-based therapies

BACKGROUND

Currently, metastatic colorectal cancer is treated as a homogeneous disease and only RAS mutational status has been approved as a negative predictive factor in patients treated with cetuximab. The aim of this study was to evaluate if recently identified molecular subtypes of colon cancer are associated with response of metastatic patients to first-line therapy.

PATIENTS AND METHODS

We collected and analysed 143 samples of human colorectal tumours with complete clinical annotations, including the response to treatment. Gene expression profiling was used to classify patients in three to six classes using four different molecular classifications. Correlations between molecular subtypes, response to treatment, progression-free and overall survival were analysed.

RESULTS

We first demonstrated that the four previously described molecular classifications of colorectal cancer defined in non-metastatic patients also correctly classify stage IV patients. One of the classifications is strongly associated with response to FOLFIRI (P=0.003), but not to FOLFOX (P=0.911) and FOLFIRI + Bevacizumab (P=0.190). In particular, we identify a molecular subtype representing 28% of the patients that shows an exceptionally high response rate to FOLFIRI (87.5%). These patients have a two-fold longer overall survival (40.1 months) when treated with FOLFIRI, as first-line regimen, instead of FOLFOX (18.6 months).

CONCLUSIONS

Our results demonstrate the interest of molecular classifications to develop tailored therapies for patients with metastatic colorectal cancer and a strong impact of the first-line regimen on the overall survival of some patients. This however remains to be confirmed in a large prospective clinical trial.

Abstract P3-05-06: Prognostic value of androgen receptor and FOXA1 co-expression in non-metastatic triple-negative breast cancer

Background

Androgen receptor (AR) is expressed in 8-53% of triple negative breast cancer (TNBC). Its prognostic value in this subgroup is controverted. FOXA1 is essential for expression of 50% of estrogen receptor (ER)–related genes. Microarray studies identified the subgroup of molecular apocrine or luminal androgen receptor tumors that express AR and luminal genes including FOXA1 but nor ER. Preclinical data suggested that FOXA1 may direct AR to sites normally occupied by ER in luminal tumors, inducing an estrogen-like gene program stimulating proliferation. We have already shown that TNBC with AR/FOXA1 co-expression seem to behave like luminal tumors.

We aimed at evaluating co-expression AR/FOXA1-associated profiles and its prognostic value in a large retrospective series of patients with non-metastatic TNBC with a long follow-up.

Patients and methods

AR and FOXA1 expression were evaluated by immunohistochemistry in tissue microarrays of 300 patients with non-metastatic TNBC treated in our center between 2002 and 2012. Positivity threshold was set at ≥10% staining.

Results

Median age was 57.7 years (range 28.5-98). 46.2% of tumors were classified T1 and 64% pN0. We found 83.2% of ductal carcinomas, 5% of lobular carcinomas and 11.8% of other histological types. SBR grade 1-2 represented 21.4%. A basal-like phenotype (cytokeratins 5/6 and/or EGFR+) was observed in 63.7% of cases. In 161 evaluable patients, a PIKCA mutation (exon 9 or 20) was observed in 16.2% of cases. In 124 evaluable patients, a deletion of PTEN was observed in 25% of cases. Adjuvant chemotherapy was delivered in 74.5% of patients.

37.7% of patients had AR+ tumors and 29.7% had AR+ and FOXA1+ tumors. AR+/FOXA1+ tumors were more frequently: found in older patients (p&lt;0.001), lobular (p&lt;0.001) and of lower nuclear grade (p&lt;0.001) than others TNBC. AR+/FOXA1+ tumors exhibited less frequently basal-like phenotype (45.8%) than AR+/FOXA1- (77.3%) and AR-/FOXA1- (70.1%) tumors (p&lt;0.001). AR+/FOXA1+ tumors exhibited more frequently PIK3CA mutations (35.8%) than AR+/FOXA1- (16.7%) and AR-/FOXA1- (5.9%) tumors (p&lt;0.001). AR+/FOXA1+ tumors exhibited less frequently PTEN deletion (6.8% vs 16.7% for AR+/FOXA1- vs 36.5% for AR-/FOXA1- tumors, respectively, p=0.001).

With a median follow-up of 5.5 years, recurrence-free survival (RFS) was significantly lower for patients with AR+/FOXA1+ tumors (p=0.046). 3-years RFS were 84.2% and 85.3% for AR+/FOXA1+ and the others TNBC, respectively. 5-years RFS were 67.4% and 79.4% for AR+/FOXA1+ and the others TNBC, respectively. Tumor size, nodal status and adjuvant chemotherapy were also statistically correlated to RFS. Tumor size, nodal status, histology and adjuvant chemotherapy were significantly associated with overall survival.

Conclusions

In this large series, almost 30% of TNBC had an AR/FOXA1 co-expression with distinct clinicopathological characteristics and a worse outcome than others TNBC with higher risk of late recurrences. These biomarkers could be useful to identify a subgroup of TNBC and could have therapeutic implications: anti-androgen are under investigation, FOXA1 could be another therapeutic target and PI3K inhibitors should be evaluated in this specific subgroup, alone or in association with anti-androgens.

Citation Format: Guiu S, Charon-Barra C, Mollevi C, Boissiere F, Crapez E, Chartron E, Lamy P-J, Gutowski M, Bourgier C, Romieu G, Simony-Lafontaine J, Jacot W. Prognostic value of androgen receptor and FOXA1 co-expression in non-metastatic triple-negative breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P3-05-06.

Abstract P5-06-08: BRCA1 promoter hypermethylation, but not BRCA1 expression, is associated with basal-like features and good prognosis in triple negative breast cancer

Purpose: BRCA1 gene mutation is closely associated with familial hereditary breast cancer. Decreased expression of BRCA1 could be detected in certain types of sporadic breast cancer without BRCA1 mutations. Aberrant hypermethylation of DNA promoter CpG islands is one of the mechanisms by which tumor suppressor gene expression and function could be lost. We investigated BRCA1 methylation status and BRCA1 immunohistochemistry (IHC) expression and their clinic-pathological significance in triple negative breast cancers (TNBC).

Patients and methods: We analyzed BRCA1 promoter hypermethylation using a methylation specific PCR assay and BRCA1 IHC expression using the MS110 monoclonal antibody and Garg and Meisel scoring classification. Their clinicopathological and prognostic implications were analyzed in a TMA of TNBC samples from European patients.

Results: To date, 123 TNBC have been analyzed. 25 tumors (20%) presented a BRCA1 promoter hypermethylation. BRCA1 IHC expression was retained, equivocal and lost in 73 (59%), 17 (14%) and 33 (27%) cases respectively. No significant correlation was found between promoter hypermethylation and protein expression (p=0.28). A significant association was found between promoter hypermethylation and basal staining (CK5/6 and/or EGFR IHC staining), while using either a 10% or 1% cut-off for basal definition (p= 0.04 and 0.03, respectively). No significant association was found between BRCA1 expression and a basal phenotype. With a median follow-up of 6.3 years (range [0.01 – 11.8]), 35 relapses and deaths occurred (71.2% 5-years RFS and 77.8 5-years OS). RFS was significantly associated with T and N stage, and a trend was seen for a better prognosis of BRCA1 promoter hypermethylated tumors (5-years RFS: 84% vs. 68%, p=0.07). OS was significantly associated with T and N stage, and adjuvant chemotherapy.

Conclusion: BRCA1 promoter hypermethylation is associated with basal-like features and seems to be associated with a better prognosis in TNBC. BRCA1 IHC expression is not a good surrogate marker for evaluation of the methylation status of the tumors, and did not appear associated with prognosis in our series. The data will be updated for the meeting in term of number of analyzed tumors in order to strengthen the statistical analysis.

Citation Format: Jacot W, Simony-Lafontaine J, Mollevi C, Boissierre F, Lopez-Crapez E, Chartron E, Lamy P-J, Guiu S. BRCA1 promoter hypermethylation, but not BRCA1 expression, is associated with basal-like features and good prognosis in triple negative breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-06-08.

Prognostic factors in relapsed or refractory male germ cell tumors: Results from an international study of 1,593 patients

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Background: The results of salvage treatment in male patients (pts) with relapsed or refractory germ-cell tumors (rr-GCT) depend considerably on prognostic factors. However, individual factors are not broadly accepted. Methods: Between 09/2007 and 12/2008 data on 1984 pts with rr-GCT were collected from 38 centers/groups worldwide. Inclusion criteria were (1) First line treatment for metastatic GCT after January 1, 1990; (2) Cisplatin and etoposide as part of first-line regimens; (3) No first-line high-dose chemotherapy (HDCT); (4) Relapse or progression after first-line treatment; (5) Cisplatin- based conventional-dose regimens or HDCT as salvage treatment. Data were centrally reviewed and checked for consistency. The primary endpoint was progression-free survival (PFS). Prognostic factors were identified using Cox multivariate regression analysis. Results: Overall 1593 (80%) pts fulfilled the strict inclusion criteria. Salvage treatment given as consolidation of first-line treatment in patients without progression was the most frequent cause of exclusion. Median follow-up was 58 months (range 1 to 206 months). Three-year PFS for the entire group was 38% (95% CI: 35%-40%), the overall survival was 51% (95% CI: 48%-54%). Multivariate analysis on a randomly selected 2/3 training dataset identified the following variables as the most significant ones for PFS: see Table . Cisplatin-refractory or absolute refractory disease was a confounding factor for response to first-line treatment. Conclusions: This preliminary analysis of a large dataset allowed the identification of important prognostic factors in rr- GCT. A prognostic score for first-salvage treatment based on the results of a final analysis will be presented.

[Table: see text]

No significant financial relationships to disclose.