EPSILoN: A Prognostic Score for Immunotherapy in Advanced Non-Small-Cell Lung Cancer: A Validation Cohort

BACKGROUND

Beyond programmed death ligand 1 (PD-L1), no other biomarkers for immunotherapy are used in daily practice. We previously created EPSILoN (Eastern Cooperative Oncology Group performance status (ECOG PS), smoking, liver metastases, lactate dehydrogenase (LDH), neutrophil-to-lymphocyte ratio (NLR)) score, a clinical/biochemical prognostic score, in 154 patients treated with second/further-line immunotherapy. This study's aim was to validate EPSILoN score in a different population group.

METHODS

193 patients were included at National Cancer Institute of Milan (second-line immunotherapy, 61%; further-line immunotherapy, 39%). Clinical/laboratory parameters such as neutrophil-to-lymphocyte ratio and lactate dehydrogenase levels were collected. Kaplan-Meier and Cox hazard methods were used for survival analysis.

RESULTS

Overall median progression-free survival and median overall survival were 2.3 and 7.6 months, respectively. Multivariate analyses for Progression-Free Survival (PFS) identified heavy smokers (hazard ratio (HR) 0.71, p = 0.036) and baseline LDH < 400 mg/dL (HR 0.66, p = 0.026) as independent positive factors and liver metastases (HR 1.48, p = 0.04) and NLR ≥ 4 (HR 1.49, p = 0.029) as negative prognostic factors. These five factors were included in the EPSILoN score which was able to stratify patients in three different prognostic groups, high, intermediate and low, with PFS of 6.0, 3.8 and 1.9 months, respectively (HR 1.94, p < 0.001); high, intermediate and low prognostic groups had overall survival (OS) of 24.5, 8.9 and 3.4 months, respectively (HR 2.40, p < 0.001).

CONCLUSIONS

EPSILoN, combining five baseline clinical/blood parameters (ECOG PS, smoking, liver metastases, LDH, NLR), may help to identify advanced non-small-cell lung cancer (aNSCLC) patients who most likely benefit from immune checkpoint inhibitors (ICIs).

Impact of age and gender on the safety and efficacy of chemotherapy plus bevacizumab in metastatic colorectal cancer: a pooled analysis of TRIBE and TRIBE2 studies

BACKGROUND

The phase III TRIBE and TRIBE2 studies randomized metastatic colorectal cancer patients to first-line FOLFOXIRI/bevacizumab or a doublet (FOLFIRI or FOLFOX)/bevacizumab. The studies demonstrated a significant benefit from the triplet at the price of an increased incidence of chemotherapy-related adverse events (AEs). In both trials, males and females aged between 18 and 70 years with ECOG PS ≤2 and between 71 and 75 years with ECOG PS = 0 were eligible. We investigated the effect of FOLFOXIRI/bevacizumab versus doublets/bevacizumab according to age and gender.

PATIENTS AND METHODS

Subgroup analyses according to age (<70 versus 70-75 years) and gender were carried out for overall response rate (ORR), progression-free survival (PFS), and AE rates.

RESULTS

Of 1187 patients, 1005 (85%) were aged <70 years and 182 (15%) 70-75 years; 693 (58%) were males and 494 (42%) females. There was no evidence of interaction between age or gender and the benefit provided by the intensification of the upfront chemotherapy in terms of ORR and PFS, or the increased risk of experiencing G3/4 AEs. Elderly patients and females experienced higher rates of overall G3/4 AEs (73% versus 60%, P < 0.01 and 69% versus 57%, P < 0.01, respectively). Notably, in the FOLFOXIRI/bevacizumab subgroup, G3/4 diarrhea and febrile neutropenia occurred in 27% and 16% of elderly patients, respectively, while females reported high incidences of any grade nausea (67%) and vomiting (50%).

CONCLUSIONS

The improvements in terms of ORR and PFS of FOLFOXIRI/bevacizumab versus doublets/bevacizumab are independent of gender and age, with a similar relative increase in AEs among elderly patients and females. Initial dose reductions and possibly primary G-CSF prophylaxis should be recommended for patients between 70 and 75 years old treated with FOLFOXIRI/bevacizumab, and a careful management of antiemetic prophylaxis should be considered among females.

Atypical RAS Mutations in Metastatic Colorectal Cancer

PURPOSE

To describe the clinical and molecular features of metastatic colorectal cancers (mCRCs) bearing uncommon atypical RAS (At-RAS) mutations at codons other than 12, 13, 59, 61, 117, and 146.

MATERIALS AND METHODS

By exploiting five next-generation sequencing sources (Italian collaboration, Memorial Sloan Kettering Cancer Center, Samsung Medical Center, the Biomarker Research for Anti-EGFR Monoclonal Antibodies by Comprehensive Cancer Genomics (BREAC) study, and the Foundation Medicine database), we retrieved 175 At-RAS mutated cases. Molecular data were obtained from 163 samples from Memorial Sloan Kettering Cancer Center and the Foundation Medicine database. Clinical data were available for 27 At-RAS-positive and 467 negative cases from the Italian collaboration, Memorial Sloan Kettering Cancer Center, Samsung Medical Center, and the BREAC study.

RESULTS

At-RAS mutations were identified in 163 (0.9%) of 18,270 mCRCs. Among 133 with evaluable microsatellite instability status, 11 (8%) were microsatellite instability high. POLE exonuclease domain mutations had higher frequency (7%) than expected and were found only in microsatellite-stable tumors with high tumor mutational burden (TMB). Overall, 17% (28 of 163) of At-RAS cases had TMB greater than 20 mutations/Mb. Co-occurring typical RAS/BRAF V600E mutations and NF1 mutations, presumed to cause RAS activation, were found in 30% and 12% of samples, respectively (up to 43% and 50%, respectively, in TMB-high samples). Patients with RAS/BRAF wild-type mCRC achieved a median overall survival (OS) of 42.1 months, whereas those harboring isolated At-RAS, typical RAS, or BRAF V600E mutations showed a median OS of 32.3, 30.0, and 17.9 months, respectively (P < .001). No significant OS difference (P = .240) was found between patients with At-RAS versus typical RAS-mutated mCRC. Only one of six patients evaluable for primary resistance to anti-epidermal growth factor receptors achieved tumor response.

CONCLUSION

At-RAS mutations may be a marker for RAS pathway activation and can be associated with high co-occurrence of POLE exonuclease domain mutations.

Capecitabine and Temozolomide versus FOLFIRI in RAS-Mutated, MGMT-Methylated Metastatic Colorectal Cancer

PURPOSE

To determine whether second-line therapy with capecitabine and temozolomide was superior to irinotecan, leucovorin, and fluorouracil (FOLFIRI) in patients with RAS-mutated, methyl-guanine methyltransferase (MGMT)-methylated metastatic colorectal cancer (mCRC).

PATIENTS AND METHODS

In this randomized, phase II trial, we enrolled patients with RAS-mutated, MGMT-methylated mCRC after failure of oxaliplatin-based regimen. Patients with centrally confirmed MGMT methylation were stratified by first-line progression-free survival (PFS) and prior bevacizumab and randomized to either capecitabine plus temozolomide (arm A, CAPTEM) or FOLFIRI (arm B). The primary endpoint was PFS analyzed on intention-to-treat basis, with 90% power and one-sided significance level of 0.05 to detect an increase of median time from 2 months in arm B to 4 months in arm A.

RESULTS

Between November 2014 and May 2019, 86 patients were randomly assigned to arm A (n = 43) or arm B (n = 43). After a median follow-up of 30.5 months (interquartile range, 12.2-36.3), 79 disease progression or death events occurred. Superiority of arm A was not demonstrated (one-sided P = 0.223). Progression-free survival and overall survival were 3.5 (2.0-5.0) and 9.5 (8.2-25.8) in arm A versus 3.5 (2.3-6.1) and 10.6 (8.5-20.8) in arm B [HR = 1.19 (0.82-1.72) and HR = 0.97 (0.58-1.61)], respectively. Grade ≥3 treatment-related adverse events had higher incidence in arm B versus A (47.6% vs 16.3%), and quality of life was significantly worse in arm B. Patients with positive MGMT expression by IHC did not benefit from CAPTEM.

CONCLUSIONS

Temozolomide-based therapy warrants further investigation in molecularly hyperselected subgroups.

The Landscape of Actionable Gene Fusions in Colorectal Cancer

The treatment scenario of metastatic colorectal cancer (mCRC) has been rapidly enriched with new chemotherapy combinations and biological agents that lead to a remarkable improvement in patients’ outcome. Kinase gene fusions account for less than 1% of mCRC overall but are enriched in patients with high microsatellite instability, RAS/BRAF wild-type colorectal cancer. mCRC patients harboring such alterations show a poor prognosis with standard treatments that could be reversed by adopting novel therapeutic strategies. Moving forward to a positive selection of mCRC patients suitable for targeted therapy in the era of personalized medicine, actionable gene fusions, although rare, represent a peculiar opportunity to disrupt a tumor alteration to achieve therapeutic goal. Here we summarize the current knowledge on potentially actionable gene fusions in colorectal cancer available from retrospective experiences and promising preliminary results of new basket trials.

Efficacy and safety of immunotherapy in elderly patients with non-small cell lung cancer

OBJECTIVES

Most trials with Immune Checkpoint Inhibitors (ICIs) for Non-Small Cell Lung Cancer (NSCLC) included only small subgroups of patients aged ≥65. As NSCLC is often diagnosed in patients aged ≥70, real-world data about efficacy and safety of immunotherapy (IO) in elderly patients are essential.

MATERIALS AND METHODS

We retrospectively collected data about all patients with advanced NSCLC treated with IO at our Institution between April 2013 and March 2019. The patients were stratified for age as follows: <70 year-old, 70-79 year-old, ≥80 year-old. Chi-square test was used to compare qualitative variables. Survival was estimated with Kaplan-Meier method. Log-rank test was used to compare curves. Multivariate analyses were performed with Cox model.

RESULTS

We reviewed 290 cases, with a median age of 67 (range: 29-89). Patients aged<70, 70-79 and ≥80 year-old were 180, 94 and 16, respectively. Clinical/pathological variables were uniformly distributed across age classes, except for a higher rate of males (p 0.0228) and squamous histology (p 0.0071) in the intermediate class. Response Rate (RR) was similar across age groups (p 0.9470). Median Progression Free Survival (PFS) and Overall Survival (OS) did not differ according to age (p 0.2020 and 0.9144, respectively). Toxicity was comparable across subgroups (p 0.6493). The only variables influencing outcome were performance status (PS) (p < 0.0001 for PFS, p 0.0192 for OS), number of metastatic sites (p 0.0842 for PFS, p 0.0235 for OS) and IO line (p < 0.0001 for both PFS and OS).

CONCLUSION

Advanced age was not associated to a reduced efficacy of IO in our case series. Furthermore, no toxicity concern emerged even among the eldest pts. To our opinion, ICIs should be considered irrespective of age, provided an optimal PS at baseline. Of note, IO is often the only therapeutic option applicable to these cases considering the toxicity of chemotherapy.

The Evaluation of Response to Immunotherapy in Metastatic Renal Cell Carcinoma: Open Challenges in the Clinical Practice

Immunotherapy has changed the therapeutic scenario of metastatic renal cell carcinoma (mRCC), however the evaluation of disease response to immune-checkpoint inhibitors is still an open challenge. Response evaluation criteria in solid tumors (RECIST) 1.1 criteria are the cornerstone of response assessment to anti-neoplastic treatments, but the use of anti-programmed death receptor 1 (PD1) and other immunotherapeutic agents has shown atypical patterns of response such as pseudoprogression. Therefore, immune-modified criteria have been developed in order to more accurately categorize the disease response, even though their use in the everyday clinical practice is still limited. In this review we summarize the available evidence on this topic, with particular focus on the application of immune-modified criteria in the setting of mRCC.

Developing a score system to predict therapeutic outcomes to anti-PD-1 immunotherapy in metastatic melanoma

BACKGROUND

Prognosis of patients with metastatic melanoma has improved due to the advent of antibodies targeting the programmed cell death protein-1 (PD-1). However, therapeutic outcomes from anti-PD-1 therapy widely differ among patients. Biomarkers for outcome are needed as these may influence patient selection and treatment decision.

METHODS

Data of patients with metastatic melanoma treated with anti-PD-1 were retrospectively reviewed. Baseline biochemical (serum lactate dehydrogenase [LDH] levels, complete blood count) and clinical characteristics were evaluated to identify predictors of progression-free survival (PFS) and overall survival (OS). PFS and OS were assessed using Kaplan-Meier and Cox models. The comparison of predictive power of independent predictors for response to anti-PD-1 was evaluated by receiver operating characteristic (ROC) curves.

RESULTS

Overall, 173 patients were included. Low metastases burden, normal baseline LDH levels, and high relative lymphocyte count (RLC) were associated with favorable outcomes (p < 0.01). According to ROC curves, RLC >17.5% improved survival outcomes. PFS was 3.7 and 15.8 months for patients with RLC <17.5% and >17.5%, respectively (p = 0.004); OS was 5.0 and 33.6 months for patients with RLC <17.5% and >17.5%, respectively (p < 0.001). Stratification of patients according to these variables showed that survival outcomes strongly differ in patients with 3 of 3 compared to those with 2, 1, and none of these 3 factors present (p < 0.001).

CONCLUSIONS

Metastases burden, LDH levels, and RLC are independent baseline characteristics associated with outcome in patients with melanoma receiving anti-PD-1. Further investigations are needed to clarify if evaluation of these parameters can translate into clinical strategy and apply to patient selection.

SPARC Is a New Myeloid-Derived Suppressor Cell Marker Licensing Suppressive Activities

Myeloid-derived suppressor cells (MDSC) are well-known key negative regulators of the immune response during tumor growth, however scattered is the knowledge of their capacity to influence and adapt to the different tumor microenvironments and of the markers that identify those capacities. Here we show that the secreted protein acidic and rich in cysteine (SPARC) identifies in both human and mouse MDSC with immune suppressive capacity and pro-tumoral activities including the induction of epithelial-to-mesenchymal transition (EMT) and angiogenesis. In mice the genetic deletion of SPARC reduced MDSC immune suppression and reverted EMT. Sparc^−/− MDSC were less suppressive overall and the granulocytic fraction was more prone to extrude neutrophil extracellular traps (NET). Surprisingly, arginase-I and NOS2, whose expression can be controlled by STAT3, were not down-regulated in Sparc^−/− MDSC, although less suppressive than wild type (WT) counterpart. Flow cytometry analysis showed equal phosphorylation of STAT3 but reduced ROS production that was associated with reduced nuclear translocation of the NF-kB p50 subunit in Sparc^−/− than WT MDSC. The limited p50 in nuclei reduce the formation of the immunosuppressive p50:p50 homodimers in favor of the p65:p50 inflammatory heterodimers. Supporting this hypothesis, the production of TNF by Sparc^−/− MDSC was significantly higher than by WT MDSC. Although associated with tumor-induced chronic inflammation, TNF, if produced at high doses, becomes a key factor in mediating tumor rejection. Therefore, it is foreseeable that an unbalance in TNF production could skew MDSC toward an inflammatory, anti-tumor phenotype. Notably, TNF is also required for inflammation-driven NETosis. The high level of TNF in Sparc^−/− MDSC might explain their increased spontaneous NET formation as that we detected both in vitro and in vivo, in association with signs of endothelial damage. We propose SPARC as a new potential marker of MDSC, in both human and mouse, with the additional feature of controlling MDSC suppressive activity while preventing an excessive inflammatory state through the control of NF-kB signaling pathway.

Prognostic score for second or further line immunotherapy in advanced non-small cell lung cancer (aNSCLC): An external validation

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Background: Beyond PD-L1, nowadays oncologists can only use clinical characteristics to candidate patients for immunotherapy (IO). Previously, a clinical prognostic score composed by ECOG performance status (PS), sex, histology, stage, uses of platin-based therapy at first-line (1L) and response to 1L categorized 3 different prognostic groups for patients treated with second-line (2L) chemotherapy (CHT) (Di Maio, EJC. 2010 Mar;46(4):735-43.). The aim of this study is to assess if the same score is able to discriminate the outcome of aNSCLC pts treated in 2L or further-line IO, potentially helping decision making. Methods: We recorded data of patients collected from two institutional databases: Istituto Nazionale Tumori of Milan and IRCCS Oncologico Giovanni Paolo II of Bari, Italy. Overall survival (OS) was the primary endpoint and also progression-free survival (PFS) was assessed. Prognostic score was generated, and pts were divided into 3 prognostic groups: best (B: < 5), intermediate (I:5-9), worst (W: > 9). Results: Overall, 347 pts were included in the analysis (193 from Milan and 154 from Bari). Median age was 66 years (y) (30 – 88y), most were < 70 y (67.5%), male (70.7%), smokers (79.5%) and adenocarcinoma (74.6%). ECOG PS was: 0 (23%), 1 (54.5%) and 2 (22.5%). Pts distribution was: 28%, 51% and 21% in the B, I and W groups, respectively. Median OS was 18.0 months for B group, 8.5 months for I group (HR vs B 1.83, 95%CI 1.35 – 2.47, p < 0.001) and 2.6 months for W group (HR vs B 5.77, 95%CI 3.99 – 8.33, p < 0.001). Median PFS was 3.4 months for B group, 3.7 months for I group (HR vs B 1.35, 95% CI 1.03 – 1.77, p = 0.032) and 1.9 months for W group (HR vs B 2.51. 95% CI 1.80- 3.50, p < 0.001). Similar results were obtained stratifying the model by Institution. Conclusions: This clinical prognostic score, that was generated in patients treated with second-line chemotherapy, is able to highly predict outcomes of patients treated with IO. These results demonstrated that in pre-treated aNSCLC pts, the worst category has a dismal absolute life expectancy, and probably would not benefit from any active systemic therapy (independently if CHT or IO). Perhaps for these pts best supportive care could be the best choice.

Immune-checkpoints inhibitors in metastatic non small cell lung cancer with rare histology

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Background: Immune-checkpoints inhibitors (ICIs) have clearly improved prognosis of metastatic lung squamous carcinoma and adenocarcinoma, while their benefit remains uncertain in patients (pts) with rare NSCLC histotypes (RH). The study aim was to evaluate ICIs efficacy in RH. Methods: We retrospectively collected data from consecutive metastatic NSCLC pts treated with ICIs at our Institution from 4/2013 to 12/2018. Objective response rate (ORR) and disease control rate (DCR) were assessed. Fisher’s exact test was used to compare ORR and DCR in RH versus not-RH (NRH). Univariate and multivariate survival analyses were estimated by Kaplan-Meier and Cox progression hazard models. Results: Of 268 pts, 31 (11.6%) had RH: 16 sarcomatoid, 7 pulmonary enteric adenocarcinoma, 4 large cell neuroendocrine carcinoma and 4 adenosquamous carcinoma. In RH group, median age was 67 years old (range 41-81), most were males (71%) and smokers (90.3%); ECOG PS was: 0 (16.1%), 1 (67.8%) and 2 (16.1%). PD-L1 < 1%, 1-49%, ≥50% and unknown expression were reported in 22.6%, 19.3%, 35.5% and 22.6% pts, respectively. Twelve pts received ICIs as first and 19 as second or further-line. ORR was 22.6% in RH, 20.3% in NRH (p = 0.81); DCR was 35.5% in RH, 53.1% in NRH (p = 0.08). After a median follow-up of 20 months (m) (95% CI 4.0 – 36.7 m), median progression-free survival (PFS) was 2.6 m (95% CI 1.9-3.3 m) in RH vs 2.6 m in NRH (95% CI 2.1 – 3.0 m); median overall survival (OS) was 4.6 m (95% CI 0.03-12.0 m) in RH vs 9.2 m (95% CI 7.4 – 10.9 m) in NRH. No statistically significant differences were seen between the two groups (p = 0.729 for PFS, p = 0.601 for OS). At multivariate analyses adjusted for age, sex, smoke, PS, PD-L1 status, line of therapy and histotype (RH vs NRH), only low PS and first line treatment showed better PFS and OS (p < 0.001 and p = 0.003, respectively) in overall population. Conclusions: Our analysis, limited by the small and heterogeneous RH sample size, reported no significant differences between RH and NRH in terms of ORR, DCR and survival. However, looking at OS and DCR data, RH seem to have worse outcome. Correlation between histotype and pts characteristics and survival analyses in a larger cohort of ICIs treated NSCLC pts is ongoing. Specific prospective trials are needed to evaluate ICIs role in RH.

Impact of cholesterolemia and body mass index on outcome of metastatic non small cell lung cancer treated with immunotherapy

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Background: Immunotherapy (IO) is effective against metastatic Non Small Cell Lung Cancer (mNSCLC). Nonetheless, a minority of patients (pts) gains a benefit from IO and predictive variables of response are scarcely understood. Previous retrospective studies have showed a superior outcome for obese pts and preclinical data suggest a role of lipid profile. We aimed at investigating these topics in a cohort of pts with mNSCLC. Methods: We retrospectively collected data about all consecutive pts with mNSCLC treated with IO at our Institution between 12/2017 and 12/2018. Body Mass Index (BMI) was calculated as weight/height2; pts were classified as overweight if having a BMI≥25 kg/m2. Basal Cholesterolemia (BC) was dosed between one month (mo) before and one mo after the beginning of IO, with a cut-off for normality of 200 mg/dL. Survival was estimated with Kaplan-Meier method. Cox model was used for multivariate analyses. Results: We identified 55 pts. Thirty-three had a normal baseline BMI, the remaining were overweighted. Median BC was 171.5 mg/dL (range 15-313); 14 pts had hypercholesterolemia. No correlation was evident between BMI and BC ( p .1772). Neither BMI nor BC were associated to first and best response to IO. Median Progression Free Survival (PFS) was 3.75 mos; median Overall Survival (OS) was 6.78 mos. Hypercholesterolemia was related to longer PFS (9.44 vs 3.71 mos, p .0484), confirmed at multivariate analysis ( p.0392). Both hypercholesterolemia and BMI≥25 kg/m2 were associated to longer OS (15.56 vs 5.13 mos, p.0411, and 16.67 vs 4.97 mos, p.0222, respectively), but only BMI retained significance at multivariate analysis ( p .0279). Conclusions: Hypercholesterolemia shows a positive impact on outcome of mNSCLC treated with IO. The independence of this correlation from BMI suggests the existence of a true different metabolic pathways. Moreover, overweight patients have a longer OS than those with normal BMI. This result confirms previous data on obese patients, extending the range of BMI values that are linked to a better prognosis. In conclusion, the role of metabolism and body composition in defining the benefit from IO in mNSCLC is likely multifaceted, warranting further investigation.

Exploiting DNA repair alterations in metastatic pancreatic cancer (mPAC): Is MGMT methylation a new therapeutic target?

e15770

Background: Metastatic pancreatic cancer (mPAC) has a poor prognosis, with few therapeutic options and an overall survival (OS) at 5 years < 5%. O6-methylguanine-DNA methyltransferase ( MGMT) is a key DNA repair gene, responsible of alkyl groups’ elimination from the O6-position of guanine. Its promoter methylation results in diminished DNA-repair of O6-alkylguanine adducts and enhanced sensitivity to alkylating agents, such as temozolomide (TMZ). Of note, both reductions in MGMT expression and MGMT promoter methylation are described in a variety of gastrointestinal malignancies, including colorectal cancer (CRC). Here we present data on MGMT methylation tested in mPAC pts treated at our center. Methods: Formalin-fixed paraffin-embedded (FFPE) tissue samples were examined using Next Generation Sequencing (50 genes “Hotspot Cancer Panel, Ion Torrent®” and “Oncomine BRCA Research Assay”) and PCR analysis of microsatellite instability (MSI). Furthermore, the exploratory analysis of MGMT status was performed via methyl specific PCR (EZ DNA Methylation-Gold™ KIT) to assess promoter methylation, and immunohistochemistry (IHC) was done to assess protein expression. Results: Archived FFPE tissue sections obtained from 60 pts treated at Fondazione IRCCS Istituto Nazionale dei Tumori of Milan from October 2017 to December 2018 were analyzed. 47 samples (78%) had adequate tissue for extended analyses. As expected, 44 (93%) pts had KRAS mutations, while ATM, CDKN2A mutations and microsatellite instability (MSI) were found in 3 pts (6%), respectively. MGMT promoter methylation was identified in 14 pts (29%), with low/negative MGMT protein expression in 7 (14%). Interestingly, amongst MGMT methylated pts, there were 3 (21%) BRCA1/2 somatic mutant and 1 (7%) MSI, suggesting possible genomic instability. Conclusions: MGMT is a prognostic and predictive marker in glioblastomas and there is an increasing evidence in its role in metastatic CRC, with phase II studies showing a response rate of 10% in chemorefractory pts with MGMT methylation treated with TMZ. In our single center experience, MGMT methylation was found in 29% of patients with mPAC. This data warrant further prospective confirmation, but there is definitely a growing interest in the role of MGMT methylation as a predictive and prognostic biomarker in mPAC.

Clinical impact of neutropenia and febrile neutropenia in mCRC pts treated with FOLFOXIRI/bevacizumab (bev): A pooled analysis of TRIBE and TRIBE2 studies

11591

Background: FOLFOXIRI/bev is a valid option as first-line therapy for unresectable mCRC. TRIBE and TRIBE2 trials reported better activity and efficacy of the triplet/bev when compared with doublets/bev at the price of a higher incidence of chemo-related toxicities, including neutropenia (N). Here we aim at providing a detailed description of this adverse event, including the occurrence of febrile neutropenia (FN) and the use of granulocyte-colony stimulating factors (G-CSFs), in order to estimate the clinical relevance of N during FOLFOXIRI/bev. Methods: Safety data of 1175 pts enrolled in the TRIBE and TRIBE2 studies were reviewed. The incidence of N, the incidence and severity of FN, and the use of G-CSF in the triplet/bev and in the doublets/bev arms were compared using the Chi-square or the Fisher exact test as appropriate. Results: Out of 1175 pts included in the final analysis, 586 (49.8%) were treated with FOLFOXIRI/bev. Five pts (0.8%) in the doublets/bev arms and 29 (4.9%) in the triplet/bev arms received a primary prophylaxis with G-CSF. Among other pts, 118 (20.2%) in the doublets/bev arms and 276 (49.9%) in the triplet/bev arms experienced ≥ G3 N (p < 0.001). FN occurred in 25 (4.3%) and 41 (7.4%) cases respectively (p=0.041). Out of 78 FN episodes, 4 (13.3%) out of 30 in the doublets/bev arms and 13 out of 48 (27.1%) in the triplet/bev arms were associated with a poor MASCC score (<21) (p=0.17). G-CSF was used in 1069 (10.8%) cycles, 270 (5.3%) in doublets/bev and 799 (16.6%) in triplet/bev arms. In both arms, the majority of N and FN episodes were observed in the first two months (318 ≥ G3 N episodes out of 675 (47.1%), and 54 FN episodes out of 78 (69.2%)). Conclusions: FOLFOXIRI/bev was associated with a higher risk of N and FN than doublets/bev. However, the risk of FN was lower than 10%, thus not requiring a systematic use of primary G-CSF prophylaxis. The majority of FN episodes was associated with a good MASCC score, thus having a limited clinical impact. The vast majority of FN episodes occurred in the first two months of treatment, suggesting a closer monitoring of this adverse event during the first courses of therapy.

Prognostic impact of ATM mutations in patients with metastatic colorectal cancer

Tumors bearing homologous recombination deficiency are extremely sensitive to DNA double strand breaks induced by several chemotherapeutic agents. ATM gene, encoding a protein involved in DNA damage response, is frequently mutated in colorectal cancer (CRC), but its potential role as predictive and prognostic biomarker has not been fully investigated. We carried out a multicenter effort aimed at defining the prognostic impact of ATM mutational status in metastatic CRC (mCRC) patients. Mutational profiles were obtained by means of next-generation sequencing. Overall, 35 out of 227 samples (15%) carried an ATM mutation. At a median follow-up of 56.6 months, patients with ATM mutated tumors showed a significantly longer median overall survival (OS) versus ATM wild-type ones (64.9 vs 34.8 months; HR, 0.50; 95% CI, 0.29–0.85; P = 0.01). In the multivariable model, ATM mutations confirmed the association with longer OS (HR, 0.57; 95% CI, 0.33–0.98; P = 0.04). The prognostic impact of ATM mutations was independent from TP53 mutational status and primary tumor location. High heterogeneity score for ATM mutations, possibly reflecting the loss of wild-type allele, was associated with excellent prognosis. In conclusion, we showed that ATM mutations are independently associated with longer OS in patients with mCRC.