The impact of proton-pump inhibitors administered with tyrosine kinase inhibitors in patients with metastatic renal cell carcinoma.

Tyrosine kinase inhibitors (TKIs) are the backbone of the systemic treatment for patients with metastatic renal cell carcinoma (mRCC). TKIs such as pazopanib and cabozantinib can interact with other drugs concomitantly administered, particularly with proton-pump inhibitors (PPIs), possibly impacting the effectiveness of the anticancer treatment and patients outcome. Few data are available about this interaction. We conducted a multicenter retrospective observational data collection of patients with mRCC treated with pazopanib or cabozantinib between January 2012 and December 2020 in nine Italian centers. Univariate and multivariate analyses were performed. The aim was to describe the impact of baseline concomitant PPIs on the outcome of patients to pazopanib and cabozantinib in terms of response, progression-free survival (PFS) and overall survival (OS), toxicity, and treatment compliance. The use of PPI in our study population (301 patients) significantly influenced the effectiveness of TKIs with worse PFS (16.3 vs. 9.9 months; P < 0.001) and OS (30.6 vs. 18.4 months; P = 0.013) in patients taking PPI at TKI initiation. This detrimental effect was maintained both in the pazopanib and cabozantinib groups. The use of PPI influenced the toxicity and TKI treatment compliance with a reduction of dose or schedule modifications, and treatment interruptions in the population taking PPIs. Our study demonstrates that the use of PPIs can significantly influence the outcome and compliance of patients with mRCC to TKI treatment, suggesting the importance of a more careful selection of patients who need a gastroprotective therapy, avoiding indiscriminate use of PPIs.

Management of brain metastases from lung cancer in the era of immunotherapy: a review of the literature.

The brain is one of the most frequent sites of metastases in lung cancer patients, whose prognosis is related to the histological, biomolecular and clinical features of the disease. Over the years, the survival has improved significantly with the introduction of immune checkpoint inhibitors (ICIs), but there are limited data concerning their efficacy in patients with brain metastases. The aim of this review is to describe the biological mechanisms supporting the use of immunotherapy for brain metastases and the outcomes experienced by lung cancer patients with brain involvement enrolled in Phase III registration trials of ICIs. We also review retrospective data on ICIs alone or combined with brain radiotherapy, and indicate future directions for preclinical and clinical research.

Myositis and myasthenia during nivolumab administration for advanced lung cancer: a case report and review of the literature.

The immunotherapy significantly improved survival of non-small cell lung cancer patients, but it may cause immune-related adverse events, which are severe in less than 10% of cases. We report the case of one patient who developed myositis and myasthenia during nivolumab treatment for metastatic lung squamous carcinoma. Moreover, we reviewed literature data in order to identify similar cases in cancer patients treated with immune-checkpoints inhibitors. A 65-year-old patient, who had previously received a first-line platinum-based therapy, developed diplopia and ptosis 4 weeks after the start of nivolumab. Although antibodies associated with myositis, myasthenia gravis and paraneoplastic syndromes were absent, immune-related myositis and myasthenia were diagnosed. Corticosteroids, immunoglobulin and pyridostigmine showed poor efficacy and the patient died 7 weeks after the appearance of the first symptoms. Fifteen similar cases were found in the literature. A close collaboration between different specialists is essential to rapidly identify and treat severe immune-related adverse events.

Sequencing strategies in the new treatment landscape of prostate cancer.

Over the last 10 years, a number of new agents approved for the treatment of metastatic castration-resistant prostate cancer have led to a significant improvement in overall survival. The addition of new agents to androgen deprivation therapy has also allowed a paradigmatic change in the treatment of metastatic hormone-sensitive prostate cancer by improving overall survival in comparison with androgen deprivation therapy alone. Furthermore, recent data concerning the efficacy of three different androgen receptor-targeting agents in patients with nonmetastatic castration-resistant prostate cancer have opened up new scenarios for future patients' management. Defining the best sequencing strategies for men with prostate cancer is a currently unmet medical need, and choosing treatment is often challenging for clinicians because of the lack of direct comparisons of the available agents. The aim of this paper is to provide a comprehensive review of the literature concerning current sequencing strategies for prostate cancer patients.

Activity and safety of metronomic cyclophosphamide in the modern era of metastatic castration-resistant prostate cancer.

AIM: To evaluate activity of metronomic cyclophosphamide (mCTX) in heavily pretreated metastatic castration-resistant prostate cancer (mCRPC) patients. PATIENTS & METHODS: We retrospectively evaluated a consecutive series of 74 mCRPC patients treated with at least one new agent after docetaxel failure, who received once-daily oral mCTX treatment at a fixed dose of 50 mg. RESULTS: The treatment was well tolerated. Sixteen percent of the patients experienced a major biochemical response. Median progression-free survival was 4.0 months, and median overall survival was 8.1 months. CONCLUSIONS: In the modern context of mCRPC, mCTX may represent a valuable and inexpensive alternative to new agents, which have shown similar activity in heavily pretreated patients.

Abiraterone acetate and its use in the treatment of metastatic prostate cancer: a review.

Abiraterone acetate, which targets enzymatic complexes playing a central role in steroidogenesis, demonstrated to increase survival significantly in both chemo-naive and docetaxel pretreated, becoming one of the drugs of choice for metastatic castration-resistant prostate cancer. More recently, this agent in combination to androgen deprivation therapy demonstrated to be efficacious also in metastatic castration-sensitive prostate cancer. The present review is aimed to outline the clinical development of abiraterone acetate, the pivotal trials which led to its approval for the clinical practice, new evidence about its efficacy in metastatic castration-sensitive prostate cancer, its place in the therapeutic landscape of prostate cancer and future directions of development.

Enzalutamide after chemotherapy in advanced castration-resistant prostate cancer: the Italian Named Patient Program.

AIM: To collect efficacy and safety data of enzalutamide after docetaxel, we retrospectively evaluated the Italian Named Patient Program results. PATIENTS & METHODS: Two hundred and nine metastatic castration-resistant prostate cancer patients were enrolled. Median age was 73 years. Total 42.1% patients had pain, 14.4% had a performance status of two and 59.8% had a Gleason score ≥8. Total 31.1% had previously received ≥2 chemotherapies, 15.3 and 12% had been previously treated with abiraterone and cabazitaxel, respectively and 14.8% had received both. RESULTS:  Median progression-free survival and overall survival were 4.8 and 13.1 months, respectively. A prostate-specific antigen reduction ≥50% was observed in 49.1%. Total 32.7% abiraterone-pretreated patients achieved a biochemical response compared with 56% of abiraterone-naive patients. CONCLUSION:  Enzalutamide was safe and well tolerated. Its antitumor activity in abiraterone-pretreated patients was limited.

Concomitant Administration of VEGFR Tyrosine Kinase and Proton Pump Inhibitors May Impair Clinical Outcome of Patients With Metastatic Renal Cancer.

INTRODUCTION: The administration of proton pump inhibitors (PPIs) is a common practice to reduce gastro-esophageal adverse events associated with drug treatments but may impair absorption and exposure to oncology drugs. This study investigated the effect of concomitant administration of PPIs and pazopanib, sunitinib and cabozantinib on survival of patients with metastatic clear cell renal carcinoma (mRCC). PATIENTS AND METHODS: Total 451 patients receiving pazopanib, sunitinib and cabozantinib as first line treatment were enrolled in this retrospective study. Patients were defined as "no concomitant PPIs (PPI-)" if no PPIs were administered during TKIs, and as "concomitant PPIs (PPI+)" if the administration of PPIs was at least 75% of the time during which TKIs were given. RESULTS: Eighty patients administered pazopanib were PPI- and 86 PPI+; no difference in PFS was observed (10.7 vs. 11.9 months, P = .79). If patients were stratified as short (n = 89) and long (n = 77) responders, there was a significant difference in terms of PFS in PPI+ (n = 47) versus PPI- (n = 30) in long responders, being 24.7 versus 38 months (P = .04), respectively. In the sunitinib cohort, no significant difference of PFS in PPI+ (n = 102) versus PPI- (n = 131) was found, being 11.3 versus 18.1 months, respectively (P=0.15). In the cabozantinib cohort, there was a statistically significant difference in PFS of PPI+ versus PPI- (6 months vs. not reached, P = .04). No correlation with adverse events was found. CONCLUSIONS: This study demonstrates an association between PPIs and impaired PFS in mRCC patients given pazopanib and cabozantinib and recommends caution on their concomitant use.

Impact of KRAS Mutations on Clinical Outcomes of Patients with Advanced Non-Squamous Non-Small Cell Lung Cancer Receiving Anti-PD-1/PD-L1 Therapy.

BACKGROUND: KRAS is the most frequently mutated gene in non-small cell lung cancer (NSCLC), however conflicting data are available on its role as a biomarker. OBJECTIVE: The aim of our work was to investigate the impact of KRAS mutations on response and survival outcomes in advanced non-squamous NSCLC patients treated with immune checkpoint inhibitors alone or in combination with chemotherapy. PATIENTS AND METHODS: We retrospectively identified 119 patients, most of whom (58%) were KRAS wild type. For each patient we evaluated overall survival (OS), progression-free survival (PFS), and disease control rate (DCR). An exploratory analysis was performed among KRAS mutated patients to investigate the impact of specific KRAS mutations on response and survival outcomes. RESULTS: After a median follow-up of 10.3 months, the median OS was 14.9 months (95% confidence interval [CI] 7.6-22.7) in wild-type KRAS patients versus 14.7 months (95% CI 8.0-19.5) in mutated KRAS patients (p = 0.529). No differences were detected between the two groups in terms of PFS and DCR. Patients with a KRAS G12C mutation reported survival and response outcomes that were not statistically different from those of patients with other KRAS mutations. CONCLUSION: Our data confirmed that KRAS mutational status is not associated with survival and response outcomes in advanced non-squamous NSCLC patients treated with immunotherapy alone or combined with chemotherapy.

The role of mean corpuscular volume and red cell distribution width in patients with metastatic renal cell carcinoma treated with tyrosine kinase inhibitors: the MARECAP retrospective study.

Background: Tyrosine-kinase inhibitors (TKIs) and immunotherapy represent the backbone treatment for metastatic renal cell carcinoma (mRCC) patients. The aim of the present study was to describe mean corpuscular volume (MCV) and red cell distribution width (RDW) in mRCC patients treated with pazopanib or cabozantinib, and to explore their potential impact on oncological outcomes. Materials and methods: We conducted a multicenter retrospective observational study in mRCC patients treated with pazopanib or cabozantinib between January 2012 and December 2020 in nine Italian centers. Descriptive statistics, univariate, and multivariate analyses were performed. Objectives: The primary endpoints were the incidence and trend over time of anemia, macrocytosis (elevated MCV), and anisocytosis (elevated RDW). The secondary endpoints were the correlations of MCV and RDW with objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). Results: A total of 301 patients were enrolled; mean Hb value was 12.5 g/dl, a mean increase of 1 g/dl was observed at day 15 and maintained at 3 months. Most patients had baseline macrocytosis (MCV levels > 87 fl), with a significant mean increase after 3 months of treatment. At univariate analysis patients with macrocytosis had better ORR, longer PFS, and OS. About one third of patients had baseline anisocytosis (RDW > 16%), with a significant mean increase after 3 months of treatment. At univariate analysis, patients with RDW values ⩽ 16% had higher ORR, longer PFS, and OS. At multivariate analysis, baseline macrocytosis was significantly associated with better PFS in patients treated with pazopanib and baseline anisocytosis with shorter OS in all patients. Conclusions: mRCC patients treated with pazopanib or cabozantinib may have baseline macrocytosis and anisocytosis. A significant increase of Hb, MCV, and RDW after TKIs start was observed. Baseline macrocytosis is positively correlated with PFS in patients treated with pazopanib and baseline anisocytosis affects survival of patients treated with TKIs.

Integrating Red Blood Cell Features and Hemoglobin Levels in Metastatic Renal Cell Carcinoma Patients Treated with Pazopanib or Cabozantinib: An Easily Exploitable Prognostic Score.

BACKGROUND: The advent of immune checkpoint inhibitors (ICIs) has revolutionized the metastatic renal cell carcinoma (mRCC) therapeutic landscape. Nevertheless, tyrosine-kinase inhibitors (TKIs) targeting the vascular endothelial growth factor (VEGF) axis still play a key role. The aim of the present study was to explore the prognostic performance of an integrated blood score, based on hemoglobin (Hb) concentration, mean corpuscular volume (MCV), and red cell distribution width (RDW), in mRCC patients treated with anti-VEGF TKIs. The primary endpoint was to correlate Hb, MCV, and RDW with progression-free survival (PFS) and overall survival (OS). MATERIALS AND METHODS: Our multicenter retrospective observational study involved mRCC patients treated with pazopanib or cabozantinib from January 2012 to December 2020 in nine Italian centers. Clinical records and laboratory data, including Hb levels, MCV, and RDW, were collected at baseline. Descriptive statistics and univariate and multivariate analyses were performed. RESULTS: We enrolled 301 mRCC patients of which 179 (59%) underwent pazopanib, and 122 (41%) cabozantinib. We considered baseline Hb ≥12 g/dL, MCV >87 fL, and RDW ≤16% as good prognostic factors; hence, developing a multiparametric score capable of delineating 4 different categories. The number of good prognostic factors was associated with significantly longer PFS and OS (p < 0.001 for both). Therefore, we developed a red blood cell-based score by stratifying cases into two groups (2-3 versus 0-1, good factors). The impact on PFS and OS was even more striking (median PFS (mPFS): 16.3 vs 7.9 months; median OS (mOS): 33.7 vs 14.1 months)), regardless of the TKI agent. When challenged with univariate and multivariate analysis, the blood score maintained its high prognostic significance in terms of OS (multivariate analysis HR for OS: 0.53, 95% CI 0.39-0.75; p < 0.001, respectively), while the impact on PFS resulted in borderline significance. CONCLUSIONS: Our analyses demonstrate the prognostic role of a multiparametric score based on easily exploitable blood parameters, such as Hb concentration, MCV, and RDW. The red blood cell-based score may underlie the upregulation of the HIF-1α pathway and VEGF axis, thereby identifying a selected population who is likely to benefit from TKI therapy.

Tailoring treatment with cabozantinib or pazopanib in patients with metastatic renal cell carcinoma: does it affect outcome?

BACKGROUND: Metastatic renal cell carcinoma (mRCC) treatment is still largely based on TKI use. Treatment adjustment due to toxicities is often needed. The aim of the present study was to determine the impact of treatment modifications on the outcome of mRCC patients treated with cabozantinib or pazopanib. RESEARCH DESIGN AND METHODS: This retrospective multicenter study enrolled consecutive patients receiving cabozantinib or pazopanib between January 2012 and December 2020. We evaluated the correlation of TKI treatment modifications with grade 3-4 toxicities and progression-free (PFS) and overall survival (OS). We also performed a landmark analysis excluding patients who did not undergo at least 5 months of therapy. RESULTS: Among 301 patients, 179 (59%) were treated with pazopanib, 122 (41%) with cabozantinib. Treatment modifications were related to grade 3-4 toxicities (p < 0.0001). We observed a statistically significant longer PFS and OS in patients who underwent dose reductions (p < 0.0001 for both PFS and OS), temporary interruption (p < 0.0001 for both PFS and OS) and schedule modifications (p = 0.007 for PFS and p = 0.012 for OS) at univariate analysis. These results were confirmed at multivariable and landmark analyses. CONCLUSIONS: Tailoring treatment with pazopanib and cabozantinib was associated with better PFS/OS.

Rheumatic immune-and nonimmune-related adverse events in phase 3 clinical trials assessing PD-(L)1 checkpoint inhibitors for lung cancer: A systematic review and meta-analysis.

OBJECTIVES: We aimed to analyze rheumatic immune-related (ir) and nonimmune-related adverse events (AEs) due to immune-checkpoint inhibitors (ICIs) targeting programmed cell death-1 or its ligand PD-(L)1 in lung cancer patients from the available literature. METHODS: We performed a systematic review and meta-analysis of phase III randomized clinical trials (RCTs) assessing PD-(L)1-ICIs in lung cancer patients, from inception until January 12th, 2021. We extracted data of each trial to estimate odds ratio (OR) for rheumatic ir or non-irAE as classified in RCTs safety data. Sensitivity analyses (by ICI, treatment group and histology) were performed. RESULTS: Eighteen RCTs met the inclusion criteria (n=12172 subjects). The OR [95%IC] for rheumatic irAE in ICIs versus controls (either placebo or chemotherapy) was 2.20 [0.85,5.72]. Among rheumatic non-irAEs, both overall and severe (grade≥3) back pain were significantly more frequent in ICIs versus controls, 2.01 [1.09;3.73] and 2.90 [1.18;7.08], respectively. The overall frequency of arthralgia was similar between ICIs and controls; by sensitivity analysis RCTs assessing ICIs in combination with chemotherapy showed a significant association with arthralgia (1.55 [1.15;2.10]). Similarly, the frequency of myalgia was significantly lower in RCTs assessing ICIs alone versus chemotherapy (OR 0.32 [0.24;0.42]). Muscular pain was not significantly increased with ICI. CONCLUSION: Rheumatic irAEs are not increased in RCTs assessing PD-(L)1 inhibitors, not reflecting the real-life incidence, therefore likely underreported or misclassified. Back pain is significantly associated with them regardless its severity, while arthralgia only when ICIs are added on conventional chemotherapy.

To treat or not to treat: is it acceptable to avoid active therapies in advanced prostate cancer today?

Introduction: Recently, there has been a paradigm shift in the treatment of advanced prostate cancer (PCa) because the approval of a number of new agents has significantly improved overall survival. However, as PCa is a heterogeneous disease that may be more or less aggressive and patients may be more or less responsive to treatment, it is often debated whether or not it is acceptable to avoid active therapies.Areas covered: This review discusses different settings of advanced PCa.Expert opinion: In metastatic castration-resistant PCa, it is unethical not to use active treatments but the use of both androgen receptor targeting agents (ARTA) in sequence should be avoided in most patients and the use of the available agents for fourth-line treatment or beyond should only be considered for highly selected patients. In metastatic hormone-sensitive PCa, patients with de novo disease should receive one additional agent in combination with androgen deprivation therapy (ADT), whereas patients in relapse should be managed with ADT alone. In non-metastatic castration-resistant prostate cancer (PCa), all patients with a PSA doubling time of ≤6 months should receive one ARTA, whereas the others might wait until there is an acceleration in the kinetics of their PSA levels.

Severe acute respiratory syndrome coronavirus 2 infection in patients with prostate cancer: A critical review.

Real-world data suggest a possible interplay between androgen deprivation therapy (ADT) and susceptibility to and the severity of SARS-CoV-2 infection. As ADT is the backbone of prostate cancer treatment, various authors have evaluated different patient cohorts but the evidence provided is conflicting. The aim of this review is to assess the available publications concerning the role of ADT in preventing or reducing the severity of SARS-CoV-2 infection. After a literature search we identified four full papers, five letters, and four meeting abstracts, but these used different search methods and the quality of the evidence varied. They frequently had different endpoints, did not report the status of the prostate cancer patients and evaluated heterogeneous populations. The available data do not support the view that ADT protects against SARS-CoV-2 infection. Larger and more precise studies are warranted, considering variables that affect infection outcomes as these significantly influence the reliability of the findings.

Meta-analysis of immune-related adverse events in phase 3 clinical trials assessing immune checkpoint inhibitors for lung cancer.

INTRODUCTION: The introduction in clinical practice of the immune checkpoint inhibitors (ICIs) radically changed the treatment algorithm of lung cancers. To characterize the toxicity of ICIs (atezolizumab, durvalumab, nivolumab, pembrolizumab) is important for personalizing treatment. PATIENTS AND METHODS: We performed a systematic review and meta-analysis of phase III randomized controlled trials assessing ICIs, from inception until April 23rd, 2020. We extracted the data from the ICI arm of each trial for indirect comparisons to estimate relative risk for immune-related adverse events (irAEs), severe (grade ≥3) irAEs, drug discontinuation due to irAEs or toxic death. RESULTS: Sixteen trials included a total of 6226 subjects randomized to the experimental immunotherapy arm. Immunotherapy was administered in monotherapy (8 trials), in combination with chemotherapy (6 trials) or other ICI (2 trials). Any grade irAEs and severe irAEs for ICI were 37.1% and 18.5%, respectively. Discontinuations due to any grade irAEs and severe irAEs were 13.8% and 9.2%, respectively; toxic deaths were 2.9% in the immunotherapy arm. Pooled data on any, severe and organ-specific irAEs showed that immunotherapy has a significantly lower risk of irAEs compared to immuno-chemotherapy, especially when analysis was restricted to monoimmunotherapy, like drug discontinuation and toxic death (all p < 0.05). Detailed comparisons between different ICIs provided treatment-related risk profiles for organ-specific irAEs. CONCLUSIONS: Our findings contribute to clarifying frequency and features of immune-related toxicities between different ICIs in lung cancer patients, including any grade irAEs, severe irAEs, drug discontinuation and toxic deaths, and may be useful to inform the selection of treatment.

Pretreatment lung immune prognostic index as a biomarker in advanced non-small-cell lung cancer patients receiving first line pembrolizumab.

Background: To investigate the role of pretreatment lung immune prognostic index (LIPI) as biomarker in PD-L1 ≥50% non-small-cell lung cancer patients receiving pembrolizumab. Patients & methods: We retrospectively identified 117 patients, divided into three prognostic groups according to LIPI score. For each patient, we evaluated 1-year overall survival (OS) and progression-free survival rate. C-statistic and survival receiver operating characteristic curves were used to study discrimination of LIPI. Results: After a median follow-up of 11.7 months, 1-year OS rate was 60.1%, 35.3% and 28.6%, while 1-year progression-free survival rate was 39.1%, 20.6% and 14.3% in good, intermediate and poor LIPI groups, respectively (p < 0.001). The c-statistic and area under the curve of LIPI were 0.63 and 0.662 for OS and 1-year OS, respectively. Conclusions: Higher LIPI score is related to worse survival in advanced non-small-cell lung cancer patients treated with first-line pembrolizumab. However, based on c-statistic and area under the curve, LIPI does not represent a good prognostic survival model.

Lay abstract In recent years, immunotherapy has become a milestone in the treatment of non-small-cell lung cancer, but clinicians need clinical and/or laboratory factors able to predict the benefit of immunotherapy. Therefore, we investigated the role of pretreatment lung immune prognostic index (LIPI) as biomarker in advanced non-small-cell lung cancer patients with high PD-L1 expression levels and receiving pembrolizumab as first line. We retrospectively identified 117 patients divided into three prognostic groups (good, intermediate and poor) according to LIPI score. We found that patients belonging to good prognostic group (LIPI score 0) lived longer and responded better than those of intermediate and poor prognostic groups (LIPI score 1 or 2), confirming the correlation between LIPI score and survival and response outcomes.

Docetaxel and prednisone with or without enzalutamide as first-line treatment in patients with metastatic castration-resistant prostate cancer: CHEIRON, a randomised phase II trial.

BACKGROUND: Pre-clinical data suggest that docetaxel and enzalutamide interfere with androgen receptor translocation and signalling. The aim of this study is to assess the efficacy of their concurrent administration in the first-line treatment for metastatic castration-resistant prostate cancer (mCRPC). METHODS: In this open-label, randomised, phase II trial, previously untreated mCRPC patients were randomised 1:1 to receive eight 21-d courses of docetaxel 75 mg/m2, oral prednisone 5 mg twice daily and oral enzalutamide 160 mg/d (arm DE), or the same treatment without enzalutamide (arm D). The primary end-point was the percentage of patients without investigator-assessed disease progression 6 months after the first docetaxel administration. RESULTS: The 246 eligible patients were randomly assigned to receive docetaxel, prednisone and enzalutamide (n = 120) or docetaxel and prednisone (n = 126). The 6-month progression rate was 12.5% (95% confidence interval [CI] 8.1-20.6) in arm DE and 27.8% (95% CI 22.8-39.4) in arm D (chi-squared test 10.01; P = 0.002). The most frequent grade III-IV adverse events were fatigue (12.5% in arm DE versus 5.6% in arm D), febrile neutropenia (9.3% versus 4.0%) and neutropenia (7.6% versus 5.6%). CONCLUSIONS: The combination of enzalutamide and docetaxel appears to be more clinically beneficial than docetaxel alone in previously untreated mCRPC patients, although serious adverse events were more frequent. Our findings suggest that first-line treatment with this combination could lead to an additional clinical benefit when prompt and prolonged disease control is simultaneously required. Clearly, these results should be considered cautiously because of the study's phase II design and the absence of an overall survival benefit. TRIAL REGISTRATION NUMBERS: EudraCT 2014-000175-43 - NCT02453009.

Role of circulating tumor DNA in the detection of sensitizing and resistance to epidermal growth factor receptor mutations in metastatic lung adenocarcinoma.

PURPOSE: The EGFR (Epidermal Growth Factor Receptor) mutations may predict sensitivity and resistance to EGFR-TKIs (Tyrosine Kinases Inhibitors) in metastatic lung adenocarcinoma. The detection of these mutations is usually performed on tumor tissue samples. However, when a biopsy is not feasible or the amount of tissue is limited, circulating tumor DNA (ctDNA) may represent an alternative source for genotyping the tumor. METHODS: In the first phase of the study, the liquid biopsy was performed in newly diagnosed metastatic lung adenocarcinoma patients with and without EGFR mutations to evaluate the concordance between EGFR mutational analysis on ctDNA by real time PCR and on tissue. In the second phase it was performed in EGFR positive patients progressing after first or second generation TKIs in order to detect the T790M mutation. RESULTS: In the first phase, a 100% concordance between EGFR on ctDNA and tissue was revealed, leading to validation of the test. In the second phase, 44.8% of patients showed T790M positive result at liquid biopsy. Considering the re-biopsies performed in 31% of the cases, the overall positivity rate of T790M was 58.6%. Sensitivity and specificity were 76% and 75%, respectively. The median time to development of T790M mutation from the start of first line EGFR TKI was 244 days. CONCLUSIONS: Our experience confirms that liquid biopsy is a valid method to detect sensitizing and resistant EGFR mutations in patients with metastatic lung adenocarcinoma. Nevertheless, in the presence of negative ctDNA analysis, a rebiopsy should be performed whenever possible to confirm this result.