Therapeutic approaches for T790M mutation positive non-small-cell lung cancer

Introduction: Epidermal growth factor receptor (EGFR) mutation positive non-small cell lung cancer (NSCLC) is a subset of lung cancer with demonstrated response to targeted therapies. However, resistance to the first targeted approach usually occurs within the first year, and it is associated in 50–60% of cases to the T790M resistance mutation.

Areas covered: The review provides an overview on the significance of the presence of the T790M mutation, its detection, treatment options and subsequent mechanisms of resistance.

Expert commentary: Osimertinib is the current treatment option for T790M mutation positive NSCLC after progression to first or second-generation EGFR TKIs, with activity also on brain metastasis. However, the scenario is in continuous evolution and results from clinical trials are awaited in first-line setting and in combination strategies.     

NGS analysis on tumor tissue and cfDNA for genotype-directed therapy in metastatic NSCLC patients. Between hope and hype?

Introduction: The advent of genomic based precision medicine led to the implementation of biomarker testing in metastatic non-small cell lung cancer (NSCLC) patients. Next generation sequencing (NGS) has been recently implemented to routine diagnostic requirements in lung oncology.

Areas covered: Two cases of patients with metastatic NSCLC for whom NGS analysis performed on both tumor and liquid biopsy has not improved the clinical course of their disease are reported. These cases illustrate the difficulty of the so-called ‘personalized or precision’ medicine in clinical routine practice for metastatic NSCLC.

Expert commentary: Discovery and detection of critical cancer-gene alterations better indicates targeted therapies that must be administered to improve the care of NSCLC patients in the personalized medicine era. There has been much interest in the literature and the scientific community for NGS tailored therapies approach for patients. However, there may be a gap between this theoretical stratified medicine and clinical practice. The advantages and drawbacks of NGS on tumor tissue and cell-free DNA for metastatic NSCLC are discussed.     

Small cell lung cancer transformation from EGFR-mutated lung adenocarcinoma: A case report and literatures review

Epithelial growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) have markedly improved the response of non-small cell lung cancer (NSCLC) with EGFR-mutant patients. However, these patients inevitably come cross acquired resistance to EGFR-TKIs. The transformation of lung adenocarcinoma to small cell lung cancer (SCLC) following treatment with EGFR-TKIs is rare, which leads to resistance to EGFR-TKIs.

The present case concerns a case of a 38-year-old man presenting with cough and dyspnea. Radical resection was performed and confirmed an EGFR exon 21 L858R lung adenocarcinoma. However, the patient suffered pleural metastasis after successful treatment with surgery and adjuvant treatment. So, erlotinib was administered with 18 months. Because of enlarged pleural nodule, repeat biopsy identified an SCLC and chemotherapy was started. However, despite the brief success of chemotherapy, our patient suffered brain metastasis.

Our case emaphsizes both the profile of transformation from NSCLC to SCLC and the importance of repeat biopsy dealing with drug resistance. We also summarize the clinical characteristics, mechanisms, predictors of SCLC transformation, treatment after transformation and other types of transformation to SCLC.     

Liver-directed therapy in metastatic colorectal cancer

Introduction: Colorectal cancer is a significant global health issue with over 1 million cases diagnosed annually throughout the world. 15% of patients diagnosed with colorectal cancer will have liver metastases and 60% will develop liver metastases if they have metastatic disease. Oligometastatic colorectal cancer confined to the liver represents an intermediate state in the evolution of metastatic capacity that opens the opportunity for local interventions.

Areas covered: The literature supports long-term survival if patients undergo liver resection of colorectal metastases. This article reviews the liver-directed therapeutic strategies available for the management of metastatic liver disease including hepatic arterial infusion therapy, radiofrequency ablation, radiation therapy and transarterial chemoembolization.

Expert commentary: Great advances have been made with the use of liver directed therapies. In the USA using hepatic arterial infusions with FUDR and Decadron along with systemic therapy, 5 year survivals after liver resection have improved. In Europe with the use of HAI of Oxaliplatin, more patients have been able to get to resection and have obtained higher survival rates, even in second line therapy. New advances in ablative therapy have improved results to get all disease treated at resection for the treatment of reccurrence     

Advances in the use of surgery and multimodality treatment for N2 non-small cell lung cancer

Introduction: Stage IIIA-N2 non-small cell lung cancer (NSCLC) represents a heterogeneous group of bronchogenic carcinomas with locoregional involvement. Different categories of N2 disease exist, ranging from unexpectedly encountered N2 involvement after detailed preoperative staging or ‘surprise’ N2, to potentially resectable disease treated within a combined modality setting, and finally, bulky N2 involvement treated by chemoradiation.

Areas covered: Large randomised controlled trials and meta-analyses on stage IIIA-N2 NSCLC have been published but their implications for treatment remain a matter of debate. No definite recommendations can be provided as diagnostic and therapeutic algorithms vary according to local, national or international guidelines.

Expert commentary: From the literature, it is clear that patients with stage IIIA-N2 NSCLC should be treated by combined modality therapy including chemotherapy, radiotherapy and surgery. The relative contribution of each modality has not been firmly established. For patients undergoing induction therapy, adequate restaging is important as only down-staged patients will clearly benefit from surgical resection. Each patient should be discussed within a multidisciplinary team to determine the best diagnostic and therapeutic approach according to the specific local expertise. In the near future, it might be expected that targeted therapies and immunotherapy will be incorporated as possible therapeutic options.     

Capture-based ultra-deep sequencing in plasma ctDNA reveals the resistance mechanism of ALK inhibitors in a patient with advanced ALK-positive NSCLC

Background: Anaplastic lymphoma kinase (ALK) is a validated molecular target in non–small-cell lung cancer (NSCLC). However, the clinical benefits of ALK inhibitors are almost universally limited by the emergence of drug resistance.

Methods: We monitored the plasma circulating tumor DNA (ctDNA) using captured-based ultra-deep sequencing analysis of one patient with metastatic ALK-positive NSCLC who had received therapies including first-, second- and third-generation ALK inhibitors. Functional in vitro studies were further undertaken to elucidate the mechanism of resistance.

Results: ALK T1151Sins mutation was detected when the patient developed resistance to ceritinib, and undetectable when she responded to lorlatinib. MET amplification was present when the tumor developed resistance to lorlatinib, and reduced when the patient received combination therapy of lorlatinib with crizotinib, which corresponded to clinical radiologic responses. In addition, further functional in vitro studies demonstrated that ALK harboring the T1151Sins mutation, while conferring resistance to ceritinib, was inhibited by lorlatinib.

Conclusions: Clinical evidence and in vitro validation revealed the clinical usefulness of captured-base ultra-deep sequencing on longitudinal plasma ctDNA in revealing the underlying resistance mechanism and guiding the precise administration of ALK inhibitors in patients with advanced ALK-positive NSCLC.     

Combined therapy with epidermal growth factor receptor tyrosine kinase inhibitors for non–small cell lung cancer

Introduction: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have a pronounced clinical benefit for patients with advanced non–small cell lung cancer (NSCLC) positive for EGFR activating mutations. Such individuals inevitably develop resistance to these drugs, however, new treatment strategies to overcome such resistance are being actively pursued. The clinical benefit of EGFR-TKIs for patients with locally advanced NSCLC remains to be clarified.

Areas covered: This review summarizes the recent progress in combination treatment with EGFR-TKIs and either chemotherapy or radiotherapy for patients with NSCLC positive for EGFR activating mutations.

Expert commentary: Combination therapy with EGFR-TKIs and various other treatment options are under investigation in clinical studies. Although early studies failed to show a clinical benefit for such combination therapy because of a lack of patient selection, clinical studies with patient selection based on EGFR mutation status have shown promising results. Such combination therapy might eventually replace the current standard treatment for patients with NSCLC positive for EGFR activating mutations.     

Current status of research and treatment for non-small cell lung cancer in never-smoking females

Lung cancer is the leading cause of cancer-related deaths worldwide with over 1 million deaths each year. The overall prognosis of lung cancer patients remains unsatisfactory, with a 5-year overall survival rate of less than 15%. Although most lung cancers are a result of smoking, approximately 25% of lung cancer cases worldwide are not attributable to tobacco use. Notably, more than half of the lung cancer cases in women occur in non-smokers. Among non-small-cell lung cancer (NSCLC) cases, cigarette-smokers have a greater association with squamous cell carcinoma than adenocarcinoma, which is more common in non-smokers. These findings imply that specific molecular and pathological features may associate with lung adenocarcinoma arising in non-smoker female patients.

Over the past decade, whole genome sequencing and other ‘-omics’ technologies led to the discovery of pathogenic mutations that drive tumor cell formation. These technological developments may enable tailored patient treatments throughout the course of their disease, potentially leading to improved patient outcomes. Some clinical and laboratory studies have shown success outcomes using epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitors (TKI) in patients with EGFR mutations and ALK rearrangements, respectively. In fact, these 2 mutations are predominantly present in female non-smokers with adenocarcinoma. Immunotherapy has also recently emerged as a major therapeutic modality in NSCLC.

In this review, we summarize the current understanding of NSCLC biology and new therapeutic molecular targets, focusing on the pathogenesis of non-smoker female NSCLC patients.     

Liver metastases resection for gastric and esophageal tumors: is there enough evidence to go down this path?

Introduction: Surgical resection of liver metastases from colorectal and neuroendocrine tumours has become a standard of care for resectable patients with isolated hepatic disease and good performance status, leading to extended survival in a carefully selected subgroup of these patients. However, the role of hepatic surgery in gastric and oesophageal liver metastases is controversial and not clearly defined.

Areas covered:a systematic electronic literature search was performed to select the most representative evidence regarding hepatectomies in liver metastases from these two tumours. PubMed, Medline, Embase Ovid and Google Scholar databases were scanned for articles written in English and published in peer-reviewed journals between 1994 and May 2016.

Expert commentary: Given the shortage of randomised studies and the limited number of patients in many of the studies discussed here, the evidence base for the use of hepatectomies in these settings is not strong. Thus, while the data for resections of gastric liver metastases may in particular seem encouraging, the results should be interpreted with caution.     

Undetected lymph node metastases in presumed early stage NSCLC SABR patients

Introduction: Stereotactic body radiation therapy (SBRT, also called stereotactic ablative body radiation SABR) is the treatment of choice for many patients with early-stage non-small cell lung cancer (NSCLC), including those who are unfit for surgery or refuse surgery.

Areas covered: In an effort to develop optimal staging for the evaluation of SBRT candidates, we review the performance of available lymph node staging methods, as well as risk factors for lymph node involvement. Pubmed was searched to identify relevant literature. Current staging methods for NSCLC, including Positron Emission Tomography/Computed Tomography(PET/CT) and endobronchial ultra sound (EBUS), have limited sensitivities.

Expert commentary: There are several factors, including primary tumor location, tumor size, and histology that are possibly associated with the sensitivity of PET/CT to detect mediastinal lymph node metastasis. Small lymph node metastases typically remain undetected by PET/CT. Therefore invasive nodal staging procedures are indicated for most presumed early-stage NSCLC patients, but these also have limited sensitivity. Occult lymph node metastasis is associated with adverse outcome in NSCLC. Moreover, there is overwhelming evidence that certain patients who have lymph node metastases detected at the time of surgery derive an overall survival benefit from adjuvant therapies. It remains to be determined if improved detection of lymph node metastases in SABR candidates can indeed improve prognosis.     

The liquid biopsy: a tool for a combined diagnostic and theranostic approach for care of a patient with late-stage lung carcinoma presenting with bilateral ocular metastases

Introduction: Liquid biopsies (LB) are used routinely in clinical practice in two situations for late stage non-small-cell lung cancer (NSCLC) patients, (i) at the initial diagnosis when looking for activating mutations in EGFR in the absence of analyzable tissue DNA and, (ii) during tumor progression on a tyrosine kinase inhibitor treatment to look for the resistance mutation T790M in EGFR. LB is not presently recommended in daily practice for the diagnosis of NSCLC.

Areas covered: We report the diagnosis of a NSCLC in a patient with bilateral ocular metastases after detection of a deletion in exon 19 of EGFR when using plasma DNA. Without histological analysis, the origin of the primary ocular metastasis was uncertain. In this context, a LB showing an activating mutation in EGFR and circulating tumor cells positive for TTF1 led to the diagnosis of NSCLC and targeted therapy.

Expert commentary: When no tumor tissue sample is available a LB can be used to diagnose for metastatic NSCLC, when a mutation in EGFR is identified. While a tissue biopsy is the gold standard approach for the diagnosis of a NSCLC and for identification of activating mutations, LB can exceptionally provide both a diagnosis of the primitive tumor and indicate appropriate therapy based on a molecular analysis.     

Cabozantinib for the treatment of kidney cancer

Introduction: Cabozantinib is a small molecule tyrosine kinase inhibitor that initially showed activity in medullary thyroid cancer and was recently approved by the Food and Drug Administration for the treatment of metastatic renal cell carcinoma after progression on first line therapy.

Areas covered: In the METEOR trial, cabozantinib demonstrated significantly improved efficacy in all three endpoints; response rates, progression free survival and overall survival in a randomized trial with everolimus as an active comparator. Cabozantinib also showed activity in the front line setting in RCC within the CABOSUN trial. The study randomized untreated metastatic RCC patients to either cabozantinib or sunitinib and the former showed improved progression free survival which was the primary endpoint. The future holds promise for indications in other malignancies, given the preliminary efficacy and unique mechanism of action of cabozantinib.

In this review we address the mechanism of action, pharmacodynamics and pharmacokinetics of cabozantinib, and also review the development pathway of this agent in the treatment of advanced renal cell carcinoma. The potential benefit in specific patient populations, such as poor risk patients and bone metastases subgroups is also discussed.

Expert commentary: The clinical applications of cabozantinib will be addressed within the context of the current competitive therapeutic landscape of RCC.     

Therapeutic approaches for refractory germ cell cancer

Introduction: Most germ cell cancer patients with metastatic disease are cured by cisplatin-based combination chemotherapy. 30% of metastatic patients will develop relapse or progress despite adequate first-line treatment and will require salvage therapy, with about 10% of metastasized patients ultimately developing platinum-resistant and fatal disease.

Areas covered: Based on a comprehensive literature search of MEDLINE, EMBASE and conference proceedings of ESMO, ASCO and EAU meetings, this review provides an overview on current and potential future treatment options for platinum-refractory germ cell cancer patients including cytostatics and molecularly targeted therapies.

Expert commentary: Treatment of platinum-refractory disease remains challenging and long-term survival is rarely achieved despite multimodal treatment approaches. Targeted treatment approaches do not yet play a role in the treatment of platinum-refractory disease due to lacking efficacy in small, unselected clinical trials. Inclusion of patients into clinical trials is strongly recommended.     

Anti–PD-1/PD-L1 antibodies in non-small cell lung cancer: the era of immunotherapy

Introduction: Advanced non-small cell lung cancer (NSCLC) has been conventionally treated with cytotoxic chemotherapy with short-lived responses and significant toxicities. Monoclonal antibodies to programmed death-1 receptor (PD-1) and programmed death ligand 1 (PD-L1) have shown tremendous promise in the treatment of advanced NSCLC in various clinical trials.

Areas covered: In this article, we will review the outcomes of various trials of anti-PD-1/anti-PD-L1 antibodies in the treatment of NSCLC. We will also discuss their mechanism of action and toxicities.

Expert commentary: Anti-PD-1/PD-L1 antibodies offer several advantages including significant antitumor activity, induction of long lasting responses, and favorable safety profile. Several trials are now being conducted to evaluate their efficacy as first line agents as well as in combination with other agents. More research is also needed to identify other biomarkers, in addition to PD-L1 expression, that could more reliably predict response to these drugs, and aid in better patient selection.     

Myoglobin does not predict local toxicity in isolated limb perfusion

Introduction: Isolated limb perfusion (ILP) is a treatment option for patients with in-transit metastases of malignant melanoma in the extremities, as well as locally advanced sarcoma. ILP allows for a delivery of high-dose chemotherapy to an isolated extremity with minimal systemic toxicity. However, local toxicity like oedema, blistering, nerve damage and compartment syndrome can occur. Myoglobin measurements have been used as a screening method to predict the most severe cases of local toxicity. The aim was to investigate if myoglobin is a predictive factor for local toxicity after ILP in patients with melanoma in-transit metastases.

Methods: One hundred and ninety-three patients were treated for the first time with ILP for in-transit metastases between 2001 and 2015. Myoglobin was measured once the first hours after the perfusion (POD0), and for the first five post-operative days (POD1-5). Local toxicity was graded according to Wieberdink, and grouped in mild (I and II), moderate (III), and severe (IV and V). Wieberdink-groups were compared with myoglobin measurements, and myoglobin measurements were compared between gender, perfusion time, perfusion temperature and cannulated vessels.

Results: There is no statistically significant difference in myoglobin serum levels during the first five days post perfusion between patients suffering from mild, moderate or severe local toxicity. There is no difference between toxicity groups when it comes to distribution of sex, tumour size, or tumour numbers.

Conclusion: Levels of myoglobin do not predict local toxicity for patients with melanoma in-transit metastases treated with ILP when measured during the first five post-operative days.     

Central nervous system involvement in ALK-rearranged NSCLC: promising strategies to overcome crizotinib resistance

Introduction: ALK rearranged Non Small Cell Lung Cancers (NSCLCs) represent a distinct subgroup of patients with peculiar clinic-pathological features. These patients exhibit dramatic responses when treated with the ALK tyrosine kinase inhibitor Crizotinib, albeit Central Nervous System (CNS) activity is much less impressive than that observed against extracranial lesions. CNS involvement has become increasingly observed in these patients, given their prolonged survival. Several novel generation ALK inhibitors have been developing to increase CNS penetration and to provide more complete ALK inhibition..

Areas covered: The CNS activity of Crizotinib and novel generation ALK inhibitors will be summarized in this review, evaluating the strengths and weaknesses of the therapeutic strategies developed to date in this specific subgroup of NSCLCs with a look towards the future.

Expert commentary: In the next few years, the results of ongoing comparative head-to-head trials will provide the definitive conclusions on the optimal treatment sequence in ALK-rearranged NSCLCs. Moreover, ongoing clinical trials with novel-generation ALK inhibitors will produce more evidences on the best approach in the growing number of ALK-positive NSCLCs with CNS involvement.     

Role of chemotherapy and targeted therapy in early-stage non-small cell lung cancer

Introduction: Adjuvant platinum based chemotherapy is accepted as standard of care in stage II and III non-small cell lung cancer (NSCLC) patients and is often considered in patients with stage IB disease who have tumors ≥ 4 cm. The survival advantage is modest with approximately 5% at 5 years.

Areas covered: This review article presents relevant data regarding chemotherapy use in the perioperative setting for early stage NSCLC. A literature search was performed utilizing PubMed as well as clinical trial.gov. Randomized phase III studies in this setting including adjuvant and neoadjuvant use of chemotherapy as well as ongoing trials on targeted therapy and immunotherapy are also discussed.

Expert commentary: With increasing utilization of screening computed tomography scans, it is possible that the percentage of early stage NSCLC patients will increase in the coming years. Benefits of adjuvant chemotherapy in early stage NSCLC patients remain modest. There is a need to better define patients most likely to derive survival benefit from adjuvant therapy and spare patients who do not need adjuvant chemotherapy due to the toxicity of such therapy. Trials for adjuvant targeted therapy, including adjuvant EGFR-TKI trials and trials of immunotherapy drugs are ongoing and will define the role of these agents as adjuvant therapy.     

The safety and efficacy of nivolumab in advanced (metastatic) non-small cell lung cancer

Introduction: Advanced non-small cell lung cancer (NSCLC) is a challenging oncological problem. Following standard initial therapy, disease progression will typically develop. Patients with relapsed or refractory disease are left with limited treatment options. The advent of nivolumab, a monoclonal antibody against Program Death-1 (PD-1), has substantially changed the outlook for such patients.

Area covered: Nivolumab is the first checkpoint immunotherapeutic agent to gain regulatory approval for NSCLC. By enabling host immune-mediated cytotoxic activity against tumor cells, nivolumab induces a partial or complete tumor response in 15–20% of patients, regardless of number of previous lines of anti-cancer therapy. Nivolumab-related adverse effects are generally milder and less frequent than those observed with conventional cytotoxic chemotherapy. Although immune-related adverse events such as fatal pneumonitis have been reported with nivolumab therapy, most adverse events are reversible with a prompt immunosuppression. Studies investigating nivolumab in combination with other agents are ongoing.

Expert commentary: Nivolumab represents a significant breakthrough in the treatment of advanced NSCLC. Its therapeutic role for NSCLC may soon expand to include consolidation or maintenance setting. Furthermore, several clinical trials investigating the combination of nivolumab with other immunologic or non-immunologic treatments are ongoing and these will likely result in additional roles of nivolumab in NSCLC.     

The safety and efficacy of ramucirumab in combination with docetaxel in the treatment of lung cancer

Introduction: Angiogenesis is critical for tumor growth, proliferation and metastasis with the crucial role of Vascular Endothelial Growth factor (VEGF) pathway. Ramucirumab is a monoclonal antibody that specifically targets the extracellular domain of Vascular Endothelial Growth Factor Receptor 2.

Areas covered: We performed a search on Medline to browse the current literature on Ramucirumab and anti-angiogenic agents, for the treatment of NSCLC. The REVEL study demonstrated a significant improvement of response rate, progression-free survival and overall survival by adding ramucirumab to docetaxel compared to docetaxel plus a placebo in second-line treatment of advanced non-small cell lung cancer, irrespective of histology, with an acceptable safety profile. This article has for objective to summarize efficacy and safety data of the use of ramucirumab in combination with docetaxel in second line in NSCLC.

Expert commentary: REVEL constitutes the first significant advance in second-line setting for patients eligible to anti-angiogenic therapy. The landscape of post-platinum therapy in NSCLC is considerably evolving and the role of ramucirumab or other anti-angiogenic agents as nintedanib in this setting has to be discussed for each patient with other available treatment options, among which immune checkpoints inhibitors, as well as the best treatment sequence.