[Role of the Sonic Hedgehog pathway in thoracic cancers]

INTRODUCTION

Sonic Hedgehog (Shh) pathway is physiologically activated during embryogenesis and development. It plays a role in idiopathic lung fibrosis and is also activated in several solid cancers.

STATE OF THE ART

Shh pathway is reactivated in thoracic cancers, as small cell lung carcinoma, non-small cell lung carcinoma and malignant pleural mesothelioma. Shh pathway is associated with cancer stem cells and seems to have a crucial role in tumor proliferation, aggressiveness and chemoresistance in these cancers. This review describes the activation mode of Shh pathway in thoracic cancers and its role in small cell lung carcinoma, non-small cell lung carcinoma and malignant pleural mesothelioma, using in vitro and in vivo models. Notably, data from literature show that inhibition of Shh pathway has an antitumor action and sensitizes to chemotherapy.

PERSPECTIVES

These results incite to develop targeted therapies against Shh pathway in the treatment of thoracic cancers.

A randomized phase II study of the MEK1/MEK2 inhibitor trametinib (GSK1120212) compared with docetaxel in KRAS-mutant advanced non-small-cell lung cancer (NSCLC)†

BACKGROUND

KRAS mutations are detected in 25% of non-small-cell lung cancer (NSCLC) and no targeted therapies are approved for this subset population. Trametinib, a selective allosteric inhibitor of MEK1/MEK2, demonstrated preclinical and clinical activity in KRAS-mutant NSCLC. We report a phase II trial comparing trametinib with docetaxel in patients with advanced KRAS-mutant NSCLC.

PATIENTS AND METHODS

Eligible patients with histologically confirmed KRAS-mutant NSCLC previously treated with one prior platinum-based chemotherapy were randomly assigned in a ratio of 2 : 1 to trametinib (2 mg orally once daily) or docetaxel (75 mg/m(2) i.v. every 3 weeks). Crossover to the other arm after disease progression was allowed. Primary end point was progression-free survival (PFS). The study was prematurely terminated after the interim analysis of 92 PFS events, which showed the comparison of trametinib versus docetaxel for PFS crossed the futility boundary.

RESULTS

One hundred and twenty-nine patients with KRAS-mutant NSCLC were randomized; of which, 86 patients received trametinib and 43 received docetaxel. Median PFS was 12 weeks in the trametinib arm and 11 weeks in the docetaxel arm (hazard ratio [HR] 1.14; 95% CI 0.75-1.75; P = 0.5197). Median overall survival, while the data are immature, was 8 months in the trametinib arm and was not reached in the docetaxel arm (HR 0.97; 95% CI 0.52-1.83; P = 0.934). There were 10 (12%) partial responses (PRs) in the trametinib arm and 5 (12%) PRs in the docetaxel arm (P = 1.0000). The most frequent adverse events (AEs) in ≥20% of trametinib patients were rash, diarrhea, nausea, vomiting, and fatigue. The most frequent grade 3 treatment-related AEs in the trametinib arm were hypertension, rash, diarrhea, and asthenia.

CONCLUSION

Trametinib showed similar PFS and a response rate as docetaxel in patients with previously treated KRAS-mutant-positive NSCLC.

CLINICALTRIALSGOV REGISTRATION NUMBER

NCT01362296.

[Pulmonary manifestations in HIV-infected patients: a diagnostic approach]

The spectrum of pulmonary diseases that can affect human immunodeficiency virus (HIV)-infected patients is wide and includes both HIV and non-HIV-related conditions. Opportunistic infections and neoplasms remain a major concern even in the current era of combination antiretroviral therapy. Although these diseases have characteristic clinical and radiological features, there can be considerable variation in these depending on the patient's CD4 lymphocyte count. The patient's history, physical examination, CD4 count and chest radiograph features must be considered in establishing an appropriate diagnostic algorithm. In this article, we propose different diagnostic approaches HIV infected to patients with respiratory symptoms depending on their clinico-radiological pattern.

2014 update on non-small cell lung cancer (excluding diagnosis)

Lung cancer (LC) is a major public health issue because of its frequency, but especially because of the severity of this disease. The epidemiology has changed with an increased incidence in non-smokers and women. The ATS/ERS/IASLC classification of adenocarcinomas was modified in 2011, and they are now the most frequent histological subtype. More than half the cases of LC are diagnosed at the metastatic stage. Biopsies must provide tissue samples that are quantitatively large enough and of a good enough quality for diagnosis and to search for biomarkers. When the cancer seems to be localized, precise staging must be obtained. Treatment is based on the TNM classification. In localized stages, lobectomy associated with lymph node dissection is the standard therapy. Intraoperative chemotherapy improves survival in case of lymph node infiltration. Stereotactic radiation therapy and radiofrequency can be considered as specific cases. In cases with local progression, treatment is more controversial. In the presence of metastases, the goal is not a cure, but improving survival and quality of life. Numerous advances have been made with personalized treatment, (in particular in relation to the histological type and oncogenic addiction in tumors, access to new drugs, and improved management). Clinical research in thoracic cancer is very active. The fight against tobacco should remain a priority.

Rare EGFR exon 18 and exon 20 mutations in non-small-cell lung cancer on 10 117 patients: a multicentre observational study by the French ERMETIC-IFCT network

BACKGROUND

There is scarce data available about epidermal growth factor receptor (EGFR) mutations other than common exon 19 deletions and exon 21 (L858R) mutations.

PATIENTS AND METHODS

EGFR exon 18 and/or exon 20 mutations were collected from 10 117 non-small-cell lung cancer (NSCLC) samples analysed at 15 French National Cancer Institute (INCa)-platforms of the ERMETIC-IFCT network.

RESULTS

Between 2008 and 2011, 1047 (10%) samples were EGFR-mutated, 102 (10%) with rare mutations: 41 (4%) in exon 18, 49 (5%) in exon 20, and 12 (1%) with other EGFR mutations. Exon 20 mutations were related to never-smoker status, when compared with exon 18 mutations (P < 0.001). Median overall survival (OS) of metastatic disease was 21 months [95% confidence interval (CI) 12-24], worse in smokers than in non-smoker patients with exon 20 mutations (12 versus 21 months; hazard ratio [HR] for death 0.27, 95% CI 0.08-0.87, P = 0.03). Under EGFR-tyrosine kinase inhibitors (TKIs), median OS was 14 months (95% CI 6-21); disease control rate was better for complex mutations (6 of 7, 86%) than for single mutations (16 of 40, 40%) (P = 0.03).

CONCLUSIONS

Rare EGFR-mutated NSCLCs are heterogeneous, with resistance of distal exon 20 insertions and better sensitivity of exon 18 or complex mutations to EGFR-TKIs, probably requiring individual assessment.

[Lung cancer and HIV infection]

AIDS was the cause of the majority of deaths from HIV infection before 1996 but since the introduction of antiretroviral therapies the causes of mortality have changed considerably. In 2010, 75 % of deaths were due to diseases other than AIDS, the majority being cancers. Lung cancer is the most common in terms of both incidence and mortality. It shows specific features when compared to the general population: there is an excess risk due to heavy smoking but also probably due to immunosuppression. The age of onset is younger and the prognosis worse than in the general population. Management is difficult, partly due to the aggressive nature of the tumor and partly to co-morbidities and potential interactions between anticancer and antiretroviral therapies. A phase II therapeutic trial (IFCT-CHIVA 1001) is under way nationally.