What is the role for surgery in patients with stage III non-small cell lung cancer?

[Effect of PI3K/AKT pathway on cisplatin resistance in non-small cell lung cancer]

Accumulating evidences indicate that aberrant activation of PI3K/AKT pathway in non-small cell lung cancer plays a vital role in tumor cell proliferation,apoptosis, and survival including drug resistance. Cisplatin as first-line chemotherapy are in widespread clinical use in patients with non-small cell lung cancer, however, the development of cisplatin resistance significantly impedes its clinic efficacy. Cisplatin resistance is a complicated process that various mechanisms participating in to interact, of which PI3K/AKT pathway keeping sustained activated is one of the most important reasons. This article reviewed the progress of research on the relationship between PI3K/AKT pathway and cisplatin resistance.

Associations between single-nucleotide polymorphisms in the PI3K-PTEN-AKT-mTOR pathway and increased risk of brain metastasis in patients with non-small cell lung cancer

PURPOSE

Non-small cell lung cancer (NSCLC) metastasizes fairly often to the brain, but identifying which patients will develop brain metastases is problematic. The phosphoinositide 3-kinase (PI3K)-AKT-mTOR signaling pathway is important in the control of cell growth, tumorigenesis, and cell invasion. We hypothesized that genotype variants in this pathway could predict brain metastasis in patients with NSCLC.

METHODS

We genotyped 16 single-nucleotide polymorphisms (SNP) in five core genes (PIK3CA, PTEN, AKT1, AKT2, and FRAP1) by using DNA from blood samples of 317 patients with NSCLC, and evaluated potential associations with the subsequent development of brain metastasis, the cumulative incidence of which was estimated with Kaplan-Meier analysis. Multivariate Cox regression analysis was used to analyze correlations between genotype variants and the occurrence of brain metastasis.

RESULTS

In analysis of individual SNPs, the GT/GG genotype of AKT1: rs2498804, CT/TT genotype of AKT1: rs2494732, and AG/AA genotype of PIK3CA: rs2699887 were associated with higher risk of brain metastasis at 24-month follow-up [respective HRs, 1.860, 95% confidence interval (CI) 1.199-2.885, P = 0.006; HR 1.902, 95% CI 1.259-2.875, P = 0.002; and HR 1.933, 95% CI 1.168-3.200, P = 0.010]. We further found that these SNPs had a cumulative effect on brain metastasis risk, with that risk being highest for patients carrying both of these unfavorable genotypes (P = 0.003).

CONCLUSIONS

Confirmation of our findings, the first to indicate that genetic variations in PI3K-AKT-mTOR can predict brain metastasis, in prospective studies would facilitate stratification of patients for brain metastasis prevention trials.

Genetic variants in the PI3K/PTEN/AKT/mTOR pathway predict platinum-based chemotherapy response of advanced non-small cell lung cancers in a Chinese population

OBJECTIVE

The PI3K/PTEN/AKT/mTOR signaling pathway has been implicated in resistance to cisplatin. In the current study, we determined whether common genetic variations in this pathway are associated with platinum-based chemotherapy response and clinical outcome in advanced non-small cell lung cancer (NSCLC) patients.

METHODS

Seven common single nucleotide polymorphisms (SNPs) in core genes of this pathway were genotyped in 199 patients and analyzed for associations with chemotherapy response, progression-free survival (PFS) and overall survival (OS).

RESULTS

Logistic regression analysis revealed an association between AKT1 rs2494752 and response to treatment. Patients carrying heterozygous AG had an increased risk of disease progression after two cycles of platinum-based chemotherapy compared to those with AA genotype (Adjusted odds ratio (OR)=2.18, 95% confidence interval (CI): 1.00-4.77, which remained significant in the stratified analyses). However, log-rank test and cox regression detected no association between these polymorphisms in the PI3K pathway genes and survival in advanced NSCLC patients.

CONCLUSIONS

Our findings suggest that genetic variants in the PI3K/PTEN/AKT/mTOR pathway may predict platinum-based chemotherapy response in advanced NSCLC patients in a Chinese population.

The multimodal management of locally advanced N2 non-small cell lung cancer: is there a role for surgical resection? A single institution's experience

BACKGROUND

The management of operable locally advanced N2 non-small cell lung cancer (NSCLC) is a controversial topic. Concurrent chemoradiation (CT-RT) is considered the standard of care for inoperable or unresectable patients, but the role of trimodality treatment remains controversial. We present our institution's experience with the management of stage III (N2) NSCLC patients, analyzing whether the addition of surgery improves survival when compared with definitive CT-RT alone.

METHODS

From 1996 to 2006, 72 N2 NSCLC patients were treated. Thirty-four patients received cisplatin-based induction chemotherapy, followed by paclitaxel-cisplatin CT-RT, and 38 patients underwent surgery preceded by induction and/or followed by adjuvant therapy. Survival curves were estimated by Kaplan-Meier analysis, and the differences were assessed with the log-rank test.

RESULTS

Most of the patients (87 %) were men. The median age was 59 years. A statistically significant association between T3-T4c and definitive CT-RT as well as between T1-T2c and surgery was noted (p < 0.0001). After a median follow-up period of 35 months, the median overall survival (OS) was 42 months for the surgery group versus 41 months for the CT-RT patients (p = 0.590). The median progression-free survival (PFS) was 14 months after surgery and 25 months after CT-RT (p = 0.933). Responders to radical CT-RT had a better OS than non-responders (43 vs. 17 months, respectively, p = 0.011). No significant differences were found in the OS or PFS between the pN0 [14 (37.8 %) patients] and non-pN0 patients at thoracotomy. Three treatment-related deaths (7.8 %) were observed in the surgical cohort and none in the CT-RT group.

CONCLUSIONS

The addition of surgery did not render a median OS or PFS benefit when compared with CT-RT alone in our series of stage III-N2 NSCLC patients, in accordance with previously published data. However, responses to CT-RT had a greater impact in terms of OS and PFS. Although the patients selected for management including surgery showed a favorable T clinical staging in comparison to patients exclusively treated with definitive CT-RT, similar survival outcomes were found.

Endobronchial ultrasound-guided transbronchial needle aspiration cytology: a state of the art review

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a recently developed, accurate, safe and cost-effective technique that allows sampling of mediastinal lymph nodes and peribronchial lesions including pulmonary and mediastinal lesions. Its major indications are the nodal staging of non-small cell carcinomas of the lung, their restaging after chemotherapy and/or radiation, the diagnosis of sarcoidosis and of metastases from extrathoracic malignancies, and the diagnosis of mediastinal lymphadenopathy and masses of unknown aetiology. From our experience at the University of Minnesota and a comprehensive review of the literature, we discuss technical aspects of the procedure, its advantages and limitations in comparison with other methods of sampling mediastinal lymph nodes, focusing on the role of the cytopathologist in ensuring the effectiveness of the procedure. An algorithmic approach to the cytological diagnosis, starting with the determination of the adequacy of the sample, is also presented.