Usefulness of complementary next-generation sequencing and quantitative immunohistochemistry panels for predicting brain metastases and selecting treatment outcomes of non-small cell lung cancer

Immune related biomarkers for cancer metastasis to the brain

Brain metastasis accounts for a large number of cancer-related deaths. The host immune system, involved at each step of the metastatic cascade, plays an important role in both the initiation of the brain metastasis and their treatment responses to various modalities, through either local and or systemic effect. However, few reliable immune biomarkers have been identified in predicting the development and the treatment outcome in patients with cancer brain metastasis. Here, we provide a focused perspective of immune related biomarkers for cancer metastasis to the brain and a thorough discussion of the potential utilization of specific biomarkers such as tumor mutation burden (TMB), genetic markers, circulating and tumor-infiltrating immune cells, cytokines, in predicting the brain disease progression and regression after therapeutic intervention. We hope to inspire the field to extend the research and establish practical guidelines for developing and validating immune related biomarkers to provide personalized treatment and improve treatment outcomes in patients with metastatic brain cancers.

Survival and prognostic factors in patients undergoing the resection of solitary brain metastasis from non-small cell lung cancer: a retrospective cohort study

BACKGROUND

Neurosurgery is the standard of care for resectable solitary brain metastasis (BM) from non-small cell lung cancer (NSCLC), but still with a poor outcome. Postoperative whole-brain radiotherapy (WBRT) was reported to reduce local recurrence, whether it could prolong survival was uncertain. In this study, we attempted to evaluate WBRT and other prognostic for overall survival (OS) in these patients.

METHODS

In this retrospective study, NSCLC patients with a solitary BM and controlled primary tumor who underwent neurosurgical resection were selected from the medical records database between January 2014 and December 2018. Clinical data, disease control/progression results and survival outcomes were obtained from the medical records, regular outpatient follow-up and telephone interviews. Univariable and multivariable Cox analyses of potential prognostic factors including patients' characteristics, BM features, tissue-based parameters and postoperative treatments were conducted. OS was illustrated using Kaplan-Meier curves, and group differences were assessed using the log-rank test. The subgroup analysis compared each variable between the WBRT group and the untreated control by the hazard ratio and its 95% confidence interval (CI).

RESULTS

A total of 94 patients were included, with a median OS of 812 days. Univariable analysis showed that postoperative WBRT and targeted therapy were associated with OS. Multivariable analysis demonstrated that postoperative WBRT [P<0.001, hazard ratio (HR) 0.357], chemotherapy (P=0.008, HR 0.512), targeted therapy (P<0.001, HR 0.265), and smaller tumor size (P=0.018, HR 0.553) were independent prognostic factors for prolonged OS. However, tissue-based parameters (Ki67 tumor cell proliferation index, epidermal growth factor receptor, and checkpoint levels) were identified as statistically insignificant factors. In the subgroup analysis, the beneficial effect of WBRT was only observed in patients that did not receive systematic treatments.

CONCLUSIONS

Postoperative WBRT and systematic treatments after solitary BM resection improve the prognosis of NSCLC patients with a controlled primary tumor. Postoperative WBRT could be considered, especially for those who not receive systematic chemotherapy or targeted therapy treatments, as they might be more likely to benefit from it.

Update on adjuvant therapy in completely resected NSCLC patients

In patients with completely resected non‐small cell lung cancer (NSCLC), postoperative adjuvant chemotherapy has been associated with improvement in survival by minimizing the risk of recurrence. For years, systemic chemotherapy including platinum based regimen has been a mainstay treatment modality of adjuvant treatment after complete resection. ADAURA study showed that among completely resected IB to IIIA NSCLC, disease‐free survival was significantly better in patients under adjuvant osimertinib than a placebo group. After the advent of a variety of new treatment regimens, such as third generation TKI and immunotherapy, the landscape of postoperative adjuvant treatment has been changing. In this review, we discuss some key issues regarding choice of adjuvant treatment after complete resection in NSCLC, and provide further updates on recent advances in treatment modalities.

Simultaneous analysis of ALK, RET, and ROS1 gene fusions by NanoString in Brazilian lung adenocarcinoma patients

Background

Gene fusions have been successfully employed as therapeutic targets for lung adenocarcinoma. However, tissue availability for molecular testing of multiples alterations is frequently unfeasible. We aimed to detect the presence of ALK, RET, and ROS1 rearrangements by a RNA-based single assay in Brazilian lung adenocarcinomas and to associate with clinicopathological features and genetic ancestry.

Methods

From a FFPE series of 444 molecularly characterized lung adenocarcinomas, 253 EGFR/KRAS wild-type cases were eligible for gene rearrangement analysis. Following RNA isolation, ALK, RET, and ROS1 rearrangements were simultaneously analyzed employing the ElementsXT Custom panel (NanoString Technologies). Rearrangements were further associated with clinicopathological features and genetic ancestry of the patients.

Results

The NanoString platform was performed in subset of 142 cases. Gene fusion results were conclusive for 94.4% (n=134) cases (failure rate =5.6%). ALK rearrangements were observed in 21 out of 134 cases, and associated with younger, never smokers, metastatic disease, and metastases in the central nervous system. RET and ROS1 fusions were detected in two and one out of 134 cases, respectively. Genetic ancestry was not associated with gene fusions. Overall, considering all cases for which a molecular analysis was conclusive (EGFR/KRAS/ALK/RET/ROS1), ALK fusions frequency was observed in 6.5% (21/325), RET in 0.6% (2/325), and ROS1 in 0.3% (1/325).

Conclusions

This study successfully used a RNA-based single assay for the simultaneous analysis of ALK, RET, and ROS1 fusions employing routine biopsies from Brazilian patients lung adenocarcinoma allowing an extensive molecular testing for actionable rearrangements contributing to guide clinical strategies.

Variants in Epithelial-Mesenchymal Transition and Immune Checkpoint Genes Are Associated With Immune Cell Profiles and Predict Survival in Non-Small Cell Lung Cancer

CONTEXT.—

Identification of gene mutations that are indicative of epithelial-mesenchymal transition and a noninflammatory immune phenotype may be important for predicting response to immune checkpoint inhibitors.

OBJECTIVE.—

To evaluate the utility of multiplex immunofluorescence for immune profiling and to determine the relationships among tumor immune checkpoint and epithelial-mesenchymal transition genomic profiles and the clinical outcomes of patients with nonmetastatic non-small cell lung cancer.

DESIGN.—

Tissue microarrays containing 164 primary tumor specimens from patients with stages I to IIIA non-small cell lung carcinoma were examined by multiplex immunofluorescence and image analysis to determine the expression of programmed death ligand-1 (PD-L1) on malignant cells, CD68+ macrophages, and cells expressing the immune markers CD3, CD8, CD57, CD45RO, FOXP3, PD-1, and CD20. Immune phenotype data were tested for correlations with clinicopathologic characteristics, somatic and germline genetic variants, and outcome.

RESULTS.—

A high percentage of PD-L1+ malignant cells was associated with clinicopathologic characteristics, and high density of CD3+PD-1+ T cells was associated with metastasis, suggesting that these phenotypes may be clinically useful to identify patients who will likely benefit from immunotherapy. We also found that ZEB2 mutations were a proxy for immunologic ignorance and immune tolerance microenvironments and may predict response to checkpoint inhibitors. A multivariate Cox regression model predicted a lower risk of death for patients with a high density of CD3+CD45RO+ memory T cells, carriers of allele G of CTLA4 variant rs231775, and those whose tumors do not have ZEB2 mutations.

CONCLUSIONS.—

Genetic variants in epithelial-mesenchymal transition and immune checkpoint genes are associated with immune cell profiles and may predict patient outcomes and response to immune checkpoint blockade.