Surgical resection of primary tumors improved the prognosis of patients with bone metastasis of non-small cell lung cancer: a population-based and propensity score-matched study

Premetastatic Niche Mimicking Bone-On-A-Chip: A Microfluidic Platform to Study Bone Metastasis in Cancer Patients

Primary cancer modulates the bone microenvironment to sow the seeds of dormancy and metastasis in tumor cells, leading to multiple organ metastasis and death. In this study, 3D printing and bone-on-a-chip (BOC) are combined to develop a BOC platform that mimics the pre-metastatic niches (PMNs) and facilitates elucidation of the interactions between bone-resident cells and metastatic tumor cells under the influence of primary cancer. Photocrosslinkable gelatin methacrylate (GelMA) is used as a 3D culturing hydrogel to encapsulate cells, and circulate tumor culture medium (CM) adjacent to the hydrogel to verify the critical role of mesenchymal stem cells (MSCs) and osteoclasts (RAW264.7s). Three niches: the dormancy niche, the perivascular niche, and the "vicious cycle" niche, are devised to recapitulate bone metastasis in one chip with high cell viability and excellent nutrient exchange. With respect to tumor dormancy and reactivation, the invadopodia formation of A549 lung cancer cells in communication with MSCs and RAW264.7 via the cortactin pathway is researched. As a proof of concept, the functionality and practicality of the platform are demonstrated by analyzing the invadopodia formation and the influence of various cells, and the establishment of the dynamic niches paves the way to understanding PMN formation and related drug discovery.

Survival benefit of resection surgery for lung adenocarcinoma with bone metastases and a post-operative prognosis nomogram establishment and validation

Background

Surgical resection is not usually recommended for lung adenocarcinoma (LUAD) patients with bone metastases. However, the criteria for surgery are constantly being adjusted and there is a need to focus on the prognostic role of cancer-directed surgery (CDS) for bone metastatic LUAD patients investigate the factors influencing survival of CDS. We determined the survival benefit of CDS for LUAD patients with bone metastases and to develop a prognostic nomogram to predict overall survival (OS) for patients after surgery.

Methods

LUAD patients with bone metastases from the Surveillance, Epidemiology, and End Results (SEER) database between 2010-2015 were included and divided into CDS and non-CDS groups. The propensity score matching (PSM) was used to balance baseline characteristics. We used Kaplan-Meier curves and log-rank tests to compare cancer-specific survival (CSS) and OS between the two groups. Patients underwent CDS were randomly divided into training and validation cohorts to develop and validate a nomogram model to predict postoperative prognosis outcome-OS.

Results

Patients who underwent CDS had a better OS and CSS than those who did not underwent CDS (e.g., 1-year OS rate: 56.9% vs. 30.1%). Independent prognostic factors were selected by Cox regression analysis for CDS patients including age, sex, race, histological grade, N stage, and chemotherapy, and a nomogram was constructed to predict 1-, 2-, and 3-year OS after surgery according to the prognostic factors. The calibration curve and receiver operating characteristic (ROC) curve for the nomogram showed the model had a high predictive accuracy. [Area under the curve (AUC) at 1, 2, and 3 years in the training cohort were 0.735, 0.756 and 0.782, and in the validation cohort were 0.703, 0.758 and 0.836, respectively]. In addition, patients were divided into high-risk and low-risk groups based on prognostic scores, and Kaplan-Meier curves showed significant differences in prognosis between the two groups.

Conclusions

These results indicated that patients with bone metastasis of LUAD received survival benefit from CDS. The prognostic nomograms could assist clinicians in specifying individualized assessments, but further research is needed.

The Prognostic Impact of Lymph Node Dissection on Primary Tumor Resection for Stage IV Non-Small Cell Lung Cancer: A Population-Based Study

Objective

Selected patients with stage IV non–small cell lung cancer (NSCLC) who underwent primary tumor resection have witnessed a survival benefit. Whether additional lymph node dissection (LND) would result in a better effect remain unknown. We investigated the prognostic impact of LND on patients with stage IV NSCLC who received primary tumor resection (PTR).

Methods

Patients with stage IV NSCLC who underwent PTR were identified from the Surveillance, Epidemiology, and End Results database from 2004 to 2016. Propensity-score matching was performed to minimize the confounding effect, and lung cancer-specific survival (CSS) and overall survival (OS) were compared after matching. Multivariable Cox regression was used to identify prognostic factors and to adjust for covariates in subgroup analysis. The effect of the number of lymph nodes examined on the CSS was evaluated by repeating the Cox analysis in a binary method.

Results

A total of 4,114 patients with stage IV NSCLC who receive surgery met our criteria, of which 2,622 (63.73%) underwent LND and 628 patients were identified 1:1 in LND and non-LND groups after matching. Compared with the non-LND group, the LND group had a longer CSS (median: 23 vs. 16 months, p < 0.001) and OS (median: 21 vs. 15 months, p < 0.001). Multivariable regression showed that LND was independently associated with favorable CCS [hazard ratio (HR) = 0.78, 95% confidence interval (CI) 0.69–0.89, P < 0.001] and OS (HR = 0.79, 95% CI 0.70–0.89, P < 0.001). Subgroup analysis suggested that LND is an independent favorable predictor to survival in the surgical patients who were older age (>60 years old), female, T3-4, N0, and M1a stage and those who underwent sublobar resection. In addition, a statistically significant CCS benefit was associated with an increasing number of lymph nodes examined through 25 lymph nodes.

Conclusions

LND with a certain range of lymph nodes number examined was associated with improved survival for patients with stage IV NSCLC who received primary tumor resection. The results may have implications for guidelines on lymph nodes management in selective advanced NSCLC for surgery.