17PD - Patterns of lung cancer metastasis in the US population

Date 06 May 2017
Event ELCC 2017
Session Epidemiology and innovations in biomarker development
Topics Cancer Aetiology, Epidemiology, Prevention
Lung and other Thoracic Tumours
Presenter Mohamed Hendawi
Citation Annals of Oncology (2017) 28 (suppl_2): ii6-ii8. 10.1093/annonc/mdx087
Authors M. Hendawi
  • Ohio State Univ Medical Center, 43212 - Columbus/US

Abstract

Background

Lung cancers mostly present at a clinically advanced stage. Predicting the invasiveness of tumors might help in planning treatment and prophylaxis. We aim to investigate the patterns of lung cancer metastasis and determine possible clinical predictors of those patterns in population based study.

Methods

The records of all patients (2010-2013) were extracted from SEER database of the National Cancer Institute. Data was extracted to SPSS. Univariate and multivariate logistic regression were used for analysis.

Results

We have identified 76254 (54.5%M, 45.5F) patients with metastatic lung cancer (2010-2013).17% were small cell tumors (SCLC), while 83% of tumors were non-small cell tumors (NSCLC). Tumor was found more frequently on the right (54%) than the left (38%), and was bilateral in 8% of cases. Our analysis showed that NSCLC had higher rates of metastasis to bone than SCLC (37% Vs 34%) (P < 0.001, 95% CI: 1.097-1.190), SCLC had higher rates of metastasis to liver than NSCLC (46% Vs 20%) (p < 0.001 95%CI: 0.27-0.29), both SCLC and NCLC had almost similar rates of brain metastasis at the time of diagnosis (25% Vs 26%, respectively) (P = 0.003, 95% CI: 1.024-1.120). Following adenocarcinoma and small cell, squamous cell histology was 3rd most common tumor histology for both brain and liver metastasis. Although rare, carcinoid tumor had high rates of metastasis to brain at diagnosis (44.8%). Predictors for liver metastasis were small cell and adenocarcinoma histology (p < 0.001, 95% CI:0 .245-0.304), Tumors with upper lobe location (P = 0.028, 95% CI: 0.839-0.990), and high grade tumors (P < 0.001, 95% CI: 1.334-1.618). Predictors for metastasis to brain were advanced age at diagnosis (P < 0.001, 95% CI: 0.970 -0.976), Adenocarcinoma and small cell histology (P < 0.001, 95% CI: 1.254-1.561), Lower lobe, and main bronchus locations (p = 0.004, 95% CI: 0.689-0.930), and tumors of higher grade (P < 0.001, 95%CI: 1.250-1.463).

Conclusions

Lung cancer subtypes are associated with distinct patterns of metastatic spread. SCLC has significantly higher rates of liver metastases, while NSCLC has higher rates of bone metastasis. Further investigation needed to evaluate the role of primary tumor location on metastatic behavior of lung cancer.

Clinical trial identification

Legal entity responsible for the study

Mohamed Hendawi

Funding

N/A

Disclosure

The author has declared no conflicts of interest.