Single organ metastatic disease and local disease status, prognostic factors for overall survival in stage IV non-small cell lung cancer: Results from a population-based study.
OBJECTIVE
To analyse the prognostic impact on overall survival (OS) of single versus multiple organ metastases, organ affected, and local disease status in a population based stage IV non-small cell lung cancer (NSCLC) cohort.


METHODS
In this observational study, data were analysed of all histologically confirmed stage IV NSCLC patients diagnosed between 1 January 2006 and 31 December 2012 registered in the Netherlands Cancer Registry. Location of metastases before treatment was registered. Multivariable survival analyses [age, gender, histology, M-status, local disease status, number of involved organs, actual organ affected] were performed for all patients and for an (18)fluorodeoxyglucose-positron emission tomography ((18)FDG-PET)-staged subgroup.


RESULTS
11,094 patients were selected: 60% male, mean age 65 years, 73% adenocarcinoma. Median OS for 1 (N = 5676), 2 (N = 3280), and ⩾ 3 (N = 2138) metastatically affected organs was 6.7, 4.3, 2.8 months, respectively (p < 0.001). Hazard ratio (HR) for 2 versus 1 organ(s) was 1.33 (p < 0.001), for ⩾ 3 versus 1 organ(s) 1.91 (p < 0.001). Results were confirmed in the (18)FDG-PET-staged cohort (N = 1517): patients with single organ versus 2 and ⩾ 3 organ metastases had higher OS (8.6, 5.7, 3.8 months, HR 1.40 and 2.17, respectively, p < 0.001). In single organ metastases, OS for low versus high TN-status was 8.5 versus 6.5 months [HR 1.40 (p < 0 .001)]. (18)FDG-PET-staged single organ metastases patients with low TN-status had a superior OS than those with high TN-status (11.6 versus 8.2 months, HR 1.62, p < 0.001).


CONCLUSIONS
Patients with single organ metastases stage IV NSCLC have a favourable prognosis, especially in combination with low TN status. They have to be regarded as a separate subgroup of stage IV disease.
Department of Pulmonary Diseases, GROW - School for Oncology and Developmental Biology, Maastricht University Medical Center+, Maastricht, The Netherlands. Electronic address: Lizza.hendriks@mumc.nl.
L E
LE
Hendriks
Department of Pulmonary Diseases, GROW - School for Oncology and Developmental Biology, Maastricht University Medical Center+, Maastricht, The Netherlands. Electronic address: j.derks@maastrichtuniversity.nl.
J L
JL
Derks
Department of Pulmonary Diseases, Clatterbridge Cancer Centre, Liverpool Heart & Chest Hospital, University of Liverpool, Liverpool, UK. Electronic address: pepostmus@gmail.com.
P E
PE
Postmus
Department of Registry and Research, Comprehensive Cancer Centre the Netherlands, Rotterdam, The Netherlands. Electronic address: R.Damhuis@iknl.nl.
R A
RA
Damhuis
Department of Radiation Oncology (MAASTRO Clinic), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Center+, Maastricht, The Netherlands. Electronic address: Ruud.houben@maastro.nl.
R M A
RM
Houben
Department of Radiation Oncology, University Hospital and Medical Faculty Carl Gustav Carus of TU Dresden, Fetscherstr. 74, 01307 Dresden, Germany. Electronic address: Esther.Troost@uniklinikum-dresden.de.
E G C
EG
Troost
Department of Pulmonary Diseases, GROW - School for Oncology and Developmental Biology, Maastricht University Medical Center+, Maastricht, The Netherlands. Electronic address: m.hochstenbag@mumc.nl.
M M
MM
Hochstenbag
Department of Thoracic Oncology, The Netherlands Cancer Institute, Amsterdam, The Netherlands. Electronic address: E.smit@nki.nl.
E F
EF
Smit
Department of Pulmonary Diseases, GROW - School for Oncology and Developmental Biology, Maastricht University Medical Center+, Maastricht, The Netherlands. Electronic address: a.dingemans@mumc.nl.
A-M C
AM
Dingemans
D000230:Adenocarcinoma / Q000473:pathology*; D000368:Aged; D001859:Bone Neoplasms / Q000556:secondary; D001932:Brain Neoplasms / Q000556:secondary; D002289:Carcinoma, Non-Small-Cell Lung / Q000473:pathology*; D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D053208:Kaplan-Meier Estimate; D008113:Liver Neoplasms / Q000556:secondary; D008175:Lung Neoplasms / Q000473:pathology*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods / Q000706:statistics & numerical data; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography; D011379:Prognosis; D016016:Proportional Hazards Models; D014057:Tomography, X-Ray Computed
D019788:Fluorodeoxyglucose F18
Local disease status; Metastases; Non-small cell lung cancer; Prognosis; Stage IV