Factors associated with early lung cancer mortality: a systematic review

ABSTRACT

Introduction: Despite recent therapeutic advances, lung cancer remains the primary cause of cancer deaths worldwide, and early lung mortality was poorly studied.

Area covered: Early lung-cancer mortality reflects local therapy (surgery or radiotherapy) impact (localized forms), and metastatic disease evolution, comorbidities and healthcare-system accessibility. The definition of early lung cancer mortality is not consensual; thresholds range from 1 to 12 months post-diagnosis. This systematic review was undertaken to identify and analyze factors significantly associated with early lung cancer mortality. Age, male sex, non-adenocarcinoma histology, advanced stage at diagnosis and ECOG performance status are the main clinical factors of early lung cancer mortality. Active/ex-smoking also seems to favor early mortality, despite heterogeneous definitions of smoker status. For radio-chemotherapy treated locally advance disease, the early mortality rate increases according to tumor volume. Less well studied, socioeconomic characteristics (rurality and social deprivation index) yielded contradictory results, partially because definitions vary over studies. However, early lung cancer mortality is significantly higher for lower socioeconomic class patients.

Expert opinion: Prospective, observational, general population studies are needed to better evaluate early lung-cancer mortality. International consensus concerning the patient-, disease- or healthcare system-linked factors of interest to be collected would facilitate comparisons among countries.

KEYWORDS:

• Lung cancer
• mortality
• prognosis
• survival
• epidemiology

Article highlights

• Lung cancer is the primary cause of death to cancer worldwide.

• Its mortality rate has remained high and, despite recent therapeutic advances, has declined only slightly.

• Early mortality has not yet been clearly defined, with thresholds varying from one to 12 months after diagnosis, depending on the study.

• Age, male sex, elevated performance status, advanced stage, non-adenocarcinoma histology and active smoking are clinical factors contributing to early death in metastatic setting.

• In locally advanced disease, tumor size and volume are also associated with higher early mortality rates.

• The impact of socioeconomic characteristics on early mortality has not been found in all studies.

• Harmonization of the definition of early lung cancer mortality is desirable, so as to facilitate use of this indicator to more easily compare studies.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper received no funding.