Sequential screening for lung cancer in a high-risk group

Spiro SG, Shah PL, Rintoul RC, et al.
Sequential screening for lung cancer in a high-risk group: randomised con-trolled trial: LungSEARCH: a randomised controlled trial of Surveillance us-ing sputum and imaging for the EARly detection of lung Cancer in a High-risk group.
Eur Respir J. 2019 Oct 17;54(4).

Abstract
BACKGROUND: Low-dose computed tomography (LDCT) screening detects early-stage lung cancer and reduces mortality. We proposed a sequential approach targeted to a high-risk group as a potentially efficient screening strategy.

METHODS: LungSEARCH was a national multicentre randomised trial. Current/ex-smokers with mild/moderate chronic obstructive pulmonary disease (COPD) were allocated (1:1) to have 5 years surveil-lance or not. Screened participants provided annual sputum samples for cytology and cytometry, and if abnormal offered annual LDCT and autofluorescence bronchoscopy (AFB). Those with normal sputum provided annual samples. The primary end-point was the percentage of lung cancers diagnosed at stage I/II (nonsmall cell) or limited disease (small cell).

RESULTS: 1568 participants were randomised during 2007-2011 from 10 UK centres. 85.2% of those screened provided an adequate baseline sputum sample. There were 42 lung cancers among 785 screened individuals and 36 lung cancers among 783 controls. 54.8% (23 out of 42) of screened individuals versus 45.2% (14 out of 31) of controls with known staging were diagnosed with early-stage disease (one-sided p=0.24). Relative risk was 1.21 (95% CI 0.75-1.95) 0.82 (95% CI 0.52-1.31) for early-stage or ad-vanced cancers, respectively. Overall sensitivity for sputum (in those randomised to surveillance) was low (40.5 with a cumulative false-positive rate (FPR) of 32.8%. 55% of cancers had normal sputum results throughout. Among sputum-positive individuals who had AF sensitivity was 45.5% and cumulative FPR was 39.5%; the corresponding measures for those who had LDCT were 100% and 16.1%, respectively.

CONCLUSIONS: Our sequential strategy, using sputum cytology/cytometry to select high-risk individuals for AFB and LDCT, did not lead to a clear stage shift did not improve the efficiency of lung cancer screen-ing.

Fazit:

Diese Studie konnte die Risikogruppe für ein mögliches Screening mit Low-dose-CT für das Lun-genkarzinom nicht weiter eingrenzen. Bisher empfehlen die deutschen und europäischen Fach-gesellschaften noch kein flächendeckendes Screening.
In einer großen amerikanischen Studie mit pos. Evidenz erscheint die absolute Risikoreduktion von 0,4% nicht wirklich beeindruckend und die hohe Rate an falsch pos. Befunden ist problematisch. Wir sollten eher bei Symptomen und Risikogruppen aufmerksam sein.

Fazit Regen:

Wir screenen eigentlich nicht. Wir schicken Patienten mit Symptomen mit Raucheranamnese noch zum Röntgen-Thorax, besser wäre ein Low-dose-CT.