Results of three-year mass screening programme for lung cancer using mobile low-dose spiral computed tomography scanner

Abstract

SummaryThe aim of this study was to evaluate the usefulness of annual screening for lung cancer by low-dose computed tomography (CT) and the characteristics of identified lung cancers. Subjects consisted of 5483 general population aged 40-74 years, who received initial CT scans in 1996, followed by repeat annual scans for most subjects in 1997 and 1998, with a total of 13 786 scans taken during 1996-1998. Work-up examinations for patients with suspicious lesions were conducted using diagnostic CTs. The initial screening in 1996 detected suspicious nodules in 279 (5.1%) of 5483 subjects, and 22 (8%) were confirmed surgically to have lung cancer. Corresponding figures in 1997 and 1998 screening studies were 173 (3.9%) of 4425 and 25 (14%) of 173, and 136 (3.5%) of 3878 and 9 (7%) of 136, respectively. The sensitivity and specificity of detecting surgically confirmed lung cancer were 55% (22/40) and 95% (4960/5199) in 1996 and 83% (25/30) and 97% (4113/4252) in 1997 screening, respectively. 88% (55/60) of lung cancers identified on screening and surgically confirmed were AJCC stage IA. Our trial allowed detection of nearly 11 times the expected annual number of early lung cancers. Repeat CT allowed the detection of more aggressive, rapidly growing lung cancers, compared to those in the initial screening. 25-32 © 2001 Cancer Research Campaign doi: 10.1054/ bjoc.2000.1531 available online at http://www.idealibrary.com on http://www.bjcancer.com to 150 detected SSPNs from these screenees. A much larger series of SSPN is required to study the second question, the prevalence of malignancy among the detected SSPNs, by getting an appreciable number of malignant SSPN, because the prevalence of malignant SSPN among high-risk population is estimated to be of the order of 1%. We defined our sample size of 5000 to 10 000, which was fairly larger than that indicated by Henschke et al, because we aimed to conduct our trial of CT screening for lung cancer using CT among the general population, which included never-smoked inhabitants in this rural area in Japan. In our study, inhabitants of 29 local municipalities in the Nagano Prefecture, Japan, who were 40 years of age or older were specifically requested in 1996 to volunteer for this programme. The annual mortality rate due to lung cancer in the same region was 37.3 per 100 000 population in 1998. Therefore, it was expected in our trial at least nearly 100 SSPNs be detected at each annual screening to undergo work-up examination, which would permit us to estimate the probability of CT-detected SSPN. Although we expected to encounter at least several cases with lung cancer among the total 5000 to 10 000 participants, we were not sure about the expected number of cancer cases because no information on this aspect was available. All subjects gave informed consent to receive base line and annual repeat CT scans of the thorax. SubjectsThe material of this study comprised a total of 13 786 CT examinations, including 5483 initial CT scans in 1996, 4425 first-year repeat CT scans in...

Lung Cancer Screening with CT

“…As if to confirm this premise, the most compelling evidence for overdiagnosis from the current screening studies is the observation of roughly equivalent rates of lung cancer among smokers and non-smokers in Japanese population CT screening, where lung cancer detection rates with CT in non-smoking females exceed annual mortality rates by several fold (11). Some proportion of these excess screen-detected cancers are tumors that would never contribute to the death of the individual.…”

Integrated multislice CT and Tc–99m Sestamibi SPECT–CT evaluation of solitary pulmonary nodules

“…In passato, esami diagnostici basati sulla radiografia standard del torace e sull'esame citologico dell'escreato non hanno dato i risultati sperati nella riduzione della mortalità [11][12][13]. Negli ultimi anni si sta assistendo ad una profonda revisione del concetto di diagnosi precoce del cancro del polmone grazie agli incoraggianti risultati ottenuti con la tomografia computerizzata multistrato [8,14,15], ed a tecniche complementari di medicina nucleare. Un NPS è definito come una opacità rotondeggiante intraparenchimale moderatamente ben delimitata con diametro massimo inferiore a 3 cm [1].…”

“…Over the last few years, the concept of early diagnosis of lung cancer has been reconsidered as a following the encouraging results obtained with multidetector computed tomography (MDCT) [8,14,15] and the use complementary nuclear medicine methods. A solitary pulmonary nodule is defined as a rounded intraparenchymal opacity that is moderately well delimited, with a maximum diameter less than 3 cm [1].…”

Curative Wedge Resection for Non-Invasive Bronchioloalveolar Carcinoma

“…Recently thoracic CT screening for the detection of early lung cancer is regarded as a possible tool to decrease lung cancer mortality (Henshke 2000; Kaneko et al 2000;Sone et al 2001). Small size pulmonary adenocarcinomas can be detected with CT screening.…”

“…Many lung cancers with ground glass opacity (GGO), a faint homogeneous shadow with sharp margin, are detected by thoracic computed tomography (CT) scans (Henshke 2000; Kaneko et al 2000;Sone et al 2001). Some of them are pure bronchioloalveolar carcinoma (BAC) without any stromal, vascular or pleural invasion (Noguchi et al 1995;Sakurai et al 2004).…”