Incidental pulmonary nodules may lead to a high proportion of early-stage lung cancer: but it requires more than a high CT volume to achieve this

Figures & data

Figure 1. a. Increase in chest CT in Denmark between 2011 and 2021. b. Increase in proportion of stage I-II in Denmark between 2011 and 2021 para. c. Development in proportion of stages IA to IIB among Danish patients diagnosed with lung cancer between 2015 and 2021.

Figure 2. a. Proportion of stage IA lung cancer in Danish regions 2021. b. Correlation between proportion of stage IA lung cancer and chest CT per 1,000 inhabitants. c. All-cause survival rates of Danish lung cancer patients across all stages from 2016–2021.

Kaplan–Meier survival estimates

Table 1. Audit of stage IV lung cancer: follow-up of nodules.

Hospital	Patients reviewed	Percentage with CT within 2 years before diagnosis	Nodule described on CT	Percentage nodules with follow-up	Nodules likely progressed to stage IV lung cancer
Region North
Aalborg	736	11%	27	30%	23
Central Denmark Region
Aarhus	571	16%	45	89%	45
Gødstrup	365	22%	34	59%	31
Region of Southern Denmark
Vejle	695	15%	42	67%	36
Odense	427	18%	27	67%	26
Region Zealand
Roskilde	610	8%	21	76%	16
Næstved	662	11%	49	55%	33
All sites	4066	14%	245	64%	210

Table 2. Audit of stage IV lung cancer: missed nodules.

Hospital	Nodules not mentioned in CT report	Nodule seen at review that progressed to stage IV lung cancer	Percentage CT scans with undescribed nodules progressing to stage IV lung cancer
Region North
Aalborg	54	9	17%
Central Denmark Region
Aarhus	48	9	19%
Gødstrup	48	4	8%
Region of Southern Denmark
Vejle	60	10	17%
Odense	49	2	4%
Region Zealand
Roskilde	27	3	11%
Næstved	21	5	24%
All sites	307	42	14%

Data availability statement

Data on CT examinations and lung cancer stage distribution are publicly available. Anonymized data from the clinical auditing will be made available at reasonable request and after acceptance of the hospital directors.