. 2010 Jun 10;37(11):2037–2047. doi: 10.1007/s00259-010-1505-2

Table 1.

Patient and primary tumour characteristics

			Second primary group (n = 16)		Metastatic disease group (n = 21)
Patient characteristics						p value
Mean age (range)			68 years (49–85 years)		67 years (47–84 years)	0.715
Sex (m:v)			11:5		12:9	0.471
Smoking status	Smoker		7		10	0.713
	Ex-smoker		7		9
	Non-smoker		2		1
	Missing		0		1
Mean no. of pack years			33.6 ± 15.9		35.0 ± 21.2	0.842
Conclusion^a based on	Histopathology		13		5
	P53 mutation analysis		1		0
	Immunohistochemistry		2		0
	Clinical features		0		16
Curability^b	Potentially curable		12		0
Curability^b	Incurable		4		21
Characteristics of primary tumours			Index tumour	Synchronous pulmonary tumour
Site	Lung		7	16	21
	Colorectum		5	0	0
	Head and neck		4	0	0
Histopathology	SCLC		0	0	3
	NSCLC	AC	9	9	13
		BAC	0	1	0
		SCC	7	2	1
		LCC	0	2	2
		Undifferentiated	0	0	2
	Other		0	2	0
Differentiation	Very poor		0	0	3
	Poor		6	8	7
	Intermediate		8	2	1
	Well		0	2	1
	Unspecified		2	4	9
Stage^c	IA		4	5	0
	IB		2	1	0
	IIA		2	2	0
	IIB		2	3	0
	IIIA		4	2	0
	IIIB		0	1	2
	IV		2	1	19
	Missing		0	1	0

SCLC small cell lung carcinoma, NSCLC non-small cell lung carcinoma, AC adenocarcinoma, BAC bronchioloalveolar carcinoma, SCC squamous cell carcinoma, LCC large cell carcinoma

^aThe conclusion second primary tumour or metastatic disease was based on histopathological or immunohistochemical features, TP53 mutation analysis results or clinical features. The latter included localization of multiple (more than two) malignancies in a pattern typical for metastatic spread of the identified primary tumour

^bPatients with two tumours of stage I–IIIA were considered potentially curable, whereas patients with at least one tumour staged IIIB/IV were considered incurable (TNM staging system version 6)

^cAccording to the sixth edition of the TNM classification for lung cancer developed by the International Association for the Study of Lung Cancer [42]