Table 1.

Major genetic characteristics of small (SCLC) and non-small cell (NSCLC) lung cancers.

	SCLC	NSCLC
frequency in lung cancer patients	20%	80%
neuroendocrine properties	100%	rare
FHIT deletion/mutations	80%	40%
p53 deletion/mutations	85%	50%
p16 deletion/mutations	rare	60%
Rb deletion/mutations	90%	20%
LKB1 mutations	rare	30%
PTEN mutations	15–20%	infrequent
E-cadherin loss	?	10%
K-Ras activating mutations	rare	20%
c-myc overexpression	20%	rare
EGFR1 overexpression	rare	60%
HER2/Neu overexpression	rare	20%
Bcl-2 overexpression	85%	20%
autocrine loop	GRP-GRP receptor, SCF-Kit	HGF-Met, TGF-α
PI3K activation	+	+
microsatellite instability	35%	20%
telomerase activity	100%	80%
frequent allelic loss	4p, 4q, 5q, 8p, 10q, 13q, 17p, 22q	6q, 8p, 9p, 13p, 17p, 19q
3p deletion	100%	80%
3q amplification	+	+