Table 3.

Effusion cytology and EGFR mutation status.

(A) By sediments
Cytology	EGFR mutation testing result						N
	Invalid		Mutation undetected		Mutation detected
Negative	1	2.9%	18	51.4%	16	45.7%	35	100.0%
Positive	1	1.4%	2	2.7%	70	95.9%	73	100.0%
	2	1.9%	20	18.5%	86	79.6%	108	100.0%
(B) By supernatants
Cytology	EGFR mutation testing result						N
	Invalid		Mutation undetected		Mutation detected
Negative	3	8.6%	11	31.4%	21	60.0%	35	100.0%
Positive	5	6.8%	5	6.8%	63	86.3%	73	100.0%
	8	7.4%	16	14.8%	84	77.8%	108	100.0%