TABLE 4.

Proliferative Pulmonary Lesions^a

Finding	Exposureb	Descriptorc	Inhalation + postinhalation periods (months)
			5 + 0	5 + 4	5 + 8	5 + 13	10 + 0	10 + 4	10 + 8	18 + 0
All proliferative findings	Sham	Multiplicity
		Mean	0.342	0.743	1.250	2.139	0.720	1.000	2.139	2.139
		SE	0.078	0.132	0.228	0.208	0.187	0.189	0.208	0.208
		Incidence (%)	34	54	75	97	48	65	97	97
		Number of mice	38	35	20	36	25	23	36	36
	MS-150	Multiplicity
		Mean	0.625	1.625	2.304	3.593	1.750	3.600	3.960	3.880
		SE	0.145	0.294	0.374	0.382	0.234	0.336	0.398	0.418
		Test		*		*	*	*	*	*
		Incidence (%)	50	75	91	96	86	100	100	96
		Number of mice	24	24	23	27	28	20	25	25
	MS-300	Multiplicity
		Mean	0.342	1.846	2.864	5.043	1.500	3.792	6.500	5.091
		SE	0.087	0.174	0.485	0.493	0.267	0.307	0.475	0.405
		Test		*	*	*#		*	*#	*#
		Incidence (%)	32	90	86	100	73	96	100	95
		Number of mice	38	39	22	23	26	24	26	22
Nodular hyperplasia	Sham	Multiplicity
		Mean	0.158	0.057	0.100	0.389	0.040	0.043	0.389	0.389
		SE	0.060	0.040	0.069	0.107	0.040	0.043	0.107	0.107
		Incidence (%)	16	6	10	31	4	4	31	31
	MS-150	Multiplicity
		Mean	0.458	0.583	0.130	0.148	0.321	0.350	0.120	0.240
		SE	0.134	0.146	0.072	0.088	0.116	0.109	0.066	0.105
		Test		*				*
		Incidence (%)	38	46	13	11	25	35	12	20
	MS-300	Multiplicity
		Mean	0.237	0.436	0.000	0.217	0.346	0.375	0.192	0.318
		SE	0.070	0.088	0.000	0.108	0.095	0.101	0.079	0.121
		Test		*				*
		Incidence (%)	24	41	0	17	35	38	19	27
Bronchioloalveolar adenoma	Sham	Multiplicity
		Mean	0.184	0.629	0.650	0.528	0.520	0.609	0.528	0.528
		SE	0.064	0.130	0.196	0.116	0.154	0.151	0.116	0.116
		Incidence (%)	18	46	45	42	40	48	42	42
	MS-150	Multiplicity
		Mean	0.167	0.958	1.174	1.444	1.250	2.600	1.640	2.080
		SE	0.078	0.213	0.215	0.241	0.222	0.343	0.215	0.310
		Test				*	*	*	*	*
		Incidence (%)	17	63	74	78	71	90	88	84
	MS-300	Multiplicity
		Mean	0.105	1.385	1.955	1.652	1.115	2.583	3.038	2.500
		SE	0.050	0.150	0.357	0.271	0.250	0.335	0.398	0.393
		Test		*	*	*		*	*#	*
		Incidence (%)	11	82	82	74	58	96	96	86
Bronchioloalveolar carcinoma	Sham	Multiplicity
		Mean	0.000	0.057	0.500	1.222	0.160	0.348	1.222	1.222
		SE	0.000	0.040	0.136	0.160	0.075	0.102	0.160	0.160
		Incidence (%)	0	6	45	78	16	8	78	78
	MS-150	Multiplicity
		Mean	0.000	0.083	1.000	2.000	0.179	0.650	2.200	1.560
		SE	0.000	0.058	0.199	0.354	0.090	0.196	0.351	0.283
		Test							*
		Incidence (%)	0	8	74	81	14	13	88	76
	MS-300	Multiplicity
		Mean	0.000	0.026	0.909	3.174	0.038	0.833	3.269	2.273
		SE	0.000	0.026	0.254	0.396	0.038	0.197	0.291	0.396
		Test				*#			*#	*
		Incidence (%)	0	3	55	100	4	20	100	77

Note. The sham-exposed mice for the 5 + 13, 10 + 8, and 18 + 0 months of exposure regimens are the same.

^aPooled analysis of findings in all lung lobes.

^bMS-150 and MS-300: MS at target concentrations of 150 and 300mg TPM/m3, respectively.

^cTest: Symbols * and # represent statistically significant difference to sham-exposed or MS-150–exposed mice, respectively.