Adjuvant Chemotherapy After Lobectomy for T1-2N0 XXXX : Are the Guidelines Supported?

@entity5 @entity1 @entity1149
BACKGROUND: Evidence guiding adjuvant chemotherapy (AC) use after lobectomy for stage I @entity1149 ( @entity1149 ) is limited. This study evaluated the impact of AC use and @entity5 size on outcomes using a large, nationwide @entity5 database. METHODS: The effect of AC on long-term survival among @entity1 who underwent lobectomy for margin-negative pathologic T1-2N0M0 @entity1149 in the National Cancer Data Base from 2003 to 2006 was estimated using the Kaplan-Meier method. The specific @entity5 size threshold at which AC began providing benefit was estimated with multivariable Cox proportional hazards modeling. RESULTS: Overall 3,496 of 34,360 @entity1 (10.2%) who met inclusion criteria were treated with AC, although AC use increased over time from 2003, when only 2.7% of @entity1 with @entity5 less than 4 cm and 6.2% of @entity1 with @entity5 of 4 cm or larger received AC. In unadjusted survival analysis, AC was associated with a significant 5-year survival benefit for @entity1 with @entity5 less than 4 cm (74.3% vs 66.9%; P<.0001) and 4 cm or greater (64.8% vs 49.8%; P<.0001). In subanalyses of @entity1 grouped by strata of 0.5-cm increments in @entity5 size, AC was associated with a survival advantage for @entity5 sizes ranging from 3.0 to 8.5 cm. CONCLUSIONS: Use of AC among @entity1 with stage I @entity1149 has increased over time but remains uncommon. The results of this study support current treatment guidelines that recommend AC use after lobectomy for stage I @entity1149 larger than 4 cm. These results also suggest that AC use is associated with superior survival for @entity1 with @entity5 ranging from 3.0 to 8.5 cm in diameter.
