Effect of Central Nervous System Metastases on Treatment Discontinuation and Survival in Older Women Receiving Trastuzumab for Metastatic Breast Cancer

Table 2

Incidence rates for metastases by site.

Site of metastasis	Number starting trastuzumab without indicated metastasis	Number developing indicated metastasis	Incidence rate (95% CI)
CNS	562	125	14.1 (11.9–16.9)
Bone	293	101	24.1 (19.8–29.3)
Liver	390	86	13.5 (11.0–16.7)
Lung/Chest	378	82	14.7 (11.8–18.2)
All Other	400	68	10.7 (8.5–13.6)

Note: Rates estimated over all follow-up time and reported per 1,000 person-months of follow-up.