Table 2.

Incidence of Lymphedema by Year and Cumulative Incidence of First Occurrence of Lymphedema by Age Group at Breast Cancer Diagnosis, by All Ages Combined, and Weighted to the Breast Cancer Population of Philadelphia and Delaware Counties During 1999 to 2001

Year	Age < 50 Years			Age 50-79 Years			Age 80+ Years			All Patients			Weighted‡ Cumulative Incidence
	No. of New Lymphedema Diagnoses	No. of Participants at Risk at Start of Year*	Cumulative Incidence†	No. of New Lymphedema Diagnoses	No. of Participants at Risk at Start of Year	Cumulative Incidence	No. of New Lymphedema Diagnoses	No. of Participants at Risk at Start of Year	Cumulative Incidence	No. of New Lymphedema Diagnoses	No. of Participants at Risk at Start of Year	Cumulative Incidence
Year 1	59	196	0.31	86	354	0.25	15	81	0.19	160	631	0.26	0.25
Year 2	12	124	0.38	16	253	0.30	3	61	0.23	31	440	0.31	0.30
Year 3	8	102	0.43	12	215	0.34	0	49	0.23	20	366	0.36	0.34
Year 4	6	82	0.47	11	171	0.38	0	29	0.23	17	282	0.40	0.38
Year 5	4	74	0.50	5	150	0.40	1	25	0.26	10	249	0.42	0.41

^*Denominators are reduced by loss to follow-up and by censoring at time of first lymphedema occurrence.

^†Cumulative incidence using standard survival analysis methods.

^‡Weighted by age distribution of breast cancer population of Philadelphia and Delaware Counties.