Key Words: Breast cancer--Axillary dissection--Survival. Breast cancer is the most ... Paget's disease; and 1 patient who had a positive lymph node. All analyses ...
Annals of Surgical Oncology, 5(2): 140-149 PuNished by Lippincott-Raven Publishers © 1998 The Society of Surgical Oncology, inc.
Association Between Extent of Axillary Lymph Node Dissection and Survival in Patients With Stage I Breast Cancer Julie Ann Sosa, MD, Marie Diener-West, PhD, Yuriy Gusev, PhD, Michael A. Choti, MD, Julie R. Lange, MD, William C. Dooley, MD, and Martha A. Zeiger, MD
Background: The role of axillary lymph node dissection for stage I (T1N0) breast cancer remains controversial because patients can receive adjuvant chemotherapy regardless of their nodal status and because its therapeutic benefit is in question. The purpose of this study was to determine whether extent of axillary dissection in patients with T1N0 disease is associated with survival. Methods: Data from 464 patients with T1N0 breast cancer who underwent axillary dissection from 1973 to 1994 were examined retrospectively. Kaplan-Meier estimates of overall survival, disease-free survival, and recurrence were calculated for patients according to the number of lymph nodes removed (10; 15), and survival curves compared using the WilcoxonGehan statistic. Cox proportional hazards regression modelling was used to adjust for confounding prognostic variables. Results: Median follow-up time was 6.4 years. Patient groups were similar in age, menopausal status, tumor size, hormonal receptor status, type of surgery, and adjuvant therapy. There was a statistically significant improvement in disease-free survival in the i> 10 versus :
FIG. 5. Kaplan-Meier estimates of disease-free survival, comparing patients who had fewer than 15 axillary lymph nodes removed (15 LN).
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0.25
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5 10 T i m e f r o m S u r g e r y in Y e a r s
Ann Surg Oncol, Vol. 5, No. 2, 1998
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EXTENT OF A X I L L A R Y DISSECTION
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TABLE 5. Cox proportional hazards regression model: LNIO nodal grouping ~ Overall survival
Disease-flee survival
Predictor variable b
Hazard ratio
95% CI
Hazard ratio
95% CI
LN10 Recurrence PRAdjuvant therapy: Chemotherapy Hormonal therapy Radiation therapy Combination 1973-1984
1.40 5.45*
.89, 2.20 3.29, 9.02
1.66 C
1.10, 2.52
3.64 ~ 2.86 d
1.73 C
1.75, 7.57 1.32, 6.17
1.10, 2.72
Recurrence Hazard ratio
95% CI
3.51 c
1.29, 9.60
3.03 c
1.01, 9.06
16.1U
3.84, 67.61
5.12 c 27.87" 5.00 a
1.06, 24.77 6.32, 122.80 1.57, 15.75
Those hazards ratios that were not statistically significant are not reported. b Reported hazards ratio represents increased risk for the level of the predictor variable shown in the table compared to the other level of the covariate. c p ~< .05. d p ~ .01. e p ~ .001. a
Our study suggests that for patients with invasive primary breast tumors smaller than 2 cm in diameter, the performance of a more extensive axillary dissection as part of the surgical procedure is independently associated with an increase in both disease-free and overall survival at 5 and 10 years. The fact that there also appears to be a reduction in the rate of recurrence implies that there may be an associated decrease in breast cancer-specific mortality. A smaller proportion of the recurrences were locoregional in the ~>10 compared to the
