ObjectiveTo evaluate the effects of sentinel lymph node biopsy following total mastectomy on immunologic function and prognosis for patients with early breast cancer. MethodsTwo hundred and eleven patients with early breast cancer were entered in this study. In all these cases, the results of sentinel lymph node biopsy were negative. These patients were randomly divided into control group and research group. In 86 cases of control group, the sentinel lymph node biopsy and axillary lymph node dissection following total mastectomy was performed. In 125 cases of research group, the sentinel lymph node biopsy following total mastectomy was performed. The injury of shoulder joint function was analyzed in one year after surgery. The changes of T cell subsets and IL-2 level were detected in the patients respectively on the first day before operation, the second week after operation, and the fourth week after operation. Postoperative fatality rate and postoperative recurrence rate were also observed in two groups. Results①The points of shoulder joint function in the control group and the research group were 72.7±6.5 and 93.5±8.2 respectively, there was an obvious difference (P < 0.05).②The injury degree of shoulder joint function in the research group was significantly lower than that in the control group (P < 0.01).③Compared with the control group, the changes of T cell subsets and the IL-2 level had no significant differences in the research group on day 1 before operation and on week 2 after operation (P > 0.05). On the fourth week after surgery, the CD4+, CD4+/CD8+, and IL-2 level in the research group were obviously higher than those in the control group (P < 0.05). However, the percentage of CD8+ T cell in the research group was significantly lower than that in the control group (P < 0.05).④There were no significant differences for postoperative fatality rate and postoperative recurrence rate between two groups (P > 0.05). ConclusionsSentinel lymph node biopsy for patients with early breast cancer is safe and reliable. With respect to conventional axillary lymph node dissection, it could improve immune function and quality of life after surgery in patients with early breast cancer.