Introduction: Although the status of the regional lymph nodes is an important determinant of prognosis in breast cancer, harvesting sentinel nodes (SN) detected in the internal mammary chain (IMC) is still controversial. Aims: To determine in how many patients a positive IMC-SN might change the systemic or locoregional adjuvant therapy, with a possible benefit in outcome. Patients and methods: During 6 frac(1, 2)years data of T1-2 breast cancer patients, having an SN procedure, were prospectively collected. Our policy was not to explore the IMC even if it was the only localization of an SN. Results: In 86 of 571 patients lymphoscintigraphy showed an IMC-SN. In 64 of these, the axillary SN was negative and only 25 of these patients did not have an indication for adjuvant systemic treatment based on their tumor characteristics. In the literature, IMC metastases are found in 0-10% of axillary negative patients. Routine IMC-SN biopsies would have resulted in an indication for adjuvant systemic therapy in 2-3 of our patients. Four parasternal recurrences were found during a median follow-up of 51 months. Conclusions: Harvesting IMC-SNs is a procedure of which only a limited number of patients have therapeutical benefit. Even with a thorough selection of patients, the extra morbidity of the procedure should be weighed against the potential benefit for the patient.