Significance of internal mammary lymph nodes in patients after mastectomy with tissue-expander reconstruction: a case-control study

Aim: To retrospectively assess the frequency of internal mammary lymph nodes (IMNs) in patients after mastectomy and tissue-expander reconstruction. Materials and methods: Statistical analysis was performed for all available data in patients with mastectomy and tissue-expander reconstruction from 2004-2007 (study group). The data were compared with that of a control population with mastectomy who did not have reconstruction (control group). Patients with recurrent breast cancers, previous breast reconstruction, surgeries performed at outside hospitals, no available pre- or postoperative computed tomography (CT) or magnetic resonance imaging (MRI) data, or inadequate imaging follow-up were excluded. Results: There were eight patients in the study group (median age 50.5 years, seven breast cancers), and eight patients in the control group (median age 52 years, seven breast cancers). No patients had IMNs on their preoperative imaging examinations. New IMNs were present in postoperative imaging in seven of eight patients (7/8, 87.5%) in the study group. All of them were stable or decreased in size on subsequent imaging examinations. None of the patients in the control group had IMNs (0/8). Conclusion: IMNs are common on imaging after mastectomy and tissue-expander placement. The IMNs decreased or remained stable on follow-up imaging and may represent reactive nodes.