An evaluation of incidental metastases to internal mammary lymph nodes detected during microvascular abdominal free flap breast reconstruction.

Background: The significance of internal mammary lymph nodes (IMLNs) encountered during dissection of internal mammary vessels (IMVs) for microvascular free flap breast reconstruction (FFBR) remains uncertain. We report our experience with the opportunistic harvest of IMLNs during FFBR. Therapeutic implications and patient outcomes are explored.

Methods: All IMV anastomoses for delayed (DBR) or immediate breast reconstruction (IBR), between 1997 and 2009 were recorded. Opportunistic IMLN harvests were identified and patient characteristics and outcomes recorded from review of case records.

Results: Of the 293 FFBRs, 43 patients had 46 IMLNs harvested during 20 immediate and 26 delayed FFBRs. Six patients had positive nodes (4 IBR and 2 DBR), and were offered post operative chemotherapy. Four received radiotherapy to the internal mammary chain. Three of the four IMLN+ve IBR patients have died of metastatic disease at 23, 33 and 55 months after reconstruction. The two IMLN+ve DBR patients were alive at 4 and 20 months.

Discussion And Conclusion: Although routine biopsy of IMLNs for staging in breast cancer is not standard practice, if identified during IMV recipient site preparation for microvascular anastomosis, opportunistic biopsy should be performed due to the additional staging information provided and subsequent effect upon the predicted prognosis.