Abstract P3-14-06: A single-center report of 125 cases of incidental internal mammary lymph node biopsy in free abdominal flap breast reconstruction
Authors: Quan C , Huang N , Yang B , Zhang Y , Huang X , Chen J , Wu J 
Published: March 2017

Abstract
Objective
The aim of the current study is to determine the clinical value of incidental internal mammary lymph node biopsy in free abdominal flap breast reconstruction using internal mammary as recipient vessels and to investigate the risk factors of internal mammary lymph nodes metastasis.
Methods
The clinical data of all free abdominal flap breast reconstructions using internal mammary as recipient vessels performed from November 2006 to April 2016 in Department of Breast Surgery, Fudan University Shanghai Cancer Center were included into the study. The incidence of internal mammary lymph node biopsy and the rate of metastasis were described. The differences between groups were compared using χ2 test. Univariate and multivariate Logistic regression analysis was conducted to evaluate risk factors of internal mammary lymph node metastasis.
Results
A total of 125 patients met the inclusion criteria, 89 (71.2%) of whom adopted unilateral immediate breast reconstructions. 64.8% of them were diagnosed with primary invasive breast cancer, while 27.2% were carcinoma in situ. According to AJCC TNM staging system, the percentages of patients with stage 0, I, II, III were 27.2%, 26.4%, 27.2% and 8.0%.
62 (49.6%) patients had internal mammary lymph nodes harvested. 6.4% (4/62) of those who adopted internal mammary lymph nodes biopsies were diagnosed with internal mammary lymph nodes metastasis, all in immediate breast reconstructions. 72 (57.6%) patients cut off costicartilage (the second or third costicartilage) during the exposure of internal mammary vessels. The excision of costicartilage is not associated with the harvest rate of internal mammary lymph node (P&gt;0.05). All of the 4 patients upstaged their TMN stage of tumor after internal mammary lymph node metastasis and adopted adjuvant chemotherapy and radiotherapy. Up to May 2016, no recurrence or distant metastasis was reported.
In Logistic regression analysis, larger invasive tumor size and axillary lymph node metastasis were found to have correlations with internal mammary lymph node metastasis (larger invasive tumor size: P=0.029; axillary lymph node metastasis: P=0.004), while tumor location or immunohistochemical subtype had no correlations. In addition, axillary lymph node metastasis was proved to be a independent risk factor of internal mammary lymph node metastasis (P=0.036) while tumor size was not.
Conclusions
Internal mammary lymph nodes found incidentally during internal mammary recipient vessel exposure for free flap breast reconstruction could provide surgeons with important information for further treatment. This approach for internal mammary lymph node biopsy revealed an appreciable success rate and should be promoted in clinical practice. The size of invasive tumor and the axillary lymph node metastasis were associated with internal mammary lymph node metastasis.Objective
The aim of the current study is to determine the clinical value of incidental internal mammary lymph node biopsy in free abdominal flap breast reconstruction using internal mammary as recipient vessels and to investigate the risk factors of internal mammary lymph nodes metastasis.
Methods
The clinical data of all free abdominal flap breast reconstructions using internal mammary as recipient vessels performed from November 2006 to April 2016 in Department of Breast Surgery, Fudan University Shanghai Cancer Center were included into the study. The incidence of internal mammary lymph node biopsy and the rate of metastasis were described. The differences between groups were compared using χ2 test. Univariate and multivariate Logistic regression analysis was conducted to evaluate risk factors of internal mammary lymph node metastasis.
Results
A total of 125 patients met the inclusion criteria, 89 (71.2%) of whom adopted unilateral immediate breast reconstructions. 64.8% of them were diagnosed with primary invasive breast cancer, while 27.2% were carcinoma in situ. According to AJCC TNM staging system, the percentages of patients with stage 0, I, II, III were 27.2%, 26.4%, 27.2% and 8.0%.
62 (49.6%) patients had internal mammary lymph nodes harvested. 6.4% (4/62) of those who adopted internal mammary lymph nodes biopsies were diagnosed with internal mammary lymph nodes metastasis, all in immediate breast reconstructions. 72 (57.6%) patients cut off costicartilage (the second or third costicartilage) during the exposure of internal mammary vessels. The excision of costicartilage is not associated with the harvest rate of internal mammary lymph node (P&gt;0.05). All of the 4 patients upstaged their TMN stage of tumor after internal mammary lymph node metastasis and adopted adjuvant chemotherapy and radiotherapy. Up to May 2016, no recurrence or distant metastasis was reported.
In Logistic regression analysis, larger invasive tumor size and axillary lymph node metastasis were found to have correlations with internal mammary lymph node metastasis (larger invasive tumor size: P=0.029; axillary lymph node metastasis: P=0.004), while tumor location or immunohistochemical subtype had no correlations. In addition, axillary lymph node metastasis was proved to be a independent risk factor of internal mammary lymph node metastasis (P=0.036) while tumor size was not.
Conclusions
Internal mammary lymph nodes found incidentally during internal mammary recipient vessel exposure for free flap breast reconstruction could provide surgeons with important information for further treatment. This approach for internal mammary lymph node biopsy revealed an appreciable success rate and should be promoted in clinical practice. The size of invasive tumor and the axillary lymph node metastasis were associated with internal mammary lymph node metastasis.
Citation Format: Quan C, Huang N, Yang B, Zhang Y, Huang X, Chen J, Wu J. A single-center report of 125 cases of incidental internal mammary lymph node biopsy in free abdominal flap breast reconstruction [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P3-14-06.