Unenhanced Chest Computerized Tomography Assisted Sentinel Lymph Node Biopsy Could be a Highly Reliable Option for Only Methylene Blue Available Breast Cancer Patients

Special Article – Breast Cancer Surgery

Austin J Surg. 2018; 5(6): 1144.

Unenhanced Chest Computerized Tomography Assisted Sentinel Lymph Node Biopsy Could be a Highly Reliable Option for Only Methylene Blue Available Breast Cancer Patients

Wei H1*, Yao M1, Ba X2 and Fu P1

1Department of Breast Center, Zhejiang University School of Medicine, China

2Department of Pathology, Zhejiang University School of Medicine, China

*Corresponding author: Haiyan Wei, Breast Center, the Fist Affiliated Hospital, Zhejiang University School of Medicine, No. 79 Qing churns Road, Hangzhou, Zhejiang Province, China

Received: April 02, 2018; Accepted: April 24, 2018; Published: May 01, 2018


Background: Blue dye and radioisotope (RI) combined SLNB is the “best” protocol. However, RI is not available worldwide. This study is to evaluate the feasibility of unenhanced chest Computerized Tomography (CT) with three criteria for suspicious nodal metastasis assisted SLNB using only methylene blue (MB) as an alternative reliable option.

Patients and Methods: A total of 1771 consecutive patients with clinically node negative breast cancer were enrolled. For limiting FNR and surgical complications, the number of removed Sentinel Lymph Nodes (SLNs) was suggested to be 3~5. Unenhanced chest CT is mandatory to locate SLNs, which were graded from 1 to 3 according to suspicious criteria for metastasis. Three doctors adopted three SLNB methods. Periareolar sub-dermal injection using 4ml of 0.5% MB alone or in combination with a radioisotope was individually employed by two doctors. The third doctor used 2ml of 1% MB to inject into parenchyma to map SLNs.

Results: Both FNR and outcomes of patients showed no difference between three methods. We also confirmed that Lymph Vascular Invasion (LVI) and CT grade were both significantly correlated with SLN status (coefficients were0.68 and 0.25, p<0.001). Although there was no difference found in complications, but parenchymal injection did never cause skin necrosis.

Conclusion: Unenhanced chest CT could be are liable assistance to improve SLNB using only MB via parenchymal injection. This technique might be the safest and convenient option for SLNB in the study and RI could be safely spared.

Keywords: Breast cancer; Sentinel lymph node biopsy; Methylene blue; Computerized tomography


Chinese incidence of breast cancer has increased remarkably with the socioeconomic development, particularly in eastern coastal areas, and it has been expected to approach more than 100 cases per 100000 women aged 55~69 years by 2021 [1,2]. Whereas, benefitting from systemic therapy, the invasiveness of surgical treatment has been largely controlled. Clinical trials have revolutionized the pattern of clinical practice. Mastectomy and Auxiliary Lymph Node Dissection (ALND) were both profoundly proven not to improve survival and Quality of Life (QOL) when comparing with Breast-Conserving Therapy (BCT) and Sentinel Lymph Node Biopsy (SLNB) [3,4].

National Surgical Adjuvant Breast and Bowel Project (NSABP) B-32 and other trials identified that SLNB could not only reduce the surgical morbidities, but could also be reliable for auxiliary staging of clinically lymph node negative (cN0) breast cancer [5,6]. SNB has become the standard of care in patients with cN0 disease. Although blue dye and radioisotope (RI) combined lymphatic mapping was well established as a standard procedure to limit FNR [7-9], but the optimal protocol for SLNB is still under investigation. In many Japanese hospitals, due to the lack of RI, contrast enhanced CT lymphography (CT-LG) has been routinely used to stage the axilla accurately with dye-only SLNB [10]. It was concluded that using the only size criterion by CT-LG or MRI alone to diagnose SLNs was not sufficient. No matter what contrast regimen used, the cost and procedure of the technique they used were not practical in China.

Based on previous studies on ultra sonography and CT-LG, metastatic nodes have several abnormal signs [11,12]. In our daily wok, US-guided Core Needle Biopsy (CNB) and unenhanced chest CT have routinely been preoperatively adopted to evaluate node status and triage the patients. Because of unavailable RI and limited financial support in our country, most of patients, especially who live in remote rural areas, must receive more unnecessary ALND. In this context, we conduct this research to evaluate an unenhanced chest CT assisted method for SLNB and provide an alternative option for the given population.

Patients and Methods

Patientsrsquo; characteristics

From February 2007 to October 2015, a total of 1771cases of breast cancer patients were involved in this study. They ranged in age from 25 to 93 (median, 59). Their tumor size was ranged from 0.5 to 10cm. The 10cm tumor was identified as pure mutinous carcinoma in the left breast of an 83-year old lady. All patients were diagnosed by Fine Needle Aspiration (FNA) or Core Needle Biopsy (CNB) before surgery. Patients who were arranged to neoadjuvant chemotherapy including those diagnosed with inflammatory breast cancer and pregnant patients were excluded. When auxiliary lymph node was highly suspicious for metastasis, ultrasound (US)-guided CNB was introduced. When metastasis was not considered in the node on palpation or US, cN0 was identified and SLNB was applied. At the initial stage of SLNB, 190 patients consented to SLNB followed by level I/II ALND. Three SLNB techniques were employed individually by three surgeons. Thereafter, 1581patients consented to SLNB followed by ALND only if any metastasis was found in Sentinel Nodes (SNs) except for Isolated Tumor Cells (ITC). Level III clearance is performed unless metastasis occurred in nodes at level II [13]. Lymph Vascular Invasion (LVI) was widely found to be significantly correlated with node status [14,15], therefore it was evaluated as well and classified as three levels. The first level was defined as absence of LVI and the second and third levels were defined as focal and diffused LVI, respectively. This retrospective research was approved by the Ethics Committee of the First Affiliated Hospital, Zhejiang University School of Medicine according to the revised version of Declaration of Helsinki and its amendments in 1983, 1989, and 1996 [16]. Patients have signed informed consent for publication of their clinical data.

SLNB protocols

After cN0 breast cancer was confirmed, unenhanced chest CT with 3mm slice thickness was routinely performed and assessed by two imaging experts. According to their experience and previous study [11], three abnormal signs for suspicious nodes on CT were identified. Firstly, it is cortical thickening and diminished or absent hilum. Secondly, a height/width ratio is close to 1 on the twodimensional slice of a coronal scan across the hilum of the node. Thirdly, the maximum diameter of the node is no less than 1cm [12]. When the node meets one or more criteria, it was supposed to be suspicious or typical metastatic SLNs and marked on the skin (Figure 1, Figure 2a). During operation, SLNs could easily be localized by the size, numbers and the predicted anatomical position [17].