- Sentinel lymph node biopsy (SLNB):
- Is the standard of care in patients with early stage:
- Clinically node negative breast cancer
- Is the standard of care in patients with early stage:
- Compared to axillary lymph node dissection (ALND):
- SLNB has lower morbidity, including:
- A lower risk of musculoskeletal limitations and lymphedema
- In general, SLNB can be performed with the use of:
- Blue dye
- Technetium-99 (99mTc)
- Dual agents
- SLNB has lower morbidity, including:
- The role of SLNB in pregnancy:
- Is not clearly defined:
- Updated American Society of Clinical Oncology (ASCO) Guidelines:
- Upholds its prior recommendation that SLNB should not be performed in pregnancy:
- The strength of the recommendation, however, is described by the ASCO expert panel to be “weak,” as it is based on ”informal consensus” rather than quality evidence
- Upholds its prior recommendation that SLNB should not be performed in pregnancy:
- Updated American Society of Clinical Oncology (ASCO) Guidelines:
- Several retrospective studies have described the safety of SLNB during pregnancy:
- The majority of patients in these studies underwent SLNB with 99mTc alone;
- However, methylene blue dye was used in some patients
- One recent retrospective review reported on 145 women with clinical node-negative disease who underwent SLNB during pregnancy:
- The mapping agents utilized were 99mTc alone (66%), methylene blue dye alone (9.7%), dual agents (10.3%), and the remainder was unknown
- Sentinel lymph nodes were identified in 99.3% of patients, with excellent gestational outcomes
- No neonatal adverse events related to the SLNB procedure were reported
- The majority of patients in these studies underwent SLNB with 99mTc alone;
- Is not clearly defined:
- Models of fetal radiation exposure:
- Have demonstrated that the use of 99mTc for SLNB:
- Leads to a negligible dose to the fetus of 0.014 mGy or less:
- Whereas risk of fetal malformation is associated with levels greater than 100 mGy
- Leads to a negligible dose to the fetus of 0.014 mGy or less:
- Lower doses of exposure can be achieved using a 1-day protocol rather than a 2-day protocol
- Have demonstrated that the use of 99mTc for SLNB:
- The use of lymphazurin dye:
- Is not recommended due to the 1% to 2% risk of anaphylaxis
- Historically, the use of direct intra-amniotic injection of methylene blue dye for identification of ruptured membranes led to significant neonatal complications:
- Recent pharmacokinetic data indicate that the absorption of methylene blue dye used during SLNB is minimal
- Although the use of methylene blue dye for SLNB has been described:
- The data are limited in comparison to that of 99mTc
- Thus, with respect to axillary staging:
- The risks and benefits of ALND vs. SLNB must be discussed with the patient prior to surgery
- References
- Giuliano AE, Kirgan DM, Guenther JM, Morton DL. Lymphatic mapping and sentinel lymphadenectomy for breast cancer. Ann Surg. 1994;220(3):391-398.
- Lyman GH, Somerfield MR, Bosserman LD, Perkins CL, Weaver DL, Giuliano AE. Sentinel lymph node biopsy for patients with early-stage breast cancer: American Society of Clinical Oncology Clinical Practice Guideline Update.J Clin Oncol.2017;35(5):561-564.
- Han SN, Amant F, Cardonick EH, et al. Axillary staging for breast cancer during pregnancy: feasibility and safety of sentinel lymph node biopsy. Breast Cancer Res Treat. 2018;168(2):551-557.
- Gropper AB, Calvillo KZ, Dominici L, et al. Sentinel lymph node biopsy in pregnant women with breast cancer. Ann Surg Oncol. 2014;21(8):2506-2511.
- Gentilini O, Cremonesi M, Toesca A et al. Sentinel lymph node biopsy in pregnant patients with breast cancer. Eur J Nucl Med Mol Imaging. 2010;37(1):78-83.
- Pandit-Taskar N, Dauer LT, Montgomery L et al. Organ and fetal absorbed dose estimates from 99mTc-sulfur colloid lymphoscintigraphy and sentinel node localization in breast cancer patients. J Nucl Med. 2006;47(7):1202-1208.
Rodrigo Arrangoiz MS, MD, FACS, FSSO 