Sentinel Lymph Node Biopsy in Breast Cancer
Ellen Schlichting, Marianne Efskind Harr, Torill Sauer, Almira Babovic, Rolf Kåresen
BackgroundSentinel lymph node (SN) biopsy is a highly accurate technique for identifying axillary metastases from a primary breast carcinoma.
Material and methodsBetween 2000 and 2005, SN biopsy was performed in 1409 patients with breast carcinoma or ductal carcinoma in situ grade 3. Peritumoral radiocolloid (60-80 MBq 99 Tc-Nanocoll) was injected the day before operation and blue dye was injected around the tumor peroperatively.
ResultsSN was detected in 90,2% of the operations. Training of the individual surgeon influenced the detection rate. Metastases to SN were detected in 25% of the patients. Of the 319 patients with a positive SN, 51,7% had no further positive nodes in the axilla. Patients with a tumor less than 20 mm had metastases in 21,6% of the SN, while tumors larger than 20 mm were positive in 31,8% of the patients. Age below 50 years was associated with a positive SN in 35,3%, while age above 50 years reduced the incidence of positive SN to 21,9%. Mean age was 58 years. The mean tumor size was 16,6 mm. Tumors were located in the upper, outer quadrant in 59%. There were three patients with local recurrence in the axilla early in the series. Ductal carcinoma in situ grade 3 was diagnosed preoperatively in 109 patients (cytology), 88 had this diagnosis after histology (the rest had combinations with cancer or in situ lesions with another grade). Axillary metastases were found in 4.8% of these patients. Two out of 19 patients had metastases to parasternal SN.
InterpretationSN biopsy has a proven valid in the staging of the axilla in patients with breast cancer and have replaced routine axillary clearance. The method should also be considered in patients with high-grade DCIS.