From:  Redefining axillary management by selecting patients for omission of sentinel lymph node surgery in early breast cancer

 The main differences between the trials relate to selection criteria.

ParameterSOUNDINSEMABOOG 2013-08
Study designRandomized
Non-inferiority
Randomized
Non-inferiority
Randomized
Non-inferiority
Patients analyzed1,405 (ITT)4,858 (PP)1,572 (PP)
Tumor size ≤ 2 cm ≤ 5 cm≤ 5 cm
cT1 (≤ 2 cm) 100%80%83%
cT2 (2–5 cm)0%20%17%
Clinical nodal requirementcN0cN0cN0
Axillary imaging requirementMandatory negative ultrasound; biopsy if suspiciousPer institutional standardPer national standard
Median age60 years62 years61.5 years
HR+/HER2−87.8%95.2%86.8%
HER2-positive6.8%3.6%7.4%
Triple-negative5.4%1.2%5.8%
Grade 1–280%85–90%82%
Surgical backboneBCS + WBRTBCS + WBRTBCS + WBRT

SOUND: Sentinel node vs. Observation after axillary UltraSouND; INSEMA: INtergroup SEntinel MAmma trial; BOOG: Dutch Breast Cancer Research Group (BOrstkanker Onderzoek Groep); ITT: intention-to-treat protocol; PP: per-protocol; HER2: human epidermal growth factor receptor 2; HR: hormone receptor; BCS: breast conservative surgery; WBRT: whole-breast radiotherapy.