Sentinel node involvement with or without completion axillary lymph node dissection: treatment and pathologic results...

Area of Science:

• Oncology
• Surgical Oncology
• Clinical Trials

Background:

• Completion axillary lymph node dissection (cALND) is frequently omitted for breast cancer patients with limited sentinel node (SN) metastases.
• Previous trials had limitations, excluding patients with SN macro-metastases and total mastectomy or more than two involved SNs.

Purpose of the Study:

• To analyze treatment and pathologic outcomes in patients undergoing cALND versus SNB alone within the SERC trial.
• To evaluate the safety and efficacy of omitting cALND in a broader patient population, including those with SN macro-metastases.

Main Methods:

• The SERC trial was a multicenter, randomized, non-inferiority phase-3 trial comparing cALND with SNB alone.
• 1855 patients with cT0-1-2, cN0 breast cancer and SN involvement (ITC, micro-, or macro-metastases) were randomized.
• Patients could have undergone mastectomy or breast-conserving surgery, with or without adjuvant chemotherapy (AC).

Main Results:

• No significant differences in patient/tumor characteristics, surgery type, or AC use were observed between the cALND and SNB alone arms.
• Rates of SN involvement by ITC, micro-metastases, and macro-metastases were 5.91%, 28.12%, and 65.97%, respectively, with no significant inter-arm differences.
• Multivariate analysis identified no AC after ALND and >2 involved SNs as factors associated with a higher positive non-SN rate. Higher positive-NSN rates were seen with AC after ALND compared to before.

Conclusions:

• Omitting cALND in favor of SNB alone is a safe option for a broad range of breast cancer patients, including those with SN macro-metastases.
• Adjuvant chemotherapy timing and the number of involved SNs are critical factors influencing the risk of non-sentinel node metastasis.