Rapid Fire Session 2

In this video, Prof Dr Melanie Machiels discusses and comments on the data of some interesting studies presented during the Rapid Fire Session 2 at SABCS 2024.

The session started with a sub-study from the Alliance 11-202 trial, which explored the management of the axilla in clinically node-positive breast cancer patients who convert to node-negative status after primary systemic therapy. The trial compared outcomes between axillary lymph node dissection (ALND) with regional nodal irradiation versus axillary radiation alone with regional nodal irradiation. The sub-study specifically focused on nodal burden. Surprisingly, in patients undergoing ALND, 46% had additional involved lymph nodes despite a sentinel lymph node biopsy suggesting they were node-negative. This figure is considerably higher than previously reported in the ACOSOG Z0011 and AMAROS trials. Furthermore, ALND led to nodal upstaging in 25% of cases, predominantly among patients with hormone receptor-positive disease. These findings highlight the complexity of nodal management and suggest that ALND may uncover residual disease not detected by sentinel node biopsy alone.

The second presentation was a pooled analysis from the German Breast Group, combining data from several neoadjuvant trials. The study examined the prevalence and impact of micrometastases in clinically node-negative and node-positive patients following primary systemic therapy. Micrometastases were found in only 1.4% of initially node-negative patients and 3.7% of initially node-positive patients, indicating they are rare occurrences. However, the presence of micrometastases was associated with worse invasive disease-free survival, regardless of baseline nodal status. Interestingly, micrometastases did not affect overall survival. These findings suggest that micrometastases, while uncommon, may still have clinical significance, particularly for disease-free survival.

The third study, part of the AXSANA registry, evaluated the diagnostic accuracy of axillary ultrasound in determining nodal status after primary systemic therapy. The analysis revealed significant limitations: both false positive and false negative rates were 36%. For patients with false positive findings, overtreatment with unnecessary ALND was a concern. This highlights that axillary ultrasound alone is not a reliable tool for assessing nodal status in this setting, and its use could lead to substantial overtreatment in patients who might otherwise be spared surgery.

Next, interim findings from the ULTIMATE trial were shared. This trial assessed the safety of ultrahypofractionated (1 × 6 Gy) versus conventionally fractionated (5 × 2 Gy) radiotherapy boosts in breast cancer patients. The interim analysis focused on late normal tissue effects and cosmetic outcomes. No significant differences were found between the two regimens in these outcomes, suggesting that the ultrahypofractionated boost may be a safe and effective alternative to the longer fractionated approach, with potential implications for reducing treatment times and improving patient convenience.

A study from Danish researchers validated earlier findings on the prognostic significance of tumour-infiltrating lymphocytes (TILs). High TIL levels were associated with better survival outcomes, particularly in ER-negative patients, likely due to improved distant tumour control. Conversely, low TIL levels in ER-negative patients were linked to poorer survival and increased risk of distant recurrences, underscoring the importance of TILs as a prognostic marker. However, TIL levels did not predict the benefit of internal mammary node irradiation, suggesting their utility is more prognostic than predictive in this context.

The final presentation was a phase 3 randomised trial comparing olanzapine to prochlorperazine and placebo for refractory chemotherapy-induced nausea. Both olanzapine and prochlorperazine significantly reduced nausea, but olanzapine demonstrated superior efficacy, better control over peak nausea, and greater improvements in patient quality of life. Importantly, this is the first randomised evidence supporting olanzapine for this indication, paving the way for its integration into standard clinical practice to improve the management of chemotherapy-induced nausea and vomiting.