Recommendations for standardized pathological characterization of residual disease for neoadjuvant clinical trials of breast cancer by the BIG-NABCG collaboration

Abstract

Neoadjuvant systemic therapy (NAST) provides the unique opportunity to assess response to treatment after months rather than years of follow-up. However, significant variability exists in methods of pathologic assessment of response to NAST, and thus its interpretation for subsequent clinical decisions. Our international multidisciplinary working group was convened by the Breast International Group-North American Breast Cancer Group (BIG-NABCG) collaboration and tasked to recommend practical methods for standardized evaluation of the post-NAST surgical breast cancer specimen for clinical trials that promote accurate and reliable designation of pathologic complete response ( pCR) and meaningful characterization of residual disease. Recommendations include multidisciplinary communication; clinical marking of the tumor site (clips); and radiologic, photographic, or pictorial imaging of the sliced specimen, to map the tissue sections and reconcile macroscopic and microscopic findings. The information required to define pCR (ypT0/is ypN0 or ypT0 yp N0), residual ypT and ypN stage using the current AJCC/UICC system, and the Residual Cancer Burden system were recommended for quantification of residual disease in clinical trials.

The ever-evolving role of pathologists in the management of breast cancer with neoadjuvant treatment: recommendations based on the Spanish clinical experience

“…The consensus for the evaluation of the axilla during the diagnostic process was that axillary US should be performed to all breast cancer suspected patients that undergo CNB and in the case of suspicious lymph nodes detection, a biopsy (FNA or/and CNB) of them should be performed [37] with concomitant placement of a radiological marker into the biopsied node. This was in agreement with the current recommendations [17,18] and the results of our consensual and clinical practice questionnaire.…”

“…Following an extensive review of literature on the subject of pathological evaluation of post-NAST specimens of breast cancer, taking in account the experience from the Spanish clinical practice and paying special attention to the recently published recommendations of Provezano et al [17] and Bossuyt et al [18], two questionnaires, one containing assertions on relevant items of handling and analysing post-NAST breast cancer samples (consensus questionnaire) and the other questions about the Spanish daily breast cancer pathology practice (Clinical practice questionnaire) were designed by a committee of pathology experts on breast cancer to be discussed and subjected to consensual surveyance by the Delphi method.…”

“…Currently there are different classification systems with several relevant reviews [13][14][15][16], where recommendations for the assessment of pathologic response to NAST can be found. In recent time, NAST has been part of multicentre clinical trials and often recommendations for assessment of pathology specimens are elaborated during these trials [17,18]. The pathologist's task in assessing post-NAST specimens could get even more complicated by the fact that the definition of pCR is not uniformly accepted creating thus further challenging issues with the interpretation and reporting of the data [19].…”

“…The pathologist's task in assessing post-NAST specimens could get even more complicated by the fact that the definition of pCR is not uniformly accepted creating thus further challenging issues with the interpretation and reporting of the data [19]. Bossuyt et al and Provenzano et al in their respective studies [17,18] recommended that the post-NAST assessment and report should include information on pCR versus residual disease as defined by the FDA meta-analysis [9] (ypT0/is ypN0), AJCC/UICC ypT plus ypN stage and detailed quantification of residual disease (RCB system).…”

Correlation of the value of sonoelastography strain ratio with the degree of pathological regression in patients with locally advanced breast cancer undergoing neoadjuvant chemotherapy

“…Од-нако для возможности участия в международных ис-следованиях необходимо использовать иностранные системы, такие как I. D. Miller и S. Payne [14] и RCB (www.mdanderson.org / breastcancer_RCB). Большинство авторов систем для оценки степени ответа на терапию подчеркивают, что pCR обозначает полное отсутствие опухолевых клеток (как инфильтративного рака, так и рака in situ) [10,15].…”