107 COVID 19 - Developing A Second Brain for Axillary Conservation During the Pandemic By Extrapolating Evidence On Technical Trends Of Sentinel Node Staging Of Axilla Into A Streamlined Recommendation

Introduction

Axillary conservation is the way forward after game changing trials like ACOSOG Z0011, surrogate trials like IBCSG,AMAROS, ALMANAC, on-going POSNOC, and newbie ATNEC have decreased the need to fiddle with the axilla. Current standard is the utilisation of double technique with radioisotope and blue dye to decrease false negative rates for true sentinel node retrieval.

Method

Literature search on the topic in the last two decades.

Results

The search yielded 197 publications which were subjected to a meticulous review.

Conclusions

Single agent radioisotope is recommended in palpable and good biology breast tumours. Use of single agent blue dye can be standardised in axillary tail tumours. It is also recommended when isotope mapping is logistically not feasible or during pandemics like COVID 19 where looming infrastructure challenges are prevalent. Dual agent technique should be considered in previously treated breast and axilla, neoadjuvant chemotherapy cohort, bad tumour biology, high BMI and macromastia groups for true nodal retrieval. Optimal number of nodes taken out should not be more than three (n = 3). Lower axillary sampling of not more than 3 nodes is recommended for troubleshooting. Magnetic tracing can be used as an adjunct to either single agent (RI/BD) technique when there is failure to localise the sentinel node.

Abstract PS2-43: Innovating a magnetic experience on wirral peninsula in the United Kingdom- our experience with magseed localisation of impalpable breast tumours and axillary node for therapeutic surgery and staging

INTRODUCTION Magseed is a novel localization technology in which a tiny seed is inserted to accurately mark the site of breast tumour. These can be detected intra-operatively by sentimag localization system. These can be implanted days prior to surgery and do not require use of radioactive material. It aids localization of impalpable breast lesions improving margin clearance rates. METHODS A study was undertaken of 50 patients undergoing Magseed localization of non-palpable breast lesions in rural and urban areas of Wirral Peninsula in the UK. Data including age, mode of localization (Stereo-guided/ Ultrasound guided), presentation (Symptomatic/Screen detected), and time to surgery after localization, size and weight of specimen, histology and re-excision rates was collected between June 2019 and November 2019. RESULTS A total of 50 patients had 52 Magseed inserted. n=14 were symptomatic, n=35 were screen detected and n=1 was an incidental finding on surveillance mammogram for a B3 lesion. All 50 patients had therapeutic surgery. 30 seeds were inserted on the right and 22 were inserted on the left (two were bilateral). 44 seeds were inserted under Ultrasound guidance and the rest were targeted under stereo guidance (n=8).Deployment of 2 Magseed resulted in malposition requiring wire localization. Mean age of subjects was 59.76 (range 31-81) years. Mean time to surgery after Magseed insertion was 8.04 (range 1-27) days. Mean weight of the specimen was 48.57(range 10-264) gm. Mean size of the lesions was 20.32 (range 8-65) mm. Redo surgery for margin clearance was performed bringing the re-excision rate to 15.38% (n=8). CONCLUSION We conclude that Magseed localization of breast tumours is a safe and reliable technique in terms of accuracy, localization and clearance of margins without any radiation concerns. Our re-excision rate for margin clearance is comparable to the national average. The only caveat we observed was localization of impalpable lesions prior to surgery in bulky breasts where we had to utilize wire guided localization on the day of surgery. Large scale data are lacking to compare Magseed localization with other localization techniques for non-palpable breast lesions.

Citation Format: Tahera Arif, Mohammed Shameem Absar, Jonathan Michael Lund. Innovating a magnetic experience on wirral peninsula in the United Kingdom- our experience with magseed localisation of impalpable breast tumours and axillary node for therapeutic surgery and staging [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS2-43.

Abstract PS2-39: A peninsular experience - developing a non-biopsy protocol for the female cohort 25-29 years with clinically typical fibroadenoma conforming to maxwell criteria on ultrasound

Abstract.Abstract1:

IntroAim: The aim of this study was to introduce a non -biopsy protocol in our department for benign breast lump referrals confirmed as typical U2/3 fibroadenoma on imaging. The cohort of women between 25-29 years of age with sonographic features (Maxwell non-biopsy criteria) U2/3 typical of fibroadenoma does not miss malignancy. Current UK guidance is not to biopsy sonographically typical fibroadenomas in women under 25 years. We have studied our population extending the radiological Maxwell criteria reflecting histologically benign outcomes even in this group of 25-29 years.MethodsMethods: Retrospectively data was collected of all women between 25-29 years of age undergoing core biopsy for ultrasound confirmed both simple and complex fibroadenomas at Clatterbridge General Hospital between 2014 and 2019 over a period of five years. The number of cancers picked up was compared with the number of referrals and the discordance between radiological diagnosis of fibroadenoma and histopathological confirmation of malignancy was recorded.ResultsResults: We saw increment in referrals in this group of young women from n=260 to n=386 over the five year study period. A total of 1707 referrals were made across five years. n=175 image guided core biopsies were carried out for U2,U3,U4 lesions appearing as fibroadenoma on ultrasound. Out of these (n=175), all lesions coded U2/3 (n=165) based on Maxwell criteria on ultrasound were negative for cancer. U4 lesions on ultrasound were confirmed as cancers mimicking fibroadenoma(n=10).ConclusionConclusion: This retrospective audit of 1707 patients provides sound evidence for safe non-biopsy of typical fibroadenomas in women 25-29 years when clinical and sonographic features meet strict criteria. We started using the non-biopsy protocol using Maxwell criteria for U2/3 lesions. We discharged women in this group if they met all the protocol criteria, i.e., their lesion does not appear suspicious clinically, has all the ultrasound appearances typical of a fibroadenoma U2/3, and they do not have any compounding circumstances (e.g., family history, genetic predisposition). As routine, we advise all women who are discharged without follow-up to examine their breasts regularly and return if they detect any changes including increase in lesion size. We need data to be audited prospectively and provide level 1 evidence to the same effect.

Citation Format: Tahera Arif, Mohammed Shameem Absar, Raman Vinayagam. A peninsular experience - developing a non-biopsy protocol for the female cohort 25-29 years with clinically typical fibroadenoma conforming to maxwell criteria on ultrasound [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS2-39.

P3-07-42: Lymphovascular Invasion Best Correlates with Presence of Nodal Metastasis in Sentinel Lymph Node Biopsy

Background. Sentinel lymph node biopsy (SLNB) biopsy is routinely practised for axillary staging with 25–30% having positive SLN. Tumour size is the most important parameter taken into consideration in decision making in node negative patients with a size cut off for 4–5cm dependant on different units. Lymphovascular invasion (LVI) and Ki-67 a cell-cycle antigen are known important prognostic markers along with the tumour grade, oestrogen receptor and herceptin receptor status.

Aim. To examine whether lymphovascular invasion, Ki-67 or any other factors can be used as a predictor for axillary lymph node involvement and hence prognosis.

METHODS. A prospective study of 264 patients with invasive breast cancer undergoing SLN biopsy between January 2009 and December 2010.

Histopathology reports were reviewed regarding LVI, Ki-67, grade, oestrogen, Progesterone and Herceptin receptor and SLN status. Stats direct was used to analyse data. Logistic regression was used and p-value calculated.

RESULTS. LVI (p value=0.0001) and size(p value=0.0273) were the two most significant factors associated with node positivity. Grade of tumour had a p-value of 0.0825 and Ki67 had a p-value of 0.5217 which were not significant.

Sentinel lymph node biopsy (SLNB) prior to primary chemotherapy (PC) in breast cancer patients

Abstract #5111

Background: Lymph node status is the single most important determinant of prognosis and is used for planning adjuvant therapy. Patient selection and timing of SLNB for PC continue to evolve; SLNB prior to PC may allow more accurate initial staging and prognostication and guide decisions about adjuvant treatment.
 Methods: 78 patients (pts) who were treated in the Cambridge Breast Unit as part of Neo-tAnGo (a multicentre PC trial). 57 were identified as potentially suitable for SLNB pre-PC (clinically node negative, non-inflammatory tumours 2–5cm in size). 38 had axillary ultrasound, and of these, 18 had sonographically suspicious nodes. 12/18 had confirmed nodal metastasis on core biopsy (CB) and had direct ALND post-PC. The remaining 20 patients had innocent nodes or were CB negative, of whom 19 underwent SLNB. A total of 19 patients in this subgroup did not undergo axillary ultrasound; 16 of these proceeded to ALND post-PC and 3 to SLN biopsy pre-PC according to unit policy at the time. A total of 22 (19 + 3) pts were available for analysis of SLN biopsy pre-PC in terms of time to treatment compared to the remainder of the centre's cohort in the Neo-tAnGo study. 42, (22 SLNB + 20 node positive on CB), were analysed as having axillary pathological staging before PC and compared to the other patient cohort on study.
 Results: The SLN was successfully identified in all 22 pts using dual localisation techniques with a mean SLN harvest of 2.8 nodes per patient (range 1–10). 6/22 pts (27%) were node positive, and 5 had single SLN involvement (4 macro-; 1 micro-) and one had a macro- and a micrometastasis in 2 different nodes. The mean time from diagnosis to start of PC in the SLN group was 23 days (range 8–43) compared 18 days (range 7–36) for the comparator cohort on study (p=0.02). When all 42 pts with pathological axillary assessment were analysed (including clinically node positive pts with tumours >5cm), there was no significant difference in time from diagnosis to start of PC for pts undergoing CB and/or SLNB (21 days) compared with no axillary assessment (17 days) (wilcoxon test p=0.10). The mean number of nodes removed on completion ALND was 9 (range 4–16). There was no evidence of any viable tumour or fibrosis in any of the non-SLN's (NSLN) examined. Amongst the group of 18 ultrasound/CB positive pts who underwent ALND without SLNB, nodal disease was found in 9 (50%) with evidence of pathological downstaging in 4 (22%).
 Conclusion: There is potential loss of staging information when SLNB is performed after PC and the clinical significance of a negative SLNB result in this setting is uncertain. A combination of axillary ultrasound (with CB) and SLNB can more accurately stage the axilla without significant overall delays in commencement of PC for clinically node positive and negative pts. Downstaging of disease in NLSN may occur in response to PC with a lower NSLN rate (0%) when compared to primary surgical treatment in smaller tumours (15–25%).

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 5111.

Value of axillary ultrasound and cytology in assessing nodal status preoperatively

Abstract #1007

Preoperative identification of axillary node involvement in early breast cancer allows correct surgical procedures to be performed and avoids second axillary operations. We compared preoperative axillary assessment using ultrasound ± cytology with the eventual histopathological results to identify the accuracy of preoperative axillary node assessment.
 Methods: Preoperative axillary ultrasound was used to identify the presence of suspicious or malignant nodes which were then confirmed with cytological assessment to allow management decisions regarding axillary clearance (or sentinel node biopsy (SNB) if nodes appeared negative).
 Results: Overall 79/365 (21%) early breast cancer patients had suspicious or malignant nodes on ultrasound, of which 78 were confirmed on cytology, thus avoiding an unnecessary SNB operation in these patients. Ultrasound and cytology accurately identified patients with ER negative (P=≤0.001), high grade (P=≤0.001) and large size tumours ≤20mm (P=≤0.001), with involved nodes. Only 11% ER negative compared to 46% ER positive tumours were incorrectly classified (P=0.002). In contrast ER positive, low grade, small tumours were most likely to have a false negative axillary assessment. Specificity of cytological assessment of nodes was 99% and sensitivity 54%.
 Conclusions: Axillary ultrasound combined with cytological assessment of suspicious nodes accurately identifies majority of women who require axillary clearance.
 


Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1007.

Colonic neoplastic polyps: biopsy is not efficient to exclude malignancy. The Trafford experience

The biological behaviour of the polyp depends entirely on its histological subtype. Adenomas are the classic precursors to carcinoma. Polyp biopsy can differentiate neoplastic (adenoma and carcinoma) from non-neoplastic polyps (hyperplastic, inflammatory, hamartomatous). Due to potential sampling error, biopsy does not always differentiate between adenoma and carcinoma. Our aim was to investigate the degree of this potential sampling error. We carried out a study to compare the results of biopsies vs. total tissue examinations in a cohort of 433 neoplastic polyps. In this study 18.5% of carcinomatous polyps show definitive malignant elements only when the entire polyp is presented to the pathologist. We have therefore adopted a special reporting template if the polypoidal tumour is either biopsied or incompletely excised. The study also showed that within adenomas there could be variance of architectural patterns between the biopsy and the whole specimen. In this series, biopsying malignant colonic polyps gives rise to 18.5% false negative results and therefore it is significantly less efficient in the diagnosis of malignancy compared to total polyp examination.