Optical Emission Spectroscopy for the Real-Time Identification of Malignant Breast Tissue

Breast conserving resection with free margins is the gold standard treatment for early breast cancer recommended by guidelines worldwide. Therefore, reliable discrimination between normal and malignant tissue at the resection margins is essential. In this study, normal and abnormal tissue samples from breast cancer patients were characterized ex vivo by optical emission spectroscopy (OES) based on ionized atoms and molecules generated during electrosurgical treatment. The aim of the study was to determine spectroscopic features which are typical for healthy and neoplastic breast tissue allowing for future real-time tissue differentiation and margin assessment during breast cancer surgery. A total of 972 spectra generated by electrosurgical sparking on normal and abnormal tissue were used for support vector classifier (SVC) training. Specific spectroscopic features were selected for the classification of tissues in the included breast cancer patients. The average classification accuracy for all patients was 96.9%. Normal and abnormal breast tissue could be differentiated with a mean sensitivity of 94.8%, a specificity of 99.0%, a positive predictive value (PPV) of 99.1% and a negative predictive value (NPV) of 96.1%. For 66.6% patients all classifications reached 100%. Based on this convincing data, a future clinical application of OES-based tissue differentiation in breast cancer surgery seems to be feasible.

Back to the future: breast surgery with tumescent local anesthesia (TLA)?

PURPOSE

Breast surgery is usually performed under general anesthesia. Tumescent local anesthesia (TLA) offers the possibility to anesthetize large areas with highly diluted local anesthetic.

METHODS

In this paper, the implementation, and experiences with TLA in the field of breast surgery are discussed.

CONCLUSION

For carefully selected indications, breast surgery in TLA represents an alternative to ITN.

Evaluation of sonographic detectability of different markers within an in vitro simulation model of the axilla

PURPOSE

Clip-marking of axillary lymph nodes with initial biopsy-confirmed metastasis is required for targeted axillary dissection (TAD), which includes sentinel lymph node dissection (SLND) and selective localization and removal of the clipped targeted lymph node. There have been several studies which examined the feasibility of TAD in routine clinical use. In this context, the optimal clip visualisation was noted as one of the crucial limiting factors. We, therefore, evaluated the sonographic detectability of 10 different commercially available markers within an in vitro model simulating the anatomical composition of the axilla.

METHODS

In this standardised model consisting of porcine fat with 30 mm thickness, the visibility of a total of ten markers was analysed in all 3 planes (parallel, diagonal, orthograde) with wire guidance and then classified into either "visibility good", "visibility moderate" or "visibility poor" with regard to the alignment of the transducer. Additionally, "real-life conditions" were simulated, in which the markers were searched without any wires guidance.

RESULTS

It was observed that, while not all markers are detectable in fatty tissue, markers with spherical shape (non-embedded Inconel or Nitinol) or rectangular-shaped Titanium markers with embedded material have a clear advantage. 3D-shaped markers can always be detected in all three axes, which is of particular importance in the axilla with its pyramid shape and fatty tissue.

CONCLUSION

The shape and the embedding of the material play a crucial role for visibility and efficacy of the marker, as reliable marking of suspicious and pathological axillary lymph nodes is essential for TAD.

Residual Axillary Burden After Neoadjuvant Chemotherapy (NACT) in Early Breast Cancer in Patients with a priori Clinically Occult Nodal Metastases - a transSENTINA Analysis

Background Among patients with breast cancer undergoing neoadjuvant chemotherapy (NACT), the association between pathological complete remission (pCR) in the breast and clinical/pathological parameters is well established, whereas the association between these parameters and residual axillary involvement after NACT remains unclear.

Methods Patients with clinically occult nodal metastases (i.e. negative by clinical assessment but positive by SLNB prior to NACT, i.e. Arm B of the SENTINA trial) were included in the presented analysis. All patients received a second sentinel lymph node biopsy (SLNB) and axillary dissection after NACT. Univariate and multivariate analyses were carried out to evaluate the association between clinical/pathological parameters and axillary involvement after NACT.

Results Arm B of the SENTINA study contained 360 patients, 318 of which were evaluable for this analysis. After NACT, 71/318 (22.3%) patients had involved SLNs or non-SLNs after NACT. Overall, 71/318 (22.3%) patients achieved a pCR in the breast. Associations of extranodal spread, lack of multifocality and pCR in the breast with residual axillary burden were statistically significant. In a descriptive analysis including all patients with clinically negative axilla before NACT in the SENTINA trial 1.2% of triple negative (TN) patients and 0.5% of HER/2 positive patients had residual axillary disease in case of a breast pCR.

Conclusions Patients in the SENTINA trial with clinically negative axilla and involved SLNs still carried a significant risk of nodal metastases after NACT. However, the risk of residual axillary burden was particularly low in TN and HER/2 positive tumors in case of a breast pCR.

Non-negative least squares computation for in vivo myelin mapping using simulated multi-echo spin-echo T2 decay data

Multi-compartment T₂ mapping has gained particular relevance for the study of myelin water in the brain. As a facilitator of rapid saltatory axonal signal transmission, myelin is a cornerstone indicator of white matter development and function. Regularized non-negative least squares fitting of multi-echo T₂ data has been widely employed for the computation of the myelin water fraction (MWF), and the obtained MWF maps have been histopathologically validated. MWF measurements depend upon the quality of the data acquisition, B₁⁺ homogeneity and a range of fitting parameters. In this special issue article, we discuss the relevance of these factors for the accurate computation of multi-compartment T₂ and MWF maps. We generated multi-echo spin-echo T₂ decay curves following the Carr-Purcell-Meiboom-Gill approach for various myelin concentrations and myelin T₂ scenarios by simulating the evolution of the magnetization vector between echoes based on the Bloch equations. We demonstrated that noise and imperfect refocusing flip angles yield systematic underestimations in MWF and intra-/extracellular water geometric mean T₂ (gmT₂ ). MWF estimates were more stable than myelin water gmT₂ time across different settings of the T₂ analysis. We observed that the lower limit of the T₂ distribution grid should be slightly shorter than TE₁ . Both TE₁ and the acquisition echo spacing also have to be sufficiently short to capture the rapidly decaying myelin water T₂ signal. Among all parameters of interest, the estimated MWF and intra-/extracellular water gmT₂ differed by approximately 0.13-4 percentage points and 3-4 ms, respectively, from the true values, with larger deviations observed in the presence of greater B₁⁺ inhomogeneities and at lower signal-to-noise ratio. Tailoring acquisition strategies may allow us to better characterize the T₂ distribution, including the myelin water, in vivo.

Percutaneous Ultrasound-Guided Core Needle Biopsy: Comparison of 16-Gauge versus 14-Gauge Needle and the Effect of Coaxial Guidance in 1065 Breast Biopsies - A Prospective Randomized Clinical Noninferiority Trial

PURPOSE

 Ultrasound-guided core needle biopsy (CNB) is considered the standard assessment to diagnose sonographically visible suspicious breast mass lesions. Based on nonrandomized trials, the current German guidelines recommend at least three cylinders with ≤ 14-gauge needle biopsy. However, no recommendation is made as to how many specimens are needed with a smaller needle size, such as 16-gauge, or if biopsy with coaxial guidance improves diagnostic accuracy and quality. Therefore, in a prospective monocentric unblinded randomized controlled clinical noninferiority trial, the diagnostic accuracy of 16-gauge versus 14-gauge core needle biopsy, with and without coaxial guidance, was evaluated.

MATERIALS AND METHODS

 1065 breast biopsies were included in order to analyze the number of core samples necessary to obtain an appropriate rate of diagnostic quality adequate for histological evaluation, and to achieve high diagnostic accuracy and diagnostic yield. Histological results were verified by surgery or long-term follow-up of at least two years up to five years.

RESULTS

 In order to obtain an additive diagnostic accuracy of > 99 %, a minimum of two cylinders with 14-gauge biopsy were required. The diagnostic accuracy and the diagnostic quality of 14-gauge biopsy were not affected by the coaxial technique. When performing a 16-gauge biopsy, five cylinders were required to achieve an additive diagnostic accuracy of > 99 %. Without coaxial guidance, 16-gauge CNB required at least three samples, whereas five needle passes with coaxial-guided 16-gauge biopsy were needed.

CONCLUSION

 The diagnostic accuracy and quality of ultrasound-guided 16-gauge core needle biopsy were inferior to the 14-gauge needle size, regardless of the use of a coaxial technique.

Factors associated with axillary conversion after neoadjuvant chemotherapy in initially node positive breast cancer patients: A transSENTINA analysis

567

Background: Current study concepts in early breast cancer after neoadjuvant chemotherapy (NAT) are aiming at reducing morbidity by omission of axillary surgery in selected patients. Selection criteria for this strategy have to include the probability of conversion from cN1 to ycN0. We analyzed the association of clinical/pathological parameters and axillary conversion with data from arms C and D of the SENTINA trial (Kühn T et al., Lancet Oncol 2013). Methods: Patients were recruited to Arms C/D of the SENTINA trial in case they presented with clinically positive nodes before NAT. Based on their response to NAT they were then assigned to either arm C (clinically conversion to ycN0) or arm D (no clinical conversion (ycN+). In both the pre- and post-NAT scenarios, clinically involved lymph nodes were defined as palpable and/or suspect by ultrasound. Univariate logistic regression analyses were carried out to evaluate the association between clinical/pathological parameters and axillary conversion after NAT. Results: Of the 892 patients in arms C and D of the SENTINA trial 716 were evaluable for this analysis. After NAT, 593 patients converted to ycN0 and were therefore assigned to arm C; in contrast, 123 patients still had involved lymph nodes after NAT (ycN+) and were assigned to Arm D. Arms C and D were compared regarding the clinical/pathological parameters tumor diameter by ultrasound before and after NAT, grading, multifocality, ER status, PR status, HER2 status, pathological complete remission in the breast (breast pCR), morphology, lymphovascular invasion (LVI) and hemangiosis. Only small tumor diameter after NAT (p = 0.0038), achievement of breast pCR (p = 0.0001) and lack of LVI (p = 0.0009) were positively associated with axillary conversion from cN1 to ycN0 after NAT. Conclusions: Because of the small patient number in arm D, we were not able to identify an association between parameters of tumor biology (ER, PR, HER2 and TN status) and axillary conversion. However, favorable response of the primary tumor (represented both clinically by tumor diameter after NAT and pathologically by pCR in the breast) were positively associated with conversion from cN1 to ycN0. These results justify including patients with clinical and pathological response of the primary tumor in trials investigating de-escalation of axillary surgery after NAT.

Abstract P1-20-02: Axillary conversion rates according to breast cancer subtype among patients with pathological complete remission (pCR) in the breast after primary systemic therapy (PST) - A transSENTINA subproject

Background: Modern chemotherapy carries a high potential of converting patients with a clinically positive axilla (cN+) prior to PST to a clinically (ycN0) or even pathologically (ypN0) negative axilla after PST. Patients achieving a pathological complete remission (pCR) in the breast after PST carry a favorable prognosis including a high probability of axillary conversion. Among patients with highly chemosensitive tumors (i.e. high pCR rate), axillary staging may be adjusted accordingly.

Methods: In a retrospective study we analyzed the relation between breast pCR, nodal pCR and the intrinsic subtype in clinically node-positive patients who convert to ycN0. Arm C of the SENTINA trial included patients converting from cN+ to ycN0 through PST as part of a prospective study. Patients were categorized into luminal (HR+/HER2-), triple negative (TN; HR- / HER2-), triple positive (TP (HR+ / HER2+), and HER2 pos ER neg HER2 positive (HR- / HER2+) subgroups.

Results: Overall 416 of 596 patients were included (exclusions due to missing parameters) with 167 luminal, 119 TN, 77 TP and 56 HER2 pos ER neg HER2 positive tumors. Among all patients, pathological axillary conversion occurred in 154 (80.21%) and 91 (32.97%) cases among patients with and without pCR, respectively (odds ratio (OR) 0.23, p-value < .001). Among all subgroups, there was a significant increase in the probability of axillary conversion in case of pCR. Axillary conversion rates for patients with and without pCR were, respectively:

• TN 56 (84.85%) and 24 (45.28%)• TP 33 (73.33%) and 12 (37.50%)

• Luminal 18 (66.67%) and 34 (24.29%)

• HER2 pos ER neg 33 (91.67%) and 9 (45.00%)

We identified patient subgroups, among whom conversion rates were > 90%, i.e. among patients with (i) TN breast cancer and age at diagnosis < 50 years (91.89%) and (ii) HER2 pos ER negitive breast cancer and grade 3 disease (94.74%) or age > 50 years (94.44%).

Conclusion: Our analysis demonstrates that among patients with pCR, probabilities of axillary conversion were significantly higher among patients with pCR compared to patients without pCR. However, results differed according to biological breast cancer subtypes, with more aggressive subgroups presenting with higher probability of axillary conversion. We identified subgroups of patients among whom the rate of axillary residual disease after PST was lower compared to the false-negative rate of sentinel lymph node biopsy. Provided independent validation of our results, these subgroups may benefit from de-escalation of axillary stagingsurgery.

Citation Format: Cornelia Kolberg-Liedtke, Hans-Christian Kolberg, Maja Krajewska, Ingo Bauerfeind, Tanja Fehm, Barbara Fleige, Gisela Helms, Annette Lebeau, Annette Staebler, Sibylle Loibl, Michael Untch, Thorsten Kühn. Axillary conversion rates according to breast cancer subtype among patients with pathological complete remission (pCR) in the breast after primary systemic therapy (PST) - A transSENTINA subproject [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-20-02.

Ultrasound-Assisted Tumor Surgery in Breast Cancer - A Prospective, Randomized, Single-Center Study (MAC 001)

PURPOSE

 Breast-conserving therapy is associated with a risk of tumor-involved margins. For intraoperative orientation, non- palpable or indistinctly palpable lesions are wire-marked prior to surgery. Ultrasound-guided surgery has the potential to reduce the number of tumor-involved margins. In the MAC 001 trial we evaluated ultrasound-guided breast-conserving surgery compared to wire-guided surgery with regard to free tumor margins, duration of surgery and resection volume.

MATERIALS AND METHODS

 In this randomized, prospective, single-center controlled trial, patients with ductal invasive breast cancer were recruited for either ultrasound-guided or wire localization surgery. Primary outcomes were tumor-free resection margins, the reoperation rate and the resection volume in each group. The results were analyzed by intention to treat. The trial was registered under ClinicalTrials.gov NCT02222675.

RESULTS

 56 patients were assessed, and 47 patients were evaluated in the trial. 93 % (25/27) of the patients in the ultrasound arm had an R0 reoperation compared to 65 % (13/20) in the wire localization control arm. This result was statistically significant (p = 0.026). No statistical difference was found for the resection volume or the duration of surgery between the two arms. No major complication was seen in either arm.

CONCLUSION

 Ultrasound-assisted breast surgery significantly increases the possibility of tumor-free margins and therefore reduces the risk of reoperations. Breast surgeons should be trained in ultrasound and ultrasound should be available in every breast surgery operating room.

Association between tumor biology and occult lymph node metastases before and after primary neoadjuvant therapy (NAT) for patients with early breast cancer

518

Background: Scientific efforts aim at a reduction of axillary morbidity through reduced axillary intervention among patients with early breast cancer. However, it is still unclear if this approach is feasible in all subtypes based on their risk of axillary involvement. We analyzed the association of tumor biology and occult axillary involvement with data from arms A and B of the SENTINA trial (Kühn T et al., Lancet Oncol 2013). Methods: Patients were included if they presented with a clinically negative axilla before NAT (arms A and B) and stratified according to tumor biology. All patients received SLNB before NAT, in cases of negative SLNB without further axillary surgery (Arm A) and in cases of positive SLNB (Arm B) with SLNB and axillary dissection after NAT. Logistic and linear regression analyses were carried out to evaluate the association between tumor biology and axillary involvement before and after NAT. Results: Of the 1022 patients in arms A and B of the SENTINA trial 926 were evaluable for this analysis. Of these, 27.9% had triple negative (TN), 16.3% hormone receptor (HR) and HER2 positive (triple positive = TP), 47.6% HR positive and HER2 negative (luminal) and 8.2% HR negative and HER2 positive (HER2) tumors. 39.7% of the luminal, 28.9% of the HER2, 19% of the TN and 47% of the TP tumors had involved SLN before NAT. Subgroup comparisons showed a significant difference between luminal and TN (p < 0.0001), whereas the differences between luminal and TP (p = 0.115) and HER2 (p = 0.077) were not statistically significant. The 317 patients with involved SLN prior to NAT received SLNB and axillary dissection after completion of NAT. The analysis after NAT showed trends for lower rates of involved lymph nodes for the high-risk groups (TN 20% / TP 14.3% / HER2 8.7%) compared to luminal tumors (27.6%) without reaching statistical significance. Conclusions: Our analysis demonstrates that among patients enrolled in the SENTINA trial, patients with triple negative disease have the lowest risk for occult lymph node metastases at initial presentation. Our results do not justify more intense local intervention among patients with triple negative breast cancer.

Abstract PD8-02: Residual axillary involvement in early breast cancer in patients with positive sentinel nodes after neoadjuvant chemotherapy (NACT)

Background:The association between pathological complete remission (pCR) in the breast and clinical/pathological parameters is well established, whereas the role of these parameters in the prediction of residual axillary involvement after NACT is unclear. The goal is to identify a subset of patients who do not need axillary treatment. We used data from Arm B of the SENTINA trial to analyze this association.

Methods:Patients from arm B of the SENTINA trial with clinically and sonographically unsuspicious axillary nodes but with histologically proven involvement of SLNs prior to NACT were analyzed. All patients had SLNB and axillary dissection after NACT. Univariate analyses were performed to evaluate the association between clinical/pathological parameters and axillary involvement after NACT.

Results:Arm B of the SENTINA study contained 360 patients, 318 of which were evaluable with respect to the above parameters. After NACT 71/318 (22.3%) patients had involved SLNs or non-SLNs; 71/318 (22.3%) had a pCR in the breast. We observed a significant association between pCR in the breast and negative ER status, negative PR status, positive HER2 status, triple negative (TN) status, tumor size before and after NACT, multifocality, lobular morphology and axillary involvement after NACT. Regarding residual axillary burden only the associations with lobular morphology, extracapsular invasion, multifocality, positive HER2 status and pCR in the breast were statistically significant.

Conclusion:Our analysis demonstrates that patients enrolled in the SENTINA trial with clinically and sonographically unsuspicious axillary nodes but proven histological involvement of SLNs prior to NACT have positive axillary nodes in 22.3 % after NACT. This rate is confirming similar results from other groups. Although we found statistically significant associations between pCR in the breast and clinical/pathological parameters, only the association between lobular type, extracapsular invasion, positive HER2 status and pCR in the breast and residual axillary involvement after NACT were statistically significant. We cannot clearly identify a subset of patients for whom axillary treatment after NACT could be safely omitted if SLNs were positive. Our data are well in line with recently presented data demonstrating that the association between pCR in the breast and free axillary nodes after NACT is particularly strong in patients with TN and HER2 positive tumors. This question will be addressed in future trials currently under development.

Citation Format: Kolberg H-C, Liedtke C, Bauerfeind I, Fehm T, Fleige B, Hauschild M, Helms G, Lebeau A, Schmatloch S, Schrenk P, Schwentner L, Stäbler A, Loibl S, Untch M, Kühn T. Residual axillary involvement in early breast cancer in patients with positive sentinel nodes after neoadjuvant chemotherapy (NACT) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD8-02.

Abstract PD8-03: Conversion rates from positive to negative axillary involvement in breast cancer patients presenting with biopsy-proven axillary metastases prior to primary systemic therapy (PST) – A transSENTINA subproject

Background:

Modern chemotherapy carries a high potential of converting patients with clinically suspicious axillary nodes (cN+) prior to PST to clinically (ycN0) or pathologically (ypN0) negative nodes after PST. Clinical and sonographical axillary assessment, however, may be inadequate and therefore pathological assessment of suspicious axillary nodes is recommended. We analyzed the association between clinical / pathological parameters and positive to negative conversion in patients with biopsy-proven axillary metastases in Arm C of the SENTINA trial (i.e. patients with “true conversion”).

Methods:

Arm C of the SENTINA trial included patients converting from cN+ to ycN0 through PST from a prospective study. We limited our analysis to patients who had biopsy-proven axillary involvement. Univariate regression analysis was carried out to assess the association between patients with vs. without axillary disease after PST in i) patients with biopsy-proven involvement and ii) patients without biopsy proof of metastases.

Results:

Among 596 patients in arm C of the SENTINA trial with clinically and or sonographically suspicious ipsilateral axillary nodes, 439 (73,7%) 157 (26,3%) patients had a biopsy. In 152 patients (96,8%), lymph node metastases were confirmed and in 5 patients (3,2%), no malignant cells were identified. In both groups, we found a significant association (p&lt;0,05) between increased rate of axillary conversion and small tumor diameter after PST, absence of multifocality, absence of lymphovascular invasion (LVI), ER and/or PR negativity, HER2 negativity, triple negative disease, and complete pathological response (pCR). No multiple testing corrections were performed due to an exploratory setting. However, only among patients with biopsy-proven involvement prior to PST, we found grade-3-tumors to be significantly associated with reduced probability of residual axillary involvement (76.1 vs. 33.8%, compared to G1 and G2, p=0.0323).

Conclusion:

Our analysis demonstrates that in patients with biopsy-proven axillary involvement before NST, parameters associated with axillary conversion are similar to those among patients classified as having nodal disease based on clinical and or sonographical assessment (cN+). Our analyses demonstrate that in biopsy-proven axillary metastases before NST, modern chemotherapy regimens result in significant rates of axillary conversion. This underscores the need to deescalate axillary staging / treatment with the goal to further avoid unnecessary axillary surgery.

Citation Format: Liedtke C, Kolberg H-C, Krajewska M, Bauerfeind I, Fehm T, Fleige B, Helms G, Lebeau A, Staebler A, Loibl S, Untch M, Kühn T. Conversion rates from positive to negative axillary involvement in breast cancer patients presenting with biopsy-proven axillary metastases prior to primary systemic therapy (PST) – A transSENTINA subproject [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD8-03.

Validation of a Nomogram Predicting Non-Sentinel Lymph Node Metastases among Patients with Breast Cancer after Primary Systemic Therapy - a transSENTINA Substudy

Background

Prediction of non-sentinel lymph node (SLN) status after primary systemic therapy (PST) may allow tailored axillary staging. The aim of this analysis was to compare established nomograms from i) the primary operative (n = 6) and ii) the neoadjuvant (n = 1) setting with an optimized nomogram to predict non-SLN status in patients after PST.

Methods

181 patients converting from cN1 prior to PST to ycN0 but found to have a histologically positive SLN in the SENTINA trial were analyzed. Established models were applied. An optimized model was compiled using univariate and subsequent multivariable logistic regression (backward selection, likelihood ratio test).

Results

Area-under-the-curve (AUC) values from the primary operative models showed sufficient performance (0.82-0.71). For the neoadjuvant model, the AUC was found to be inferior to prior analyses (0.66) but within published confidence intervals. The SENTINA nomogram comprised the diameter of the largest lymph node (p = 0.006, odds ratio (OR) = 1.19), tumor size prior to PST (p = 0.085, OR = 1.31), and number of all positive SLN (p = 0.083, OR = 2.04). This model was validated using a separate cohort of arm C (n = 168, AUC 0.79, 95% confidence interval 0.74-0.85).

Conclusion

We validated 7 models of prediction of non-SLN among patients showing axillary conversion through PST. Our own 'SENTINA nomogram' yielded AUC values comparable to previous nomograms.

Systematic analysis of parameters predicting pathological axillary status (ypN0 vs. ypN+) in patients with breast cancer converting from cN+ to ycN0 through primary systemic therapy (PST)

Optimization of axillary staging among patients converting from clinically node-positive disease to clinically node-negative disease through primary systemic therapy is needed. We aimed at developing a nomogram predicting the probability of positive axillary status after chemotherapy based on clinical/pathological parameters. Patients from study arm C of the SENTINA trial were included. Univariable/multivariable analyses were performed for 13 clinical/pathological parameters to predict a positive pathological axillary status after chemotherapy using logistic regression models. Odds ratios and 95%-confidence-intervals were reported. Model performance was assessed by leave-one-out cross-validation. Calculations were performed using the SAS Software (Version 9.4, SAS Institute Inc., Cary, NC, USA). 369 of 553 patients in Arm C were included in multivariable analysis. Stepwise backward variable selection based on a multivariable analysis resulted in a model including estrogen receptor (ER) status (odds ratio (OR) 3.916, 95% confidence interval (CI) 2.318-6.615, p < 0.001), multifocality (OR 2.106, 95% CI 1.203-3.689, p = 0.0092), lymphovascular invasion (OR 9.196, 95% CI 4.734-17.864, p < 0.001), and sonographic tumor diameter after PST (OR 1.034, 95% CI 1.010-1.059, p = 0.0051). When validated, our model demonstrated an accuracy of 70.2% using 0.5 as cut-point. An area under the curve of 0.81 was calculated. The use of individual parameters as predictors of lymph node status after chemotherapy resulted in an inferior accuracy. Our model was able to predict the probability of a positive axillary nodal status with a high accuracy. The use of individual parameters showed reduced predictive performance. Overall, tumor biology was the strongest parameter in our models.

Systematic analysis of parameters predicting pathological axillary status (ypN0 vs. ypN+) in patients converting from cN+ to ycN0 through primary systemic therapy (PST)

560

Background: Optimization of axillary staging in patients converting from cN+ to ycN0 through PST is needed. The aim of this analysis was to develop a nomogram predicting the probability of ypN+ after PST based on clinical/pathological parameters. Methods: Patients converting from cN+ to ycN0 through PST from a prospective study (SENTINA arm C) were included. Univariate/multivariate analyses were carried out for 14 clinical/pathological parameters to predict ypN+ using logistic regression models. Odds ratios and 95% confidence intervals were reported. Model performance was assessed by leave-one-out cross-validation (LOOCV at .5 cut-offs) and ROC analyses. Calculations were performed using the SAS Software (Version 9.4). Results: 553 patients were assessed. Stepwise backward variable selection based on a multivariate analysis of all significant parameters resulted in a model (5M, Table, N = 369 evaluable) including ER (3.81; 2.25-6.44), multifocality (2.22; 1.26-3.92), LVI (9.16; 4.68-17.90), detection of SLN after PST (.50; .26-.95) and ycT (1.03; 1.01-1.06). In LOOCV, this model had an area under the curve of .81. Multivariate analysis of parameters available preoperatively showed an association between ypN0/ypN+, ER and ycT. Full subset selection resulted in a model (2M, N = 414) containing only ER (4.36; 2.80, 6.81) and ycT (1.04; 1.02, 1.07). Conclusions: A prediction model including parameters evaluable before/after definitive surgery resulted in a nomogram with acceptable accuracy. Limitation to parameters evaluable before surgery (i.e. ER, ycT) showed reduced accuracy that was comparable/superior to accuracy of using individual parameters. Since tumor biology was the strongest parameter in our models, we hypothesize that modern tumor biologic parameters such as gene expression profiling might optimize prediction of axillary status after PST improving patient counseling. [Table: see text]

Abstract P3-13-06: Development and validation of a nomogram predicting pathological axillary status (ypN0 vs. ypN+) in a subgroup of patients converting from cN+ to ycN0 through neoadjuvant therapy (NAT) – A transSENTINA substudy

Background: Particularly among patients converting from cN+ to ycN0 status through neoadjuvant therapy (NAT) the optimal method and extent of axillary staging is unclear. The aim of this analysis was to develop a nomogram predicting the probability of positive axillary status (ypN+) after PST among these patients based on clinical and pathological parameters.

Methods:Patients converting from cN+ to ycN0 due to PST included in a prospective study (SENTINA, Arm C) were included. Univariate and multivariate analyses were carried out to evaluate the association between 14 clinical/pathological parameters and pathological axillary status (ypN0 vs ypN+) using logistic regression models. Model accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were assessed applying leave-one-out cross-validation (LOOCV) and ROC analyses. Different cut-points were evaluated. Calculations were performed using the SAS Software (Version 9.4, SAS Institute Inc., Cary, NC, USA.).

Results: Arm C contained 553 patients, 369 patients were evaluable with respect to the above parameters. Univariate analyses revealed a significant association between pathological axillary status and ER status (odds ratio (OR) 4.05, 95% confidence interval (95%CI) 2.81-5.83), PR status (OR 3.07, 95%CI 2.16-4.36), multifocality (OR 2.37, 95%CI 1.57-3.58), lymphovascular invasion (OR 8.61, 95%CI 5.12-14.46), detection of a SLN after NAT (OR .56, 95%CI .36-.87), detection method (IHC vs routine: OR .46, 95%CI .27-.78; IHC vs serial HE: OR .72, 95%CI .49-1.07; serial hematoxylin eosin (HE) vs routine: OR .639, 95%CI .39-1.04), clinical tumor size (OR 1.051, 95%CI 1.03-1.07) and pCR-status in the breast (ypT0 and ypTis vs others, OR .11, 95%CI .08-.17). A multivariate model was fitted including significant clinical parameters. Stepwise backward variable selection was carried out resulting in a model including ER status (OR 3.81, 95%CI 2.25-6.44), multifocality (OR 2.22, 95%CI 1.26-3.92), LVI (OR 9.16, 95%CI 4.68-17.90), detection of a SLN after NAT (OR .50, 95%CI .26-.95) and clinical tumor size (OR 1.03, 95%CI 1.01-1.06). In LOOCV, this model demonstrated an accuracy of 73% (sensitivity 73%, specificity 72%, PPV 75%, NPV 70%) using .5 as cut-off. Based on the performed ROC analysis an area under the curve (AUC) of 0.81 was calculated.

Conclusion: A model using ER status, multifocality, LVI, detection of a SLN after NAT and clinical tumor size was built to predict pathological axillary status (ypN+) with a high accuracy. If successfully validated based upon an independent dataset, this nomogram could allow advising patients for / against axillary surgery in case of clinical axillary conversion after NAT.

Citation Format: Liedtke C, Kolberg H-C, Kerschke L, Goerlich D, Bauerfeind I, Fehm T, Fleige B, Hauschild M, Helms G, Lebeau A, Schmatloch S, Schrenk P, Schwentner L, Staebler A, von Minckwitz G, Loibl S, Untch M, Kuehn T. Development and validation of a nomogram predicting pathological axillary status (ypN0 vs. ypN+) in a subgroup of patients converting from cN+ to ycN0 through neoadjuvant therapy (NAT) – A transSENTINA substudy [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P3-13-06.

Abstract P3-01-14: A nomogram to predict the likelihood of axillary non-sentinel lymph node metastases in sentinel lymph node positive primary breast cancer patients

Background:

Completion of axillary lymph node dissection (ALND) was long lasting standard in patients with non-metastatic primary breast cancer (PBC) and axillary sentinel lymph node (SLN) involvement. However, this approach is currently questioned since recent prospective trials have found that some SLN-positive women with PBC might not benefit from subsequent ALND. Nomograms that estimate the probability of further non-sentinel lymph node (NSLN) metastases could guide clinical decisions.

Methods:

We compared the predictability of three different nomograms (MSKCC, Stanford University, Cambridge) on the NSLN status with an own logistic regression model in a training and validation set. SLN-positive women who underwent primary surgery including ALND at Tuebingen University, Germany, between 06/2005 - 12/2009 (training set) and 01/2010 - 02/2012 (validation set) were available for this analysis. The area under the receiver operating characteristics (ROC) curve was calculated for each nomogram.

Results:

295 and 175 patients were included into the training and validation set, respectively. Of these 118 (40%) and 57 (33%) patients were NSLN-positive. Variables within our model were tumor size, proportion of positive SLNs, size of SLN metastases, lymphangiosis carcinomatosa, multicentricity and extracapsular invasion. The respective area under the ROC curve values for the MSKCC / Stanford University / Cambridge / own regression model were 0.73 / 0.70 / 0.63 / 0.75 in the training set and 0.73 / 0.66 / 0.52 / 0.73 in the validation set.

Conclusion:

The predictability of our logistic regression model was comparable to the MSKCC nomogram and superior to the Stanford University and Cambridge nomogram. Although a training and a validation set was used, further testing on an independent patient population is warranted.

Citation Format: Hartkopf AD, Brucker SY, Helms G, Henzel M, Hahn M, Wallwiener M, Schoenfisch B, Taran F-A, Fehm TN. A nomogram to predict the likelihood of axillary non-sentinel lymph node metastases in sentinel lymph node positive primary breast cancer patients. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-01-14.

ICG Fluorescence Technique for the Detection of Sentinel Lymph Nodes in Breast Cancer: Results of a Prospective Open-label Clinical Trial

Introduction: Detection of sentinel lymph nodes (SLN) is the standard procedure to evaluate axillary lymph node status in breast cancer. In addition to known and established procedures such as the blue dye method and scintigraphy, this study investigated the efficacy of a method based on use of the fluorescent dye indocyanine green (ICG). Patients and Method: A total of 126 women with breast cancer histologically verified by punch biopsy were studied during surgical removal of SLN. In addition to SLN marking with technetium and scintigraphy, intra-individual comparison was done using indocyanine green (ICG) for marking instead of the standard blue dye. Results: Scintigraphy had a detection rate of 96 %; the detection rate with ICG was just under 89 %. A body mass index (BMI) > 40 was found to be a limiting factor for the fluorescent method. Investigation into potential toxicities associated with the use of the fluorescent dye ICG revealed no systemic or even local side effects. The fluorescent method was found to be significantly less expensive than the scintigraphy method. Conclusion: The ICG fluorescence technique for the detection of SLN was found to be a valid and feasible method in clinical practice when compared directly with the blue dye method and scintigraphy.

Disentangling in vivo the effects of iron content and atrophy on the ageing human brain

Evidence from magnetic resonance imaging (MRI) studies shows that healthy aging is associated with profound changes in cortical and subcortical brain structures. The reliable delineation of cortex and basal ganglia using automated computational anatomy methods based on T1-weighted images remains challenging, which results in controversies in the literature. In this study we use quantitative MRI (qMRI) to gain an insight into the microstructural mechanisms underlying tissue ageing and look for potential interactions between ageing and brain tissue properties to assess their impact on automated tissue classification. To this end we acquired maps of longitudinal relaxation rate R1, effective transverse relaxation rate R2* and magnetization transfer - MT, from healthy subjects (n=96, aged 21-88 years) using a well-established multi-parameter mapping qMRI protocol. Within the framework of voxel-based quantification we find higher grey matter volume in basal ganglia, cerebellar dentate and prefrontal cortex when tissue classification is based on MT maps compared with T1 maps. These discrepancies between grey matter volume estimates can be attributed to R2* - a surrogate marker of iron concentration, and further modulation by an interaction between R2* and age, both in cortical and subcortical areas. We interpret our findings as direct evidence for the impact of ageing-related brain tissue property changes on automated tissue classification of brain structures using SPM12. Computational anatomy studies of ageing and neurodegeneration should acknowledge these effects, particularly when inferring about underlying pathophysiology from regional cortex and basal ganglia volume changes.

A Novel SLC6A8 Mutation in a Large Family with X-Linked Intellectual Disability: Clinical and Proton Magnetic Resonance Spectroscopy Data of Both Hemizygous Males and Heterozygous Females

X-linked creatine transport (CRTR) deficiency, caused by mutations in the SLC6A8 gene, leads to intellectual disability, speech delay, epilepsy, and autistic behavior in hemizygous males. Additional diagnostic features are depleted brain creatine levels and increased creatine/creatinine ratio (cr/crn) in urine. In heterozygous females the phenotype is highly variable and diagnostic hallmarks might be inconclusive. This survey aims to explore the intrafamilial variability of clinical and brain proton Magnetic Resonance Spectroscopy (MRS) findings in males and females with CRTR deficiency. X-chromosome exome sequencing identified a novel missense mutation in the SLC6A8 gene (p.G351R) in a large family with X-linked intellectual disability. Detailed clinical investigations including neuropsychological assessment, measurement of in vivo brain creatine concentrations using quantitative MRS, and analyses of creatine metabolites in urine were performed in five clinically affected family members including three heterozygous females and one hemizygous male confirming the diagnosis of CRTR deficiency. The severe phenotype of the hemizygous male was accompanied by most distinct aberrations of brain creatine concentrations (-83% in gray and -79% in white matter of age-matched normal controls) and urinary creatine/creatinine ratio. In contrast, the heterozygous females showed varying albeit generally milder phenotypes with less severe brain creatine (-50% to -33% in gray and -45% to none in white matter) and biochemical urine abnormalities. An intrafamilial correlation between female phenotype, brain creatine depletion, and urinary creatine abnormalities was observed. The combination of powerful new technologies like exome-next-generation sequencing with thorough systematic evaluation of patients will further expand the clinical spectrum of neurometabolic diseases.

Predicting nonsentinel lymph node metastases using established nomograms among patients with breast cancer after primary systemic therapy (PST): The transSENTINA substudy

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Background: Recent studies such as the SENTINA trial suggest that performing SLNB in patients with a cN1 status before but converting to a ycN0 status through PST result more often in a false-negative evaluation of LN status compared to SLNB at primary surgery. Therefore, there is a need to predict non-SLN status after PST and tailor axillary staging procedures. We investigated the accuracy of established nomograms to predict non-SLN metastases at primary surgery in patients after PST. Methods: The SENTINA trial is a 4-arm prospective multicenter cohort study evaluating an algorithm for the timing of a standardized SLNB in patients undergoing PST. 1,737 pts. from 104 institutions were categorized into four treatment arms according to the clinical axillary staging (including ultrasound examination) before and after chemotherapy. Patients in arm C with a cN1 status prior to PST converting to a ycN0 status but found to have a histologically positive SLN after PST were included. Several published nomograms predicting non-SLN status in patients with a positive SLN at primary surgery were applied (including the MSKCC-, Mayo-, Cambridge-, and Stanford-Nomogram, MDA-Score and Tenon-Score) and Area-under-the-Curve-(AUC)-values were calculated. Results:This subgroup comprised 592 patients. Among these, 74 patients had a positive SLN after PST and had all available data to run the nomograms. AUC-values were: MSKCC: 82.3 (95% confidence interval (95%CI) 72.6-91.9), Mayo: 71.8 (95%CI 60.1-83.5), Cambridge: 71.5 (95%CI 59.7-83.2), Stanford 70.6 (95%CI 59.7-83.2), MDA 70.7 (95%CI 59.0-82.5), and Tenon 73.1 (61.5-84.7). Conclusions: Analysis of the above nomograms in the post-neoadjuvant setting yielded AUC values comparable to those in the setting of primary surgery. Our results suggest that nomograms predicting non-SLN status in the setting of primary surgery (and particularly the MSKCC nomogram) may be used to avoid full axillary dissection in patients after PST.

Sentinel-lymph-node biopsy in patients with breast cancer before and after neoadjuvant chemotherapy (SENTINA): a prospective, multicentre cohort study

BACKGROUND

The optimum timing of sentinel-lymph-node biopsy for breast cancer patients treated with neoadjuvant chemotherapy is uncertain. The SENTINA (SENTinel NeoAdjuvant) study was designed to evaluate a specific algorithm for timing of a standardised sentinel-lymph-node biopsy procedure in patients who undergo neoadjuvant chemotherapy.

METHODS

SENTINA is a four-arm, prospective, multicentre cohort study undertaken at 103 institutions in Germany and Austria. Women with breast cancer who were scheduled for neoadjuvant chemotherapy were enrolled into the study. Patients with clinically node-negative disease (cN0) underwent sentinel-lymph-node biopsy before neoadjuvant chemotherapy (arm A). If the sentinel node was positive (pN1), a second sentinel-lymph-node biopsy procedure was done after neoadjuvant chemotherapy (arm B). Women with clinically node-positive disease (cN+) received neoadjuvant chemotherapy. Those who converted to clinically node-negative disease after chemotherapy (ycN0; arm C) were treated with sentinel-lymph-node biopsy and axillary dissection. Only patients whose clinical nodal status remained positive (ycN1) underwent axillary dissection without sentinel-lymph-node biopsy (arm D). The primary endpoint was accuracy (false-negative rate) of sentinel-lymph-node biopsy after neoadjuvant chemotherapy for patients who converted from cN1 to ycN0 disease during neoadjuvant chemotherapy (arm C). Secondary endpoints included comparison of the detection rate of sentinel-lymph-node biopsy before and after neoadjuvant chemotherapy, and also the false-negative rate and detection rate of sentinel-lymph-node biopsy after removal of the sentinel lymph node. Analyses were done according to treatment received (per protocol).

FINDINGS

Of 1737 patients who received treatment, 1022 women underwent sentinel-lymph-node biopsy before neoadjuvant chemotherapy (arms A and B), with a detection rate of 99.1% (95% CI 98.3-99.6; 1013 of 1022). In patients who converted after neoadjuvant chemotherapy from cN+ to ycN0 (arm C), the detection rate was 80.1% (95% CI 76.6-83.2; 474 of 592) and false-negative rate was 14.2% (95% CI 9.9-19.4; 32 of 226). The false-negative rate was 24.3% (17 of 70) for women who had one node removed and 18.5% (10 of 54) for those who had two sentinel nodes removed (arm C). In patients who had a second sentinel-lymph-node biopsy procedure after neoadjuvant chemotherapy (arm B), the detection rate was 60.8% (95% CI 55.6-65.9; 219 of 360) and the false-negative rate was 51.6% (95% CI 38.7-64.2; 33 of 64).

INTERPRETATION

Sentinel-lymph-node biopsy is a reliable diagnostic method before neoadjuvant chemotherapy. After systemic treatment or early sentinel-lymph-node biopsy, the procedure has a lower detection rate and a higher false-negative rate compared with sentinel-lymph-node biopsy done before neoadjuvant chemotherapy. These limitations should be considered if biopsy is planned after neoadjuvant chemotherapy.

FUNDING

Brustkrebs Deutschland, German Society for Senology, German Breast Group.

Increased growth of colorectal liver metastasis following partial hepatectomy

Nearly 50 % of colorectal cancer (CRC) patients develop liver metastases with liver resection being the only option to cure patients. Residual micrometastases or circulating tumor cells are considered a cause of tumor relapse. This work investigates the influence of partial hepatectomy (PH) on the growth and molecular composition of CRC liver metastasis in a syngeneic rat model. One million CC531 colorectal tumor cells were implanted via the portal vein in WAG/Rij rats followed by a 30 % PH a day later. Control groups either received tumor cells followed by a sham-operation or were injected with a buffer solution followed by PH. Animals were examined with magnetic resonance imaging (MRI) and liver tissues were processed for immunolabeling and PCR analysis. One-third PH was associated with an almost threefold increase in relative tumor mass (MRI volumetry: 2.8-fold and transcript levels of CD44: 2.3-fold). Expression of molecular markers for invasiveness and aggressiveness (CD49f, CXCR4, Axin2 and c-met) was increased following PH, however with no significant differences when referring to the relative expression levels (relating to tumor mass). Liver metastases demonstrated a significantly higher proliferation rate (Ki67) 2 weeks following PH and cell divisions also increased in the surrounding liver tissue. Following PH, the stimulated growth of metastases clearly exceeded the compensation in liver volume with long-lasting proliferative effects. However, the distinct tumor composition was not influenced by liver regeneration. Future investigations should focus on the inhibition of cell cycle (i.e. systemic therapy strategies, irradiation) to hinder liver regeneration and therefore restrain tumor growth.

Differentiation of typical and atypical Parkinson syndromes by quantitative MR imaging

BACKGROUND AND PURPOSE

The differential diagnosis of Parkinson syndromes remains a major challenge. Quantitative MR imaging can aid in this classification, but it is unclear which of the proposed techniques is best suited for this task. We, therefore, conducted a head-to-head study with different quantitative MR imaging measurements in patients with IPS, MSA-type Parkinson, PSP, and healthy elderly controls.

MATERIALS AND METHODS

Thirty-one patients and 13 controls underwent a comprehensive quantitative MR imaging protocol including R2*-, R2- and R1-mapping, magnetization transfer, and DTI with manual region-of-interest measurements in basal ganglia regions. Group differences were assessed with a post hoc ANOVA with a Bonferroni error correction and an ROC.

RESULTS

The best separation of MSA from IPS in patients and controls could be achieved with R2*-mapping in the PU, with an ROC AUC of ≤0.96, resulting in a sensitivity of 77.8% (with a specificity 100%). MD was increased in patients with PSP compared with controls and to a lesser extent compared with those with IPS and MSA in the SN.

CONCLUSIONS

Among the applied quantitative MR imaging methods, R2*-mapping seems to have the best predictive power to separate patients with MSA from those with IPS, and DTI for identifying PSP.