Abstract P1-05-30: Concordance of preoperative breast MRI finding with definitive postoperative pathology report, after neoadjuvant systemic treatment in patients with breast cancer

Neoadjuvant, i.e. preoperative, systemic antineoplastic treatment (NAT), in patients with breast cancer enables in vivo monitoring of tumor response to applied therapy, tailoring treatment in real –time accordingly, sparing surgical procedures, better quality of life for patients and implies better patient survival for particular patient, if a pathological complete response (pCR) to treatment is achieved. Use of MRI in monitoring response to NAT has shown in various studies sensitivity and specificity of at least 70% in the detection of residual disease, with a high positive and negative predictive value. Studies have shown higher accuracy in predicting pCR in HER2 positive tumors, and a higher rate of false negative results in HER2 negative tumors. Here we report findings of our pilot project where we tested the accuracy of the MRI, and the concordance of preoperative MRI findings after NAT, with the definitive pathology report after the surgery was performed, in breast cancer patients with different disease biology, in the real clinical practice. The focused pathological supstrate was the primary tumor in the breast. For the simplicity of this pilot analysis, we did not include here the status of the axilla, which will be included in our larger analysis pending. We performed our analysis on a cohort of 200 breast cancer patients who underwent NAT, in our institution, University Hospital for Tumors, in Zagreb, Croatia. Median age of the analyzed patient cohort was 62 years. The representation of individual breast cancer intrinsic subtype surrogates was as follows: HER2 nonluminal tumor 23.5% (47/200), triple negative breast cancer 21.5% (43/200), luminal HER2 positive 22.5% (45/200) and luminal HER2 negative 32.5% (65/200). According to MRI of the primary tumor in the breast, radiological complete response (rCR) to NAT was achieved in 46.5% (93/200) of patients, and the finding of residual tumor was described in 53.5% (107/200) of patients. Postoperatively, pathology report of the primary breast tumor showed pCR in 29% (58/200) of patients, and residual disease in 71% (142/200) of cases. The overall concordance of MR and pathology reports was 62.4% in the assessment of complete response, and 75.35% in the assessment of residual disease. Analyzed according to subgroups, results are as follows: in the cohort of patients with HER2 nonluminal tumors, concordance of MRI and pathology report in the assessment of complete response was 88%, while for residual disease concordance was 70%; in the cohort with triple-negative breast cancer patients, concordance of MRI and pathology report in the assessment of complete response was 83%, and residual disease 87.8%; in the group with luminal HER2-positive breast cancer concordance of MRI and pathology report in assessing complete response, as well as residual disease, was 97%; while in the group with luminal HER2-negative breast cancer, concordance of MRI and pathology report findings in assessing complete response was only 50.5%, and residual disease 77%. Results of our analysis showed relatively high overall concordance between MRI and pathology findings, which is in line with results of large studies worldwide and confirms MRI as a good method in monitoring response to NAT in breast cancer patients. By subgroup analysis, patients with luminal HER2-negative tumors are distinguished. This group has the lowest prevalence of complete response overall, as well as the lowest concordance of MRI and pathology report findings in the detection of these cases. This confirms the weaker response of this type of tumor to neoadjuvant treatment, but also indicates the need for additional caution when analyzing MRI findings in these patients, as well as for considering additional diagnostic arsenal, complementing the standardly – utilised MRI.

Citation Format: Ana Tecic Vuger, Melita Peric Balja, Petra Jaksic, Petra Linaric, Mirjana Pavlovic Mavic, Ljubica Vazdar, Robert Separovic. Concordance of preoperative breast MRI finding with definitive postoperative pathology report, after neoadjuvant systemic treatment in patients with breast cancer [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P1-05-30.

Anthracyclines in the treatment of early breast cancer friend or foe?

Standard chemotherapy for early breast cancer consists generally of an anthracycline – taxane - based regimen, preferably in sequence. Anthracyclines are among the most active cytotoxic drugs against breast cancer. Nevertheless, benefits attained by the use of the more potent anthracycline schedules must be balanced against increased short – and long – term toxicity, and treatment options must be individualized for each patient. Authors review available data regarding anthracycline efficacy and toxicity in the early breast cancer setting and the potential directions for future research.

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Anthracyclines are one of the most effective drugs against breast cancer.

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Anthracyclines and taxanes for early breast cancer reduce mortality.

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Anthracyclines raise some concerns about cardiotoxicity and secondary leukemia.

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Controversy remains regarding risk/benefit for the use of adjuvant anthracyclines.

Impact of cancer diagnosis, stage, and systemic therapies on immunogenicity after COVID-19 vaccination in patients with cancer: A systematic review and meta-analysis

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Background: Patients (pts) with cancer are at increased risk of severe COVID-19. Both underlying malignancy and anti-cancer treatments influence the immune system, potentially impacting the level of vaccine protection achieved. Methods: A systematic literature search of PubMed, Embase, CENTRAL and conference proceedings (ASCO annual meetings and ESMO congress) up to 28/09/21, was conducted to identify studies reporting anti-SARS-CoV-2 spike protein immunoglobulin G seroconversion rates (SR) at any time point after complete COVID-19 immunization (mRNA- or adenoviral-based vaccines) in cancer pts. Complete immunization was defined as 1 dose of JNJ-78436735 vaccine or 2 doses of BNT162b2, mRNA-1273 or ChAdOx1 nCoV-19 vaccines. Subgroup analyses were performed to examine the impact of cancer diagnosis, disease stage, and anticancer therapies on the SR. Overall effects were pooled using random-effects models and reported as pooled SR with 95% confidence intervals (CI). Results: Of 1,548 identified records, 64 studies were included in this analysis reporting data from 10,511 subjects. The Table shows the SR in the overall population and specific subgroups. In pts with solid malignancies (SM), disease stage and primary site did not significantly impact the SR. In pts with hematologic malignancies (HM), SR were significantly lower in pts with chronic lymphocytic leukemia (CLL) and non-Hodgkin lymphoma (NHL) compared to acute lymphoblastic leukemia (ALL), Hodgkin lymphoma (HL), and multiple myeloma (MM). Concerning the impact of cancer therapies on SR, pts with SM undergoing chemotherapy had numerically lower SR (N = 1,234, SR 87%, CI 81-92) compared to those treated with immune checkpoint inhibitors (N = 574, SR 94%, CI 88-97) or endocrine therapy (N = 326, SR 94%, CI 86-97) with or without another targeted therapy. Pts with HM treated with anti-CD20 therapy (within the last 12 months: N = 360, SR 7%, CI 2-20; or more than 12m: N = 175, SR 59%, CI 35-80), immune-modulating agents (BTK or BCL2 inhibitors) (N = 462, SR 47%, CI 32-64%) or other immunotherapies (anti-CD19/CART or anti-CD38) (N = 293, SR 37%, CI 23-53) had lower SR compared to pts treated with autologous (N = 353, SR 77%, CI 67-85) or allogenic stem cell transplantation (N = 509, SR 77%, CI 68-84). Conclusions: SR varies between cancer types and anticancer therapies with some cancer pts having low protection against COVID-19 even after complete vaccination. [Table: see text]

Demographic and laboratory determinants of humoral immune responses and impact of different anti-SARS-CoV-2 vaccine platforms in patients with cancer: A systematic review and meta-analysis

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Background: Patients (pts) with cancer have increased mortality from COVID-19 and their vaccination is crucial to prevent severe infection. We aimed to identify demographic and laboratory determinants of humoral immune responses to COVID-19 vaccination in pts with cancer and investigate differences in responses based on the vaccine platform. Methods: We searched for records in PubMed, Embase, and CENTRAL up to 28/09/21, as well as conference proceedings from ASCO and ESMO 2021. We included studies of pts ≥16 yr with a cancer diagnosis, who were vaccinated against SARS-CoV-2. Studies were excluded if ≥10% of the participants had other causes of immunosuppression or baseline anti-SARS-CoV-2 spike protein antibodies (Ab)/previous COVID-19 (PROSPERO ID: CRD42021282338). For this subgroup analysis of studies that reported a proportion of pts with cancer and positive Ab titers at any timepoint following complete vaccination, a random-effects model was used to estimate the humoral response rate (HRR) with 95% confidence intervals (CI). Results: We included 64 records, reporting data from 10,511 cancer pts. The HRR in the overall population and by subgroup are shown in Table. Elder patients with hematologic cancers (59%, CI 47-70%, N = 667) and patients with lymphopenia (50%, CI 25-75%, N = 111) or hypogammaglobulinemia (36%, CI 19-57%, N=226) were the subgroups with lower HRR. Male (77%, CI 69-84%, N = 2,659) and Asian (84%, CI 54-96%, N = 37) pts showed a trend to lower HRR when compared with females and other races, respectively. Pts vaccinated with mRNA vaccine platforms (79%, CI 74-83%, N = 9,404) had numerically higher HRR than those receiving the adenovirus vaccines (28%, CI 19-40%, N = 74). Conclusions: This study highlights demographic and laboratory determinants of weaker immune responses to SARS-CoV-2 vaccination, permitting better identification of more vulnerable pts. Despite the small number of pts included receiving adenovirus vaccines, these data also suggest prioritizing mRNA platform vaccination in pts with cancer. [Table: see text]

Abstract PS6-56: Clinical validity of compartmental analysis of tumor-infiltrating lymphocytes (TIL) in triple-negative breast cancer (TNBC) - The key is in spatial morphology?

INTRODUCTIONAnalyzes reported to date on TIL in TNBC have evaluated mostly stromal (sTIL) and possibly intratumoral TIL (iTIL), but none evaluated TIL spatially, separately in compartments of central tumor (CT) and invasive margin (IM). Also, none evaluated connection between TIL and other clinicopathological factors.

METHODSWe retrospectively analyzed consecutive sample of 152 early TNBC patients treated at our institution 2009-2012. TIL were assessed morphologically, by hematoxylin - eosin (HE), using standard formalin - fixed - paraffin - embedded (FFPE) samples, according to recommendation of International Working Group for Evaluation of TIL, both sTIL and iTIL, spatially, in compartments of CT and IM. Available clinicopathological variables were analyzed, and correlations of all paramethers were calculated.

RESULTSMorphological analysis of TIL spatially by compartments showed as follows: median overall sTIL content was 19%, iTIL 5%, TIL in CT 5%, TIL at IM 18%, sTIL in CT 5%, iTIL in CT 1%, sTIL at IM 30%, and iTIL at IM 5%. Intermediate or high TIL content, defined as ≥10% was present in 48% cases of sTIL in CT, 23% of iTIL in CT, 86% of sTIL at IM, and in 47% of iTIL at IM cases. Quarter of patients had TIL>50% in any of four compartments. There was statistically significant positive correlation between sTIL in CT and age and menopausal status, and also tumor size (T), but w/out correlation to histologic subtype, nodal (N) status, grade, and Ki67; iTIL in CT were statistically significantly positively correlated to histologic subtype (precisely to NOS subtype), but negatively to age and menopausal status, exactly opposite to sTIL in this section, and w/out correlation to other tumor characteristics, such as T, N, grade or Ki67; sTIL on IM, as well as iTIL on IM, showed statistically significant correlation to grade and Ki67, and no correlation to age and menopausal status.

DISCUSSIONSection analysis reveals higher density of TIL content at IM, which directs attention towards this neglected tumoral compartment and it's possible role. It also shows, although in small numbers, that possibly iTIL, especially those at IM, could actually not only, as thought so far, serve as ,,satellites“ to sTIL, but an entirely autonomous, and even opposite biomarker. Moreover, all that could be concluded from just a simple and cheap HE morphological analysis of standard tumor specimen.

Citation Format: Ana Tecic Vuger, Robert Separovic, Ljubica Vazdar, Mirjana Pavlovic, Sanda Sitic, Ingrid Belac-Lovasic, Damir Vrbanec. Clinical validity of compartmental analysis of tumor-infiltrating lymphocytes (TIL) in triple-negative breast cancer (TNBC) - The key is in spatial morphology? [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 PS6-56.

Prognostic value of tumor: Infiltrating lymphocytes and androgen receptors correlation in triple negative breast cancer

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Background: Little is known about correlation of tumor infiltrating lymphocytes (TIL) and androgen receptors (AR) and their joint effect on early triple-negative breast cancer (TNBC) prognosis. Analyzes to date evaluated mostly stromal TIL (sTIL) and intratumoral (iTIL), but not separately in central tumor (CT) and invasive margin (IM). Methods: We retrospectively analyzed consecutive sample of 152 early TNBC patients treated at our institution 2009-2012. TIL and AR were assessed using standard FFPE samples, TIL according to International Working Group for Evaluation of TIL recommendation, sTIL and iTIL in CT and IM, and AR by immunohistochemistry. Results: Median age was 58, 84% NOS, median T 2.2cm, 41% N+, 22%, 59% and 19% in stage I, II and III, respectively. Radical mastectomy was performed in 39%, adjuvant chemotherapy in 88% and radiotherapy in 74% of patients. Positive AR defined as ≥1% nuclear-stained cells, were expressed in 31%, and AR≥10% in 26% of patients. Median TIL content was: sTIL 19%, iTIL 5%, TIL in CT 5%, at IM 18%, sTIL in CT (CTs) 5%, iTIL in CT (CTi) 1%, sTIL at IM (IMs) 30%, and iTIL at IM (IMi) 5%. Prevalence of intermediate or high TIL content, defined as ≥10% was: CTs in 48%, CTi in 23%, IMs in 86%, and IMi in 47% of cases. In bivariable analysis all TIL indicators were significantly associated with longer OS, while AR was not. After adjustment for potential confounders using Cox proportional hazard regression, significant predictors of OS were sTIL (p0.007), IM TIL (p0.002), IMs (p0.001), and IMi (p0.030). In all cases higher TIL content was associated with longer OS. Although AR was not significant predictor of OS, it's interactions with TIL IMs and IMi was. There was no significant difference in OS between patients with high IMs and low IMs and AR0, but those with high IMs and AR≥1 had HR0.22 (p0.045) for death compared to patients with low IMs and AR0. Also, no difference for high IMi and low IMi and AR0, but patients with high IMi and AR≥1 had HR0.10 (p0.028) for death compared to patients with low IMi and AR0. Conclusions: Section analysis reveals frequent intermediate to high density and statistically significant prognostic impact of TIL on IM. That directs question towards role of different tumor compartments. Furthermore, combination of high expression of IMs and IMi with AR≥1 appears to be associated with longer OS than in patients with high IMs and IMi but with AR0. The correlations between AR and all TIL studied are extremely small, indicating their independence, but if so, their interaction in impact on OS is particularly interesting.

Searching for a link between Ki-67 values and HER2 absence in 297 patients with triple-negative breast cancer

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Background: Based on the report that in ER- invasive breast cancer (IBC) patients, the absence of HER2 might be linked to their Ki-67 values ( Kurbel et al. BMC Cancer 2017;17:231), this relation was searched in 297 consecutive IBC patients with triple negative tumors, treated at two Croatian hospitals. Methods: All 297 patients had ER and PgR negative IBC, The HER2 expression was IHC absent in 211 pts.; IHC 1+ in 62 pts.: IHC 2+ & ISH negative in 24 pts. Based on the cited reference that the Expectation maximization clustering (EM) of the pooled IBC Ki-67 values detects three clusters, regardless of the tumor type, the same approach was used. Differences in the distribution of HER2 values were tested by the χ2 test. Results: Three EM clusters were detected among the pooled Ki67 values: LMA (low mitotic activity) cluster: 109 cases with Ki-67 < 44%; IMA (intermediate mitotic activity) cluster: 96 cases, Ki-67 from 44 to 70% and HMA (high mitotic activity) cluster: 92 cases, Ki-67 > 70%. Beside the Ki-67, distribution of HER2 values was dependent on the age (Chi-square: 25.0309, df = 12, p = 0.014677), as shown here: In patients younger than 46, the HMA cluster was 32% larger than expected. Out of 29 HMA pts, 24 had HER2 absent tumors (53% more than expected). In patients aged 46 to 55, the IMA cluster was 27% larger than expected and out of 30 IMA, 24 had HER2 absent tumors (43% more than expected). In patients older than 55, the LMA cluster was 21% larger than expected, due to more patients with tumors positive for HER2. Out of 68 LMA pts., 22 pts. had tumors with HER2 expression (1+/2+), 40% more than expected. Conclusions: HER2 absent triple negative IBCs might be biologically different from the triple negative and HER2 1+/2+ tumors. The former were linked to pts younger than 55 and Ki-67 values > 43%. The latter showed opposite affinities, age above 55 and Ki-67 < 44%. Based on this, the absence of HER2 in triple negative IBC seems a valid target for future research.[Table: see text]