Changes in Invasive Breast Carcinomas after Neoadjuvant Chemotherapy Can Influence Adjuvant Therapeutic Decisions

PURPOSE

Neoadjuvant chemotherapy (NACT) can change invasive breast carcinomas (IBC) and influence the patients' overall survival time (OS). We aimed to identify IBC changes after NACT and their association with OS.

MATERIALS AND METHODS

IBC data in pre- and post-NACT samples of 86 patients were evaluated and associated with OS.

RESULTS

Post-NACT tumors changed nuclear pleomorphism score (p=0.025); mitotic count (p=0.002); % of tumor-infiltrating inflammatory cells (p=0.016); presence of in situ carcinoma (p=0.001) and lymphovascular invasion (LVI; p=0.002); expression of estrogen (p=0.003), progesterone receptors (PR; p=0.019), and Ki67 (p=0.003). Immunohistochemical (IHC) profile changed in 26 tumors (30.2%, p=0.050). Higher risk of death was significatively associated with initial tumor histological grade III (hazard ratio [HR], 2.94), high nuclear pleomorphism (HR, 2.53), high Ki67 index (HR, 2.47), post-NACT presence of LVI (HR, 1.90), luminal B-like profile (HR, 2.58), pre- (HR, 2.26) and post-NACT intermediate mitotic count (HR, 2.12), pre- (HR, 4.45) and post-NACT triple-negative IHC profile (HR, 4.52). On the other hand, lower risk of death was significative associated with pre- (HR, 0.35) and post-NACT (HR, 0.39) estrogen receptor-positive, and pre- (HR, 0.37) and post-NACT (HR, 0.57) PR-positive. Changes in IHC profile were associated with longer OS (p=0.050). In multivariate analysis, pre-NACT grade III tumors and pre-NACT and post-NACT triple negative IHC profile proved to be independent factors for shorter OS.

CONCLUSION

NACT can change tumor characteristics and biomarkers and impact on OS; therefore, they should be reassessed on residual samples to improve therapeutic decisions.

Synergistic Effects of Metformin and Trastuzumab on HER2 Positive Gastroesophageal Adenocarcinoma Cells In Vitro and In Vivo

The incidence of HER2 amplification in advanced gastroesophageal adenocarcinoma (GC) reportedly ranges between 10% and 20%, depending on the population studied and the geographical region. Trastuzumab (Tmab) is the standard treatment for GCs with HER2 amplification. Metformin, a widely used antidiabetic drug, is an activator of AMP kinase that can affect the mTOR signaling pathway. The following GC cells were evaluated: HER2+ NCI-N87, YCC-19, YCC-38, OE19, OE33, and HER2- AGS. The effects of Tmab and metformin on these cell lines were assessed as single agents and in combination using cell viability assays, Western blotting, and xenograft models. Metformin induced phosphorylation of AMP kinase in all tested GC cells and dephosphorylation of mTOR in Tmab-sensitive GC cells. We observed that treatment with Tmab in combination with metformin induced a significant decrease in the number of colonies formed on soft agar by N87, YCC-19, YCC-38, and OE19 cells (88%, 95%, 73%, and 98%, respectively), in comparison to the number formed by control cells or cells in the single-treatment groups. No growth inhibition was detected in OE33 cells treated with Tmab alone. Combination with metformin resulted in decreased phosphorylation of HER2 and its downstream targets, AKT and ERK, in Tmab-sensitive HER2+ cells. Phospho-receptor tyrosine kinase (RTK) arrays were used to profile the phospho-proteome, which demonstrated a synergistic decrease in phosphorylation of EGFR, HER2, and HER3. Furthermore, the combination of Tmab and metformin exhibited enhanced antitumor effects in a xenograft model. Collectively, these data suggest that Tmab and metformin act synergistically in HER2+ GC cells. Since metformin is widely used and relatively non-toxic, its addition to the therapeutic regimen along with Tmab could enhance the clinical efficacy in patients with HER2+ GC.

The tumor immune contexture of salivary duct carcinoma

BACKGROUND

Salivary duct carcinoma (SDC) is a rare and aggressive malignancy. Recently, biomarker studies found promising targetable alterations. In this study, we provide a descriptive analysis of tumor and immune biomarkers and survival associations.

METHODS

We extracted clinical data and performed immunohistochemistry for AR, AR-V7, HER-2, PD-L1, LAG-3, and tumor-infiltrating immune cells.

RESULTS

We included 17 patients. Age ranged from 42 to 85 years old; HER-2 was overexpressed or amplified in 65%. AR was positive in 88% of patients, while AR-V7 was positive in 13% by IHC. We found low scores of immune infiltration and a PD-L1 expression in 53%. We found no clinically significant association between biomarkers and survival outcomes.

CONCLUSION

In this small series of SDC, biomarkers do not seem to correlate with disease biology, although they provide additional treatment options. SDC may harbor a different immune profile compared to other subtypes, with an indication of T-cell dysfunction.

Neoadjuvant targeted therapy for apocrine carcinoma of the breast: A case report

BACKGROUND

Apocrine carcinoma of the breast is a special type of invasive ductal carcinoma of the breast that is rare in clinical practice. Neoadjuvant therapy, especially neoadjuvant targeted therapy, has rarely been reported for apocrine carcinoma of the breast.

CASE SUMMARY

A 63-year-old woman presented with apocrine carcinoma of the left breast underwent core needle biopsy. The patient was diagnosed with apocrine carcinoma by immunohistochemical staining and negative hormone status (estrogen receptor and progesterone receptor) but showed overexpression of human epidermal factor receptor 2 (HER-2). Moreover, positive expression of androgen receptor (approximately 60%) and gross cystic disease fluid protein 15 was observed. The patient was treated with neoadjuvant targeted therapy consisting of the TCH regimen (docetaxel, carboplatin area under curve 6 and trastuzumab) every 21 d. The mass in the left breast was significantly reduced, and pain in the breast and left upper arm also improved.

CONCLUSION

HER-2 positive apocrine carcinoma of the breast can be improved by neoadjuvant chemotherapy combined with targeted therapy.

MRI-based machine learning radiomics can predict HER2 expression level and pathologic response after neoadjuvant therapy in HER2 overexpressing breast cancer

Background

To use clinical and MRI radiomic features coupled with machine learning to assess HER2 expression level and predict pathologic response (pCR) in HER2 overexpressing breast cancer patients receiving neoadjuvant chemotherapy (NAC).

Methods

This retrospective study included 311 patients. pCR was defined as no residual invasive carcinoma in the breast or axillary lymph nodes (ypT0/isN0). Radiomics/statistical analysis was performed using MATLAB and CERR software. After ROC and correlation analysis, selected radiomics parameters were advanced to machine learning modelling alongside clinical MRI-based parameters (lesion type, multifocality, size, nodal status). For predicting pCR, the data was split into a training and test set (80:20).

Findings

The overall pCR rate was 60.5% (188/311). The final model to predict HER2 heterogeneity utilised three MRI parameters (two clinical, one radiomic) for a sensitivity of 99.3% (277/279), specificity of 81.3% (26/32), and diagnostic accuracy of 97.4% (303/311). The final model to predict pCR included six MRI parameters (two clinical, four radiomic) for a sensitivity of 86.5% (32/37), specificity of 80.0% (20/25), and diagnostic accuracy of 83.9% (52/62) (test set); these results were independent of age and ER status, and outperformed the best model developed using clinical parameters only (p=0.029, comparison of proportion Chi-squared test).

Interpretation

The machine learning models, including both clinical and radiomics MRI features, can be used to assess HER2 expression level and can predict pCR after NAC in HER2 overexpressing breast cancer patients.

Funding

NIH/NCI (P30CA008748), Susan G. Komen Foundation, Breast Cancer Research Foundation, Spanish Foundation Alfonso Martin Escudero, European School of Radiology.

Increased assessment of HER2 in metastatic gastroesophageal cancer patients: a nationwide population-based cohort study

BACKGROUND

Addition of trastuzumab to first-line palliative chemotherapy in gastroesophageal cancer patients with HER2 overexpression has shown to improve survival. Real-world data on HER2 assessment and administration of trastuzumab are lacking. The aim of this study was to assess HER2 testing, trastuzumab administration, and overall survival (OS) in a nationwide cohort of metastatic gastroesophageal cancer patients.

METHODS

Data of patients with synchronous metastatic gastroesophageal adenocarcinoma diagnosed in 2010-2016 that received palliative systemic treatment (n = 2846) were collected from the Netherlands Cancer Registry and Dutch Pathology Registry. The ToGA trial criteria were used to determine HER2 overexpression. Proportions of HER2 tested patients were analyzed between hospital volume categories using Chi-square tests, and over time using trend analysis. OS was tested using the Kaplan Meier method with log rank test.

RESULTS

HER2 assessment increased annually, from 18% in 2010 to 88% in 2016 (P < 0.01). Median OS increased from 6.9 (2010-2013) to 7.9 months (2014-2016; P < 0.05). Between the hospitals, the proportion of tested patients varied between 29-100%, and was higher in high-volume hospitals (P < 0.01). Overall, 77% of the HER2 positive patients received trastuzumab. Median OS was higher in patients with positive (8.8 months) and negative (7.4 months) HER2 status, compared to non-tested patients (5.6 months; P < 0.05).

CONCLUSION

Increased determination of HER2 and administration of trastuzumab have changed daily practice management of metastatic gastroesophageal cancer patients receiving palliative systemic therapy, and possibly contributed to their improved survival. Further increase in awareness of HER2 testing and trastuzumab administration may improve quality of care and patient outcomes.

Shed HER2 surrogacy evaluation in primary breast cancer patients: a study assessing tumor tissue HER2 expression at both extracellular and intracellular levels

The aim of the present study was to investigate serum HER2 extracellular domain (ECD) as a putative surrogate marker of the shedding phenomenon of HER2 receptor from the tumor tissue of primary breast cancer (BC) patients. A pilot retrospective study was conducted on 100 matched serum and tissue samples from patients with node-positive primary BC, stage II/III. Analysis of association and concordance between serum HER2 ECD levels (measured by chemiluminescence immunoassay) and the expression in matched tumor tissue of HER2 ECD and intracellular receptor domain (ICD) (determined by immunohistochemistry) were performed. The median serum HER2 ECD level was 9.4 ng/ml and cutoff values were set at 15.2 ng/ml or 13.0 ng/ml. HER2 ICD and ECD were overexpressed in tumor tissue of 19.8% and 6.9% of patients, respectively. Statistically significant associations were found between serum HER2 ECD levels and tissue expression of both HER2 ICD and ECD (p < .001; Fisher analysis). Moreover, strong concordances were found between serum HER2 ECD levels and tissue expression of HER2 ICD or ECD (cutoff 15.2 ng/ml: 80 and 92.5%, respectively). Our findings support a role for serum HER2 ECD as a surrogate marker of tissue HER2 status in primary BC, both for HER2 ICD or ECD expression.

Clinical Differences in Triple-Positive Operable Breast Cancer Subtypes in Korean Patients: An Analysis of Korean Breast Cancer Registry Data

Purpose

Triple-positive breast cancer is defined by estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2) positivity. Several systemic breast cancer therapies target hormonal and HER2 responsiveness. We compared clinical outcomes of triple-positive disease with those of HER2-enriched and luminal HER2-negative disease and investigated the clinical efficacy of anti-HER2 therapy for triple-positive disease.

Methods

We retrospectively compared overall and recurrence-free survival among cases included in the Korean Breast Cancer Society (KBCS) and Seoul St. Mary's Hospital breast cancer registries and the therapeutic efficacy of trastuzumab for triple-positive and HER2-enriched cases.

Results

KBCS registry data (2006–2010; median follow-up, 76 months) indicated that patients with triple-positive breast cancer had intermediate survival between those with luminal A and HER2-enriched subtypes (p<0.001). Trastuzumab did not improve overall survival among patients with triple-positive breast cancer (p=0.899) in contrast to the HER2-enriched subtype (p=0.018). Seoul St. Mary's Hospital registry data indicated similar recurrence-free survival outcomes (p<0.001) and a lack of improvement with trastuzumab among patients with triple-positive breast cancer (median follow-up, 33 months; p=0.800). Multivariate analysis revealed that patients with triple-positive breast cancer had better overall survival than those with HER2-enriched disease and similar survival as those with the luminal A subtype (triple-positive: hazard ratio, 1.258, p=0.118; HER2-enriched: hazard ratio, 2.377, p<0.001).

Conclusion

Our findings showed that anti-HER2 therapy was less beneficial for treatment of triple-positive breast cancer than for HER2-enriched subtypes of breast cancer, and the triple-positive subtype had a distinct prognosis.

PIK3CA Mutations and Neoadjuvant Therapy Outcome in Patients with Human Epidermal Growth Factor Receptor 2-Positive Breast Cancer: A Sequential Analysis

Purpose

PIK3CA mutation is considered to be a possible cause for resistance to neoadjuvant chemotherapy (NAC) in human epidermal growth factor receptor 2 (HER2)-positive breast cancer. We investigated the association between PIK3CA mutations and the outcome of NAC in HER2-positive breast cancers.

Methods

A total of 100 HER2-positive breast cancer patients who had undergone NAC and surgery between 2004 and 2016 were examined. Mutation status was sequentially assessed in pre-NAC, post-NAC, and recurrent specimens taken from these patients.

Results

PIK3CA mutations were identified in the sequential specimens of 17 patients (17.0%). These 17 patients experienced shorter disease-free survival (DFS) than the rest of the patients (58.3 months vs. 119.3 months, p=0.020); however, there was no significant difference in pathologic complete response (pCR) and overall survival (OS) (pCR, 17.6% vs. 33.7%, p=0.191; OS, 84.5 months vs. 118.0 months, p=0.984). While there was no difference in pCR between the wild-type and mutant PIK3CA groups in pre-NAC specimens (25.0% vs. 31.8%, p=0.199), PIK3CA mutations correlated with lower pCR in post-NAC specimens (0.0% vs. 24.3%, p<0.001). Multivariate analysis revealed significantly worse DFS in the mutant PIK3CA group than in the wild-type group (hazard ratio, 3.540; 95% confidence interval, 1.001–12.589; p=0.050). Moreover, the DFS curves of the change of PIK3CA mutation status in sequential specimens were significantly different (p=0.016).

Conclusion

PIK3CA mutation in HER2-positive breast cancer was correlated with a lower pCR rate and shorter DFS. These results suggest that PIK3CA mutation is a prognostic marker for NAC in HER2-positive breast cancer, especially in post-NAC specimens.

FcrR3A-158 Polymorphism and Stromal Tumor-Infiltrating Lymphocytes and Survival among Patients with Metastatic HER2-Positive Breast Cancer Receiving Trastuzumab-Based Treatment

Purpose

The prognosis of human epidermal growth factor receptor 2 (HER2)-positive breast cancer has markedly improved since the introduction of trastuzumab. We aimed to evaluate the association between stromal tumor-infiltrating lymphocyte (sTIL) or FcrR polymorphisms and survival among patients with metastatic HER2-positive breast cancer who were treated with trastuzumab.

Methods

A total of 56 women with recurrent or metastatic HER2-positive breast cancer who received the trastuzumab-taxane combination as first-line treatment were included in this retrospective analysis. The single-step multiplex allele-specific real-time polymerase chain reaction technique was employed for FcrR3A genotyping. sTILs were identified via immunohistochemical analysis of surgical (n=34, 60.7%) or biopsy specimens of metastatic lesions (n=22, 39.3%).

Results

We classified patients based on the sTIL level (≤10% [n=44] or >10% [n=12]); high sTIL counts were more commonly observed in patients with hormone receptor-negative tumors than in those with hormone receptor-positive tumors (34.8% vs. 12.1%, p=0.02). There was a significant association between high sTIL levels and longer progression-free survival in comparison to low sTIL levels (median, 28.4 months vs. 16.8 months; p=0.03). With regard to the FcrR3A-158 genotype, patients were classified into the Phenylalanine/Phenylalanine group (23 patients, 41.1%), Phenylalanine/Valine group (23 patients, 41,1%), or Valine/Valine group (10 patients, 17.9%); these classifications were not associated with clinical outcomes.

Conclusion

High sTIL expression may be associated with better efficacy of trastuzumab-containing therapy in patients with metastatic HER2-positive breast cancer. However, this finding warrants further evaluation in the larger population.

FOXO1 Suppression is a Determinant of Acquired Lapatinib-Resistance in HER2-Positive Gastric Cancer Cells Through MET Upregulation

Purpose

Lapatinib is a candidate drug for treatment of trastuzumab-resistant, human epidermal growth factor receptor 2 (HER2)–positive gastric cancer (GC). Unfortunately, lapatinib resistance renders this drug ineffective. The present study investigated the implication of forkhead box O1 (FOXO1) signaling in the acquired lapatinib resistance in HER2-positive GC cells.

Materials and Methods

Lapatinib-resistant GC cell lines (SNU-216 LR2-8) were generated in vitro by chronic exposure of lapatinib-sensitive, HER2-positive SNU-216 cells to lapatinib. SNU-216 LR cells with FOXO1 overexpression were generated by stable transfection of a constitutively active FOXO1 mutant (FOXO1A3). HER2 and MET in SNU-216 LR cells were downregulated using RNA interference. The sensitivity of GC cells to lapatinib and/or cisplatin was determined by crystal violet assay. In addition, Western blot analysis, luciferase reporter assay and reverse transcription–polymerase chain reaction were performed.

Results

SNU-216 LR cells showed upregulations of HER2 and MET, but downregulation of FOXO1 compared to parental SNU-216 cells. FOXO1 overexpression in SNU-216 LR cells significantly suppressed resistance to lapatinib and/or cisplatin. In addition, FOXO1 negatively controlled HER2 and MET at the transcriptional level and was negatively controlled by these molecules at the post-transcriptional level. A positive crosstalk was shown between HER2 and MET, each of which increased resistance to lapatinib and/or cisplatin.

Conclusion

FOXO1 serves as an important linker between HER2 and MET signaling pathways through negative crosstalks and is a key regulator of the acquired lapatinib resistance in HER2-positive GC cells. These findings provide a rationale for establishing a novel treatment strategy to overcome lapatinib resistance in a subtype of GC patients.

Brain metastasis in human epidermal growth factor receptor 2-positive breast cancer: from biology to treatment

Overexpression of human epidermal growth factor receptor 2 (HER2) is found in about 20% of breast cancer patients. With treatment using trastuzumab, an anti-HER2 monoclonal antibody, systemic control is improved. Nonetheless, the incidence of brain metastasis does not be improved, rather seems to be increased in HER2-positive breast cancer. The mainstay treatment for brain metastases is radiotherapy. According to the number of metastatic lesions and performance status of patients, radiosurgery or whole brain radiotherapy can be performed. The concurrent use of a radiosensitizer further improves intracranial control. Due to its large molecular weight, trastuzumab has a limited ability to cross the blood-brain barrier. However, small tyrosine kinase inhibitors such as lapatinib, has been noted to be a promising agent that can be used as a radiosensitizer to affect HER2-positive breast cancer. This review will outline general management of brain metastases and will focus on preclinical findings regarding the radiosensitizing effect of small molecule HER2 targeting agents.

A Retrospective Analysis for Patients with HER2-Positive Gastric Cancer Who Were Treated with Trastuzumab-Based Chemotherapy: In the Perspectives of Ethnicity and Histology

PURPOSE

While the Trastuzumab for Gastric Cancer (ToGA) trial demonstrated the efficacy and safety of trastuzumab-based chemotherapy in HER2-positive metastatic gastric cancer, the overall survival (OS) benefit was not found in Asian and diffuse-type cancer patients. The aim of the study is to investigate predictive markers for trastuzumab-based chemotherapy.

MATERIALS AND METHODS

Data of patients with HER2-positive gastric cancer treated with trastuzumab-based chemotherapy were analyzed retrospectively.

RESULTS

A total of 168 Asian patients were included. The median age was 60 years (range, 27 to 85 years) and the male:female ratio was 118 (70.2%):50 (29.8%). Fourteen (8.3%), 63 (37.5%), 75 (44.6%), and 11 (6.5%) patients had well, moderately, poorly-differentiated tubular adenocarcinoma and signet ring cell carcinoma, respectively. With 14 complete responses and 73 partial responses, the response rate was 50.6%. The median progression-free survival (PFS) was 10.2 months (95% confidence interval [CI], 8.7 to 11.7), and the median OS was 18.5 months (95% CI, 16.4 to 50.6). Next, we investigated the effect of poorly-differentiated histology (PDH, poorly-differentiated tubular adenocarcinoma+signet ring cell carcinoma) on clinical outcomes. The median PFS (8.9 months vs. 11.5 months, p=0.16) was slightly inferior in PDH patients, and the median OS was significantly shorter in PDH patients (14.6 months vs. 19.0 months, p=0.025).

CONCLUSION

While subset analysis of the ToGA trial demonstrated that trastuzumab-based chemotherapy may not be beneficial for Asians and patients with PDH, our data may suggest that even in Asian patients and patients with PDH, trastuzumab-based chemotherapy could be associated with improved clinical outcomes in patients with HER2-positive gastric cancer.