Histological assessment of therapeutic response in breast cancer

Accumulation of CD56+ CD16- Natural Killer Cells in Response to Preoperative Chemotherapy for Breast Cancer

Background

The activation of the antitumor immune responses of T cells and natural killer (NK) cells is important to induce breast tumor shrinkage via preoperative chemotherapy. We evaluated how antitumor immune responses contribute to the effects of such therapy.

Methods

Forty-three patients with stages I - IV breast cancer who underwent surgery between August 2018 and Jun 2023 after preoperative chemotherapy were enrolled. Peripheral natural killer (pNK) cell activity was assessed by 51Cr-release assay, and the counts and percentages of CD4+, CD8+, and NK cells and their subsets in peripheral blood were measured before and after chemotherapy by two-color flow cytometry. Associations of cell population changes with chemotherapy responses were analyzed.

Results

On univariate analysis, relative to grade (G) ≤ 1 effects, G ≥ 2 therapeutic effects were associated significantly with human epidermal growth factor receptor 2 (HER-2)+ breast cancer (P = 0.024) and post-chemotherapy CD56+ CD16- NK cell accumulation (8.4% vs. 5.5%, P = 0.042), and tended to be associated with increased pre-chemotherapy CD56+ CD16- NK cell percentages (5.4% vs. 3.3%, P = 0.054) and pNK cell activity (42.0% vs. 34.5%, P = 0.057). The accumulation and increased percentage of CD56+ CD16- NK cells in patients with G ≥ 2 effects were not associated with changes in pNK cell activity or the disappearance of axillary lymph-node metastases. On multivariate analysis, G ≥ 2 therapeutic effects tended to be associated with higher pre-chemotherapy pNK levels (odds ratio = 0.96; 95% confidence interval: 0.921 - 1.002; P = 0.067).

Conclusions

The accumulation of the immunoregulatory CD56+ CD16- NK cell subset in the peripheral blood before and after chemotherapy may lead to the production of cytokines that induce an antitumor immune response. Activation of the immune response mediated by CD56+ CD16- pNK cells after chemotherapy and their high counts before chemotherapy may contribute to the improvement of therapeutic effects against breast cancer.

Cytomorphological Disparities in Invasive Breast Cancer Cells following Neoadjuvant Endocrine Therapy and Chemotherapy

INTRODUCTION

Neoadjuvant endocrine therapy (NAE) offers a breast-conserving surgery rate and clinical response rate similar to those of neoadjuvant chemotherapy (NAC), while presenting fewer adverse events and lower pathological complete response rates. The assessment of pathological response determines degenerative changes and predicts the prognosis of breast cancer treated with NAC. This study clarified the degenerative changes occurring in breast cancer following NAE.

METHODS

Our study encompassed two groups: NAE, consisting of 15 patients, and NAC, comprising 18 patients. Tissue samples were obtained from core needle biopsies and surgeries. Nuclear and cell areas were calculated using Autocell analysis. Furthermore, we assessed markers associated with microtubule depolymerization (KIF2A) and initiators of apoptosis (caspase-9).

RESULTS

In the NAC group, we observed significant increases in both cytoplasmic and cell areas. These changes in cytoplasm and cells were notably more pronounced in the NAC group compared to the NAE group. After treatment, KIF2A exhibited a decrease, with the magnitude of change being greater in the NET group than in the NAC group. However, no discernible differences were found in caspase-9 expression between the two groups.

CONCLUSION

Our findings indicate that NAE induces condensation in cancer cells via cell cycle arrest or apoptosis. Conversely, NAC leads to cell enlargement due to the absence of microtubule depolymerization. These discrepancies underscore the importance of accounting for these distinctions when establishing criteria for evaluating pathological responses.

Breast cancer recurrence and survival rates in patients who underwent breast-conserving surgery under non-mechanically ventilated anesthesia

BACKGROUND

Recurrence after primary treatment is an important obstacle to the curing of primary breast cancer. Less-immunosuppressive anesthetic techniques, such as local anesthesia with lidocaine, intravenous anesthesia (IVA) with propofol, and/or sedation with midazolam under spontaneous breathing may reduce breast cancer recurrence compared with standard general anesthesia techniques such as IVA and inhalation anesthesia with opioids under mechanical ventilation.

AIM

The aim of this study was to analyze the factors involved in breast cancer recurrence in patients who underwent breast-conserving surgery (BCS) under non-mechanically ventilated anesthesia.

METHODS

The study included 491 consecutive patients with stages 0-III breast cancer who underwent BCS/axillary lymph-node management with local anesthesia and IVA and/or sedation under non-mechanical ventilation between May 2008 and September 2021. Survival and recurrence were assessed by retrospective cohort analysis.

RESULTS

The median follow-up period was 2565 days (range, 28-4834 days). The overall and breast cancer-specific survival rates were 92.9% and 95.6%, respectively. Twenty-one deaths, of which 11 were breast cancer-related, occurred. Disease recurred in 29 (5.9%) patients, of whom 15 patients received neoadjuvant chemotherapy (NAC) and 14 patients received adjuvant therapy (chemotherapy in 12 cases). The surgical procedure performed, but not other clinicopathological factors [recurrence site, P stage, tumor subtype, and disease-free interval (DFI)], differed between the NAC and adjuvant therapy groups. The DFI tended to be shorter in the NAC group than in the adjuvant therapy group. The pathological therapeutic effect grade after NAC was 1 in 12 patients and ≥2 in 3 patients.

CONCLUSION

More than 50% (15/29) of patients with recurrence who underwent BCS were given NAC, but most patients did not respond to it. Similarly, adjuvant chemotherapy may not have contributed to the eradication of residual tumor cells after BCS. To reduce breast cancer recurrence in patients undergoing BCS, treatment strategies, especially for patients who do not respond to NAC or adjuvant chemotherapy, need to be developed. Non-mechanical ventilation anesthesia may also affect the incidence of breast cancer recurrence.

Targeting Amino Acid Metabolic Reprogramming via L-Type Amino Acid Transporter 1 (LAT1) for Endocrine-Resistant Breast Cancer

The PI3K/Akt/mTOR pathway has been well known to interact with the estrogen receptor (ER)-pathway and to be also frequently upregulated in aromatase inhibitor (AI)-resistant breast cancer patients. Intracellular levels of free amino acids, especially leucine, regulate the mammalian target of rapamycin complex 1 (mTORC1) activation. L-type amino acid transporters such as LAT1 and LAT3 are associated with the uptake of essential amino acids. LAT1 expression could mediate leucine uptake, mTORC1 signaling, and cell proliferation. Therefore, in this study, we explored amino acid metabolism, including LAT1, in breast cancer and clarified the potential roles of LAT1 in the development of therapeutic resistance and the eventual clinical outcome of the patients. We evaluated LAT1 and LAT3 expression before and after neoadjuvant hormone therapy (NAH) and examined LAT1 function and expression in estrogen deprivation-resistant (EDR) breast carcinoma cell lines. Tumors tended to be in advanced stages in the cases whose LAT1 expression was high. LAT1 expression in the EDR cell lines was upregulated. JPH203, a selective LAT1 inhibitor, demonstrated inhibitory effects on cell proliferation in EDR cells. Hormone therapy changed the tumor microenvironment and resulted in metabolic reprogramming through inducing LAT1 expression. LAT1 expression then mediated leucine uptake, enhanced mTORC1 signaling, and eventually resulted in AI resistance. Therefore, LAT1 could be the potential therapeutic target in AI-resistant breast cancer patients.

Hysterectomy for Recurrent/Residual Cervical Cancer Following Definitive Radiotherapy

BACKGROUND/AIM

Radical hysterectomy has been used for local recurrent or persistent (LR) cervical cancer after radiotherapy (RT), but the rate of serious complications is high and tolerance is low. This study determined the efficacy, safety, and prognostic factors of adjuvant simple hysterectomy in LR cervical cancer post-RT.

PATIENTS AND METHODS

A total of 21 patients who underwent hysterectomy for LR cervical cancer post-RT in our Department between May 2007 and September 2018 were included in the study. Primary, definitive RT was performed. Histological response by definitive RT in the extirpated uterus was classified on the basis of histological response criteria: effect (Ef) 0-3.

RESULTS

The 5-year overall survival (OS) and disease-free survival (DFS) rates were 51.9% and 50.1%, respectively. Ef 1 was significantly associated with poorer prognosis compared to Ef 2 or Ef 3.

CONCLUSION

Adjuvant hysterectomy could be a treatment of choice for LR cervical cancer post-RT.

L-type amino acid transporter 1 is associated with chemoresistance in breast cancer via the promotion of amino acid metabolism

¹⁸F-FDG PET/CT has been used as an indicator of chemotherapy effects, but cancer cells can remain even when no FDG uptake is detected, indicating the importance of exploring other metabolomic pathways. Therefore, we explored the amino acid metabolism, including L-type amino acid transporter-1 (LAT1), in breast cancer tissues and clarified the role of LAT1 in therapeutic resistance and clinical outcomes of patients. We evaluated LAT1 expression before and after neoadjuvant chemotherapy and examined the correlation of glucose uptake using FDG-PET with the pathological response of patients. It revealed that LAT1 levels correlated with proliferation after chemotherapy, and amino acid and glucose metabolism were closely correlated. In addition, LAT1 was considered to be involved in treatment resistance and sensitivity only in luminal type breast cancer. Results of in vitro analyses revealed that LAT1 promoted amino acid uptake, which contributed to energy production by supplying amino acids to the TCA cycle. However, in MCF-7 cells treated with chemotherapeutic agents, oncometabolites and branched-chain amino acids also played a pivotal role in energy production and drug resistance, despite decreased glucose metabolism. In conclusion, LAT1 was involved in drug resistance and could be a novel therapeutic target against chemotherapy resistance in luminal type breast cancer.

Immune factors associated with the pathological and therapeutic effects of preoperative chemotherapy in patients with breast cancer

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The immune factors that determine the pathological and therapeutic effects of preoperative chemotherapy in patients with breast cancer are associated with local and systemic immune responses in the presence of tumor-infiltrating lymphocytes, in collaboration with downregulation of immunosuppressive factors mediated by vascular endothelial growth factor (VEGF) and cytotoxic T lymphocyte antigen 4 (CTLA-4) in regulatory T cells (Tregs) in the tumor microenvironment.

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Multivariate analysis showed that grade 2 and better therapeutic effects tended to be associated with higher natural killer cell levels after preoperative chemotherapy (odds ratio = 1.02; 95% confidence interval, 0.99–1.05; p = 0.07).

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Therapy targeting VEGF and CTLA-4 in Tregs to overcome tumor-derived immunosuppression may enhance the pathological and therapeutic responses to preoperative chemotherapy in patients with breast cancer.

Immune activation plays an important role in achieving the pathological and therapeutic effects of preoperative chemotherapy in patients with breast cancer. We evaluated how the immune response contributes to various therapeutic effects. This study was conducted on 43 patients with stages II–IV breast cancer who received preoperative chemotherapy followed by surgery. Peripheral natural killer (pNK) cell activity and the neutrophil-lymphocyte ratio, lymphocyte-monocyte ratio, and platelet-lymphocyte ratio (PLR) were assessed before and after chemotherapy. Tumor-infiltrating lymphocytes (TILs) and levels of 14 tumor microenvironmental factors, analyzed by next-generation sequencing, were assessed in formalin-fixed, paraffin-embedded sections of preoperative biopsy samples and surgical specimens. Univariate analysis showed that grade 2 (G2) and better therapeutic effects were significantly associated with human epidermal growth factor receptor 2 (HER-2)-positive cancer, lower PLRs, and higher NK cell and interleukin-6 levels after chemotherapy. The disappearance of axillary lymph-node metastasis was significantly associated with HER-2-positive cancer; increased pNK cell activity and lower PLRs and vascular endothelial growth factor (VEGF) levels after chemotherapy; and increased cytotoxic T lymphocyte antigen 4 (CTLA-4) levels in regulatory T cells (Tregs) and ≥5% TILs before chemotherapy. Multivariate analysis showed that G2 and better therapeutic effects tended to be associated with higher NK cell levels after chemotherapy (odds ratio = 1.02; 95% confidence interval, 0.99–1.05; P = 0.07). The activation of local and systemic immune responses by downregulation of immunosuppressive factors, such as VEGF and CTLA-4 in Tregs, had variable pathological and therapeutic effects after preoperative chemotherapy in patients with breast cancer.

Evaluation of the Efficacy of Neoadjuvant Chemotherapy for Breast Cancer

Neoadjuvant chemotherapy is increasingly used in breast cancer, especially for downstaging the primary tumor in the breast and the metastatic axillary lymph node. Accurate evaluations of the response to neoadjuvant chemotherapy provide important information on the impact of systemic therapies on breast cancer biology, prognosis, and guidance for further therapy. Moreover, pathologic complete response is a validated and valuable surrogate prognostic factor of survival after therapy. Evaluations of neoadjuvant chemotherapy response are very important in clinical work and basic research. In this review, we will elaborate on evaluations of the efficacy of neoadjuvant chemotherapy in breast cancer and provide a clinical evaluation procedure for neoadjuvant chemotherapy.

Immune correlates of the differing pathological and therapeutic effects of neoadjuvant chemotherapy in breast cancer

PURPOSE

To evaluate immune responses paralleling the pathological and therapeutic effects of neoadjuvant chemotherapy (NAC) in the tumor microenvironment of breast cancer.

PATIENTS AND METHODS

38 patients with stages II and III breast cancer received NAC followed by surgery in 2012-2018. Peripheral natural killer (pNK) cell activity, tumor-infiltrating lymphocytes (TILs), and levels of tumor microenvironmental factors were assessed before and after NAC.

RESULTS

In univariate analysis, grade 2 (G2) and better therapeutic effects were significantly associated with high post-NAC levels of NK cells and interleukin-6, and tended to be associated with higher CD4, CD8 and CTLA-4 transcripts. Disappearance of axillary lymph node metastasis (Ax+) was significantly associated with 1) increased NK and pNK levels, 2) decreased vascular endothelial growth factor (VEGF) transcripts after NAC, 3) the presence of ≥5% TILs, and tended to be associated with higher CTLA-4 levels before NAC. Multivariate analysis showed that G2 and better therapeutic effects were significantly associated with higher NK levels after NAC (OR = 1.07, 95% CI 1.00-1.14; p = 0.0255), and that disappearance of Ax+ was significantly associated with the presence of ≥5% pre-NAC TILs (OR = 19.87, 95% CI 2.24-175.80; p = 0.0072).

CONCLUSIONS

Increased NK cells after NAC, together with increased CD4⁺ and CD8⁺ T-cells, and decreased CTLA-4+ T cells and VEGF correlate with beneficial therapeutic effects. Systemic activation of pNK cell activity and the presence of pre-NAC TILs may improve the elimination of Ax + together with decreased immunosuppression by VEGF in tumors.

PROBING BREAST CANCER THERAPEUTIC RESPONSES BY DNA CONTENT PROFILING

Background. Discrepancies in the interpretation of breast cancer therapeutic responses still exist mainly because of lack of standardized assessment criteria and methods. Objective. DNA content profiling of cells in the affected (cancerous) tissue before and after neoadjuvant chemotherapy (NAC) was applied to facilitate interpretation of therapeutic responses. Methods. Both diagnostic biopsy and operation materials representing the tissue of primary tumors surgically removed after NAC were subjected to DNA image cytometry. Polyploidy and aneuploidy in DNA histograms were evaluated with a prognostic Auer typing. Stemline DNA index (DI) values and percentages of cells that polyploidize (>4.5C) were also determined. Immunofluorescence staining was applied to evaluate proliferation (Ki-67), invasiveness (CD44), and self-renewal factors characteristic for stem cells (SOX2 and NANOG). Results. DNA content profiles of 12 breast cancer cases, of which 7 were triple-negative, revealed the features of tumor non-responsiveness to NAC in 7 cases, of which 5 were triple-negative. Among non-responsive cases there were 3 cases that showed enhanced polyploidization, suggesting the negative NAC effect. Near-triploid (DI=1.26-1.74) triple-negative cases were determined as most resistant to NAC. Cycling near-triploid cells may contribute to the excessive numbers of >4.5C cells. Polyploid cells were positive for Ki-67, CD44, SOX2, and NANOG. Conclusions. DNA content profiling data provide additional helpful information for interpreting therapeutic responses in NAC-treated breast cancers. Polyploid tumor cells possessing stem cell features can be induced by NAC. Because NAC effects in some cases may be unfavorable, the use of the further treatment strategy should be carefully considered.

Differences in Ki67 expressions between pre- and post-neoadjuvant chemotherapy specimens might predict early recurrence of breast cancer

The prognosis of breast cancer patients not obtaining a pathological complete response (pCR) with neoadjuvant chemotherapy (NAC) is poorer than that of pCR patients. Identifying new prognostic factors for non-pCR patients is important because fractions of this population might benefit from novel adjuvant treatments currently under development. High Ki67 expression in remnant disease after NAC has been described as a poor prognostic factor. Studies have shown that a reduction in Ki67 expression is more often observed in good responders to chemotherapy. We hypothesized that the change in Ki67 expression might be useful for predicting patient outcomes and thus retrospectively examined pairs of biopsy and surgical specimens of breast tissue from individual patients. One hundred sixteen patients with remnant invasive disease in the breast, who received NAC and underwent surgery at our institution, were retrospectively examined. Differences in Ki67 expression between pre- and post-NAC specimens were analyzed in relation to patient outcomes. The mean Ki67 expression value after NAC was higher in patients who developed metastasis than in those without metastasis (P<.01). Tumors showing higher Ki67 expression in the surgical than in the biopsy specimen were more frequent in patients with metastasis (P<.01). This trend was more obvious in patients who developed metastasis within 1 year after surgery. Our results indicate that a difference in Ki67 expressions after versus before NAC might be an important predictor of early metastasis. Evaluating not only absolute Ki67 values, but also any changes in response to NAC, may improve the prediction of patient outcomes.

Preoperative neoadjuvant chemotherapy using nanoparticle albumin-bound paclitaxel followed by epirubicin and cyclophosphamide for operable breast cancer: a multicenter phase II trial

Background

Recently, the use of taxane-based regimens before anthracycline-based regimens has been shown to achieve high pathological complete response (pCR) rates in patients with breast cancer. Nanoparticle albumin-bound paclitaxel (nab-PTX) has been reported as highly effective and less toxic compared with Cremophor-based Taxol. This phase II clinical trial evaluated the safety and efficacy of preoperative neoadjuvant chemotherapy (NAC) with nab-PTX followed by an epirubicin plus cyclophosphamide (EC)-based regimen for operable breast cancer.

Patients and methods

From June 2012 to January 2014, four cycles of every-3-week (q3w) nab-PTX [plus q3w trastuzumab in cases of human epidermal growth factor 2 (HER2) positivity] followed by four cycles of q3w EC were administered to patients with operable breast cancer (stage IC–IIIA). The primary endpoint was the pCR rate (ypT0/TisypN0).

Results

A total of 55 patients were enrolled, 54 of whom received at least one nab-PTX dose. All patients underwent radical surgery after chemotherapy. The overall pCR rate was 22.2% (p = 0.006). The pCR rates for patients with the luminal B, luminal/HER2, HER2-rich, and triple-negative breast cancer subtypes were 10.5, 29.4, 60, and 15.4%, respectively. Stepwise logistic regression analysis revealed only HER2 as a significant factor for pCR (odds ratio 5.603; p = 0.024). The expression of secreted protein acidic and rich in cysteine showed no association with pCR. The clinical response rate was 70.4% (38/54), and the safety profile was tolerable.

Conclusion

Preoperative NAC with nab-PTX followed by EC is effective and safe for operable breast cancer.

Prognostic significance of histological therapeutic effect in preoperative chemotherapy for breast cancer

To establish a prognostic prediction system, we examined the relationships between prognosis and histological therapeutic effect or ypTNM classification in 258 breast cancer patients who received neoadjuvant chemotherapy. The case distribution according to therapeutic effect was nine patients (3.5%) with Grade 0, 169 (65.5%) with Grade 1, 58 (22.5%) with Grade 2, and 22 (8.5%) with Grade 3. The 5-year overall survival (OS) rate by therapeutic effect was 56% in Grade 0, 81% in Grade 1, 87% in Grade 2, and 96% in Grade 3. The higher the therapeutic effect the better the prognosis, with a significant difference among the groups (P = 0.008). The case distribution according to ypTNM classification was 20 patients (7.8%) with Stage 0, 83 (32.2%) with Stage I, 77 (29.8%) with Stage II, and 78 (30.2%) with Stage III. The 5-year OS rate by ypTNM classification was 95% in Stage 0, 94% in Stage I, 89% in Stage II, and 59% in Stage III. While prognosis was mostly comparable in Stages 0 and I, in the other stages it became significantly worse as residual cancer increased (P < 0.001). The prognosis of breast cancer patients with neoadjuvant chemotherapy can be predicted by histological therapeutic effect and staging classification of residual cancer.