Adjuvant therapy for breast cancer

Modern Treatment of Skeletal Metastases: Multidisciplinarity and the Concept of Oligometastasis in the Recent Literature

Bone metastases are a major concern in cancer management since they significantly contribute to morbidity and mortality. Metastatic lesions, commonly arising from breast, prostate, lung, and kidney cancers, affect approximately 25% of cancer patients, leading to severe complications such as pain, fractures, and neurological deficits. This narrative review explores contemporary approaches to bone metastases, emphasizing a multidisciplinary strategy and the evolving concept of oligometastatic disease. Oligometastases, defined by limited metastatic spread (1-5 lesions), offer a potential window for curative treatment through aggressive interventions, including stereotactic ablative radiotherapy and resection surgery. Tumor boards, integrating systemic therapies with local interventions, are crucial to optimize treatment. Despite promising results, gaps remain in defining optimal treatment sequences and refining patient selection criteria. Future research should focus on personalized approaches, leveraging biomarkers and advanced imaging to enhance outcomes and the quality of life in patients with bone metastases.

Axillary surgery in breast cancer patients

Surgeons have routinely removed ipsilateral axillary lymph nodes from women with breast cancer for over 100 years. The procedure provides important staging information, enhances regional control of the malignancy and may improve survival. As screening of breast cancer has increased, the mean size of newly diagnosed primary invasive breast cancers has steadily decreased and so has the number of women with lymph node metastases. Recognising that the therapeutic benefit of removing normal nodes may be low, alternatives to the routine level I/II axillary lymph node dissection have been sought. A decade ago sentinel lymph node biopsy (SLNB) was introduced. Because of its high accuracy and relatively low morbidity, this technique is now widely used to identify women with histologically involved nodes prior to the formal axillary node dissection. Specifically, SLNB has allowed surgeons to avoid a formal axillary lymph node biopsy in women with histologically uninvolved sentinel nodes, while identifying women with involved sentinel nodes who derive the most benefit from a completion axillary node dissection. Despite the increasing use of SLNB for initial management of the axilla in women with breast cancer, important questions remain regarding patient selection criteria and optimal surgical methods for performing the biopsy. This article discusses the evolution of axillary node surgery for women with breast cancer.

Adjuvant chemotherapy for early-stage breast cancer

Systemic chemotherapy is an integral component of the adjuvant treatment strategy for women who have early-stage breast cancer and accounts for significant improvements in breast cancer-specific mortality. Decisions regarding adjuvant therapy are increasingly complex with the advent of new therapeutic strategies, a growing body of literature on the molecular biology and natural history of breast cancer, and advances in therapeutic techniques and early detection. Ultimately, the risk-benefit calculus will continue to evolve in response to these advances and one hopes that clinicians will soon be able to tailor treatment recommendations to the biology of an individual cancer and the needs of the affected individual.

Ocular presentations of breast cancer

CONTEXT

Breast cancer is the most common malignancy in women, with increasing incidence in Europe and North America. The frequency of involvement of the eye and visual pathways is reported to be as high as 30% in patients with known metastatic disease. In some cases, ophthalmic involvement can be the first sign of metastatic spread. Metastasis occurs via the haematogenous route and predominantly involves the choroid. Metastases to other ocular structures, the orbit and the visual pathways have also been described. Paraneoplastic effects are rare but significant.

TREATMENTS

Different modalities are employed in the treatment of breast cancer and its metastases. These include chemotherapy and radiotherapy. The ocular adverse effects of these have been well described, but recently developed new treatment modalities, such as monoclonal antibodies, may have different side-effects. With the increasing incidence of breast cancer and the advent of new treatment strategies, the complications of the disease and the sequelae of therapy are highly relevant to both oncologists and ophthalmologists.

Concepts and clinical trials of dose-dense chemotherapy for breast cancer

This article will review the strategy of dose-dense administration of chemotherapy for breast cancer. Increased dose density is achieved by reducing the interval between each dose of chemotherapy. The cumulative drug dose remains constant, but the same amount of drug is administered over a shorter period. Mathematical models of tumor growth have provided the basis for the clinical application of dose-dense chemotherapy. The Norton-Simon model suggests that increasing the dose density of chemotherapy will increase efficacy by minimizing the opportunity for regrowth of tumor cells between cycles of chemotherapy. Intergroup trial 9741, coordinated by the Cancer and Leukemia Group B (CALGB), tested the 2 hypotheses that dose-dense and sequential administration of chemotherapy regimens incorporating doxorubicin, cyclophosphamide, and paclitaxel would improve disease-free survival and overall survival. A statistically significant 4-year disease-free survival advantage was detected for the 2 dose-dense regimens compared with the regimens administered every 3 weeks. The mathematical concepts and previous clinical trials of dose density that contributed to the design of CALGB 9741 will be reviewed. The strengths and limitations of CALGB 9741 will then be discussed before the presentation of future directions of research and recommendations for clinical practice today.

Pharmacodiagnostic testing in breast cancer: focus on HER2 and trastuzumab therapy

Pharmacogenomics is defined as research into inherited genetic variations that determine an individual's response to therapeutic agents. In oncology, pharmacogenomics based on somatic molecular alterations inherited by subsequent cancer cell generations forms the basis of molecular targeting of novel therapeutic agents. What has emerged from clinical experience with such agents is the need for appropriate pharmacodiagnostic approaches to ensure the drugs are correctly targeted. Given the broad range of pharmacogenomic agents currently under evaluation for cancer therapy, it appears that a rapid extension of pharmacodiagnostic profiling will be required in the next 5-10 years, if not sooner. If this is to be successfully achieved, lessons learned in the past, particularly during the development of HER2 (ERBB2) testing for directing trastuzumab therapy in breast cancer, may provide a valuable framework for the development of future pharmacodiagnostic assays system. This article reviews the biological and clinical rationale for targeting breast cancer with trastuzumab and the steps taken to validate and improve pharmacodiagnostic procedures for testing tumor HER2 protein expression and HER2 gene amplification. Attention is given to quality assurance and reproducibility of testing approaches and the optimal selection of patients for response to trastuzumab. This approach serves as a paradigm for the future development of pharmacodiagnostic tests in oncology.

Doxorubicin and paclitaxel enhance the antitumor efficacy of vaccines directed against HER 2/neu in a murine mammary carcinoma model

Introduction

The purpose of the present study was to determine whether cytotoxic chemotherapeutic agents administered prior to immunotherapy with gene vaccines could augment the efficacy of the vaccines.

Methods

Mice were injected in the mammary fat pad with an aggressive breast tumor cell line that expresses HER2/neu. The mice were treated 3 days later with a noncurative dose of either doxorubicin or paclitaxel, and the following day with a gene vaccine to HER2/neu. Two more doses of vaccine were given 14 days apart. Two types of gene vaccines were tested: a plasmid vaccine encoding a self-replicating RNA (replicon) of Sindbis virus (SINCP), in which the viral structural proteins were replaced by the gene for neu; and a viral replicon particle derived from an attenuated strain of Venezuelan equine encephalitis virus, containing a replicon RNA in which the Venezuelan equine encephalitis virus structural proteins were replaced by the gene for neu.

Results

Neither vaccination alone nor chemotherapy alone significantly reduced the growth of the mammary carcinoma. In contrast, chemotherapy followed by vaccination reduced tumor growth by a small, but significant amount. Antigen-specific CD8⁺ T lymphocytes were induced by the combined treatment, indicating that the control of tumor growth was most probably due to an immunological mechanism. The results demonstrated that doxorubicin and paclitaxel, commonly used chemotherapeutic agents for the treatment of breast cancer, when used at immunomodulating doses augmented the antitumor efficacy of gene vaccines directed against HER2/neu.

Conclusions

The combination of chemotherapeutic agents plus vaccine immunotherapy may induce a tumor-specific immune response that could be beneficial for the adjuvant treatment of patients with minimal residual disease. The regimen warrants further evaluation in a clinical setting.

Monitoring neoadjuvant chemotherapy in breast cancer using quantitative diffuse optical spectroscopy: a case study

Presurgical chemotherapy is widely used in the treatment of locally advanced breast cancer. Monitoring the response to therapy can improve survival and reduce morbidity. We employ a noninvasive, near-infrared method based on diffuse optical spectroscopy (DOS) to quantitatively monitor tumor response to neoadjuvant chemotherapy. DOS was used to monitor tumor response in one patient with locally advanced breast cancer throughout the course of her therapy. Measurements were performed prior to doxorubicin-cyclophosphamide therapy and at several time points over the course of three treatment cycles (68 days). Our results show strong tumor to normal (T/N) tissue contrast in total hemoglobin concentration (T/N=2.4), water fraction (T/N=6.9), tissue hemoglobin oxygen saturation, S(t)O(2) (T/N=0.9), and lipid fraction (T/N=0.7) prior to treatment. Over a 10-week period, the peak total hemoglobin and water dropped 56 and 67%, respectively. Lipid content nearly returned to baseline (T/N =0.9) while S(t)O(2) exceeded pretreatment levels (T/N =1.5). Approximately half of the hemoglobin and water changes occurred within 5 days of treatment (26 and 37%, respectively). These data suggest that noninvasive, quantitative optical methods that characterize tumor physiology may be useful in assessing and optimizing individual response to neoadjuvant chemotherapy.

Cellular uptake and concentrations of tamoxifen upon administration in poly(epsilon-caprolactone) nanoparticles

PURPOSE

In an attempt to increase the local concentration of tamoxifen in estrogen receptor positive breast cancer cells, we have prepared and characterized poly(epsilon-caprolactone) (PCL) nanoparticle formulation.

METHODS

PCL (mol wt 14,800 daltons) nanoparticles were prepared by the solvent displacement method in acetone-water system in the presence of Pluronic F- 68. PCL nanoparticles, labeled with rhodamine123, were incubated with MCF-7 estrogen receptor positive breast cancer cells to determine uptake, intracellular distribution, and localization as a function of time. Intracellular drug concentrations over a specified period of time using different initial doses were examined using tritiated [3H]-tamoxifen.

RESULTS

A significant fraction of the administered rhodamine123-loaded PCL nanoparticles was found in the perinuclear region of the MCF-7 cells, where estrogen receptors are also localized, after 1 hour of incubation. Measurements of the intracellular concentrations revealed that most of the administered nanoparticle dose was internalized within the first 30 minutes of incubation, and the uptake followed saturable transport kinetics.

CONCLUSION

Results of this study show that PCL nanoparticles were rapidly internalized in MCF-7 cells and intracellular tamoxifen concentrations followed a saturable process. This approach may provide better therapeutic benefit by delivering the drug locally, near the tumor cells, for a longer period of time.

Cellular uptake and concentrations of tamoxifen upon administration in poly(epsilon-caprolactone) nanoparticles

PURPOSE

In an attempt to increase the local concentration of tamoxifen in estrogen receptor positive breast cancer cells, we have prepared and characterized poly(epsilon-caprolactone) (PCL) nanoparticle formulation.

METHODS

PCL (mol wt 14,800 daltons) nanoparticles were prepared by the solvent displacement method in acetone-water system in the presence of Pluronic F- 68. PCL nanoparticles, labeled with rhodamine123, were incubated with MCF-7 estrogen receptor positive breast cancer cells to determine uptake, intracellular distribution, and localization as a function of time. Intracellular drug concentrations over a specified period of time using different initial doses were examined using tritiated [3H]-tamoxifen.

RESULTS

A significant fraction of the administered rhodamine123-loaded PCL nanoparticles was found in the perinuclear region of the MCF-7 cells, where estrogen receptors are also localized, after 1 hour of incubation. Measurements of the intracellular concentrations revealed that most of the administered nanoparticle dose was internalized within the first 30 minutes of incubation, and the uptake followed saturable transport kinetics.

CONCLUSION

Results of this study show that PCL nanoparticles were rapidly internalized in MCF-7 cells and intracellular tamoxifen concentrations followed a saturable process. This approach may provide better therapeutic benefit by delivering the drug locally, near the tumor cells, for a longer period of time.

Antiangiogenic and antitumor effects of a protein kinase Cbeta inhibitor in human breast cancer and ovarian cancer xenografts

In cell culture, the compound 317615 2HCl, a potent inhibitor of VEGF-stimulated HUVEC proliferation, was not very effective against MX-1 breast cancer cells (IC50= 8.1 microM) or SKOV-3 ovarian carcinoma cells (IC50 = 9.5 microM). Exposure to combinations of paclitaxel or carboplatin and 317615 x 2HCl with MX-1 cells in culture resulted in cell survival that reflected primarily additivity of the two agents. Exposure of SKOV-3 cells to paclitaxel or carboplatin along with 317615 2HCl resulted in cell survivals that reflected additivity of 317615 x 2HCl with paclitaxel and greater-than-additive cytotoxicity with carboplatin. Administration of 317615 x 2HCI orally twice daily to nude mice bearing subcutaneous MX-1 tumors or SKOV-3 tumors resulted in a decreased number of intratumoral vessels as determined by CD31 and CD105 staining with decreases of 35% and 43% in MX-1 tumors and 60% and 75% in SKOV-3 tumors, respectively. 317615 x 2HCl was an active antitumor agent against the MX-1 xenograft and increased the tumor growth delay produced by paclitaxel by 1.7-fold and the tumor growth delay produced by carboplatin by 3.8-fold. Administration of 317615 x 2HCl also increased the tumor growth delay produced by fractionated radiation therapy in the MX-1 tumor. Treatment with 317615 x 2HCl alone increased the lifespan of animals bearing intraperitoneal SKOV-3 xenografts by 1.9 fold compared with untreated control animals. The combination of paclitaxel and 317615 x 2HCl resulted in 100% 120-day survival of SKOV-3 bearing animals. Administration of 317615 x 2HCl along with carboplatin to animals bearing the SKOV-3 tumor produced a 1.8-fold increase in lifespan compared with carboplatin alone. 317615 x 2HCl is a promising new antiangiogenic agent that is in early phase clinical testing.

Sentinel lymph node biopsy for breast cancer

Sentinel lymph node biopsy (SLNB) is an emerging surgical technique to improve lymph node staging for breast cancer. Despite the rapid development of this technique, there remain aspects of SLNB that need to be further defined to provide a standardized approach. Variables, including patient selection, technical details for the performance of SLNB, extent of pathologic evaluation of the sentinel lymph node, and the impact of micrometastases, are areas of controversy. This paper reviews the controversies and discusses available data as well as personal experience and opinion.

Molecular targets for breast cancer therapy and prevention

The recent completion of the human genome sequence has raised great hopes for the discovery of new breast cancer therapies based on newly-discovered genes linked to breast cancer development and progression. Here we describe breast cancer therapies that have emerged from gene-based scientific efforts over the past 20 years and that are now approved for clinical testing or treatment.

Change in women's diet and body mass following intensive intervention for early-stage breast cancer

OBJECTIVE

To determine the effectiveness of an intensive dietary intervention on diet and body mass in women with breast cancer.

DESIGN

Randomized clinical trial.

SUBJECTS

172 women aged 20 to 65 years with stage I or II breast cancer.

INTERVENTION

A 15-session, mainly group-based and dietitian-led nutrition education program (NEP) was compared to a mindfulness-based stress reduction clinic program (SRC); or usual supportive care (UC).

MAIN OUTCOME MEASURES

Dietary fat, complex carbohydrates, fiber, and body mass were measured.

STATISTICAL ANALYSIS

In addition to descriptive statistics, analysis of variance was conducted to test for differences according to intervention group.

RESULTS

Of the 157 women with complete dietary data at baseline, 149 had complete data immediately postintervention (at 4 months) and 146 had complete data at 1 year. Women randomized to NEP (n = 50) experienced a large reduction in fat consumption (5.8% of energy as fat) at 4 months and much of this reduction was preserved at 1 year (4.1% of energy) (both P < .0002) vs no change in either SRC (n = 51) or UC (n = 56). A 1.3-kg reduction in body mass was evident at 4 months in the NEP group (P = .003) vs no change in the SRC and UC groups. Women who had higher-than-average expectations of a beneficial effect of the intervention experienced larger changes.

APPLICATIONS

Dietitians' use of group nutrition interventions appear to be warranted. Increasing their effectiveness and maintaining high levels of adherence may require additional support, including the involvement of significant others, periodic individual meetings, or group booster sessions.