Real World and Public Health Perspectives of Intraoperative Radiotherapy in Early-Stage Breast Cancer: A Multidisciplinary Analysis Beyond the Statistical Facts.

Breast conservation therapy (BCT) (usually a lumpectomy plus radiotherapy (RT)) has become a standard alternative to radical mastectomy in early-stage breast cancers with equal, if not higher, survival rates. The established standard of the RT component of the BCT had been about six weeks of Monday through Friday external beam RT to the whole breast (WBRT). Recent clinical trials have shown that partial breast radiation therapy (PBRT) to the region surrounding the lumpectomy cavity with shorter courses can result in equal local control, survival, and slightly improved cosmetic outcomes. Intraoperative RT (IORT) wherein RT is administered at the time of operation for BCT to the lumpectomy cavity as a single-fraction RT is also considered PBRT. The advantage of IORT is that weeks of RT are avoided. However, the role of IORT as part of BCT has been controversial. The extreme views go from "I will not recommend to anyone" to "I can recommend to all early-stage favorable patients." These divergent views are due to difficulty in interpreting the clinical trial results. There are two modalities of delivering IORT, namely, the use of low-energy 50 kV beams or electron beams. There are several retrospective, prospective, and two randomized clinical trials comparing IORT versus WBRT. Yet, the opinions are divided. In this paper, we try to bring clarity and consensus from a highly broad-based multidisciplinary team approach. The multidisciplinary team included breast surgeons, radiation oncologists, medical physicists, biostatisticians, public health experts, nurse practitioners, and medical oncologists. We show that there is a need to more carefully interpret and differentiate the data based on electron versus low-dose X-ray modalities; the randomized study results have to be extremely carefully dissected from biostatistical points of view; the importance of the involvement of patients and families in the decision making in a very transparent and informed manner needs to be emphasized; and the compromise some women may be willing to accept between 2-4% potential increase in local recurrence (as interpreted by some of the investigators in IORT randomized studies) versus mastectomy. We conclude that, ultimately, the choice should be that of women with detailed facts of the pros and cons of all options being presented to them from the angle of patient/family-focused care. Although the guidelines of various professional societies can be helpful, they are only guidelines. The participation of women in IORT clinical trials is still needed, and as genome-based and omics-based fine-tuning of prognostic fingerprints evolve, the current guidelines need to be revisited. Finally, the use of IORT can help rural, socioeconomically, and infrastructure-deprived populations and geographic regions as the convenience of single-fraction RT and the possibility of breast preservation are likely to encourage more women to choose BCT than mastectomy. This option can also likely lead to more women choosing to get screened for breast cancer, thus enabling the diagnosis of breast cancer at an earlier stage and improving the survival outcomes.

The Will Rogers phenomenon, breast cancer and race.

BACKGROUND: The Will Rogers phenomenon [WRP] describes an apparent improvement in outcome for patients' group due to tumor grade reclassification. Staging of cancers is important to select appropriate treatment and to estimate prognosis. The WRP has been described as one of the most important biases limiting the use of historical cohorts when comparing survival or treatment. The main purpose of this study is to assess whether the WRP exists with the move from the AJCC 7th to AJCC 8th edition in breast cancer [BC] staging, and if racial differences are manifested in the expression of the WRP. METHODS: This is a retrospective analysis of 300 BC women (2007-2017) at an academic medical center. Overall survival [OS] and disease-free survival [DFS] was estimated by Kaplan-Meier analysis. Bi and multi-variate Cox regression analyses was used to identify racial factors associated with outcomes. RESULTS: Our patient cohort included 30.3% Caucasians [Whites] and 69.7% African-Americans [Blacks]. Stages I, II, III, and IV were 46.2, 26.3, 23.1, and 4.4% of Whites; 28.7, 43.1, 24.4, and 3.8% of Blacks respectively, in anatomic staging (p = 0.043). In prognostic staging, 52.8, 18.7, 23, and 5.5% were Whites while 35, 17.2, 43.5, and 4.3% were Blacks, respectively (p = 0.011). A total of Whites (45.05% vs. 47.85%) Blacks, upstaged. Whites (16.49% vs. 14.35%) Blacks, downstaged. The remaining, 38.46 and 37.79% patients had their stages unchanged. With a median follow-up of 54 months, the Black patients showed better stage-by-stage 5-year OS rates using 8th edition compared to the 7th edition (p = 0.000). Among the Whites, those who were stage IIIA in the 7th but became stage IB in the 8th had a better prognosis than stages IIA and IIB in the 8th (p = 0.000). The 8th showed complex results (p = 0.176) compared to DFS estimated using the 7th edition (p = 0.004). CONCLUSION: The WRP exists with significant variability in the move from the AJCC 7th to the 8th edition in BC staging (both White and Black patients). We suggest that caution needs to be exercised when results are compared across staging systems to account for the WRP in the interpretation of the data.

Systemic toxicities of trastuzumab-emtansine predict tumor response in HER2+ metastatic breast cancer.

The mechanism by which trastuzumab-emtansine (T-DM1) causes systemic toxicities apart from trastuzumab alone is currently unknown. We hypothesized that the systemic toxicities from T-DM1 may have been caused by the free and active maytansine released from the lysed HER2+ tumor cells, and if so, they may correlate with the response to treatment and eventually disease-free survival or patient outcome. In a retrospective, observational study, we evaluated 73 patients from three centers in the United States and Canada with advanced HER2+ breast cancer that received at least one dose of T-DM1. Toxicity grades were summed to create a corresponding toxicity sum score (TSS), and its association with clinical outcomes was analyzed. A higher TSS was significantly associated with longer progression-free survival with an HR = 0.66 [95% confidence interval [CI]: 0.47-0.92], P = .014, for each 1-point increase in the TSS score. Adjusted for baseline platelet count, aspartate transaminase and alanine transaminase, higher TSS remains significantly associated with longer progression-free survival with adjusted HR = 0.67 [95% CI: 0.47-0.93], P = .020. The analysis suggests that the systemic toxicities of T-DM1 were significantly correlated with its clinical efficacy. This is the first report to correlate the systemic toxicities of T-DM1 with clinical outcome. Further, this suggests that systemic toxicities of antibody-drug conjugates (ADCs) may serve as a predictive biomarker, particularly if noncleavable linkers are used. If confirmed in larger prospective studies, the present finding is significant because most ADCs do not have a biomarker predictive of clinical outcome other than the presence or absence of the antibody target.

Hormone receptor-independent CXCL10 production is associated with the regulation of cellular factors linked to breast cancer progression and metastasis.

Breast cancer (BC) is a major health problem for women around the world. Although advances in the field of molecular therapy have been achieved, the successful therapeutic management of BC, particularly metastatic disease, remains a challenge for patients and clinicians. One of the areas of current investigation is the circulating tumor cells (CTCs), which have a determinant role in the development of distant metastasis. At the present, many of the available treatment strategies for metastatic disease are of limited benefit. However, the elucidation of the mechanisms of tumor progression and metastasis may help to identify key molecules/components that may function as therapeutic targets in the future. In the present study, the functional analysis of CTCs revealed their ability to grow and proliferate to form colonies. Immunofluorescence staining of the CTCs' colonies exhibits elevated expression of cell growth and survival associated proteins such as, survivin, ERK and Akt1. More importantly, the functional screening of the chemokine profile in BC patients' sera revealed an HR-independent elevation of the chemokine CXCL10 when compared to healthy controls. The analysis of chemokines CXCL9 and CXCL11 demonstrated an HR-dependent production pattern. The levels of both CXCL9 and CXCL11 were markedly high in HR+ patients' sera when compared to HR- patients and healthy controls. The functional analysis of HR+ and HR- BC derived cell lines when cultivated in media supplemented with patients' sera demonstrated the alteration of tumor progression and metastasis related proteins. We noted the induction of survivin, ß-catenin, MKP-1, pERK, CXCR4 and MMP-1 both at the protein and mRNA levels. The induction of those proteins was in keeping with patients' sera induced cell proliferation as measured by the MTT assay. In conclusion, our data emphasizes the role of chemokines, especially CXCL10, in BC progression and metastasis via the induction of signaling pathways, which mainly involve survivin, ß-catenin, MKP-1 and MMP-1.

Toll-like receptor (TLR) expression of immune system cells from metastatic breast cancer patients with circulating tumor cells.

The risk posed by breast cancer represents a complex interaction among factors affecting tumor immunity of the host. Toll-like receptors (TLRs) are members of the innate immune system and generally function to attract host immune cells upon activation. However, the good intentions of TLRs are sometimes not transferred to positive long-term effects, due to their involvement in exacerbating inflammatory effects and even contributing to continued inflammation. Chronic inflammatory states are considered to favor an increased predisposition to cancer, with continuous activation of inflammatory cytokines and other hallmarks of inflammation exerting a deleterious effect. Circulating tumor cells (CTCs) are neoplastic cells present in the peripheral blood circulation that have been found to be an indicator of disease progression and long-term survival. In the present study, we examined the expression of TLRs on dendritic cells, which play a major role in eliciting anti-tumor immunity, in metastatic breast cancer patients with CTCs. Flow cytometric data showed significant differences between circulating tumor cell (CTC) positive patients and CTC negative patients in their expression of TLR2 by CD8 positive cytotoxic T cells and TLR2, TLR4, TLR3, and TLR8 by CD11c positive dendritic cells (p<0.05). Expression of TLR2, TLR4, and TLR8 was increased in CTC positive patients, whereas TLR3 expression was decreased in the dendritic cell population.

Comparative analysis of innate immune system function in metastatic breast, colorectal, and prostate cancer patients with circulating tumor cells.

In recent years, circulating tumor cells (CTCs) in metastatic cancer patients have been found to be a promising biomarker to predict overall survival and tumor progression in these patients. A relatively high number of CTCs has been correlated with disease progression and poorer prognosis. This study was designed to assess innate immune system function, known to be responsible for the immune defense against developing neoplasms, in metastatic cancer patients with CTCs. Our aim is to provide a link between indication of poorer prognosis, represented by the number of CTCs to the cytotoxic activity of natural killer cells, an important component of the innate immune system, and to represent a promising expanded approach to management of metastatic cancer patients with CTCs. Seventy-four patients, with metastatic breast, colorectal, or prostate cancer, were recruited for this study. Using a flow cytometric assay, we measured natural killer (NK) cell cytotoxicity against K562 target cells; and CTCs were enumerated using the CellSearch System. Toll-like receptors 2 and 4 expression was also determined by flow cytometry. We found that within each of our three metastatic cancer patient groups, NK cell cytotoxic activity was decreased in patients with a relatively high number of CTCs in peripheral blood compared to patients with a relatively low number of CTCs. In the breast and prostate cancer group, patients with CTCs greater than 5 had decreased NK cell cytotoxicity when compared to patients with less than 5 CTCs. In the colorectal cancer group, we found that 3 or more CTCs in the blood was the level at which NK cell cytotoxicity is diminished. Additionally, we found that the toll-like receptors 2 and 4 expression was decreased in intensity in all the metastatic cancer patients when compared to the healthy controls. Furthermore, within each cancer group, the expression of both toll-like receptors was decreased in the patients with relatively high number of CTCs, i.e. greater than 5 for the breast and prostate cancer group and greater than 3 for the colorectal cancer group, compared to the patients with relatively low number, i.e. less than 5 or 3, respectively. Treatment options to increase NK cell cytotoxic activity should be considered in patients with relatively high numbers of CTCs.

Circulating tumor cells (CTCs) from metastatic breast cancer patients linked to decreased immune function and response to treatment.

We aimed to examine the use of circulating tumor cells (CTCs) as an effective measure of treatment efficacy and immune system function in metastatic breast cancer patients. CTCs are believed to be indicators of residual disease and thus pose an increased risk of metastasis and poorer outcomes to those patients who are CTC-positive. We obtained peripheral blood samples from 45 patients previously diagnosed with metastatic disease originating in the breast. Using TLR agonists that bind TLR ligands and upregulate immune effects versus unstimulated cells, we calculated a percent specific lysis using chromium-51 assay to illustrate the functional abilities of patient natural killer (NK) cells. We found those with greater than 5 CTCs per 7.5 mL blood had significantly decreased responses by their immune cells when compared with those patients who had 5 CTCs or less. We furthermore found a correlation between disease progression and CTC-positive patients, indicating that those who have a positive test should be closely monitored by their clinician. CTCs represent an exciting new clinical opportunity that will ideally utilize their low invasiveness and quick turnaround time to best benefit clinical scenarios.

The changing face of phase 1 cancer clinical trials: new challenges in study requirements.

Phase 1 studies in cancer have changed in recent years. Now, with the advent of new, less toxic, targeted agents, more patients may be candidates for new drug studies earlier in the course of their disease. It is to the advantage of the members of the oncology community to know more regarding the details and requirements for participation in early-phase clinical trials so they can advocate for their patients and help them decide when such trials may be an appropriate choice. To examine the work intensity of early phase cancer clinical trials, the authors of this report compared the study requirements of phase 1 and 2 protocols. Five parameters were studied as a surrogate of study complexity-the number of physical examinations, vital sign determinations, electrocardiograms (ECGs), nonpharmacokinetic laboratory tests, and pharmacokinetic (PK) sampling-in the first 4 weeks of protocol in 90 studies (49 phase 1 studies and 41 phase 2 studies). From July 2004 through March 2007, there were 49 phase 1 trials in the phase 1 Program, 9 phase 2 studies that were conducted by physicians appointed in that program, and 32 phase 2 trials with accessible data in the Department of Thoracic/Head & Neck Medical Oncology. In the phase 1 trials versus the phase 2 trials, there were significantly more (P < .05) physical examinations (mean +/- standard error, 3.16 +/- 0.24 vs 2.22 +/- 0.13), vital sign determinations (5.63 +/- 0.61 vs 2.80 +/- 0.26), ECGs (4.36 +/- 1.16 vs 0.80 +/- 0.17), nonpharmacokinetic laboratory tests (18.08 +/- 1.31 vs 10.12 +/- 0.65), and PK sampling (15.14 +/- 1.79 vs 1.02 +/- 0.53). These values also differed significantly (P < .005 for each) when the median values were compared in nonparametric tests. Although both phase 1 and phase 2 trials had substantial study requirements, those for the phase 1 studies were significantly higher. The successful conduct of early-phase clinical trials requires significant research infrastructure.

Adjuvant biologic therapy for breast cancer.

Breast cancer continues to be a major health problem despite a decrease in mortality rates over the past 2 decades. Although many advances have been made in the treatment of breast cancer, drug therapy for the disease continues to evolve as more is learned about cell biology and cellular signaling pathways. The development of targeted agents offers the hope of new therapies with better efficacy and tolerability. Biologic therapy has been a cornerstone of targeted therapy for the treatment of advanced breast cancer and is now entering the adjuvant arena. This review summarizes the results of several adjuvant studies and discusses future directions for breast cancer biotherapy.