Gravitational Test beyond the First Post-Newtonian Order with the Shadow of the M87 Black Hole.

The 2017 Event Horizon Telescope (EHT) observations of the central source in M87 have led to the first measurement of the size of a black-hole shadow. This observation offers a new and clean gravitational test of the black-hole metric in the strong-field regime. We show analytically that spacetimes that deviate from the Kerr metric but satisfy weak-field tests can lead to large deviations in the predicted black-hole shadows that are inconsistent with even the current EHT measurements. We use numerical calculations of regular, parametric, non-Kerr metrics to identify the common characteristic among these different parametrizations that control the predicted shadow size. We show that the shadow-size measurements place significant constraints on deviation parameters that control the second post-Newtonian and higher orders of each metric and are, therefore, inaccessible to weak-field tests. The new constraints are complementary to those imposed by observations of gravitational waves from stellar-mass sources.

Pathological complete response rates with pertuzumab-based neoadjuvant chemotherapy in breast cancer: A single-center experience.

BACKGROUND: Pertuzumab-based neoadjuvant chemotherapy (NAC) has demonstrated successful pathologic complete response (pCR) rates when administered to patients with human epidermal growth factor receptor 2 (HER2)-positive, locally advanced breast cancer and has become standard of care. This study aimed to identify pCR rates in patients receiving a variety of pertuzumab-based NAC regimens. The effect of the addition of an anthracycline and impact of anthracycline and taxane sequencing on pCR was also assessed. METHODS: A retrospective, single-center review was conducted on patients with operable, human epidermal growth factor receptor 2 (HER2)-positive breast cancer that received one of five pertuzumab-containing NAC regimens followed by definitive surgery. RESULTS: Ninety-six patients were included in the analysis; overall, pCR was attained in 49 patients (51%). Of the 61 patients who received an anthracycline-containing NAC regimen, 30 (49%) attained a pCR. Of the 35 patients who received the non-anthracycline NAC regimen, 19 (54%) attained a pCR; difference in pCR was not statistically significant (p = 0.63). Anthracycline/taxane sequence analysis showed that of the patients attaining pCR with an anthracycline-containing NAC, 77% of patients received the taxane portion upfront (p = 0.17). Relative dose intensity of the anthracycline portion was similar irrespective of treatment sequence. However, relative dose intensity of the taxane portion was decreased with upfront anthracycline administration. CONCLUSION: These findings support current recommendations of adding pertuzumab to established regimens for treatment of locally advanced, HER2-positive, early stage breast cancer. The benefit of adding an anthracycline in the neoadjuvant setting remains unclear. Patients treated with the taxane portion of NAC upfront appeared to have a higher rate of pCR and better relative dose intensity than patients who received the anthracycline portion upfront, but differences were not statistically significant. These findings should be verified in a prospective clinical trial.

The pharmacologic management of multiple myeloma in older adults.

INTRODUCTION: Multiple myeloma is a disease predominately affecting older adults. Pivotal to treating older adults is understanding their physiologic differences compared to younger subjects and how the complexity of therapies has an impact upon this patient population. AREAS COVERED: Herein, the authors address the efficacy of chemotherapy regimens, decision-making for older adults, chemotherapy-associated toxicity and the approach to management. This review focuses on the complex treatment of older multiple myeloma patients and management of treatment-related adverse events. EXPERT OPINION: Balancing efficacy and managing toxicity is a challenge for older myeloma patients. This group is more susceptible to treatment toxicities due to a higher incidence of pre-existing comorbidities and underlying diminished physiologic reserve. Intensive therapies such as autologous hematopoietic cell transplant (AHCT), however, still should be considered for all multiple myeloma patients, including older adults. The continued development of novel therapies and increased use of multi-drug regimens has changed the treatment paradigms yet understanding the complexity of the aging adult in the context of various drugs is warranted.

Endocrine therapy in breast cancer: the neoadjuvant, adjuvant, and metastatic approach.

OBJECTIVES: To review the rationale for endocrine therapy in the neoadjuvant, adjuvant, and metastatic breast cancer setting and to highlight clinical considerations unique to this treatment. DATA SOURCES: Contemporary literature, clinical guidelines, and national statistics. CONCLUSION: Endocrine therapy represents an important strategy in the management of both early and advanced hormone positive breast cancer. Additional research is required to better define the role of neoadjuvant therapy and the optimal duration of treatment. IMPLICATIONS FOR NURSING PRACTICE: Nurses play a pivotal role in the identification and management of endocrine therapy-associated symptoms. Prompt symptom intervention may improve therapy adherence and ultimately, may improve long-term disease outcomes.