PARP Inhibitor for Neoadjuvant Therapy in HER2-Negative Breast Cancer: A Systematic Review and Meta-Analysis of Efficacy and Safety.

Poly-ADP ribose polymerase inhibitor (PARPi) is approved for HER2-negative advanced breast cancer with BRCA1/2 mutation. In recent years, many studies have explored the application of PARPi in neoadjuvant therapy, but failed to reach a unified conclusion. PubMed, Clinicaltrials.gov, Cochrane CENTRAL, Embase, and key oncological meetings for trials were searched for studies reporting neoadjuvant regimens with PARPi in HER2-negative breast cancer. Pathological complete response (pCR), residual cancer burden (RCB), breast-conservation surgery rate (BCSR), clinical response, and adverse events were extracted and pooled in a meta-analysis using the Mantel Haenszel random/fixed effects model. Subgroup analyses of pCR were conducted according to BRCA1/2 status, and hormone receptor (HR) status. Five studies (N = 1223) were included, the addition of PARPi to neoadjuvant regimens significantly increased pCR rates (HR 1.45, 95%CI 1.09-1.92, P = .01, I2 = 86%). In subgroup analysis, the addition of PARPi increased the pCR rate both in HR-positive (n = 383) and HR-negative (n = 431) subgroups, which showed a dominant effect of PARPi regardless of HR status (HR 2.07, 95%CI 1.33-3.23, P = .001, I2 = 0%; HR 1.85, 95%CI 1.39-2.26, P < .0001, I2 = 0%, respectively). However, when we performed a subgroup analysis based on the status of BRCA1/2, no further benefit for PARPi was found. Adverse reactions were generally tolerable. Other outcome indexes, including RCB, clinical response, BCSR, and PARPi did not show a clinical benefit. Regardless of BRCA1/2 status, PARPi in neoadjuvant therapy, can improve the pCR rate of HER2-negative breast cancer, especially in HR-positive patients. Thus, we should have performed larger randomized trials and provided a stronger evidence-based basis.

Comprehensive review of solid tumor bone marrow metastasis.

Bone marrow metastasis (BMM) of solid tumors refers to a group of diseases that originate from non-hematopoietic malignant tumor cells invading the bone marrow (BM) through complex metastatic patterns. If BMM identification is delayed, the disease will rapidly develop into disseminated carcinogenesis of the BM, which manifests as a series of hematological disorders and microangiopathic hemolytic anemia, leading to serious life-threatening conditions. Although the study of solid tumor BMM is receiving increasing attention, study remains limited, and most descriptions are derived from case reports. Currently, clinicians have insufficient understanding of BMM, and BMM occurrence is often not recognized early or treated effectively, resulting in high mortality rates. In this article, we review the epidemiology, molecular mechanisms, clinical diagnosis, treatment, and prognosis of solid tumor BMM.