ABSTRACT
The relatively high prevalence of alterations in the homologous recombination repair (HRR) pathway described in advanced prostate cancer provides a unique opportunity to develop therapeutic strategies that take advantage of the decreased tumor ability to repair DNA damage. Poly ADP-ribose polymerase (PARP) inhibitors have been demonstrated to improve the outcomes of metastatic castration-resistant prostate cancer (mCRPC) patients with HRR defects, particularly in those with BRCA1/2 alterations. To expand the benefit of PARPi to patients without detectable HRR alterations, multiple studies are addressing potential synergies between PARP inhibition (PARPi) and androgen receptor pathway inhibitors (ARSi), radiation, radioligand therapy, chemotherapy, or immunotherapy, and these strategies are also being evaluated in the hormone-sensitive setting. In this review, we summarize the development of PARPi in prostate cancer, the potential synergies, and combinations being investigated as well as the future directions of PARPi for the management of the disease.
Development of PARP inhibitors in advanced prostate cancer Alterations in the mechanisms responsible for repairing damaged DNA are frequently altered in advanced prostate cancer. This provides a unique opportunity to develop therapies that exploit the decreased ability of these prostate tumours to repair DNA. Poly ADP-ribose polymerase (PARP) inhibitors have been successfully used to treat other tumor types with similar deficiencies and recently, multiple studies have demonstrated its efficacy also in prostate cancer, particularly in tumors with BRCA1/2 alterations. To expand the benefit of PARPi to patients without detectable DNA repair alterations, multiple studies are addressing potential synergies between PARP inhibition (PARPi) and androgen receptor pathway inhibitors (ARSi), radiation, radiopharmaceuticals, chemotherapy and immunotherapy in different disease stages. In this review, we summarize the development of PARPi in prostate cancer, the potential synergies and combinations being evaluated as well as the future directions of PARPi for the management of the disease.
ABSTRACT
BACKGROUND: Systemic treatment with immune combinations is the gold standard for metastatic renal cell carcinoma (mRCC) worldwide. The systemic immune-inflammation index (SII) is a prognostic marker for several types of malignant neoplasms, including mRCC, in the era of tyrosine kinase inhibitor (TKI) treatment. Data regarding the prognostic value of the SII in patients with mRCC treated with immunotherapy are scarce and controversial.⯠METHODS: We retrospectively collected the data of patients with mRCC from 56 centers in 18 countries. SII (Platelet × Neutrophil/Lymphocyte count) was calculated prior to the first systemic treatment and cut-off was defined by a survival receiver operating characteristic (ROC) analysis. The primary objective of our retrospective study was to assess the outcomes of patients treated with first-line immunotherapy.⯠RESULTS: Data from 1034 mRCC patients was collected and included in this analysis. The SII cut-off value was 1265. After a follow-up of 26.7 months, and the overall survival (OS) and progression-free survival (PFS) were 39.8 and 15.7 months, respectively. According to SII (low vs. high), patients with low-SII had longer OS (55.7 vs. 22.2 months, P < .001), better PFS (20.8 vs. 8.5 months, P < .001), and higher overall response rate (52 vs. 37%, P = .033). CONCLUSION: A high SII is associated with poor oncological outcomes in patients with mRCC. SII could be an easily accessible prognostic indicator for use in clinical practice.