Acquired mutations are pervasive across normal tissues. However, our understanding of the processes that drive transformation of certain clones to cancer is limited. Here we study this phenomenon in the context of clonal hematopoiesis (CH) and the development of therapy-related myeloid neoplasms (tMN). We find mutations are selected differentially based on exposures. Mutations in ASXL1 are enriched in current or former smokers, whereas cancer therapy with radiation, platinum and topoisomerase II inhibitors preferentially selects for mutations in DNA damage response (DDR) genes ( TP53, PPM1D, CHEK2 ). Sequential sampling provides definitive evidence that DDR clones outcompete other clones when exposed to certain therapies. Among cases where CH was previously detected, the CH mutation was present at tMN diagnosis. We identify the molecular characteristics of CH that increase risk of tMN. The increasing implementation of clinical sequencing at diagnosis provides an opportunity to identify patients at risk of tMN for prevention strategies.

Objectives To evaluate the risk of venous thromboembolic events associated with the use of progestin-only contraception and whether that risk differs with the mode of drug delivery (oral, intrauterine, or depot injection).Design Systematic review and meta-analysis of randomised controlled trials and observational studies.Data sources Pubmed, Embase, Cochrane Library, and reference lists of relevant reviews.Study selection Randomised controlled trials and case-control, cohort, and cross sectional studies with venous thromboembolic outcome for progestin-only contraception reported relative to a non-hormone comparator group.Data extraction Data were extracted by two independent investigators, and consensus for inclusion was reached after assessment by additional investigators.Results Among the 2022 unique references identified by all searches, eight observational studies fulfilled inclusion criteria. A total of 147 women across all studies were diagnosed with a venous thromboembolic event while taking progestin-only contraception, and the summary measure for the adjusted relative risk of a venous thromboembolic episode for users versus non-users of a progestin-only contraceptive was, based on the random effects model, 1.03 (95% CI 0.76 to 1.39). Subgroup analysis confirmed there was no association between venous thromboembolic risk and progestin-only pills (relative risk 0.90 (0.57 to 1.45)) or a progestin intrauterine device (0.61 (0.24 to 1.53)). The relative risk of a venous thromboembolic event for users of an injectable progestin versus non-users was 2.67 (1.29 to 5.53).Conclusions Published data assessing the risk of venous thromboembolism in women prescribed progestin-only contraception are limited. In this meta-analysis of eight observational studies, the use of progestin-only contraception was not associated with an increased risk of venous thromboembolism compared with non-users of hormonal contraception. The potential association between injectable progestins and thrombosis requires further study.

SUMMARY Elevated levels of circulating tissue factor-bearing microparticles (TFMP) have been associated with an increased risk of developing venous thromboembolism (VTE) in cancer patients. We performed a randomized phase II study to evaluate the cumulative incidence of VTE in advanced cancer patients with lower levels of TFMP not receiving thromboprophylaxis and those with higher levels of circulating TFMP randomized to enoxaparin or observation. The cumulative incidence of VTE at 2 months in the higher TFMP group randomized to enoxaparin (N=23) was 5.6% while the higher TFMP group observation arm (N=11) was 27.3% (Gray test P=0.06). The cumulative incidence of VTE in the low TFMP was 7.2% (N=32). No major haemorrhages were observed in the enoxaparin arm. The median survival for patients with higher levels of TFMP followed by observation was 11.8 months compared with 17.8 months on enoxaparin (P=0.58). In a prospective randomized trial, increased numbers of circulating TFMP detected by impedance flow cytometry identified cancer patients with a high incidence of VTE. Enoxaparin demonstrated a clear trend towards reducing the rate of VTE in patients with elevated levels of TFMP, with an overall rate of VTE similar in magnitude to the lower TFMP group.

PURPOSE Chemotherapy-induced thrombocytopenia (CIT) leads to delay or reduction in cancer treatment. There is no approved treatment. METHODS We conducted a phase II randomized trial of romiplostim versus untreated observation in patients with solid tumors with CIT. Before enrollment, patients had platelets less than 100,000/μL for at least 4 weeks, despite delay or dose reduction of chemotherapy. Patients received weekly titrated romiplostim with a target platelet count of 100,000/μL or more, or were monitored with usual care. The primary end point was correction of platelet count within 3 weeks. Twenty-three patients were treated in a randomization phase, and an additional 37 patients were treated in a single-arm, romiplostim phase. Resumption of chemotherapy without recurrent CIT was a secondary end point. RESULTS The mean platelet count at enrollment was 62,000/μL. In the randomization phase, 14 of 15 romiplostim-treated patients (93%) experienced correction of their platelet count within 3 weeks, compared with one of eight control patients (12.5%; P < .001). Including all romiplostim-treated patients (N = 52), the mean platelet count at 2 weeks of treatment was 141,000/μL. The mean platelet count in the eight observation patients at 3 weeks was 57,000/μL. Forty-four patients who achieved platelet correction with romiplostim resumed chemotherapy with weekly romiplostim. Only three patients (6.8%) experienced recurrent reduction or delay of chemotherapy because of isolated CIT. CONCLUSION This prospective trial evaluated treatment of CIT with romiplostim. Romiplostim is effective in correcting CIT, and maintenance allows for resumption of chemotherapy without recurrence of CIT in most patients.

Background Low-molecular weight heparin (LMWH) has been the standard of care for treatment of venous thromboembolism (VTE) in patients with cancer. Rivaroxaban was approved in 2012 for the treatment of pulmonary embolism (PE) and deep vein thrombosis (DVT), but no prior studies have been reported specifically evaluating the efficacy and safety of rivaroxaban for cancer-associated thrombosis (CAT). Under a Quality Assessment Initiative (QAI), we established a Clinical Pathway to guide rivaroxaban use for CAT and now report a validation analysis of our first 200 patients. Methods A 200 patient cohort with CAT (PE or symptomatic, proximal DVT), whose full course of anticoagulation was with rivaroxaban, were accrued. In competing risk analysis, primary endpoints at six months included new or recurrent PE or symptomatic proximal lower extremity DVT, major bleeding, clinically-relevant non-major bleeding leading to discontinuation of rivaroxaban, or death. Findings In competing risk analysis, the 6 months cumulative incidence of new or recurrent VTE was 4.4% (95% CI=1.4–7.4%), major bleeding was 2.2% (95% CI=0–4.2%) and all-cause mortality 17.6% (95% CI=11.7–23.0%). Interpretation In this cohort of 200 patients with active cancer and CAT the rates of new or recurrent VTE and major bleeding were comparable to the cancer subgroup analysis from the EINSTEIN studies. The results of our Clinical Pathway provide guidance on Rivaroxaban use for treatment of CAT, and suggest that safety and efficacy is preserved, compared with past-published experience with LMWH.

Clonal hematopoiesis (CH) is frequent in cancer patients and associated with increased risk of therapy related myeloid neoplasms (tMN). To define the relationship between CH, oncologic 90 therapy, and tMN progression, we studied 24,439 cancer patients. We show that previously treated patients have increased rates of CH, with enrichment of mutations in DNA Damage Response (DDR) genes (TP53, PPM1D, CHEK2). Exposure to radiation, platinum and topoisomerase II inhibitors have the strongest association with CH with evidence of dose-dependence and genetreatment interactions. We validate these associations in serial sampling from 525 patients and 95show that exposure to cytotoxic and radiation therapy imparts a selective advantage specifically in hematopoietic cells with DDR mutations. In patients who progressed to tMN, the clone at CH demarcated the dominant clone at tMN diagnosis. CH mutational features predict risk of therapyrelated myeloid neoplasm in solid tumor patients with clinical implications for early detection and treatment decisions. 100

Four target-specific oral anticoagulants (TSOA's) have been compared to a vitamin K antagonist for the treatment of acute venous thromboembolism (VTE): dabigatran (D), rivaroxaban (R), apixaban (A) and edoxaban (E). We performed an indirect comparison of the TSOA's, based on the six phase III trials identified (RE-COVER I, RE-COVER II, EINSTEIN-DVT, EINSTEIN-PE, AMPLIFY and Hokusai-VTE). There was no statistically significant difference in risk of recurrent VTE or all-cause mortality between the TSOA's. For major bleeding, the RR of an event was 0.42 (95% CI 0.21-0.87, p = 0.02) for A versus D, compared with 0.57 (95% CI 0.29-1.15, p = 0.12) for A versus R, 0.37 (95% CI 0.19-0.73, p < 0.001) for A versus E, 0.74 (95% CI 0.42-1.30, p = 0.30) for R versus D, 0.64 (95% CI 0.38-1.08, p = 0.10) for R versus E and 1.15 (95% CI 0.66-2.00, p = 0.62) for E versus D. For the composite endpoint of major or clinically relevant nonmajor bleeding, the RR was 0.71 (95% CI 0.53-0.96, p = 0.02) for A versus D, 0.47 (95% CI 0.37-0.61, p < 0.001) for A versus R, 0.54 (95% CI 0.42-0.70, p < 0.001) for A versus E, 1.50 (95% CI 1.17-1.92, p = 0.001) for R versus D, 1.15 (95% CI 0.95-1.39, p = 0.16) for R versus E and 1.31 (95% CI 1.02-1.68, p = 0.04) for E versus D. Overall, apixaban appears to be associated with a lower risk of bleeding than the other TSOA's. This analysis may be helpful to the clinician in trying to balance risk versus benefit in selecting a new anticoagulant. A dedicated randomized trial directly comparing the new agents would be required to confirm these results.

Romiplostim resulted in improvement in platelet counts, allowing resumption of chemotherapy without recurrence of dose-limiting CIT. No treatment-related toxicity was observed, but this would need to be confirmed in a larger, prospective trial. Our series differs from prior studies in that we selected only those patients who had already demonstrated persistent thrombocytopenia, and we continued weekly romiplostim during chemotherapy. Romiplostim may be a safe and effective treatment for CIT.