Increased circulating tumor DNA as a noninvasive biomarker of early treatment response in patients with metastatic ovarian carcinoma: A pilot study.

Detection of circulating tumor DNA is a new noninvasive technique with potential roles in diagnostic, follow-up, and prognostic evaluation of patients with many types of solid tumors. We aimed to evaluate the role of circulating tumor DNA in the setting of metastatic ovarian carcinoma. A prospective cohort of patients with metastatic ovarian cancer who were referred to systemic therapy was enrolled. Blood samples were collected before the start of treatment and monthly thereafter for 6 months. Circulating tumor DNA was quantified by real-time quantitative reverse transcription polymerase chain reaction of different lengths of Arthrobacter luteus elements as described by Umetani et al. A total of 11 patients were included, 2 for primary disease and 9 for recurrent disease. After the first cycle of chemotherapy, patients whose circulating tumor DNA levels increased from baseline were more likely to respond to chemotherapy than those whose circulating tumor DNA levels did not increase (p = 0.035). Furthermore, patients whose circulating tumor DNA levels rose after the first cycle of chemotherapy also had improved disease-free survival compared to those whose circulating tumor DNA levels did not increase (p = 0.0074). We conclude that the increase in circulating tumor DNA values collected in peripheral blood after the first cycle of systemic treatment in patients with advanced ovarian cancer is associated with an early response to systemic treatment and correlates with superior disease-free survival in this population. Circulating tumor DNA might be a specific, noninvasive, and cost-effective new biomarker of early response to systemic treatment in these patients.

The feasibility of dexamethasone omission in weekly paclitaxel treatment for breast cancer patients.

OBJECTIVES: Patients with breast cancer who receive weekly paclitaxel therapy may experience deleterious effects associated with prophylactic dexamethasone use for 12 consecutive weeks. Approximately 90% of paclitaxel hypersensitivity reactions (HSRs) occur within the first 10 to 15 min of the first two infusions. We investigated the feasibility of dexamethasone withdrawal between weeks 3 and 12 (W3 and W12) in early stage breast cancer patients treated with weekly paclitaxel at the standard dose (80 mg/m2). METHODS: All patients received intravenous prophylaxis of dexamethasone 20 mg, ranitidine 50 mg, and diphenhydramine 50 mg in the first 2 weeks (W1 and W2) of treatment. Provided that no serious (G3/G4) HSRs events occurred, dexamethasone was omitted between W3 and W12, while ranitidine and diphenhydramine were continued. The primary end point was the incidence of any grade HSRs during the treatment period, and the secondary end points were quality of life and weight changes. RESULTS: Twenty-five patients were included in the study, and 300 infusion cycles of paclitaxel were evaluated for HSRs. The overall incidence of HSRs was 0.6% (2 events), and both of these events occurred in the first week. There were no incidents of serious HSRs or anaphylaxis and no G3 or G4 toxicities. Scores from the EORTC QLQ-C30 questionnaire did not change significantly for the global health status/quality of life scale or for the symptoms scales, although changes in scores differed significantly for the functional scales. There were no clinically relevant weight changes during the treatment period. CONCLUSIONS: Dexamethasone withdrawal from W3 to W12 in early stage breast cancer patients treated with weekly paclitaxel is feasible. The incidence of all grades of HSRs was comparable to that reported in trials with dexamethasone for 12 consecutive weeks, and no serious events (G3/G4) occurred. Studies with larger sample sizes are needed to confirm our results which are important, especially for patients for whom corticosteroids are contraindicated.