Circulating DNA in the neoadjuvant setting of early stage colon cancer.

BACKGROUND: While circulating tumour (ct)DNA is an indicator of minimal residual disease and negative prognostic factor in stage II-III colon cancer, no study has ever analysed the value of this biomarker in colon cancer patients treated with neoadjuvant chemotherapy. We sought to fill this gap by using prospectively collected plasma samples from 80 stage III colon cancer patients, receiving one cycle of neoadjuvant FOLFOX followed by surgery +/- adjuvant FOLFOX in the PePiTA trial. MATERIAL AND METHODS: Samples were collected at baseline, 2 weeks and surgery. NPY and WIF1 were selected as universal methylation markers for ctDNA, and analysed with ddPCR technology. ROC curves were applied for cut-off points, and outcome measures included 5-year disease-free survival (DFS) and 6-year overall survival (OS). RESULTS: After a median follow-up of 52.5 months, baseline circulating-free (cf) DNA was an independent prognostic factor for DFS (HR 3.35, 95% CI: 1.15-9.77, p = .03), and a trend towards a similar association was observed for relative cfDNA changes between baseline and surgery (HR 2.57, 95% CI: 0.94-7.05, p = .07). Among 60 ctDNA assessable patients, 25 (42%) had detectable ctDNA at baseline. While detection of ctDNA at any pre-operative timepoint was not associated with outcome, patients with ctDNA increase (change of the worst trending methylation marker ≥11%, or mean ctDNA change of NPY and WIF1 ≥ 0%) between baseline and surgery showed a trend towards worse 5-year DFS (HR 3.66, 95% CI: 0.81-16.44, p = .09). CONCLUSION: This is the first study of ctDNA in the neoadjuvant setting of early-stage colon cancer. Results are hypothesis-generating and should be confirmed in larger series.

Fortnightly or fractionated weekly docetaxel-cisplatin-5-FU as first-line treatment in advanced gastric and gastroesophageal junction adenocarcinoma: The randomized phase II DoGE study.

BACKGROUND: While docetaxel/cisplatin/5-fluorouracil (DCF) outperforms CF in first-line gastric adenocarcinoma, toxicity remains an issue. METHODS: This multicenter phase II trial randomized chemonaïve metastatic gastric adenocarcinoma patients to fractionated weekly DCF (D 40 mg/m2 , C 35 mg/m², F 1800 mg/m² over 24 h, on days 1 and 8 every 3 weeks, arm (1) or fortnightly DCF (D 50 mg/m2 , C 50 mg/m², F 2000 mg/m² over 48 h every 2 weeks, arm (2). Prophylactic granulocyte colony-stimulating factor (G-CSF) was not allowed. The primary endpoint was the rate of febrile neutropenia within the first six treatment weeks (early FN). RESULTS: A total of 106 eligible patients were recruited. The early and overall FN rates were 9.5% and 17% in arm 1, respectively, and 5.9% and 8% in arm 2, respectively. Grade ≥3 toxicities occurred in 81% of patients in arm 1 and 90% of patients in arm 2, the most common being neutropenia (33% vs. 61%), fatigue (27% vs. 25%), vomiting (21% vs. 12%), anorexia (19% vs. 18%), and diarrhea (17% vs. 10%). Median progression-free survival and overall survival were 5.1 (95% CI, 3.2-6.5) and 8.2 months (95% CI, 6.0-14.5), respectively, in arm 1 and 5.2 (95% CI, 3.0-6.9) and 11.9 months (95% CI, 7.4-15.9), respectively, in arm 2. CONCLUSIONS: Fractionated weekly and fortnightly DCF regimens are associated with a low risk of early FN, and a better hematological toxicity profile as compared to historical DCF without compromising efficacy. Both regimens offer greater convenience removing the need for systematic use of prophylactic G-CSF.

Which Factors Predict Overall Survival in Patients With Metastatic Castration-Resistant Prostate Cancer Treated With Abiraterone Acetate Post-Docetaxel?

BACKGROUND: Abiraterone acetate (AA) increases overall survival (OS) in patients with metastatic castration-resistant prostate cancer (mCRPC) previously treated with docetaxel. However, survival time varies substantially between individuals. Our goal was to identify prognostic factors that better estimate OS. MATERIALS AND METHODS: This is a retrospective multicentric analysis of 368 patients with mCRPC starting AA with prednisone after docetaxel. Cox proportional hazards statistics were applied. A multivariate model was constructed based on significant univariate predictors by using a manual stepwise forward and backward selection strategy. Model performance was determined by using receiver operating characteristic (ROC) curves. RESULTS: Univariate analysis identified 20 significant OS predictors. A multivariate model was constructed, based on 220 patients, incorporating 5 independent risk factors for decreased OS at the time of AA initiation: hemoglobin < 12 g/dL (hazard ratio [HR] 2.02), > 10 metastases (HR 1.80), ECOG performance status ≥ 2 (HR 1.88), radiographic progression (HR 1.50), and time since diagnosis < 90 months (HR 1.66, all P < .05). Patients were stratified into 3 groups: good (0-2 risk factors, median OS 22.6 months), intermediate (3 risk factors, median OS 13.9 months), and poor prognosis (4-5 risk factors, median OS 6.2 months). The area under the ROC curve based on the event "death by the time of median OS (13.3 months)" was 0.736 (95% confidence interval 0.670-0.803). CONCLUSION: We identified 5 readily available risk factors independently associated with decreased OS. The resulting model may be used for patient counseling in daily clinical practice, as well as patient stratification in clinical trials.

Abiraterone acetate post-docetaxel for metastatic castration-resistant prostate cancer in the Belgian compassionate use program.

BACKGROUND: Abiraterone acetate (AA) is licensed for treating metastatic castration-resistant prostate cancer (mCRPC). Real-world data on oncological outcome after AA are scarce. The current study assesses efficacy and safety of AA in mCRPC patients previously treated with docetaxel who started treatment during the Belgian compassionate use program (January 2011-July 2012). PATIENTS AND METHODS: Records from 368 patients with mCRPC from 23 different Belgian hospitals who started AA 1000mg per day with 10mg prednisone or equivalent were retrospectively reviewed (September 2013-December 2014). Prostate-specific antigen (PSA) response (decrease≥50%), time to PSA progression (increase>50% over PSA nadir in case of PSA response/>25% in absence of PSA response), time to radiographic progression (on bone scans or for soft tissue lesions using Response Evaluation Criteria In Solid Tumors 1.1), overall survival and adverse event rate (Common Terminology Criteria for Adverse Events v4.03) were analyzed. Kaplan-Meier statistics were applied. RESULTS: Overall, 92 patients (25%) had an Eastern Cooperative Oncology Group performance status≥2. Median age was 73 years, median PSA was 103ng/dl. PSA response was observed in 131 patients (37.4%). Median time to PSA and radiographic progression was 4.1 months (95% CI: 3.6-4.6) and 5.8 months (5.3-6.4), respectively. Median overall survival was 15.1 months (13.6-16.6). Most common grade 3 to 4 adverse events were anemia (13.9%), hypokalemia (7.3%), fatigue (6.8%), and pain (6.3%). Median duration of AA treatment was 5.3 months (interquartile range: 2.8-10.3). The main study limitation is its retrospective design. CONCLUSIONS: These real-world data on post-docetaxel AA efficacy are in line with the COU-AA-301 trial. Importantly, incidence of severe anemia and hypokalemia is up to 50% higher than reported in previous studies.

Phase I study of sorafenib in combination with docetaxel and prednisone in chemo-naïve patients with metastatic castration-resistant prostate cancer.

PURPOSE: We performed a dose-escalation study to investigate the safety of sorafenib in combination with docetaxel and prednisone in chemo-naïve patients with metastatic castration-resistant prostate cancer (mCRPC). METHODS: Six patients were included per dose level. Following docetaxel infusion on day 1 (75 mg/m(2)/q3 weeks), sorafenib was administered at 200 mg BID on days 2-19 (dose level 1), at 200 mg BID on days 1-21 (dose level 2), at 400 mg BID on days 2-19 (dose level 3), at 400 mg BID on days 1-21 (dose level 4). Maximal tolerated dose (MTD) was exceeded if ≥2 patients experienced dose-limiting toxicities (DLT) during cycle 1. The recommended phase 2 dose for sorafenib was defined as one dose level below MTD. If MTD was not reached, the highest feasible dose would be selected to treat an expanded cohort to confirm safety. RESULTS: Two DLTs were observed during sorafenib dose-escalation consisting of grade 4 febrile neutropenia (dose level 2) and grade 3 hand-foot syndrome (HFS) (dose level 3). Our pharmacokinetic results showed an increased exposure to docetaxel across all dose levels during sorafenib comedication. The main grade ≥3 toxicities were neutropenia (35 %), HFS (27 %), and febrile neutropenia (19 %). The prostate-specific antigen (PSA) response rate was 74 %. Median overall survival was 25.2 months. CONCLUSION: Three-weekly docetaxel and prednisone could be combined with sorafenib at 400 mg BID on days 1-21 without reaching MTD. However, we observed a pharmacokinetic interaction between sorafenib and docetaxel, associated with significant toxicities, raising concerns about the safety of this combination in mCRPC.

Prospective randomized study comparing docetaxel, estramustine, and prednisone with docetaxel and prednisone in metastatic hormone-refractory prostate cancer.

PURPOSE: To assess the efficacy and toxicity of the addition of estramustine to docetaxel (D) for the treatment of metastatic hormone-refractory prostate cancer. PATIENTS AND METHODS: One hundred fifty patients were randomly assigned to D alone (35 mg/m(2) on days 2 and 9, every 3 weeks) or D in combination with estramustine (D/E; 280 mg orally three times a day on days 1 to 5 and 8 to 12, every 3 weeks). All patients received prednisone (10 mg/d). The primary end point was prostate-specific antigen (PSA) response rate, which was defined as a decrease in PSA > or = 50% from baseline. The study was powered to test the hypothesis that D/E would improve the PSA response rate by 25%. RESULTS: The PSA response rate was not statistically different between the two groups. PSA of less than 4 ng/mL occurred in 29 (41%) of 71 patients receiving D/E and in 17 (25%) of 69 patients receiving D (P = .05). No significant differences were found for median time to PSA progression (D/E, 6.9 months; D, 7.3 months) or median overall survival time (D/E, 19.3 months; D, 21 months). More patients had at least one grade 3 or 4 toxicity with D/E (45%) compared with D (21%; P = .005), mainly as a result of grade 3 or 4 GI toxicity (P = .05). Serious adverse events were more frequent with D/E (n = 20) than with D (n = 9; P = .04). CONCLUSION: The addition of estramustine to weekly D does not provide any clinically relevant advantage. Both regimens are well tolerated, although the toxicity profile favors D without estramustine.