RESUMO
OBJECTIVE: In this prospective study, we aim to characterize the prognostic value of circulating tumor DNA (ctDNA) by next-generation-sequencing (NGS) in patients undergoing neoadjuvant chemotherapy (NAC) for pancreatic ductal adenocarcinoma (PDAC). SUMMARY BACKGROUND DATA: Circulating tumor DNA is a promising blood-based biomarker that is prognostic in several malignancies. Detection of ctDNA by NGS may provide insights regarding the mutational profiles in PDAC to help guide clinical decisions for patients in a potentially curative setting. However, the utility of ctDNA as a biomarker in localized PDAC remains unclear. METHODS: Patients with localized PDAC were enrolled in a prospective study at Northwestern Medicine between October 2020 and October 2022. Blood samples were collected to perform targeted tumor agnostic NGS utilizing the Tempus x|F 105 gene panel at three timepoints: pre-therapy (at diagnosis), post-NAC, and after local therapy, including surgery. The relationship between ctDNA detection and CA19-9, and the prognostic significance of ctDNA detection were analyzed. RESULTS: 56 patients were included in the analysis. ctDNA was detectable in 48% at diagnosis, 33% post-NAC, and 41% after local therapy. After completion of NAC, patients with detectable ctDNA had higher CA19-9 levels versus those without (78.4 vs. 30.0, P=0.02). The presence of baseline ctDNA was associated with a CA19-9 response; those without ctDNA had a significant CA19-9 response following NAC (109.0 U/mL vs. 31.5 U/mL; P=0.01), while those with ctDNA present at diagnosis did not (198.1 U/mL vs. 113.8 U/mL; P=0.77). In patients treated with NAC, the presence of KRAS ctDNA at diagnosis was associated with and independently predicted worse progression-free-survival. CONCLUSION: This report demonstrates the prognostic value of ctDNA analysis with NGS in localized PDAC. NGS ctDNA is a biomarker of treatment response to NAC. KRAS ctDNA at diagnosis independently predicts worse survival in patients treated with NAC.
RESUMO
Nonrandomized trials suggest that pegfilgrastim, a pegylated granulocyte colony-stimulating factor, could be used in lieu of filgrastim after autologus peripheral blood stem cell transplantation. This phase III, randomized, double-blinded, placebo-controlled trial compared the efficacy, costs, and safety of single-dose pegfilgrastim (single 6 mg dose) versus daily filgrastim (5 microg/kg/day) for this indication. Seventy-eight patients, matched for age, sex, underlying disease, stage, and CD34/kg transplant dose were enrolled. Cytokines were started on day +1 posttransplant and continued to an absolute neutrophil count (ANC) of 5x10(9)/L for 3 days or 10x10(9)/L for 1 day. The median time to neutrophil engraftment (ANC >1.5x10(9)/L for 3 days or 5x10(9)/L for 1 day) was the same in both groups (12 days). No differences in platelet engraftment (11 versus 13 days), number of platelet transfusions (5 versus 4), percent with positive cultures for bacterial pathogens (23% versus 15%), days of fever (1 versus 2), deaths prior to engraftment (1 versus 1), or duration of hospital stay (19 versus 19 days) were seen between the pegfilgrastim and filgrastim groups, respectively. Using the average wholesale price for doses used in this trial, there was a per-patient savings of $961 for the pegfilgrastim group (P < .001). This phase III study failed to demonstrate a difference in time to neutrophil engraftment or any clinical sequelae between pegfilgrastim and filgrastim when given post-APBSCT, with pegfilgrastim achieving a cost savings over filgrastim.