Dynamic Changes of Post-Radiotherapy Plasma Epstein-Barr Virus DNA in a Randomized Trial of Adjuvant Chemotherapy Versus Observation in Nasopharyngeal Cancer.

PURPOSE: To study the dynamic changes in plasma Epstein-Barr virus (pEBV) DNA after radiotherapy in nasopharyngeal cancer (NPC). EXPERIMENTAL DESIGN: We conducted a randomized controlled trial of adjuvant chemotherapy versus observation in patients with NPC who had detectable pEBV DNA at 6 weeks post-radiotherapy. Randomized patients had a second pEBV DNA checked at 6 months post-randomization. The primary endpoint was progression-free survival (PFS). RESULTS: We prospectively enrolled 789 patients. Baseline post-radiotherapy pEBV DNA was undetectable in 573 (72.6%) patients, and detectable in 216 (27.4%) patients, of whom 104 (13.2%) patients were eligible for randomization to adjuvant chemotherapy (n = 52) versus observation (n = 52). The first post-radiotherapy pEBV DNA had a sensitivity of 0.48, specificity of 0.81, area under receiver-operator characteristics curve (AUC) of 0.65, false positive (FP) rate of 13.8%, and false negative (FN) rate of 14.4% for disease progression. The second post-radiotherapy pEBV DNA had improved sensitivity of 0.81, specificity of 0.75, AUC of 0.78, FP rate of 14.3%, and FN rate of 8.1%. Patients with complete clearance of post-radiotherapy pEBV DNA (51%) had survival superior to that of patients without post-radiotherapy pEBV DNA clearance (5-year PFS, 85.5% vs. 23.3%; HR, 9.6; P < 0.0001), comparable with patients with initially undetectable post-radiotherapy pEBV DNA (5-year PFS, 77.1%), irrespective of adjuvant chemotherapy or observation. CONCLUSIONS: Patients with NPC with detectable post-radiotherapy pEBV DNA who experienced subsequent pEBV DNA clearance had superior survival comparable with patients with initially undetectable post-radiotherapy pEBV DNA. Post-radiotherapy pEBV DNA clearance may serve as an early surrogate endpoint for long-term survival in NPC.

Controversies and consensus of neoadjuvant chemotherapy in soft-tissue sarcomas.

Together with surgery and radiotherapy, systemic treatment with cytotoxic chemotherapy and molecular targeted agents is one of the main therapeutic pillars in the treatment of soft-tissue sarcomas and is the mainstay of treatment in patients with advanced or metastatic disease. Unlike other more common malignancies such as breast and colorectal cancer, the role of chemotherapy when used in the adjuvant setting in soft-tissue sarcomas is less well defined. Results from prior studies have been conflicting, in part due to the heterogeneity and rarity of the disease, and large-scale meta-analysis has been performed to address this issue. Neoadjuvant chemotherapy, defined as the use of chemotherapy before definitive treatment with surgery or radiotherapy, has distinct theoretical and practical advantages, which can potentially be beneficial to the patient. However, the currently available evidence to support its use is even more scarce. In this review article, we describe the current established data behind the use of adjuvant chemotherapy in selected patients with localised soft-tissue sarcomas and, through extrapolation of available data, discuss the potential role of it when used in the upfront setting.