Identifying the optimal candidates for locoregional radiation therapy in patients with de novo metastatic nasopharyngeal carcinoma.

BACKGROUND: To evaluate the value of locoregional radiation therapy (LRRT) in de novo metastatic nasopharyngeal carcinoma (mNPC) and identify suitable candidates for additional LRRT after palliative chemotherapy (PCT). METHODS: Patients with de novo mNPC received platinum-based chemotherapy for a minimum of four cycles with or without definitive LRRT via intensity-modulated radiation therapy (IMRT) were all candidates for this study. RESULTS: A total of 168 patients were included for this analysis. Additional LRRT was associated with significantly longer median OS (69.5 vs. 17.8 months, p < 0.001) when compared with PCT alone. However, this survival benefit of LRRT was only reflected in patients with oligometastatic diseases (90.8 vs. 17 months, p < 0.001), but not for those with polymetastatic disease (p = 0.86). CONCLUSIONS: Additional LRRT after PCT may only improve OS for oligometastatic patients. For patients with polymetastatic disease, intensive systemic treatment such as the combination of immunotherapy and adequate PCT might be necessary.

[Characteristics of carbon storage and its allocation in Erythrophleum fordii plantations with different ages].

Carbon storage and its allocation of 7-, 29- and 32-year-old Erythrophleum fordii plantation ecosystems in Guangxi were studied on the basis of biomass survey. The results showed that the carbon contents in different organs of E. fordii, ranging from 509.0 to 572.4 g x kg(-1), were in the order of stem > branch > root > bark > leaf. No significant differences in carbon content were observed among the shrub, herb and litter layers of the E. fordii plantations with different ages. Carbon content in the soil layer (0-100 cm) decreased with increasing the soil depth, but increased with increasing the stand age. The carbon storage of the arbor layer was 21.8, 100.0 and 121.6 t x hm(-2) for 7-, 29- and 32-year-old stands, respectively, and the order of carbon storage allocation in different organs was same as the order of carbon content. The 7-, 29- and 32-year-old E. fordii plantation ecosystems stored carbon at 132.6, 220.2 and 242.6 t x hm(-2), respectively. The arbor layer and soil layer were the main carbon pools, accounting for more than 97% of carbon storage in the ecosystem. Carbon storage allocation increased in arbor layer but decreased in soil layer with increasing the stand age. The influence of stand age on carbon storage allocation in shrub, herb and litter layers did not show a obvious regular pattern.