The guidelines represent an agreed consensus view of the ILROG steering committee on the use of RT in NHL in the modern era. The roles of reduced volume and reduced doses are addressed,integrating modern imaging with 3-dimensional planning and advanced techniques of RT delivery. In the modern era,combined-modality treatment with systemic therapy is appropriate. A new concept,involved-site RT,defines the clinical target volume. For indolent NHL,often treated with RT alone,larger fields should be considered. Newer treatment techniques,including intensity modulated RT,breath holding,image guided RT,and 4-dimensional imaging,should be implemented,and their use is expected to decrease significantly the risk for normal tissue damage while still achieving the primary goal of local tumor control.

Objective This study aimed to evaluate the prognostic value of regional lymph node spread in patients with stage Ⅱ nasal-type NK/T-cell lymphoma of the upper aerodigestive tract (UADT-NKTCL).Methods From 1987 to 2013,a total of 97 patients with newly-diagnosed stage Ⅱ UADT-NKTCL were retrospectively reviewed.Primary tumors were located in the nasal cavity (n=52) or extranasal UADT sites (n=45).The majority of patients were treated with primary radiotherapy.Sixty-five patients were treated with combined modality therapy (CMT),and 32 patients were treated with radiotherapy alone (n=27) or chemotherapy alone (n=5).The Kaplan-Meier method was used to calculate the survival rate,and the log-rank test was used for survival difference analysis and monovariate prognostic analysis.The Cox regression model was used to multivariate prognostic analysis.Results The 5-year overall survival (OS) and progression-free survival (PFS) rates for all stage Ⅱ patients were 57% and 49%,respectively.The presence of a lower neck lymph node (defined as extension below the caudal border of the cricoid cartilage) was significantly associated with poor outcomes on univariate analysis and maintained significance on multivariate analysis.The median survival for patients with lower neck lymph node was 19.3 months and the 2-,5-years OS rates were 28% and 11%(P=0.000).For stage Ⅱ patients,CMT significantly improved survival.The 5-year OS and PFS rates were 64% and 52% for CMT,compared with 40.4%(P=0.006) and 42% for single modality therapy (P=0.088).Conclusion The level of regional lymph node is a powerful prognostic factor for stage Ⅱ UADT-NKTCL.The involvement of low neck lymph node is significantly associated with poorer survival outcomes.