CASE PRESENTATION: The featured case describes a 40-year-old male who presented with symptoms suggestive for sinusitis. Further diagnostic investigation by the functional endoscopic sinus surgery (FESS) revealed a chronic sinusitis with multiple biopsies showing negative for malignancy, viral and bacterial infections and therefore undiagnosed for sinonasal NK/T-cell lymphoma. Subsequently after a month of surgery, he developed multiple lymph nodes in inguinal where biopsy revealed extranodal NK/T-cell non-Hodgkin lymphoma, high grade but in no time for treatment, he finally succumbed to the illness.
CONCLUSION: The case presented here was initially diagnosed as a chronic sinusitis, not as sinonasal NK/Tcell lymphoma which later developed into extranodal NK/T-cell lymphoma. The prognosis showed improvement for nasal lymphomas but remains poor for disseminated and extranasal lymphomas which are more aggressive with lower survival rate. It is clinically important to differentiate diseases for proper staging and monitoring as they require completely different treatment strategies.
METHODS: We did a retrospective study of patients with newly diagnosed ENKTL without any previous treatment history for the disease who were given non-anthracycline-based chemotherapies with or without upfront concurrent chemoradiotherapy or radiotherapy with curative intent. A prognostic model to predict overall survival and progression-free survival on the basis of pretreatment clinical and laboratory characteristics was developed by filling a multivariable model on the basis of the dataset with complete data for the selected risk factors for an unbiased prediction model. The final model was applied to the patients who had complete data for the selected risk factors. We did a validation analysis of the prognostic model in an independent cohort.
FINDINGS: We did multivariate analyses of 527 patients who were included from 38 hospitals in 11 countries in the training cohort. Analyses showed that age greater than 60 years, stage III or IV disease, distant lymph-node involvement, and non-nasal type disease were significantly associated with overall survival and progression-free survival. We used these data as the basis for the prognostic index of natural killer lymphoma (PINK), in which patients are stratified into low-risk (no risk factors), intermediate-risk (one risk factor), or high-risk (two or more risk factors) groups, which were associated with 3-year overall survival of 81% (95% CI 75-86), 62% (55-70), and 25% (20-34), respectively. In the 328 patients with data for Epstein-Barr virus DNA, a detectable viral DNA titre was an independent prognostic factor for overall survival. When these data were added to PINK as the basis for another prognostic index (PINK-E)-which had similar low-risk (zero or one risk factor), intermediate-risk (two risk factors), and high-risk (three or more risk factors) categories-significant associations with overall survival were noted (81% [95% CI 75-87%], 55% (44-66), and 28% (18-40%), respectively). These results were validated and confirmed in an independent cohort, although the PINK-E model was only significantly associated with the high-risk group compared with the low-risk group.
INTERPRETATION: PINK and PINK-E are new prognostic models that can be used to develop risk-adapted treatment approaches for patients with ENKTL being treated in the contemporary era of non-anthracycline-based therapy.
FUNDING: Samsung Biomedical Research Institute.