RESUMO
BACKGROUND: Primary radio(chemo)therapy [R(C)T] is a treatment option for advanced oropharyngeal squamous cell carcinoma (OSCC). Nevertheless, early diagnostics of treatment failure is problematic. Cytokeratin fragment 19 (CYFRA 21-1), an established marker in the management of pulmonary cancer, might be helpful here. Hence, in this study the impact of CYFRA 21-1 as an indicator for treatment failure and tumor recurrence (TR) in OSCC after R(C)T was analyzed. PATIENTS AND METHODS: The data of 77 patients with advanced OSCC and R(C)T were retrospectively examined. For determination of CYFRA 21-1 at the time of diagnosis and after R(C)T, an electrochemiluminescence immunoassay was used. Tumor residuals and tumor recurrence were pathologically verified after detection by radiological imaging and endoscopy. The mean follow-up was 44.4 months. RESULTS: After R(C)T, 48 (62%) patients showed locoregional control and 29 (38%) patients experienced locoregional failure. No statistical difference in the CYFRA 21-1 level between groups both before (p=0.75) and after R(C)T (p=0.85) was found. Nevertheless, in cases of TR in follow-up, the CYFRA 21-1 level was significantly higher (p≤0.01). The occurrence of TR was significantly associated with a CYFRA 21-1 elevation at this time (p≤0.01). However, CYFRA 21-1 failed to show a suitable discriminative ability for TR (area under the curve=0.57). CONCLUSION: In OSCC, CYFRA 21-1 does not seem to be a useful marker for locoregional failure after R(C)T. Nevertheless, a higher level immediately after R(C)T and in the further course of the disease may be associated with TR in individual patients.