Radio(chemo)therapy in the management of squamous cell carcinoma of cervical lymph nodes from an unknown primary site. A retrospective analysis

The goal was to retrospectively review the outcome of patients with cervical lymph node metastases of squamuos cell carcinoma of unknown primary site (CUP) treated with radio(chemo)therapy. Patients and methods A total of 65 patients with CUP N1-3, M0, treated between 1988 and 2009 were evaluated: 61 patients underwent surgical resection followed by postoperative radio(chemo)therapy, 4 patients received definitive radiochemotherapy. Radiotherapy of bilateral neck nodes + the parapharyngeal region (COMP-RT) was performed in 48 patients (80%) and a unilateral radiotherapy of lymph nodes (UL-RT) in 17 patients (20%). Results After a median follow-up time of 64 months (range 3-219 months), the estimated 2- and 5-year overall survival (OS) rates were 71 ± 6% and 48 ± 7%, respectively. The recurrent free survival (RFS) rate at 2- and 5-years was 58 ± 6% and 48% ± 7%, respectively. Extracapsular spread, resection status (R0 vs. R1/R2), neck lymph node level (I-III vs. IV-V), and Karnofsky index (60-70 vs. 80-100) were significant prognostic factors for OS and RFS in the univariate analysis. Lower nodal stage (N1/N2a vs. N2b/N2c/N3) was significantly associated with a better OS. Resection status and involvement of lymph node level IV significantly affected the OS and RFS in the multivariate analysis. COMP-RT or concurrent chemotherapy was not associated with a better OS or RFS. Conclusion An advantage of comprehensive radiotherapy or radiochemotherapy compared with unilateral radiotherapy of lymph nodes was not observed. (orig.)