Carcinoma of Unknown Primary (CUP) versus CUP Turned to Primary Carcinoma of the Head and Neck-An Analysis of Diagnostic Methods and the Impact of Primary Tumor on Clinical Outcome.

BACKGROUND: The purpose of this study was to analyze the value of different diagnostic methods in detecting the primary site and the impact of primary tumors on the clinical outcome of carcinoma of unknown primary (CUP). METHODS: In this multicenter, retrospective study, 124 patients with true CUP (n = 94) and CUP turned to primary carcinoma (n = 30) were included. Patients with evidence of primary site during the clinical examination were excluded a priori. The diagnostic procedure was comprised of imaging and invasive methods (fine-needle-aspiration, tonsillectomy and panendoscopy). All patients were treated with curative intent. RESULTS: Despite extensive diagnostic workup, the primary site remained unknown in 75.8%. Invasive diagnostic methods showed higher primary detection rates than imaging modalities (15.1% vs. 7.8%). Tonsillectomy and panendoscopy revealed the primary tumor in 14.9% and 15.2% of patients, whereas the detection rates of CT, MRI and FDG-PET-CT were 10.1%, 4.8% and 6.5%, respectively. The occurrence of primary tumors led to a significantly deteriorating 5-year overall survival (p = 0.002) and emerged as survival prognosticator (HR = 2.764, p = 0.003). CONCLUSION: Clinical examination in combination with tonsillectomy and panendoscopy was superior to imaging alone in detecting the primary tumor. When the CUP of patients turned to a primary tumor, clinical outcome was significantly worse than in CUP patients.

Bilateral vs ipsilateral adjuvant radiotherapy in patients with cancer of unknown primary of the head and neck: An analysis of the clinical outcome and radiation-induced side effects.

BACKGROUND: The purpose of this study was to analyze and compare ipsilateral and bilateral adjuvant radiotherapy in patients with cancer of unknown primary (CUP) of the head and neck. METHODS: Overall survival, recurrence-free survival, and radiation-induced side effects were assessed in 76 patients with CUP who underwent ipsilateral (n = 29) or bilateral (n = 47) radiotherapy. RESULTS: At a median follow-up of 41 months, the 5-year overall survival and recurrence-free rate were 67.9% and 71.5%, respectively. No statistically significant difference between ipsilateral and bilateral radiotherapy could be found regarding 5-year overall survival, recurrence-free survival, occurrence of a primary tumor, and distant metastasis. The analysis of radiation-induced acute side effects showed a significant benefit of ipsilateral radiotherapy. CONCLUSION: As the main parameters of the study regarding the outcome and radiation-induced side effects showed no advantages of bilateral radiotherapy, the strategy of ipsilateral radiotherapy can be recommended for the adjuvant treatment of CUP patients.