Chromosome stability in tonsillar squamous cell carcinoma is associated with HPV16 integration and indicates a favorable prognosis.

Tonsillar squamous cell carcinoma (TSCC) is frequently associated with human papillomavirus (HPV) and chromosome instability. Data from cellular model systems are, however, controversial concerning a relation between HPV and chromosome instability development. Here we studied this association in 77 primary TSCC with known clinical outcome and cell cycle protein expression profiles. Thirty-two tumors (42%) showed HPV16-integration. All 77 cases were analyzed by fluorescence in situ hybridization using chromosome 1- and 7-specific centromere DNA probes to detect chromosome instability, indicated by the presence of chromosome imbalances and/or polyploidization for these chromosomes. In addition, eight HPV-positive dysplasias, seven of which were adjacent to a carcinoma, were analyzed. Disomy for chromosome 1 and 7 was present in 29 out of 77 TSCC (38%), of which 19 were HPV16-positive (p = 0.002). Aneusomy was observed in the remaining 48 TSCC, of which 13 were HPV-positive. Aneusomies correlated significantly with tobacco- and alcohol consumption (p = 0.001 and p = 0.016, respectively) and a higher T-stage (p = 0.018). Both HPV-positivity and chromosome disomy were significantly associated with a favorable disease-free survival (p = 0.001 and p = 0.025, respectively). Particularly in the HPV16-positive group chromosome instability is a very strong indicator for an unfavorable prognosis (p = 0.032). In the dysplasias an identical HPV and chromosome copy number status was identified as in the adjacent tumors. We conclude that HPV-positive TSCC and their precursor lesions are more often genetically stable than HPV-negative lesions and that these tumors are associated with a favorable prognosis. Chromosome instability is an indicator for unfavorable prognosis, particularly in the HPV-positive patient group.

Diagnostic work-up and outcome of cervical metastases from an unknown primary.

CONCLUSIONS: An intensive diagnostic work-up including (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) detects many unknown primary tumours, leads to a low emergence rate of primary tumours, and selects carcinoma of unknown primary with much more favourable results after neck dissection and postoperative radiotherapy. OBJECTIVE: To investigate the optimal diagnostic approach and best treatment modality for rare head and neck cancer of unknown primary. PATIENTS AND METHODS: In a retrospective study, 69 patients admitted from 1987 to 2002 with cervical lymph node metastases without apparent primary were reviewed. Test characteristics of all diagnostic procedures were calculated. Disease-free and overall survival rates were calculated. Major prognostic factors were analysed uni-variously. RESULTS: At the primary site FDG-PET showed the best sensitivity with 69% and the highest negative predictive value with 87%. Computed tomography and magnetic resonance imaging had a better specificity with 87% and 95%, respectively. The primary tumour was detected in 23 cases (33%). Frequent primary tumour origin was the palatine tonsil (n=8, 35%), base of the tongue (n=6, 26%) and lung (n=4, 17%). All patients with unknown primary were treated by neck dissection. Adjuvant radiotherapy was performed in 26 patients (57%), concurrent radiochemotherapy was performed in 12 patients (26%). The primary emergence rate was 7%. The 5-year overall survival rate was inferior in patients with detected primary in comparison with patients with unknown primary (22% versus 52%). Significant prognostic factors in case of unknown primary were M stage, smoking, alcohol consumption and tonsillectomy. Radiotherapy but not chemotherapy with carboplatin influenced the overall survival.