Unknown primary detected by FDG-PET. A review of the present indications of FDG-PET in head and neck cancers.

To investigate the indications of 18F-2-fluoro-2-Deoxy-D-glucose (FDG) Positron Emission Tomography (PET) in head and neck cancer, the present study focuses on a case of cervical metastatic lymph node, which is not detected by the routine approach. It discusses the potential role of FDG-PET in the detection of unknown primary tumors, lymph node metastasis and post radiation follow-up, and demonstrates the implications of its findings through a few examples. Based on the literature in the field of head and neck oncology, the paper recommends the following uses for FDG-PET: 1. To guide biopsy or even local resection at the initial stage of examining the unknown primary lesions in case of high clinical suspicion 2. A whole body PET in high-risk patients may prevent unnecessary treatment and reduce the number of examinations 3. To monitor tumor response before full-dose irradiation so as not to delay the salvage surgery when applicable 4. To detect residual, recurrent or secondary neoplasm after definitive radiotherapy at least 4 months post-treatment 5. To revise the necessity of neck treatment in case of a negative PET, in the NO necks; and 6. In cases of clinical suspicion for laryngeal cancer recurrence and absence of objective findings before obtaining biopsy.

The levels of expression of galectin-3, but not of galectin-1 and galectin-8, correlate with apoptosis in human cholesteatomas.

OBJECTIVES: To investigate whether galectins 1, 3, and 8 are expressed in human cholesteatomas and whether any such expression does correlate with the level of apoptosis, which is, as we have previously shown, predictive of recurrence.7 STUDY DESIGN: The analysis of 52 cholesteatomas resected by the same surgeon by means of canal wall up and canal wall down procedures. METHODS: The immunohistochemical levels of expression of galectins 1, 3, and 8 were quantitatively determined (using computer-assisted microscopy) on conventional histological slides by means of specific anti-galectin-1, anti-galectin-3, and anti-galectin-8 antibodies. The level of apoptosis in each cholesteatoma under study had already been determined 7 by means of the in situ labeling of nuclear DNA fragmentation (Tolt-mediated dUTP nick end labeling [TUNEL] staining). RESULTS: Galectin-1 was expressed markedly in both the epithelial and the connective tissue areas of all the cholesteatomas under study. The levels of expression of galectin-3 and galectin-8 were considerably lower than that of galectin-1. The level of expression of galectin-3 correlated both highly and positively with the level of apoptosis. CONCLUSIONS: An upregulation of galectin-3 (known to have an antiapoptotic and antianoikis effect in certain model systems) expression, which is associated with pronounced apoptotic activity, could have a physiologically protective effect against the characteristically substantial apoptotic features occurring in recurrent cholesteatomas.