Patterns of spread of distant metastases in head and neck cancer.

Adult Aged Autopsy Bone Neoplasms Carcinoma, Squamous Cell/radiotherapy,surgery Female Gastrointestinal Neoplasms Head and Neck Neoplasms/mortality,radiotherapy,surgery Heart Neoplasms Humans Liver Neoplasms Lung Neoplasms Lymphatic Metastasis Male Middle Aged Mouth Neoplasms/mortality,radiotherapy,surgery Nasopharyngeal Neoplasms Neoplasm Metastasis Neoplasms, Multiple Primary Radiotherapy Dosage Splenic Neoplasms