Volumetric MR imaging of oral, maxillary sinus, oropharyngeal, and hypopharyngeal cancers: correlation between tumor volume and lymph node metastasis.

BACKGROUND AND PURPOSE The size of the primary lesion and the lymph node metastasis are critical indicators for the patient prognosis. Here we attempted to assess the correlation between these 2 prognostic parameters in patients with oropharyngeal, hypopharyngeal, oral, or maxillary sinus cancer. METHODS We retrospectively studied 66 patients with oropharyngeal or hypopharyngeal (n = 24), oral (n = 35), or maxillary sinus (n = 7) cancer. Of these patients, 25 (10 with oral or maxillary sinus and 15 with pharyngeal cancers) had lymph node metastases. We measured the volumes of the primary lesions as sums of gadolinium-enhanced areas on fat-suppressed, spectral presaturation with inversion recovery (SPIR) T1-weighted images. Histologically confirmed metastatic nodes were mapped to the neck levels. RESULTS The tumor volumes were well correlated with the clinical T-category for the primary lesions in oral, maxillary sinus, and oropharyngeal and hypopharyngeal cancers. The volumes of the oropharyngeal and hypopharyngeal cancers were significantly greater (P < .05) in patients with metastatic nodes than in patients without metastasis, whereas there was no significant correlation between the tumor volume and nodal metastasis in patients with oral or maxillary sinus cancer (Mann-Whitney U test). Furthermore, the correlation between tumor volume and the distribution of metastatic nodes in the neck was observed to be weak in patients with oral or maxillary sinus cancer. CONCLUSION The MR image-based tumor volume measurement proved to be clinically feasible. We observed a good correlation between tumor volume and lymph node metastasis in patients with oropharyngeal or hypopharyngeal cancer but not in those with oral or maxillary sinus cancer.