Locally advanced nasopharyngeal carcinoma: computed tomography findings, clinical evaluation, and treatment outcome

We present our experience with computed tomography (CT) for delineating the extent of bone erosion in nasopharyngeal carcinoma (NPC) and propose that a new subdivision of Stage T4 disease be added to the staging criteria for cases of minimal bone disease, defined as erosion of the base of the sphenoid or the pterygoid without cranial nerve (CN) involvement.

We retrospectively reviewed the clinical findings, radiological findings, and treatment outcome in 64 patients with Stage T4 NPC, diagnosed according to the American Joint Committee on Cancer 4th edition criteria. The median follow-up was 34 months (range, 3-118 months). Statistical analyses were performed using the chi-square test, the Kaplan-Meier method, and the log-rank test.

Local control was achieved in 19 (46%) of 41 patients with CN deficits and 18 (78%) of 23 patients without CN deficits (p = 0.01). Overall 5-year survival with and without CN deficits was 25% and 58%, respectively (p = 0.01). When the 16 patients with minimal bone disease were compared to the remaining 48 patients, there were significant differences in local control rates (87% vs. 48%, p = 0. 006) and 5-year survival rates (68% vs. 28%, p = 0.008).

Among patients with Stage T4 NPC, a subgroup of patients with only minimal bone disease may have a more favorable prognosis, which may have a considerable bearing on our approach to this patient group.