Nonexophytic nasopharyngeal carcinoma: high frequency of advanced lymph node and distant metastasis

Nasopharyngeal carcinoma (NPC) usually presents with an exophytic mass. However, some patients present with biopsy-proven NPC but normal-appearing nasopharynx on endoscopic examination (nonexophytic NPC). The authors aim to characterize the clinicopathological features and survival outcomes of nonexophytic NPC in a high-incidence area.

A retrospective cohort analysis of 274 patients with NPC in a tertiary institution.

On the basis of endoscopic findings, the patients were categorized into nonexophytic and exophytic NPC. Clinical, pathological, and survival outcomes between the 2 groups were compared.

Nonexophytic NPC was present in 24 patients (8.8%). A greater proportion of patients with nonexophytic NPC presented with T1 tumors compared to patients with exophytic NPC (70.8% vs 35.2%, P = .004). Similarly, a higher proportion of patients with nonexophytic NPC compared with exophytic NPC presented with both N3 and M1 disease (37.5% vs 13.2%, P = .01 and 25.0% vs 6%, P = .005, respectively). The mean duration of symptoms of patients did not differ significantly. The 5-year disease-specific and disease-free survivals did not show any significant differences.

Nonexophytic NPC appears to be associated with higher risks of both N3 and M1 disease at presentation. However, these patients have similar treatment outcomes compared to patients with exophytic NPC. Although nonexophytic NPC appears to be an aggressive variant, current treatment protocols are as effective as for the group with exophytic NPC. Awareness of the existence of nonexophytic NPC is important for adequate diagnostic workup of patients with this subset of NPC.