Pathogenesis of middle-ear effusion in nasopharyngeal carcinoma: a new perspective.

The theory that middle-ear effusion (MEE) associated with nasopharyngeal carcinoma (NPC) is merely the result of tensor veli palatinus destruction is deficient because recent studies have shown that many patients with NPC have MEE but no tensor veli palatinus dysfunction. The present study evaluates the relationship between MEE and Eustachian cartilage erosion by NPC and examines the pathogenesis of NPC-associated MEE from a new perspective. Thirty-five patients with NPC were studied by magnetic resonance scans taken along the lengths of the Eustachian tubes. Twenty-four patients had tumour involvement of both sides of the nasopharynx so that 59 ears were available for study. Eighteen ears had MEE of which 12 had Eustachian cartilage erosion (p < 0.00001), Fischer's Exact Test). In ears with MEE, Eustachian cartilage erosion was frequently but not necessarily associated with tensor veli palatinus destruction. We postulate that altered Eustachian tubal compliance as a result of cartilage erosion by tumour is an important reason why middle-ear effusions develop in patients with NPC.