Efficacy of Diffusion-Weighted Imaging for the Differentiation between Lymphomas and Carcinomas of the Nasopharynx and Oropharynx: Correlations of Apparent Diffusion Coefficients and Histologic Features

Axial fat-suppressed T2-weighted images (left panels), color ADC maps (middle panels), and photomicrographs (right panels) of lymphomas and carcinomas of the nasopharynx and oropharynx. A, A 92-year-old woman with oropharyngeal lymphoma (overall ADC = 0.558 × 10⁻³ mm²/s; ADC mapping = 79%, extremely low; 21%, low; 0%, intermediate; and 0%, high). B, A 49-year-old woman with NPC (overall ADC = 0.566 × 10⁻³ mm²/s; ADC mapping = 55%, extremely low; 45%, low; 0%, intermediate; and 0%, high). C, A 52-year-old man with poorly differentiated SCC exhibiting homogeneous T2 signals (overall ADC = 0.576 × 10⁻³ mm²/s; ADC mapping = 21%, extremely low; 78%, low; 1%, intermediate; and 0%, high). D, A 66-year-old man with poorly differentiated SCC exhibiting heterogeneous T2 signals (overall ADC = 1.02 × 10⁻³ mm²/s; ADC mapping, = 4%, extremely low; 65%, low; 31%, intermediate; and 1%, high). E, A 67-year-old man with moderately differentiated SCC exhibiting homogeneous T2 signals (overall ADC = 0.752 × 10⁻³ mm²/s; ADC mapping = 22%, extremely low; 77%, low; 1%, intermediate; and 0%, high). F, A 62-year-old man with moderately differentiated SCC exhibiting heterogeneous T2 signals (overall ADC = 0.904 × 10⁻³ mm²/s; ADC mapping = 21%, extremely low; 61%, low; 15%, intermediate; and 3%, high). G, A 66-year-old man with well-differentiated SCC (overall ADC = 0.975 × 10⁻³ mm²/s; ADC mapping = 5%, extremely low; 83%, low; 12%, intermediate; and 1%, high). The color scale for ADC mapping is shown at the bottom. White curvilinear lines indicate ROIs. Bars in photomicrographs (H&E) are scale bars (50 μm).