The Blood Oxygenation T 2 * Values of Resectable Esophageal Squamous Cell Carcinomas as Measured by 3T Magnetic Resonance Imaging: Association with Tumor Stage.

Objective: To explore the association between the blood oxygenation T ₂ ^* values of resectable esophageal squamous cell carcinomas (ESCCs) and tumor stages.
Materials and Methods: This study included 48 ESCC patients and 20 healthy participants who had undergone esophageal T ₂ ^* -weighted imaging to obtain T ₂ ^* values of the tumors and normal esophagi. ESCC patients underwent surgical resections less than one week after imaging. Statistical analyses were performed to identify the association between T ₂ ^* values of ESCCs and tumor stages.
Results: One-way ANOVA and Student-Newman-Keuls tests revealed that the T ₂ ^* value could differentiate stage T1 ESCCs (17.7 ± 3.3 ms) from stage T2 and T3 tumors (24.6 ± 2.7 ms and 27.8 ± 5.6 ms, respectively; all p _s < 0.001). Receiver operating curve (ROC) analysis showed the suitable cutoff T ₂ ^* value of 21.3 ms for either differentiation. The former statistical tests demonstrated that the T ₂ ^* value could not differentiate between stages T2 and T3 (24.6 ± 2.7 ms vs. 27.8 ± 5.6 ms, respectively, p > 0.05) or between N stages (N1 vs. N2 vs. N3: 24.7 ± 6.9 ms vs. 25.4 ± 4.5 ms vs. 26.8 ± 3.9 ms, respectively; all p _s > 0.05). The former tests illustrated that the T ₂ ^* value could differentiate anatomic stages I and II (18.8 ± 4.8 ms and 26.9 ± 5.9 ms, respectively) or stages I and III (27.3 ± 3.6 ms). ROC analysis depicted the same cutoff T ₂ ^* value of 21.3 ms for either differentiation. In addition, the Student's t test revealed that the T ₂ ^* value could determine grouped T stages (T0 vs. T1-3: 17.0 ± 2.9 ms vs. 25.2 ± 6.2 ms; T0-1 vs. T2-3: 17.3 ± 3.0 ms vs. 27.1 ± 5.3 ms; and T0-2 vs. T3: 18.8 ± 4.2 ms vs. 27.8 ± 5.6 ms, all p _s < 0.001). ROC analysis indicated that the T ₂ ^* value could detect ESCCs (cutoff, 20 ms), and discriminate between stages T0-1 and T2-3 (cutoff, 21.3 ms) and between T0-2 and T3 (cutoff, 20.4 ms).
Conclusion: The T ₂ ^* value can be an additional quantitative indicator for detecting ESCC except for stage T1 cancer, and can preoperatively discriminate between some T stages and between anatomic stages of this tumor.