Squamous Cell Carcinoma of the Head and Neck: Comparison of Diffusion-weighted MRI at b-values of 1,000 and 2,000 s/mm² to Predict Response to Induction Chemotherapy

Abstract

Purpose: Recent publications have reported contradictory results of pretreatment diffusion-weighted magnetic resonance imaging (DWI) for the prediction of chemoradiotherapeutic response in primary squamous cell carcinomas of the head and neck (HNSCC). Therefore, we evaluated the diagnostic performance of DWI obtained with both standard (b = 0 and 1,000 s/mm 2 ) and high (b = 0 and 2,000 s/mm 2 ) b-values for predicting response to induction chemotherapy in HNSCCs.Methods: For 25 patients with primary HNSCC who underwent DWI with both standard and high b-values prior to treatment, we calculated corresponding apparent diffusion coefficient (ADC) maps. Regions of interest containing the tumor were drawn on every section of ADC maps and summated to make volume-based data of the entire tumor. Histogram parameters (mean ADC, kurtosis, and skewness) were correlated with treatment response using unpaired Student t test. Univariate and multivariate analysis of the ADC parameters, patient age, sex, whole tumor volume, and T stage were also performed to predict tumor response to induction chemotherapy.Results: Response to induction chemotherapy was good in 13 of the 25 patients and poor in 12. The mean ADC values of good responders at standard b-value (ADC 1000 ), 1.23 « 0.34 (© 10 ¹3 mm 2 /s), and high b-value (ADC 2000 ), 0.62 « 0.14 (© 10 ¹3 mm 2 /s), were lower than those of poor responders (ADC 1000 , 1.32 « 0.28 [© 10 ¹3 mm 2 /s]; ADC 2000 , 0.76 « 0.15 [© 10 ¹3 mm 2 /s]), but significant difference was achieved only at the ADC 2000 map (P = 0.02). In addition, mean tumor volume prior to treatment of good responders was smaller than that of poor responders. However, at multiple logistic regression analysis, only the mean ADC 2000 value remained as a significant predictor of response to induction chemotherapy.Conclusion: DWI with high b-values (b = 0 and 2,000 s/mm 2 ) as an assessment of ADC values may help predict tumor response to neoadjuvant chemotherapy for primary HNSCCs.

Intravoxel incoherent motion and ADC measurements for differentiating benign from malignant thyroid nodules: utilizing the most repeatable region of interest delineation at 3.0 T

“…The results showed that the ADC values were higher than the D values, which may be related to the mix-up of perfusion factors in the biexponential model. This finding is consistent with those of other studies on the head and neck [8,38]. IVIM was used to identify the effects of diffusion and perfusion (pseudo-diffusion).…”

Post-treatment benign changes versus recurrence in non-lymphoid head and neck malignancies: can diffusion-weighted magnetic resonance imaging end up the diagnostic challenge?

“…Several authors have also investigated the advantages of using high b values (e.g. b2000) in the assessment of post-treatment head and neck lesions [19][20][21][22].…”

Diffusion-Weighted Mri and Proton Magnetic Resonance Spectroscopy in the Diagnosis and Evaluation of the Effectiveness of Chemoradiotherapy of Head and Neck Tumors (The Literature Review)

“…В последнее время в диагностике опухолей головы и шеи применяют ДВ МРТ с более высокими диапазонами значений b-фактора, до b = 1500/2000 [10]. Это объясняется тем, что подобные высокие значения b-фактора способны оценить медленную внутриклеточную диффузию молекул воды, связанную со сложными структурами и клеточными оболочками [12][13][14][15][16]. Большинство видов рака демонстрирует большее ограничение диффузии молекул воды, чем здоровые ткани и доброкачественные процессы, что в свою очередь приводит к более высокой визуальной интенсивности сигнала на томограммах с высоким b-фактором (~b = 800/1000) и более низкой интенсивности сигнала на ИКД-картах, измеряемых в мм 2 /сек (рис.…”