Ankush Jajodia1, Deepa Aggarwal2, Arvind K Chaturvedi2, Avinash Rao2, Vivek Mahawar2, Munish Gairola3, Mudit Agarwal4, Sumit Goyal5, Venkata Pradeep Babu Koyyala5, Sunil Pasricha6, Rupal Tripathi7. 1. Department of Radiology, Rajiv Gandhi Cancer Hospital and Research Institute, Sector 5, Rohini 110085, Delhi, India. Electronic address: ankushjaj@gmail.com. 2. Department of Radiology, Rajiv Gandhi Cancer Hospital and Research Institute, Sector 5, Rohini 110085, Delhi, India. 3. Department of Radiation Oncology, Rajiv Gandhi Cancer Hospital and Research Institute, Sector 5, Rohini 110085, Delhi, India. 4. Department of Surgical Head & Neck Oncology, Rajiv Gandhi Cancer Hospital and Research Institute, Sector 5, Rohini 110085, Delhi, India. 5. Department of Medical Oncology, Rajiv Gandhi Cancer Hospital and Research Institute, Sector 5, Rohini 110085, Delhi, India. 6. Department of Histopathology, Rajiv Gandhi Cancer Hospital and Research Institute, Sector 5, Rohini 110085, Delhi, India. 7. Department of Research, Rajiv Gandhi Cancer Hospital and Research Institute, Sector 5, Rohini 110085, Delhi, India.
Abstract
PURPOSE: Role of diffusion-weighted (DW) MR imaging in differentiating residual or recurrent neck malignancies from postoperative/post-radiation changes with histopathological correlation and comparison with PET-CT. METHODS AND MATERIALS: Prospective observational study for a period of 1 year in 62 post-radiation/post-operative patients suspected to have residual/recurrent tumors of neck with lesion diameter more than 5 mm measured on MRI. RESULTS: Mean ADC for recurrent/residual tumors: 1.008 ± 0.220 × 10-3 mm2/s - significantly lower than mean ADC value for post-treatment changes of 1.69 ± 0.40 × 10-3 mm2/s (p < 0.0001). The overall diagnostic accuracy, positive predictive value (PPV) and negative predictive value (NPV) of the qualitative assessment for the use of DWI in differentiating tumors recurrence from post-treatment changes were 96.6%, 96% and 83.3%, respectively. Upon quantitative analysis of the DW imaging data, a threshold ADC value of 1.3 × 10-3 mm2/s used for differentiating between post-treatment changes and recurrent cancers showed the highest combined sensitivity of 94%, specificity of 83.3%, accuracy of 93.6%, positive predictive value of 95.9%, and negative predictive value of 83.3%. CONCLUSION: DW MRI is a promising non-invasive MRI technique used to differentiate recurrent/residual head and neck malignancies from posttreatment changes based on ADC values. DWI offers advantage as it has a short scanning time and can be safely added to standard MRI protocol with minimum patient discomfort. Complementary use of DWI and PET/CT imaging may increase diagnostic confidence for differentiating recurrent disease from radiation therapy-induced changes after 6-12 months in posttreatment cases.
PURPOSE: Role of diffusion-weighted (DW) MR imaging in differentiating residual or recurrent neck malignancies from postoperative/post-radiation changes with histopathological correlation and comparison with PET-CT. METHODS AND MATERIALS: Prospective observational study for a period of 1 year in 62 post-radiation/post-operative patients suspected to have residual/recurrent tumors of neck with lesion diameter more than 5 mm measured on MRI. RESULTS: Mean ADC for recurrent/residual tumors: 1.008 ± 0.220 × 10-3 mm2/s - significantly lower than mean ADC value for post-treatment changes of 1.69 ± 0.40 × 10-3 mm2/s (p < 0.0001). The overall diagnostic accuracy, positive predictive value (PPV) and negative predictive value (NPV) of the qualitative assessment for the use of DWI in differentiating tumors recurrence from post-treatment changes were 96.6%, 96% and 83.3%, respectively. Upon quantitative analysis of the DW imaging data, a threshold ADC value of 1.3 × 10-3 mm2/s used for differentiating between post-treatment changes and recurrent cancers showed the highest combined sensitivity of 94%, specificity of 83.3%, accuracy of 93.6%, positive predictive value of 95.9%, and negative predictive value of 83.3%. CONCLUSION: DW MRI is a promising non-invasive MRI technique used to differentiate recurrent/residual head and neck malignancies from posttreatment changes based on ADC values. DWI offers advantage as it has a short scanning time and can be safely added to standard MRI protocol with minimum patient discomfort. Complementary use of DWI and PET/CT imaging may increase diagnostic confidence for differentiating recurrent disease from radiation therapy-induced changes after 6-12 months in posttreatment cases.
Authors: J Y Yu; D Zhang; X L Huang; J Ma; C Yang; X J Li; H Xiong; B Zhou; R K Liao; Z Y Tang Journal: J Med Syst Date: 2020-02-26 Impact factor: 4.460