Incidental Findings on FDG PET/CT in Head and Neck Cancer

Abstract

Objective 18F-fluoro-deoxy-glucose positron emission tomography/computed tomography (FDG PET/CT) imaging is common in head and neck cancer and often identifies incidental findings that necessitate additional patient evaluations. Our goal was to assess the frequency and nature of these incidental imaging findings on FDG-PET/CT. Study Design Retrospective cohort study. Setting Tertiary medical center. Subjects and Methods All patients with head and neck cancer who had undergone FDG-PET/CT imaging between January 2014 and June 2015 at our institution were evaluated for incidental findings. Results A total of 293 patients met criteria; more than one-third (n = 103) had at least 1 finding unrelated to their head and neck cancer, for a total of 134 incidental findings. Incidental findings within the head and neck (33.5% of all) excluding the thyroid were most common: 35% incidental findings were concerning for malignancy; of these, 25.5% were malignant with further workup. Recommendations were given by the head and neck radiologist on 72 (53.7%) findings: 74.5% of potentially malignant findings and 42.5% of benign findings had recommendations for follow-up. Significantly more patients with findings described as malignant were given recommendations for follow-up ( P = .0004). Conclusion Incidental findings on FDG-PET/CT are present in more than one-third of patients with head and neck cancer. More than one-third of incidental findings were concerning for malignancy. This study illustrates how the incidental findings discovered on FDG PET/CT frequently necessitate additional evaluations unrelated to the index head and neck cancer. The impact of these additional assessments on the cost and quality of health care warrants future evaluation.

Incidental findings on 18-FDG PET–CT in head and neck cancer. A retrospective case-control study of incidental findings on 18-FDG PET–CT in patients with head and neck cancer

“…The authors were able to find one other study investigating the same topic specifically in head and neck cancers. This was undertaken in the USA, where Britt et al report rates of 14.6% suspected malignancy, with 4.1% (12/293) confirmed new unrelated malignancy (5 were thyroid cancer; 2, lung cancer; 2, gastrointestinal; and 1 each of HNC, lymphoma, and genitourinary cancer) [ 7 ], a rate which is similar to our UK cohort.…”

Benefits And Harms Of Implementing [18F]FDG-PET/CT For Diagnosing Recurrent Breast Cancer: A Prospective Clinical Study

“…This number corresponds well with the 3.88% of incidental ndings in a population of high-risk primary breast cancer in the same institution and time [10]. Other studies on different cancers have also found between 1-8% of additional malignancies at [ 18 F]FDG-PET/CT [9,[15][16][17][18].…”

Impact of pretreatment second look 18FDG-PET/CT on stage and treatment changes in head and neck cancer

“…Additionally, MRI is substantially hampered by dental artifacts, which is quite relevant for the visualization of the oral cavity and some oropharyngeal tumors. Moreover, according to our experience, dedicated highresolution PET/CT of the head and neck region appears at least noninferior or even superior to MRI and CT for the detection of pathologically involved lymph nodes and distant metastases and helps to detect second primary malignancies [9,10,19,[11][12][13][14][15][16][17][18]. On the other hand, the anatomical resolution, tissue contrast and availability of different functional imaging sequences make MRI the superior modality for the identification and demarcation of primary tumors [20].…”