Purpose of the Report Without the routine use of 18 F-FDG PET for initial staging of esophageal cancer, it may lead to inaccurate staging and suboptimal treatment. The purpose of this study was to evaluate the prognostic significance of pretreatment 18 F-FDG PET in nonmetastatic esophageal cancer by comparing the survival between patients with and without pretreatment PET. Materials and Methods We selected newly diagnosed esophageal cancer patients without metastasis between 2009 and 2015 from Taiwan Cancer Registry and National Health Insurance Research Database. Pretreatment 18 F-FDG PET staging was determined according to the implementation of PET within 90 days before starting treatment. Overall survival was calculated from the day of treatment initiation to the death from any cause. Survival curves were compared between patients with and without PET staging using the log-rank test. Results Of the 9078 patients included, 1765 (19.4%) and 7313 (80.6%) patients were staged with and without pretreatment PET, respectively. The median follow-up time for all patients and survivors was 1.29 years and 5.46 years, respectively. The pretreatment PET group had a lower risk of death than the no pretreatment PET group (hazards ratio, 0.74; 95% confidence interval, 0.70–0.79; P < 0.001). After adjusting for age, stage, histology, and tumor location, pretreatment PET remained significantly correlated with a lower risk of death (hazards ratio, 0.78; 95% confidence interval, 0.73–0.83; P < 0.001). Conclusions The utilization of pretreatment 18 F-FDG PET for staging in nonmetastatic esophageal malignancy is associated with a lower risk of death even after adjusting for age, stage, histology, and tumor location.

Concurrent chemoradiotherapy is the established treatment for locally advanced nasopharyngeal carcinoma (NPC). However, there is no evidence supporting routine adjuvant chemotherapy. We aimed to demonstrate the effect of adjuvant chemotherapy on survival and distant metastasis in high-risk N3 NPC patients. We linked the Taiwan Cancer Registry and Cause of Death database to obtain data. Clinical N3 NPC patients were divided as those receiving definitive concurrent chemoradiotherapy (CCRT) with adjuvant 5-fluorouracil and platinum (PF) chemotherapy and those receiving no chemotherapy after CCRT. Patients receiving neoadjuvant chemotherapy were excluded. We compared overall survival, disease-free survival, local control, and distant metastasis in both groups using Cox proportional hazards regression analysis. Propensity-score matching was also performed to evaluate the independent effect of adjuvant PF in a matched cohort with similar baseline characteristics. We included 431 patients (152 and 279 patients in the adjuvant PF and observation groups, respectively). Median follow-up was 4.3 years. The 5-year overall survival were 69.1% and 57.4% in the adjuvant PF chemotherapy and observation groups, respectively (p = 0.02). Adjuvant PF chemotherapy was associated with a lower risk of death (hazard ratio [HR] 0.61, 95% confidence interval [CI] 0.43–0.84; p = 0.003), even after adjusting for baseline prognostic factors (HR 0.61, 95% CI 0.43–0.86; p = 0.005). Distant metastasis-free survival at 12 months was higher in the adjuvant PF chemotherapy group than in the observation group (98% vs 84.8%; p < 0.001). After adjusting for baseline prognostic factors, adjuvant PF chemotherapy was associated with freedom from distant metastasis (HR 0.11, 95% CI 0.02–0.46; p = 0.003). Adjuvant chemotherapy was also associated with a decreased risk of death (HR 0.59, 95% CI 0.41–0.85, p = 0.004) in a propensity score-matched cohort. Prospective evaluation of adjuvant PF chemotherapy in N3 NPC patients treated with definitive CCRT is warranted because adjuvant PF chemotherapy was associated with improved overall survival and decreased risk of distant metastasis.

Dual-time-point 18F-flluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) can be used to differentiate benign vascular tumors from other malignant growths. We present the case of a 70-year-old woman with a history of cervical carcinoma who was referred for PET/CT to examine a left chest wall tumor noted on CT, which involved the adjacent rib and pleura, thus raising the suspicion of metastasis. The chest wall tumor demonstrated moderate FDG uptake and further decreased uptake at the delayed-phase scanning, corresponding to biodistribution of FDG in the blood pool. These findings indicated a benign hemangioma rather than a metastasis.

Background Radiation-induced hypothyroidism (RIHT) is a common, but underestimated, late adverse effect in head and neck cancer. We investigated the value of early post-treatment 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) for predicting RIHT. Methods We searched our institutional database for patients aged ≥ 20 years who had undergone definitive radiotherapy for nasopharyngeal or oropharyngeal cancer between 2005 and 2017, followed by 18F-FDG PET/CT within 180 days of radiotherapy completion. We visually assessed and compared PET/CT and baseline characteristics in patients with and without RIHT using the chi-square test for categorical variables and the t-test for continuous variables. Variable predictive ability was evaluated by measuring the area under receiver operating characteristic curves. Results Fifty-two patients were included; 22 (42%) developed RIHT and 30 (58%) did not. Two patients presented with diffuse thyroid uptake on PET/CT via visual assessment, and both developed RIHT later. Among the PET/CT variables, thyroid functioning volume was significantly higher in patients without RIHT than in patients with RIHT (16.30 ± 6.03 cm3 vs. 10.61 ± 3.81 cm3, p < 0.001). The maximum standard uptake values of the thyroid and pituitary glands did not differ significantly between the groups. Two patient characteristics, pretreatment thyroid volume and mean radiotherapy dose to the thyroid, also showed significant differences between the groups. An algorithmic approach combining visual grading of thyroid 18F-FDG uptake and thyroid functioning volume cutoff of 14.01 yielded an area under curve of 0.89 (95% confidence interval, 0.80–0.98); the sensitivity, specificity, positive predictive value, and negative predictive value were 87.0%, 82.3%, 80.0%, and 88.9%, respectively. Conclusion Early post-treatment PET/CT-derived thyroid functioning volume was a good predictor of RIHT development. Diffusely increased thyroid 18F-FDG uptake on PET/CT may indicate impending RIHT. Routine surveillance of thyroid function is warranted in patients at high risk of developing RIHT.