We investigated the prognostic role of metabolic parameters from preoperative ¹⁸F-FDG PET/CT in stage II/III colorectal adenocarcinoma. A total of 327 stage II/III colorectal adenocarcinoma patients who underwent curative resection were included. The maximal standard uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were analyzed for optimal cut-offs and their effect on DFS. Differences in DFS rates and hazard ratios for DFS between cut-offs were statistically significant in SUVmax, MTV2.5, MTV3, TLG 2.5, TLG3, and TLG30%. Factors significantly related to DFS in univariate Cox regression were age, sex, stage, preoperative CEA, SUVmax, MTV2.5, MTV3, TLG2.5, TLG3, and TLG30%. Age, sex, preoperative CEA, and TLG2.5 (p = 0.009) sustained statistically significant difference in multivariate analysis. The 1-, 3-, and 5-year DFS rates for TLG2.5 ≤ 448.5 were 98.1%, 79.6%, and 74.8%, significantly higher than 78.4%, 68.5%, and 61.1% of TLG2.5 > 448.5, respectively (p = 0.012). TLG, a parameter indicating both the metabolic activity and metabolic volume, was the strongest predictor independently associated with DFS, among several PET parameters with statistical significance. These results suggest the potential prognostic value of preoperative ¹⁸F-FDG PET/CT in stage II/III resectable colorectal cancer.

Herpes zoster is a reactivated varicella-zoster virus infection and demonstrates typical dermatomal distribution. We herein describe a case of a 41-year-old woman with a history of ovarian cancer. Intense hot uptake in the left breast and enlarged ipsilateral axillary lymph nodes were noted on ¹⁸F-FDG PET/CT for adjuvant chemotherapy response evaluation. Blinded to the patient's clinical information, these lesions were interpreted as incidental breast cancer with axillary nodal metastasis. However, clinically she presented with vesicles along the T4 dermatome and palpable enlarged nodes in the left axilla. On 3-month follow-up PET/CT after antiviral treatment, these intense hot uptake areas were no longer visualized.