Wakana Murakami1, Mitsuhiro Tozaki2, Michiro Sasaki3, Akira I Hida4, Yasuyo Ohi5, Kazunori Kubota6, Yoshiaki Sagara7. 1. Department of Radiology, National Defense Medical College, 3-2 Namiki, Tokorozawa City, Saitama, Japan. Electronic address: wkn.murakami@gmail.com. 2. Department of Radiology, Sagara Hospital, 3-31 Matsubara-cho, Kagoshima City, Kagoshima, Japan. 3. Department of Radiology, Sagara Perth Avenue Clinic, 26-13 Shinyashiki-cho, Kagoshima City, Kagoshima, Japan. 4. Department of Pathology, Matsuyama Shimin Hospital, 2-6-5 Otemachi, Matsuyama, Ehime, Japan. 5. Department of Pathology, Sagara Hospital, 3-31 Mtsubara-cho, Kagoshima City, Kagoshima, Japan. 6. Department of Radiology, Dokkyo Medical University School of Medicine, 880 Kita-kobayashi, Mibumachi, Shimotsuga-gun, Tochigi, Japan. 7. Department of Radiology, Sagara Hospital Affiliated Breast Center, 3-28 Tenokuchi-cho, Kagoshima City, Kagoshima, Japan.
Abstract
PURPOSE: The tumor microenvironment is related to the metabolism of cancer cells and local immune reactions. Previous studies have established TILs could be a significant prognostic factor, especially for triple-negative breast cancers (TNBC) and human epithelial growth factor receptor 2 (HER2)-positive breast cancers. We explore the association between metabolic information on PET/MRI with TILs in TNBC and HER2-positive breast cancer. METHOD: We retrospectively reviewed the cases of 55 women with triple-negative or HER2-positive invasive ductal carcinomas who had undergone 18F-FDG PET/MRI without neo-adjuvant treatment for pre-operative evaluation. FDG uptake was quantified as standardized uptake value (SUV) max. The existence of peritumoral edema on PET/MRI was also recorded. The TIL score of the breast cancers was defined histologically on the basis of the proportion of the area infiltrated by lymphocytes, and classified as low (<10 %), intermediate (10-50 %), and high (>50 %). The association between PET/MRI findings and TILs was assessed using Kruskal-Wallis test and Wilcoxon signed-rank test. RESULTS: There were 14 high TIL, 20 intermediate TIL and 21 low TIL lesions. Higher values of SUVmax were found in the high and intermediate TIL group as compared to the low TIL group (P = 0.013). On the other hand, the lesions with peritumoral edema in the low TIL group tended to show high SUVmax (P = 0.014). CONCLUSIONS: 18F-FDG uptake on PET/MRI correlated with TIL levels in patients with TNBC and HER2-positive breast cancer. This finding suggests that preoperative PET/MRI may be useful as a non-invasive tool for guiding the treatment plan.
PURPOSE: The tumor microenvironment is related to the metabolism of cancer cells and local immune reactions. Previous studies have established TILs could be a significant prognostic factor, especially for triple-negative breast cancers (TNBC) and human epithelial growth factor receptor 2 (HER2)-positive breast cancers. We explore the association between metabolic information on PET/MRI with TILs in TNBC and HER2-positive breast cancer. METHOD: We retrospectively reviewed the cases of 55 women with triple-negative or HER2-positive invasive ductal carcinomas who had undergone 18F-FDG PET/MRI without neo-adjuvant treatment for pre-operative evaluation. FDG uptake was quantified as standardized uptake value (SUV) max. The existence of peritumoral edema on PET/MRI was also recorded. The TIL score of the breast cancers was defined histologically on the basis of the proportion of the area infiltrated by lymphocytes, and classified as low (<10 %), intermediate (10-50 %), and high (>50 %). The association between PET/MRI findings and TILs was assessed using Kruskal-Wallis test and Wilcoxon signed-rank test. RESULTS: There were 14 high TIL, 20 intermediate TIL and 21 low TIL lesions. Higher values of SUVmax were found in the high and intermediate TIL group as compared to the low TIL group (P = 0.013). On the other hand, the lesions with peritumoral edema in the low TIL group tended to show high SUVmax (P = 0.014). CONCLUSIONS:18F-FDG uptake on PET/MRI correlated with TIL levels in patients with TNBC and HER2-positive breast cancer. This finding suggests that preoperative PET/MRI may be useful as a non-invasive tool for guiding the treatment plan.