Intraductal Papilloma With Carcinoma of the Breast Described by Dedicated Breast 18F-FDG PET.

ABSTRACT: Intraductal papilloma (IDP) is a benign tumor of the breast. However, IDP has been reported to show high uptake of 18F-FDG using whole-body PET. We experienced IDP with low-grade ductal carcinoma in situ using dedicated breast PET, which is more sensitive than whole-body PET. The 18F-FDG uptake of the whole tumor was high, and differentiation between the carcinoma and the residual benign lesion was difficult. This is the first report of IDP detected with dedicated breast PET. Diagnosis of IDP is sometimes controversial; papilloma may show glucose uptake similar to that of low-grade carcinoma.

Evaluation of the Response to Breast Cancer Neoadjuvant Chemotherapy Using 18F-FDG Positron Emission Mammography Compared With Whole-Body 18F-FDG PET: A Prospective Observational Study.

PURPOSE: The aim of this study was to assess therapeutic response to breast cancer neoadjuvant chemotherapy (NAC) by F-FDG positron emission mammography (PEM) compared with that to whole-body F-FDG PET (WBPET). METHODS: Twenty patients underwent WBPET and PEM 3 times: the first time was before NAC, the second time was after 2 courses of NAC, and the third time was after all courses of NAC. A pathological complete response (pCR) was defined as no evidence of residual invasive cancer with or without ductal carcinoma in situ. The relationships between each modality's SUVmax and pathological response were evaluated. RESULTS: Nine patients achieved a pCR, whereas the other 11 patients had a non-pCR. The SUVmax of WBPET after 2 courses of NAC was significantly lower in the pCR group than in the non-pCR group (1.4 ± 0.4 vs 2.7 ± 2.1, P = 0.0334). There were no significant differences in the SUVmax of PEM (ie, PEM uptake value [PUV]) between the groups. The SUVmax of WBPET (area under the ROC curve [AUC] = 0.761) was superior to the PUVmax (AUC, 0.648) for predicting non-pCR at the interim time point. After all courses of chemotherapy, there were no significant differences between the groups in the SUVmax of WBPET; however, PUVmax was significantly lower in the pCR group than in the non-pCR group (1.0 ± 0.2 vs 2.5 ± 2.7, P = 0.0351). After NAC, the PUVmax (AUC, 0.796) was superior to the SUVmax of WBPET (AUC, 0.671). CONCLUSIONS: There proved to be no apparent superiority of PEM in predicting pCR at the interim time point. Positron emission mammography had greater diagnostic capability for detecting residual cancer after all courses of NAC.

Positron emission mammography (PEM): reviewing standardized semiquantitative method.

PURPOSE: To validate semiquantitative analysis of positron emission mammography (PEM). METHODS: Fifty women with histologically confirmed breast lesions were retrospectively enrolled. Semiquantitative uptake values (4 methods), the maximum PEM uptake value (PUVmax), and the lesion-to-background (LTB) value (3 methods) were measured. LTB is a ratio of the lesion's PUVmax to the mean background; LTB1, LTB2, and LTB3 (which were calculated on different background) were used to designate the three values measured. Interobserver reliability between two readers for PUVmax and the LTBs was tested using the interobserver correlation coefficient (ICC). The likelihood ratio test was used to evaluate the relationship between ICCs. Receiver operating characteristic (ROC) curves were calculated for all methods. Diagnostic accuracy in differentiating benign tissue from malignant tissue was compared between PUVmax and LTB1. RESULTS: The ICC rate was 0.971 [95 % confidence interval (CI) 0.943-0.986] for PUVmax, 0.873 (95 % CI 0.758-0.935) for LTB1, 0.965 (95 % CI 0.925-0.983) for LTB2, and 0.895 (95 % CI 0.799-0.946) for LTB3. However, there were some technical difficulties in the practical use of LTB2 and LTB3. The likelihood ratio test between PUVmax and LTB1 was statistically significant (p < 0.001). ROC curves of the 4 methods had similar characteristics. The median PUVmax was 1.39 for benign lesions and 3.70 for malignant lesions. LTB1 was 1.92 for benign lesions and 4.78 for malignant lesions. Significant differences (p < 0.001) in both PUVmax and LTB1 were observed between groups. CONCLUSION: Due to its simplicity and reproducibility, PUVmax is superior to LTB as an indicator for PEM in semiquantitative analysis.