Special Relevance of FDG-PET as an Upfront Diagnostic Modality at Initial Diagnosis and in Suspected Recurrence in Patients of Breast Carcinoma Hailing From Lower Socioeconomic Status Owing to Relative Late Presentation: A Pilot Study in a Medical College Hospital Setting in India

摘要

FDG-PET has found relatively limited use in routine management of breast carcinoma due to its limited utility in assessing the primary and axillary lymph node status. The aim of the study was to assess its role in a medical school and municipal hospital setting of Mumbai, where majority belongs to the lower socioeconomic status and presents relatively late and hence whole body FDG-PET could find important place for assessing whole body disease status that would justify being used upfront in this group of patients. Thus, the premise of this study was that FDG-PET will have special relevance in this particular setting for evaluation of patients of breast carcinoma with respect to initial staging, detection of locoregional recurrence and metastasis and assessing response to systemic treatment. A total of 52 patients proven to have breast carcinoma, who had undergone 18F FDG–PET for disease staging at initial diagnosis and in in recurrent disease staging with a few cases as a baseline study for early treatment monitoring purposes over a study period of 3?years, were included in this analysis. 33.3?% of patients with pretreatment baseline FDG-PET were upstaged with diagnosis of additional lesions in the adrenal gland, liver, internal mammary, cervical lymph nodes and the mediastinum. On a lesion specific analysis, the percentage of increased lesion detection (including both lymph node with distant metastasis) by FDG-PET was 42.7?%. FDG-PET was found to be 100?% sensitive and specific for confirming recurrent breast cancer. Four out of 18 patients on chemotherapy underwent second FDG-PET after first cycle of chemotherapy, showed responsiveness to chemotherapy by decreased maximum standardized uptake value (SUVmax). FDG-PET showed 9 liver lesions in 6 patients, only 3 of them was reported in USG. In one patient USG abdomen was inconclusive between hemangioma and metastasis, FDG-PET ruled out liver metastasis in this patient. In the examined patient population belonging to lower socioeconomic status, where usual presentation is relatively late, upfront whole body survey with FDG-PET or PET/CT is of considerable value in view of higher probability of existence of metastatic disease, thus can be an important one-stop shop tool in assessing whole body disease status in a single examination. It also proved efficacious in diagnosing loco regional and distant recurrence, metabolic characterization of lump and early response to treatment in the examined few cases following one cycle of chemotherapy in locally advanced breast cancer.