(18)F-FDG PET/CT is a sensitive and specific imaging modality for identifying distant metastases in patients with LABC missed by conventional imaging. In addition, it detects unknown lymph nodal metastases in a significant proportion of patients and hence can be used routinely in staging of patients with LABC.

Introduction:Treatment of cervical cancer is usually surgery in the early stages and radiotherapy or chemoradiotherapy in more advanced stages of the disease. Recurrence may occur in multiple sites following primary treatment. Although recurrent metastatic disease is not curable, surgical treatment may be of great help if locoregional recurrence is detected early. Fluorine-18 Fluorodeoxyglucose positron emission tomography - computed tomography (F-18 FDG PET/CT) forms an important part of investigations in the diagnosis of clinically suspicious recurrent cervical cancer.Objective:To assess the role of F-18 FDG PET/CT in diagnosing recurrence in patients with clinical suspicion of recurrent cervical cancer.Materials and Methods:We retrospectively evaluated 53 histopathologically proved patients of cervical cancer. All the patients had been treated with either surgery/radiation therapy with or without chemotherapy. The standard PET/CT acquisition protocol, with delayed post void static pelvic images, wherever required, was followed in all patients. Significant uptake of FDG in the lymph nodes was considered to be a recurrence suggestive of metastasis. Para-aortic lymph nodal involvement was considered to be distant metastasis. Any significant uptake in the lung nodule on FDG PET was evaluated either by histological confirmation, by taking fine needle aspiration cytology (FNAC), or by a follow-up chest CT done after three months.Results:Of the 53 patients with clinically equivocal recurrence, FDG PET/CT suggested recurrence in 41 patients (local recurrence in 14 patients and distant recurrence/metastasis with or without local recurrence in 27 patients). It had a sensitivity of 97.5%, a specificity of 63.6%, positive predictive value of 90.9%, and negative predictive value of 87.5%.Conclusion:PET/CT appears to have an important role in detecting recurrence following primary treatment of cervical cancer. The high positive and negative predictive values of PET/CT may be helpful in planning management of recurrent cervical cancer.

Treatment of Graves' disease with iodine-131 (131I) is well-known; however, all patients do not respond to a single dose of 131I and may require higher and repeated doses. This study was carried out to identify the factors, which can predict treatment failure to a single dose of 131I treatment in these patients. Data of 150 patients with Graves' disease treated with 259-370 MBq of 131I followed-up for at least 1-year were retrospectively analyzed. Logistic regression analysis was used to predict factors which can predict treatment failure, such as age, sex, duration of disease, grade of goiter, duration of treatment with anti-thyroid drugs, mean dosage of anti-thyroid drugs used, 99mTc-pertechnetate (99mTcO4-) uptake at 20 min, dose of 131I administered, total triiodothyronine and thyroxine levels. Of the 150 patients, 25 patients required retreatment within 1 year of initial treatment with 131I. Logistic regression analysis revealed that male sex and 99mTcO4- uptake were associated with treatment failure. On receiver operating characteristic (ROC) curve analysis, area under the curve (AUC) was significant for 99mTcO4- uptake predicting treatment failure (AUC = 0.623; P = 0.039). Optimum cutoff for 99mTcO4- uptake was 17.75 with a sensitivity of 68% and specificity of 66% to predict treatment failure. Patients with >17.75% 99mTcO4- uptake had odds ratio of 3.14 (P = 0.014) for treatment failure and male patients had odds ratio of 1.783 for treatment failure. Our results suggest that male patients and patients with high pre-treatment 99mTcO4- uptake are more likely to require repeated doses of 131I to achieve complete remission.