F-18 fluorodeoxyglucose positron emission tomography/computed tomography in conjunctival melanoma with recurrence.

Ocular melanoma is classified under the category of noncutaneous melanomas. Noncutaneous melanomas are relatively rare. Ocular melanoma commonly arises from choroid. Conjunctival melanoma is a rare but potentially lethal form of ocular melanoma. It can invade locally. Systemic spread is seen in up to 25% of cases, often associated with lymph node involvement. Metastatic sites include the lungs, liver, gastrointestinal tract, and the central nervous system. F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET-CT) scanning is indicated for staging cutaneous melanoma patients. However, few studies have evaluated its role in the management of conjunctival melanoma. This case highlights the use of F-18 FDG PET/CT for imaging, preoperative staging, and evaluation for metastasis in conjunctival melanoma.

Dacroscintigraphy by Pediatric Dropper Technique: A User-friendly Instillation Procedure of Radiotracer.

CONTEXT: Instillation or application of the radiotracer over the tear film is one of the important parts of dacroscintigraphy. Our study explains the value of an improvised dropper technique so that desired amount of radioactivity in desired volume can be instilled over the tear film. AIM: The aim of the study is to introduce a simple and convenient instillation method based on dropper technique for performing dacroscintigraphy. This improvised dropper technique can be used so that desired amount of radioactivity in desired volume can be instilled over the tear film. The objectives of this experiment are to measure the volume and activity of each drop from the dropper. SETTINGS AND DESIGN: Experiment of volume and activity measurement standardization was carried out in two parts. In the first part, we calculated the volume of each drop indirectly to standardize the volume of drop. In the second part, we standardized the activity in each drop by measuring it in a dose calibrator. SUBJECTS AND METHODS: In this study, we used a common pediatric dropper of approximately 1 ml capacity, radioactivity (99mTcO4 pertechnetate), sample vial (container), vial holder, a pair of nonsterile gloves, dose calibrator, etc., Experiments of volume and radioactivity standardization were carried out in two parts. The first part of experiment calculated volume of each drop indirectly, and in the second, we standardized the activity in each drop by measuring it in dose calibrator. Statistical analysis used: Analysis of variance test was used to calculate the correlation of readings by same individual as well as among the three individuals. RESULTS: After analysis of result obtained, it was understood that there was no significant difference found in volume and activity of each drop in the readings recorded by same individual as well as among the three individuals. The calculated activity and observed activity were 86.64 and 79.16 µCi, respectively. The difference was only 8.63% lying within acceptable limits.

Tumor characteristics and metabolic quantification in carcinoma breast: An institutional experience.

BACKGROUND: In India, carcinoma breast is the most common cancer among urban women population and second most common cancer after carcinoma cervix in rural areas. One in 22 women in India develops carcinoma of the breast in their lifetime. Fluorine-18-fluoro-2-deoxy-D-glucose (18F-FDG) uptake in breast cancer usually indicates the degree of tumor metabolism and hence can predict its behavior and prognosis. On the other hand, the estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER-2) or neu state of breast cancer is a biomarker that provides important prognostic information in addition to predicting response to therapy. AIMS: The main objective of this study is to assess whether a correlation exists between 18F-FDG uptake in untreated cases of breast cancer, their receptor status (ER, PR, and HER-2 or neu), tumor histology, and tumor size. SUBJECTS AND METHODS: Sixty consecutive female patients, with biopsy-proven primary breast cancer, were enrolled in this prospective study for whom 18F-FDG positron emission tomography-computed tomography scan was done in the Department of Nuclear Medicine. Results obtained were analyzed using appropriate statistical tests (t-test and Pearson Chi-square tests), and interpretation was made with 95% confidence level. RESULTS: In our series, a positive correlation between tumor size, high tumor grade, and standardized uptake value (SUV) was found. Tumors with positive receptor status for estrogen, progesterone, and HER-2/neu receptors had statistically insignificant lower maximum SUV (SUVmax) values than their negative counterparts. Triple-negative breast tumors (ER-, PR-, and no overexpression of HER-2/neu) are currently a subject of major interest because of their aggressiveness, poor prognosis, and lack of targeted therapy. Based on receptor status when the SUVmaxof the group with triple-negative receptor status (ER-/PR-/HER-2/neu-) was compared to rest of the patient group, it was seen that patients with negative receptor status had significantly higher mean SUVmaxvalues. CONCLUSIONS: We have inferred that in patients with breast cancer, various biological parameters such as tumor size, grade, histology, and hormonal receptor status have different impact on tumor metabolic activity.