Indications and usage▾
1 INDICATIONS AND USAGE Choline C 11 Injection is indicated for positron emission tomography (PET) imaging of patients with suspected prostate cancer recurrence and non-informative bone scintigraphy, computerized tomography (CT) or magnetic resonance imaging (MRI). In these patients, 11 C-choline PET imaging may help identify potential sites of prostate cancer recurrence for subsequent histologic confirmation. Suspected prostate recurrence is based upon elevated blood prostate specific antigen (PSA) levels following initial therapy. In clinical studies, images were produced with PET/CT coregistration. Limitation of U se: 11 C-choline PET imaging is not a replacement for histologic verification of recurrent prostate cancer. Choline C 11 Injection is a radioactive diagnostic agent for positron emission tomography (PET) imaging of patients with suspected prostate cancer recurrence and non-informative bone scintigraphy, computerized tomography (CT) or magnetic resonance imaging. In these patients, 11 C-choline PET imaging may help identify potential sites of prostate cancer recurrence for subsequent histologic confirmation. Suspected prostate recurrence is based upon elevated blood prostate specific antigen (PSA) levels following initial therapy. In clinical studies, images were produced with PET/CT coregistration. Limitation of U se: 11 C-choline PET imaging is not a replacement for histologic verification of recurrent prostate cancer ( 1 ).
Dosage and administration▾
2 DOSAGE AND ADMINISTRATION Aseptically withdraw Choline C 11 Injection from its container and administer 370 – 740 MBq (10 – 20 mCi) as a bolus intravenous injection. The radioactivity dose (370 – 740 MBq, 10 – 20 mCi) is chosen based on patient body dimensions and the characteristics of the image acquisition system ( 2.1 ). Initiate imaging immediately after administration of Choline C 11 Injection and acquire static emission images 0 – 15 minutes from the time of injection ( 2.5 ). The effective radiation absorbed dose from 740 MBq (20 mCi) dose of Choline C 11 Injection is approximately 3.22 mSv (0.32 rem) in an adult ( 2.4 ). Image interpretation: Refer to full prescribing information ( 2.5 ). 2.1 Radiation Safety – Drug Handling Choline C 11 Injection is a radioactive drug and should be handled with appropriate safety measures to minimize radiation exposure during administration. Use waterproof gloves and effective shielding when handling Choline C 11 Injection. Radiopharmaceuticals, including Choline C 11 Injection, should only be used by or under the control of physicians who are qualified by specific training and experience in the safe use and handling of radioactive materials, and whose experience and training have been approved by the appropriate governmental agency authorized to license the use of radionuclides. 2.2 Recommended Dose and Administration Instructions The recommended dose is 370 – 740 MBq (10 – 20 mCi) administered as a bolus intravenous injection. The radioactivity dose (370 – 740 MBq, 10 – 20 mCi) is chosen based on patient body dimensions and the characteristics of the image acquisition system Inspect Choline C 11 Injection visually for particulate matter and discoloration before administration. Do not use the drug if the solution contains particulate matter or is discolored. Aseptically withdraw Choline C 11 Injection from its container and administer the drug as a bolus through a peripheral venous catheter. Dispose of any unused drug in a safe manner, in compliance with applicable regulations. 2.3 Patient Preparation Prior to administration of Choline C 11 Injection: Fasting for at least six hours is recommended to minimize the potential for dietary choline interference with radioactivity uptake in tissue. Ensure that the patient is well hydrated and encourage voiding when imaging is completed. 2.4 R adiation Dosimetry The estimated radiation absorbed doses for adults from intravenous injection of Choline C 11 Injection are shown in Table 1. These estimates are calculated from data in Tolvanen 1 and using OLINDA/EXM (Organ Level Internal Dose Assessment/Exponential Modeling) software from Vanderbilt University. 2 Table 1: Estimated Radiation Absorbed Dose Per Unit Activity for Adults, Choline C 11 Injection Organ/Tissue Mean Absorbed Dose P er Unit Administered Activity ( μ Gy/MBq) b Adrenals 3.59 Bone - Osteogenic Cells 4.81 Bone - Red Marrow 1.90 Brain 1.16 Breast 1.39 Gallbladder Wall 4.54 GI a – Lower Large Intestine Wall 1.81 GI a - Small Intestine 2.35 GI a - Stomach Wall 6.00 GI a – Upper Large Intestine Wall 6.41 Heart wall 3.43 Kidneys 20.62 Liver 20.11 Lungs 4.59 Muscle 2.54 Ovaries 2.02 Pancreas 29.19 Skin 1.22 Spleen 9.16 Testes 1.36 Thymus 1.69 Thyroid 1.49 Urinary Bladder Wall 3.41 Uterus 1.96 Total body 2.97 Effective Dose (μSv/MBq) c 4.35 a Gastrointestinal b Assumed radiation weighting factor, w r , (formerly defined as quality factor, Q) of 1 for conversion of absorbed dose (Gray or rad) to dose equivalent (Sieverts or rem) for C 11. To obtain radiation absorbed dose in rad/mCi from the above table, multiply the dose in μGy/MBq by 0.0037, (e.g., 3.59 μGy/MBq × 0.0037 = 0.0133 rad/mCi). c Radiation tissue weighting factors, w T , used in the calculation of effective dose are from 1990 Recommendations of the International Commission on Radiological Protection, ICRP Publication 60 (1991). To obtain radiation absorbed dose in rem/mCi from above table, multiply the dose in μGy/MBq by 0.0037, (e.g., 4.35 μGy/MBq × 0.0037 = 0.0161 rem/mCi). The effective dose resulting from a 740 MBq (20 mCi) dosage of Choline C 11 Injection is 3.22 mSv in an adult, (740 × 4.35 = 3219 μSv = 3.2 mSv). The use of a CT scan to calculate attenuation correction for reconstruction of 11 C-choline images (as done in PET/CT imaging) will add radiation exposure. Based upon current scanning techniques, an effective dose of 5.8 mSv would be added from CT scanning. The actual radiation dose is operator, scanner, and patient dependent. The total radiation exposure from 11 C-choline administration and subsequent scan on a PET/CT scanner is estimated to be 9.0 mSv (3.2 mSv + 5.8 mSv). 2.5 Imaging Guidelines Initiate image acquisition immediately after administration of Choline C 11 Injection. Imaging is typically performed from the base of the pelvis to the base of the skull. Acquire static emission images 0 – 15 minutes from the time of injection. Localized uptake of 11 C-choline in a site suspicious for prostate cancer recurrence (a positive image) is determined by comparison of the anatomical relationship of concentrated radioactivity to the neighboring tissue background, exclusive of the radioactivity physiologically accumulated within the pancreas, liver, spleen, kidney and colon.
Contraindications▾
4 CONTRAINDICATIONS None. None ( 4 ).
Warnings and precautions▾
5 WARNINGS AND PRECAUTIONS Imaging errors have been reported; blood PSA levels < 2 ng/mL have been associated with poor imaging performance ( 5.1 ). Allergic reactions: have emergency resuscitation equipment and personnel readily available ( 5.2 ). Radiation risk: Choline C 11 Injection contributes to a patient’s long-term cumulative radiation exposure. Ensure safe handling to protect the patient and health care worker ( 5.3 ). 5.1 Imaging Errors Imaging errors have been reported with 11 C-choline PET and PET/CT imaging. A negative image does not rule out the presence of recurrent prostate cancer and a positive image does not confirm the presence of recurrent cancer. 11C-choline uptake is not specific for prostate cancer and may occur with other types of cancer (such as lung carcinoma and brain tumors). Clinical correlation, including histopathological evaluation of the suspected recurrence site, is essential to proper use of the PET imaging information. Blood PSA levels < 2 ng/mL have been associated with poor performance of 11 C-choline PET imaging (higher numbers of false positive and false negative results) [see Clinical Studies (14) ] . Tissue inflammation as well as prostatic hyperplasia have been associated with false positive 11 C-choline PET images. Concomitant colchicine or androgen-deprivation therapeutic drugs (such as luteinizing hormone-releasing analogs and anti-androgen drugs) may interfere with 11 C-choline PET imaging. One published report of 18 F-methylcholine PET imaging indicated that discontinuation of colchicine for two weeks resolved the colchicine effect. The impact of discontinuation of androgen-deprivation therapy upon 11 C-choline PET imaging has not been established [see Drug Interactions (7) ] . 5.2 Allergic Reactions As with any injectable drug product, allergic reactions and anaphylaxis may occur. Emergency resuscitation equipment and personnel should be immediately available. 5.3 Radiation Risks Choline C 11 Injection contributes to a patient’s overall long-term cumulative radiation exposure. Long-term cumulative radiation exposure is associated with an increased risk for cancer. Safe handling should be ensured to minimize radiation exposure to the patient and health care workers [ see Dosage and Administration (2.1) ].
Drug interactions▾
7 DRUG INTERACTIONS Colchicine and androgen-deprivation therapeutic drugs have been reported to interfere with choline-based PET imaging [ see Warnings and Precautions (5.1) ]. The impact of androgen-deprivation therapeutic drugs upon 11 C-choline PET imaging may depend upon the hormonal responsiveness of a patient’s recurrent prostate cancer. Clinical studies have not established this relationship but published reports suggest 11 C-choline PET imaging may be productive in patients with “hormone resistant” recurrent prostate cancer even if the patients are receiving anti-androgen therapy. Imaging may prove unproductive or misleading due to failed or insufficient 11 C-choline uptake in patients with hormone-responsive cancer if the patients are receiving androgen-deprivation therapy. Colchicine and androgen-deprivation therapeutic drugs may interfere with 11 C-choline PET/CT imaging performance ( 5.1 ).
Adverse reactions▾
6 ADVERSE REACTIONS Exclusive of an uncommon, mild injection site reaction, no adverse reactions to 11 C-choline have been reported. Exclusive of an uncommon, mild injection site reaction, no other adverse reactions have been reported ( 6 ). To report SUSPECTED ADVERSE REACTIONS, contact Division of Nuclear Medicine, Department of Radiology, Mayo Clinic at 507-284-2511 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch
Use in pregnancy▾
8.1 Pregnancy Pregnancy Category C. There are no adequate and well controlled studies with Choline C 11 Injection in pregnant women and the fetal radiation dose from a 11 C-choline PET imaging study is unknown. It is not known whether Choline C 11 Injection can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Animal reproduction studies have not been conducted with 11 C-choline. All radiopharmaceuticals, including Choline C 11 Injection, have a potential to cause fetal harm. The likelihood of fetal harm depends on the stage of fetal development and the magnitude of the radiopharmaceutical dose. Assess pregnancy status before administering Choline C 11 Injection to a female of child bearing potential. Choline C 11 Injection should be given to a pregnant woman only if clearly needed.
Label text is reproduced as-is from the FDA-approved label. We do not paraphrase, summarize, or omit. Content above is for informational purposes only and is not medical advice. Always consult your prescribing clinician or pharmacist before making decisions about your medication.