Breast Scintigraphy Procedure Guideline Version 2.0 PDF

Society of Nuclear Medicine Procedure Guideline for Breast Scintigraphy Version 2.0, approved June 2, 2004 Authors: Iraj Khalkhali, MD (Harbor-UCLA Medical Center, Torrance, CA); Gina Caravaglia, MD (Harbor-UCLA Medical Center, Torrance, CA); Hani H. Abdel-Nabi, MD, PhD (University of Buffalo, Buff...

Society of Nuclear Medicine Procedure Guideline for Breast Scintigraphy Version 2.0, approved June 2, 2004 Authors: Iraj Khalkhali, MD (Harbor-UCLA Medical Center, Torrance, CA); Gina Caravaglia, MD (Harbor-UCLA Medical Center, Torrance, CA); Hani H. Abdel-Nabi, MD, PhD (University of Buffalo, Buffalo, NY); Patrick J. Peller, MD (Woodburn Nuclear Medicine, Annandale, VA); Raymond Taillefer, MD (Hospital Hotel-Dieu de Montreal, Montreal, Quebec, Canada); Penny R. Vande Streek, DO (Sutter Roseville Medical Center, Roseville, CA); and Christophe Van de Wiele, MD (Universitair Ziekenhuis, Ghent, Belgium). I. Purpose carcinomas in patients with tissue diagnosis of breast cancer. The purpose of this guideline is to assist nuclear C. May be useful in the evaluation of the effective- medicine practitioners in recommending, performing, ness of neoadjuvant chemotherapy for breast car- interpreting, and reporting the results of 99mTc- cinoma. sestamibi breast scintigraphy (mammoscintigraphy, scintimammography). IV. Procedure II. Background Information and Definitions A. Patient Preparation 1. No special preparation for the test is needed; Breast scintigraphy is performed after intravenous however, a thorough explanation of the test administration of 99mTc-sestamibi and includes planar should be provided by the technologist or and/or single-photon emission computed tomography physician. Before radiopharmaceutical injec- (SPECT). tion, the technologist may have the patient at- tempt the prone position with arms extended, III. Examples of Clinical or Research to assess the feasibility of the study. Applications 2. The patient should remove all clothing and jewelry above the waist and should wear a A. Evaluate breast cancer in patients in whom hospital gown open in front. mammography is nondiagnostic, equivocal, or B. Information Pertinent to Performing the Pro- difficult to interpret (e.g., the presence of scar tis- cedure sue, mammographically dense breast tissue, im- 1. Prior mammograms should be available, as plants, or severe dysplastic disease). well as prior ultrasound and MRI, if per- B. Assist in identifying multicentric and multifocal formed. The Society of Nuclear Medicine (SNM) has written and approved these guidelines as an educational tool designed to promote the cost- effective use of high-quality nuclear medicine procedures or in the conduct of research and to assist practitioners in providing appropriate care for patients. The guidelines should not be deemed inclusive of all proper procedures nor exclusive of other procedures reasonably di- rected to obtaining the same results. They are neither inflexible rules nor requirements of practice and are not intended nor should they be used to establish a legal standard of care. For these reasons, SNM cautions against the use of these guidelines in litigation in which the clini- cal decisions of a practitioner are called into question. The ultimate judgment about the propriety of any specific procedure or course of action must be made by the physician when considering the circumstances presented. Thus, an approach that differs from the guidelines is not necessarily below the standard of care. A conscientious practitioner may responsibly adopt a course of action different from that set forth in the guidelines when, in his or her reasonable judgment, such course of action is indicated by the condition of the patient, limitations on available resources, or advances in knowledge or technology subsequent to publication of the guidelines. All that should be expected is that the practitioner will follow a reasonable course of action based on current knowledge, available resources, and the needs of the patient to deliver effective and safe medical care. The sole purpose of these guidelines is to assist practitioners in achiev- ing this objective. Advances in medicine occur at a rapid rate. The date of a guideline should always be considered in determining its current applicability. 2 z BREAST SCINTIGRAPHY 2. A breast physical examination must be per- 4. Radiation dosimetry formed by either the nuclear medicine physi- E. Image Acquisition cian or the referring physician. A copy of the 1. Instrumentation physical examination performed by the refer- a. A standard scintillation camera is ring physician should be a part of the nuclear equipped with a low-energy, high-resolu- medicine referral jacket. tion collimator. 3. The time of last menses and pregnancy and b. A symmetric 10% energy window should lactating status of the patient should be deter- be centered over the 140-keV photopeak mined. If the patient is pregnant or lactating, of 99mTc. then determination should be made as to 2. Patient Position whether to proceed with the examination. If a. The patient lies prone with the breast to be so, appropriate radiation safety recommenda- imaged dependent from the imaging table. tions should be provided for the patient. The contralateral breast should be com- 4. Breast scintigraphy should be delayed at least pressed against the table to prevent cross- 2 wk after a cyst aspiration or fine needle as- talk of activity. A breast-positioning de- piration, and 4–6 wk after a core or excisional vice (table adapter, foam pad, etc.) should biopsy. This procedure can produce false- be used to minimize patient motion. The positive results if performed within 4–6 wk af- arms should be raised to expose the axil- ter core or excisional biopsy. lae. The head should be turned away from 5. The nuclear medicine physician should be the detector to minimize shine-through of aware of physical signs and symptoms and normal head and neck activity. prior surgical procedures or therapy. b. The detector should touch the patient’s C. Precautions side for improved resolution. Known hypersensitivity to 99mTc-sestamibi should c. The anterior image may be acquired with be noted. the patient supine or upright. D. Radiopharmaceutical 3. Images 1. Intravenous injection of 740–1,110 MBq (20– a. Imaging begins 5–10 min after administra- 30 mCi) 99mTc-sestamibi should be adminis- tion of the radiopharmaceutical. tered in an arm vein contralateral to the breast b. Planar images are acquired for 10 min with the suspected abnormality. If the disease each, using a 128 × 128 or larger matrix to is bilateral, the injection is ideally adminis- allow for pixel overload that may come tered in a foot vein. from the liver, heart, etc. 2. The radiopharmaceutical should be adminis- c. The following planar images should be tered using an indwelling catheter or butterfly acquired: needle. The radiopharmaceutical should be i. Prone lateral image of the breast with followed by 10 cc of saline to flush the vein. the suspected abnormality. The field of 3. Normal distribution of the radiopharmaceuti- view should include the breast, axilla, cal includes the salivary and thyroid glands, and anterior chest wall, excluding any myocardium, liver, gallbladder, small and internal organ activity. Electronic mag- large intestine, kidneys, bladder, and skeletal nification should be used as needed to muscles. optimize pixel size. Radiation Dosimetry: Adults* Radiopharmaceutical Administered Organ receiving the Effective dose activity largest radiation dose MBq mGy/MBq mSv/MBq (mCi) (rad/mCi) (rem/mCi)) 740–1,110 iv 0.039 0.0085 99m Tc-sestamibi Gallbladder (20–30) (0.14) (0.031) *International Commission on Radiological Protection. Radiation Protection in Biomedical Research. ICRP Publication 62. New York, NY: Pergamon Press; 1993:23.  SOCIETY OF NUCLEAR MEDICINE PROCEDURE GUIDELINES z 3 ii. If needed, prone posterior oblique im- H. Interpretation Criteria age of the ipsilateral breast. The detec- 1. Focal increased uptake of the radiopharma- tor is moved 30º posterior of lateral. ceutical in the breast or axilla (in the absence iii. Prone lateral and, if needed, posterior of radiopharmaceutical infiltration) is suspi- oblique images of the contralateral cious for malignancy. breast. 2. Mild homogeneous uptake of the radiophar- iv. Anterior supine or upright chest image. maceutical in the breast or axilla is consistent The anterior upright or supine image with a normal study. should include both breasts and both 3. Patchy or diffuse increased radiopharmaceuti- axillae in the field of view. Arms cal uptake in the breasts is probably not con- should be raised (for upright anterior sistent with malignancy. view) or extended (for prone anterior 4. There is a great variability of intensity of focal view) to expose the axillary regions. uptake. The following image features are Do not use zoom in anterior position if more suspicious of breast malignancy: focal the camera system does not allow increased uptake, relatively well-delineated breasts and both axillae in the image. contours, with mild-to-intense radiotracer up- d. The use of radioactive markers over pal- take; focal increased uptake (1 or more foci) pable abnormalities is optional. A set of in the ipsilateral axilla, in the presence of a anterior planar images of the thorax can be primary lesion in the breast is strongly sugges- made to provide more accurate anatomical tive of axillary lymph node metastatic in- location using radioactive markers placed volvement. Note that a linear and superficial at the nipples. If markers are placed, they axillary uptake on the lateral thoracic views must be placed after patient is positioned usually corresponds to uptake in skin folds. in prone position. The location of the The following image features are more sug- breast lesion in relation to the marker may gestive of a benign disease of the breast: dif- change significantly if the markers are fuse or patchy radiotracer uptake of mild to placed in supine or upright position and moderate intensity, often bilateral, edges are then the breast is positioned in prone lat- not visually well defined. eral. I. Reporting e. No consensus has been reached regarding The report to the referring physician should the utility of SPECT imaging; therefore, recommend correlation with clinical findings, no parameters for SPECT imaging or as well as the results of other imaging studies. processing are included here. J. Quality Control F. Interventions 1. Routine scintillation camera quality control None. should be performed as described in the Soci- G. Processing ety of Nuclear Medicine Procedure Guideline 1. Masking of the high-activity chest and ab- for General Imaging. dominal organs, such as the myocardium 2. Quality control measures and radiation safety and liver, from the final images will im- precautions should be followed as described prove visualization of breast tissue. This in the Society of Nuclear Medicine Procedure masking may be performed using regions of Guideline for Use of Radiopharmaceuticals. interest generated on the computer or by K. Sources of Error count subtraction. Both the masked and 1. Infiltration of the radiopharmaceutical admin- original images should be included in the istered in an arm vein may cause false-posi- final display. tive uptake in the axillary lymph nodes. Inclu- 2. Interpretation of the images should be done sion of an injection site may be helpful in from the computer monitor whenever possi- evaluating the presence and extent of dose in- ble, because adjustment of the image contrast filtration, which may be particularly important by the interpreting physician may be neces- if an unsuspected contralateral breast lesion is sary. discovered. 3. A logarithmic scale to enhance low-count ar- 2. Patient positioning that does not allow the eas instead of a linear scale is preferable for breast to be fully dependent will decrease the image display. accuracy of the test. 4. Grayscale is preferable to color for interpreta- 3. Patient motion will decrease the accuracy of tion. the test. 4 z BREAST SCINTIGRAPHY 4. If both breasts are dependent, cross-talk of ac- nosis of breast lesions. J Nucl Med. 1997;38:58– tivity may result in a false-positive result in 62. the contralateral breast. I. Villanueva-Meyer J, Leonard MH, Briscoe E, et 5. The sensitivity, specificity, and accuracy of al. Mammoscintigraphy with technetium-99m- this test depend upon several factors, includ- sestamibi in suspected breast cancer. J Nucl Med. ing the size of the breast tumor being imaged. 1996;37:926–930. The sensitivity of this test for tumors smaller than 1 cm in diameter is very low with nuclear medicine cameras in current use. V. Issues Requiring Further Clarification A. Further study is needed to determine the charac- teristics of the population most likely to benefit from breast scintigraphy. B. No consensus has been reached as to the efficacy of routine SPECT imaging. C. The usefulness of other radiopharmaceuticals for breast scintigraphy has not been established. D. The usefulness of breast scintigraphy for all indi- cations included here requires further study. VI. Concise Bibliography A. Cutrone J, Shane-Yospur L, Khalkhali I, et al. Immunohistologic assessment of Tc-99m sestamibi uptake in benign and malignant breast lesions. J Nucl Med. 1998;39:449–453. B. Del Vecchio S, Ciarmiello A, Pace L, et al. Frac- tional retention of technetium-99m-sestamibi as an index of p-glycoprotein expression in un- treated breast cancer patients. J Nucl Med 1997;38:1348–1351. C. Diggles L, Mena I, Khalkhali I. Technical aspects of prone dependent-breast scintimammography. J Nucl Med Technol. 1994;22:165–170. D. Khalkhali I, Mena I, Jouanne E, et al. Prone scin- timammography in patients with suspicion of breast cancer. J Am Coll Surg. 1994;178:491– 497. E. Palmedo H, Schomburg A, Grunwald F, et al. Scintimammography with Tc-99m MIBI in pa- tients with suspicion of primary breast cancer. Nucl Med Biol. 1996;23:681–684. F. Peller P, Khedkar N, Martinez C. Breast tumor scintigraphy. J Nucl Med Technol. 1996;24:198– 203. G. Taillefer R, Robidoux A, Lambert R, et al. Tech- netium-99m-sestamibi prone scintimammography to detect primary breast cancer and axillary lymph node involvement. J Nucl Med. 1995; 36:1758– 1765. H. Tiling R, Sommer H, Pechmann M, et al. Com- parison of technetium-99m-sestamibi scintimam- mography with contrast-enhanced MRI for diag-