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Methodological aspects of 99m Tc-sestamibi guided biopsy in breast cancer

View Article: PubMed Central - PubMed

ABSTRACT

Purpose: This review aims to discuss the methodological aspects of dedicated molecular breast imaging (MBI) using 99mTc-sestamibi as radiotracer to guide biopsy of occult or unclear breast lesions on mammography (MG) and ultrasound (US) that are suspicious on MBI (BI-RADS criteria 4 and 5), including its advantages, limitations and future clinical applications.

Methods: Literature search was performed using the PubMed/MEDLINE database and “99mTc-sestamibi”, “biopsy” and “breast cancer” as keywords. The search was restricted to English language.

Results: There are few studies on 99mTc-sestamibi guided biopsy methods; to our knowledge, no full studies have yet been reported on clinical validation of this new biopsy procedure. This review describes technical aspects of 99mTc-sestamibi guided biopsy and discusses the advantages and limitations of this procedure in comparison with MG, US and MRI-guided biopsy.

Conclusions: MBI-guided biopsy appears to be a complementary modality and is principally indicated in the case of occult or unclear breast lesions on MG/US, that are suspicious on MBI. The future indication is in targeted biopsies in patients with large heterogeneous tumours. Further studies are needed to define the accuracy of this biopsy procedure.

No MeSH data available.


Procedure steps of 99mTc-Sestamibi MBI-guided biopsy using a stereotactic localization system (GammaLoc®)
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Fig3: Procedure steps of 99mTc-Sestamibi MBI-guided biopsy using a stereotactic localization system (GammaLoc®)

Mentions: MBI-guided biopsy procedure is based on both preoperative imaging and intraoperative excision using 99mTc-sestamibi as radiotracer for target tissue localization, according to the radioguided surgery concept [23]. To date, methodological aspects of PEM-guided biopsy using 18F-fluorodeoxyglucose (FDG) have been described [24], whereas no article has yet been reported the steps in MBI-guided breast biopsy using 99mTc-sestamibi. For this latter modality, slant-hole collimator technology (GammaLōc® MBI localization system, Dilon Technologies, Newport News, VA) is used to calculate the lesion depth using a single-head system [13]. Biopsy is performed with the patient in seated position. The breast is placed between the detector and the paddle (CorreLocator™, Dilon Technologies, US) with light compression to reduce patient motion. A fiducial source using Cerium-139 (139Ce) is imbedded into the compression paddle as spatial reference point for determining the position of the lesion. The patient is administered with approximately 600 MBq of 99mTc-sestamibi into an arm vein contralateral to the breast lesion. Approximately 5 min after the injection, a scout image is performed using a parallel-hole collimator for positioning of the lesion. The breast lesion is in the exact position when it is assumed to be visible in the FOV of both the left and right stereotactic views. Subsequently, left and right stereotactic images are performed using a sliding slant-hole collimator (StereoView™, Dilon Technologies, US) for determining the grid localization (X, Y) and the depth (Z) of the lesion. Using this slant-hole collimator, 20 degree angle stereo views are required from both the left and right side (Fig. 3: Step 1). The location and the depth are clearly identified at the point where the angles intersect. Subsequently, the software (GammaLōc®, Dilon Technologies, US) calculates the X, Y, Z coordinates indicating the X and Y coordinates in the grid and the depth of the trocar needle in the guidance block (Fig. 3: Step 2). After injection of local anesthetic, the guidance block is placed in the paddle in the correct position. After the trocar needle is introduced into the sheath and the depth marker is set in the right position, the trocar needle is placed into the breast (Fig. 3: Step 3). Subsequently, a first image (pre-verification) is acquired in the energy window of 99mTc with the needle in place. Afterwards, the trocar needle is removed and replaced by a radioactive 139Ce source followed by a second image (post-verification) using the energy window of 139Ce. Both pre- and post-verification images are acquired using both slant-hole collimators located under the lesion to verify the correct position of the needle (Fig. 3: Step 4). After this verification step, the actual biopsy is performed using a vacuum-assisted device (VAD). The VAD is composed of a large bore needle with an internal cutting trocar that rotates 360 degree around the axis of the needle cutting 6 specimens from the target lesion, which is vacuum aspirated into the sampling chamber. A radiological marker is left behind at the biopsy site to enable further lesion excision or follow-up. Tissue sample activity is measured ex vivo using the parallel-hole collimator, followed by histopathological analysis. Finally, MG is performed to verify the correct marker position (Fig. 3: Step 5).Fig. 3


Methodological aspects of 99m Tc-sestamibi guided biopsy in breast cancer
Procedure steps of 99mTc-Sestamibi MBI-guided biopsy using a stereotactic localization system (GammaLoc®)
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5037160&req=5

Fig3: Procedure steps of 99mTc-Sestamibi MBI-guided biopsy using a stereotactic localization system (GammaLoc®)
Mentions: MBI-guided biopsy procedure is based on both preoperative imaging and intraoperative excision using 99mTc-sestamibi as radiotracer for target tissue localization, according to the radioguided surgery concept [23]. To date, methodological aspects of PEM-guided biopsy using 18F-fluorodeoxyglucose (FDG) have been described [24], whereas no article has yet been reported the steps in MBI-guided breast biopsy using 99mTc-sestamibi. For this latter modality, slant-hole collimator technology (GammaLōc® MBI localization system, Dilon Technologies, Newport News, VA) is used to calculate the lesion depth using a single-head system [13]. Biopsy is performed with the patient in seated position. The breast is placed between the detector and the paddle (CorreLocator™, Dilon Technologies, US) with light compression to reduce patient motion. A fiducial source using Cerium-139 (139Ce) is imbedded into the compression paddle as spatial reference point for determining the position of the lesion. The patient is administered with approximately 600 MBq of 99mTc-sestamibi into an arm vein contralateral to the breast lesion. Approximately 5 min after the injection, a scout image is performed using a parallel-hole collimator for positioning of the lesion. The breast lesion is in the exact position when it is assumed to be visible in the FOV of both the left and right stereotactic views. Subsequently, left and right stereotactic images are performed using a sliding slant-hole collimator (StereoView™, Dilon Technologies, US) for determining the grid localization (X, Y) and the depth (Z) of the lesion. Using this slant-hole collimator, 20 degree angle stereo views are required from both the left and right side (Fig. 3: Step 1). The location and the depth are clearly identified at the point where the angles intersect. Subsequently, the software (GammaLōc®, Dilon Technologies, US) calculates the X, Y, Z coordinates indicating the X and Y coordinates in the grid and the depth of the trocar needle in the guidance block (Fig. 3: Step 2). After injection of local anesthetic, the guidance block is placed in the paddle in the correct position. After the trocar needle is introduced into the sheath and the depth marker is set in the right position, the trocar needle is placed into the breast (Fig. 3: Step 3). Subsequently, a first image (pre-verification) is acquired in the energy window of 99mTc with the needle in place. Afterwards, the trocar needle is removed and replaced by a radioactive 139Ce source followed by a second image (post-verification) using the energy window of 139Ce. Both pre- and post-verification images are acquired using both slant-hole collimators located under the lesion to verify the correct position of the needle (Fig. 3: Step 4). After this verification step, the actual biopsy is performed using a vacuum-assisted device (VAD). The VAD is composed of a large bore needle with an internal cutting trocar that rotates 360 degree around the axis of the needle cutting 6 specimens from the target lesion, which is vacuum aspirated into the sampling chamber. A radiological marker is left behind at the biopsy site to enable further lesion excision or follow-up. Tissue sample activity is measured ex vivo using the parallel-hole collimator, followed by histopathological analysis. Finally, MG is performed to verify the correct marker position (Fig. 3: Step 5).Fig. 3

View Article: PubMed Central - PubMed

ABSTRACT

Purpose: This review aims to discuss the methodological aspects of dedicated molecular breast imaging (MBI) using 99mTc-sestamibi as radiotracer to guide biopsy of occult or unclear breast lesions on mammography (MG) and ultrasound (US) that are suspicious on MBI (BI-RADS criteria 4 and 5), including its advantages, limitations and future clinical applications.

Methods: Literature search was performed using the PubMed/MEDLINE database and “99mTc-sestamibi”, “biopsy” and “breast cancer” as keywords. The search was restricted to English language.

Results: There are few studies on 99mTc-sestamibi guided biopsy methods; to our knowledge, no full studies have yet been reported on clinical validation of this new biopsy procedure. This review describes technical aspects of 99mTc-sestamibi guided biopsy and discusses the advantages and limitations of this procedure in comparison with MG, US and MRI-guided biopsy.

Conclusions: MBI-guided biopsy appears to be a complementary modality and is principally indicated in the case of occult or unclear breast lesions on MG/US, that are suspicious on MBI. The future indication is in targeted biopsies in patients with large heterogeneous tumours. Further studies are needed to define the accuracy of this biopsy procedure.

No MeSH data available.