OverviewImage guided biopsies

Current gold standardsPET/CT guided biopsy

ProtocolAdvantages/disadvantagesUtilityFeasibility in Canada

Case Studies

Biopsy SignificanceIndividualized treatment regimen

Accurate tumor stageDistant mets

Patients in palliative situationsLess aggressive treatmentsBurden vs. quality of life

Cell-typing

Gold Standards Ultrasound CT

MRI

http://www.clinicalimagingscience.orghttps://iame.com http://radiology.ucla.edu

Gold Standard Modality Limitation

UltrasoundRetroperitoneal or deep pelvis,

masses surrounded by lung, bone, and/or bowel

CT Contrast is evanescent or valuable only in venous or arterial phase

MRIAbdominal masses require wide or open bore magnet, MR compatible

devices

• Modalities capable of identifying anatomical and structural changes

PET/CT Guided Biopsy

(Klaeser et al., 2009)

Effectiveness of PET/CT Guided BiopsyBegan with retrospective fusion

Previously acquired PET or PET/CT images to intraprocedural CT images

Target alignment not optimalNow moved to real-time imaging in the

PET/CT suite

ProtocolRoutine PET patient prepDiagnostic PET/CT image acquired

Eyes to thighsCan also use 185MBq dose for biopsy

Patient positioning adjusted1 CT bed (15cm) acquired, 1 PET bed (3mins)

acquiredEntry site marked and sterile drapes applied

ProtocolModerate sedationLocal anesthesiaBiopsy needles in place using unenhanced CT

scansFused with previously obtained PET scan

Biopsy needle placed in massRepeat CT and PET scan to confirm

Cytologist present2 hour observation

(Shyn, 2013)

UtilityFrom primary:

Melanoma LungLymphomaBreast

Metastasized to:BoneLiverSoft tissue

Head and NeckEsophagealColonPancreas

AbdomenLymph nodesLung

PET/CT AdvantagesCan indentify tumors without morphological

changesIf metabolic change has occurred“invisible” in U/S, CT and MRI

Identifies lesions with necrosisAble to identify more aggressive lesionsUptake lasts for hoursFDG not affected by procedure-related

complicationsCost-effectiveness

Cases Changed Types of Changes

Intramodality 22%

Chemotherapy with palliative

intent instead of curative intent

Intermodality 50%Systemic therapy chosen instead of

surgery

• If case remained unchanged, confidence in decision made was increased

DisadvantagesOccupancy of PET/CT machine

Room time = 87 mins – 141 minsBiopsy time = 37 mins – 87 mins

Radiation burden to patientRadiation burden to the interventionist Limited resolution

Dose

PET/CT Guided Biopsy 3.5 – 15.2 mSv

CT Component 54% - 81% of total combined dose

Low-Dose CTs in PET/CT

~ 8.2 mSv

CT Guided Biopsy 6.2 mSv – 23 mSv

DisadvantagesOccupancy of PET/CT machineRadiation burden to patientRadiation burden to the interventionist

Originating from the patient 10 uSv – 580 uSv @ 12-24 inches from pt.

Limited resolutionLess than 1.2cm in sizeMinimal amounts of metabolically active cells

Contacted 17 PET sites across Canada• Practicing interventional PET? Known future?• See a need?• Feasible (based on current workload)?

• Blue = Saw need/feasibility• Red = Required more

information

• White = No need/feasibility• Green = Retrospective

method

(Werner et al., 2013)

(Chakraborty et al., 2014)

ConclusionAiming for patient-centered careInterventional PET/CT offers:

EfficiencyBetter patient managementAccurate & timely diagnosisImproved patient outcomes

References Chakraborty, P. S., Dhull, V. S., Karunanithi, S., Verma, S., Kumar, R. (2014).

Malignant melanoma with cavitary pulmonary metastasis: Diagnostic dilemma resolved by FDG PET/CT guided biopsy. Indian Journal of Nuclear Medicine, 29(3), 196-197.

Ferrucci, J. T., Wittenberg, J. (1978) CT biopsy of abdominal tumors: Aids for lesion localization. Radiology, 129, 739-744.

Huang, B., Law, M. W., Khong, P. L. (2009). Whole-body PET/CT scanning: Estimation of radiation dose and cancer risk. Radiology, 251, 166-174.

Klaeser, B., Mueller, M. D., Schmid, R. A., Guevara, C., Krause, T. (2009). PET-CT-guided interventions in the management of FDG-positive lesions in patients suffering from solid malignancies: Initial experiences. European Radiology, 19(7), 1780-1785.

Klaeser, B., Wiskirchen, J., Wartenberg, J., Weitzel, T., Schmid, R. A. (2010). PET/CT-guided biopsies of metabolically active bone lesions: Applications and clinical impact. European Journal of Nuclear Medicine and Molecular Imaging, 37(11), 2027-2036.

Povoski, S. P., Sarolaya, I., & White, W. C. (2009). Comprehensive evaluation of occupational radiation exposure to intraoperative and perioperative personnel from 18F-FDG radioguided surgical procedures. European Journal of Nuclear Medicine and Molecular Imaging, 35, 2026-2034.

Rasmussen, S. N., Holm, H. H., Kristensen, J. K., & Barlebo, H. (1972). Ultrasound-guided liver biopsy. British Medical Journal, 2, 500-502.

Selzner, M., Hany, T. F., Wildbrett, P., McCormack, L., Kadry, Z., & Clavien, P. A. (2004). Does the novel PET/CT imaging modality impact on the treatment of patients with metastatic colorectal cancer of the liver? Annual Surgical, 240, 1027-1034.

Shyn, P. B. (2013). Interventional positron emission tomography/computed tomography: State-of-the-art. Techniques in Vascular and Interventional Radiology, 16(3), 182-190.

Silverman, S. G., Collick, B. D., & Figueira, M. R. (1995). Interactive MR-guided biopsy in an open-configuration MR imaging system. Radiology, 197, 175-181.

Sodickson, A., Baeyens, P. F., Andriole, K. P. (2009). Recurrent CT, cumulative radiation exposure, and associated radiation-induced cancer risks from CT of adults. Radiology, 251, 175-184.

Tatli, S., Gerbaudo, V. H., Feeley, C. M., Shyn, P. B., Tuncali, K., Silverman, S. G. (2011). PET/CT-guided percutaneous biopsy of abdominal masses: Initial experience. Journal of Vascular and Interventional Radiology, 22(4), 507-514.

Tsalafoutas, I. A., Tsapaki, V., Triantopoulou, C., Gorantonaski, A., & Paplliou, J. (2007). CT-guided interventional procedures without CT fluoroscopy assistance: Patient effective dose and absorbed dose considerations. American Journal of Roentgenology, 188, 1479-1484.

Werner, M. K. (2014). FDG-PET/CT-guided biopsy of bone metastases sets a new course in patient management after extensive imaging and multiple futile biopsies. British Journal of Radiology, 84(999), 65-67.

Wiering, B., Ruers, T. J., Krabbe, P. F., Dekker, H. M. & Oyen, W. J. (2007). Comparison of multiphase CT, FDG-PET and intra-operative ultrasound in patients with colorectal liver metastases selected for surgery. Annual Surgical, 14, 818-826.