11/1/2014. Radiologic incidentalomas Ordering pitfalls Newer technology and applications

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1 Bilal Tahir, MD Gitasree Borthakur, MD Indiana University School of Medicine Department of Radiology & Imaging Sciences October 31, 2014 ACP 2014 Dr. V. Aaron Nuclear Dr. S. Westphal Nuclear Dr. K. Sandrasegaran Abdomen Dr. K. Walker Breast Dr. H. Kipfer Breast Dr. E. Beckley Radiologic incidentalomas Ordering pitfalls Newer technology and applications Adrenal nodules Low density liver lesions Pancreatic cysts Renal cysts 1

2 6% of CTs (10% in > 70- years age) 1 show adrenal incidentaloma (AI) 3-5% of AI are hormonally active 2 78% of AI are likely to be adenomas 3 70% of AI are lipid rich 1. Kloos RT, et alendocr Rev 1995;16(4): Young WF Jr. N Engl J Med 2007;356(6): Song JH, et al. AJR 008;190(5): Noncontrast CT for? renal calculi a Rt AI Density = 1 HU a lipid-rich adenoma Retrospective review of 1639 patients with suspected carcinoma of unknown primary 1 6 month later hypertension + low serum K + Underwent sampling (Lt, Rt adrenal veins) a functioning adenoma = Conn syndrome CT does not assess functionality of adenoma 95 (5.8%) had adrenal gland involvement at presentation Only 4 (0.2%) had isolated adrenal met (all > 6 cm size) Retrospective review of 973 patients (not known to have malignancy) with 1049 AI on CT 2 1-year imaging follow up or 2-yer clinical follow-up on all No adrenal malignancies seen Bottom line: < 4 cm nodule without known cancer or other metastatic lesions has very small (< 0.2%) likelihood of malignancy 1. Lee JE. Surgery 1998; 124(6): Song JH, et al. AJR 2008;190(5): May 2008 Jun 2008 Jun 2012 Guidelines for Managing AI Berland LL, et al. J Am Coll Radiol 2010;7(10): Left AI with high density (41 HU on Pre). No known cancer. Should have had follow-up unenhanced CT or MRI. Instead had biopsy which was not indicated without h/o cancer. Pre Enh Del CT 4 years later shows no change in size. Bladder cancer and bone met 5 cm left adrenal nodule. Likelihood of met is high. Should have had PET- CT or biopsy Instead had nonindicated triple-phase CT with showed indeterminate washout. AI less than 1 cm may be ignored When 1-4 cm, risk of malignant AI in noncancer patient is very low (< 0.2%) Lesion > 4 cm, require biopsy, PET-CT or resection 2

3 Low risk < 40 years No malignancy No risk factors or history of chronic liver disease No liver-related symptoms Average risk: > 40years, o/w same as low risk High risk: Malignancy with known ability to metastasize to liver Berland L, et al. Managing Incidental Findings on Abdominal CT: White Paper of the ACR Incidental Findings Committee. J Am Coll Radiol 2010;7: If low or average risk: no further follow up If high risk: CT or MRI in 3 to 6 months If any of these features worrisome Ill-defined margin HU > 20 units Size change from prior Heterogenous enchancement No worrisome features No follow up (all risks) Any worrisome feature Follow up (typically MRI in 3-6 months) Low density definitely benign features: no follow up Low density suspicious features Low risk: 6-month follow up or MRI Average risk: Immediate MRI High risk: Biopsy or MRI Guidelines for managing incidental liver lesions depends on patient's risk for malignancy Most small lesions < 1.5 cm in low or intermediate risk patients do not need follow up 3

4 Low risk: Asymptomatic cyst < 2 cm Intermediate risk Cysts > 3 cm Main PD dilation of 5-9 mm Thick septa (> 2 mm) Nonenhancing mural nodule High risk Pancreatic head cyst with CBD obstruction Main PD 10 mm Enhancing mural nodule If cyst < 2 cm: follow up in 1 2 years (preferably MRI) No growth = stop surveillance If > 5 mm growth = treat as intermediate risk Jan 2008 Mar 2010 Simple cyst (Bosniak Type I) imperceptible wall rounded Work up: none 4

5 Mildly complex (Bosniak type 2) Thin septa Thin calcification Work up: none Confusion over when to order a screening mammogram vs. diagnostic mammogram Screen Women with no complaints Typically doctor order NOT needed, doctor name needed Order needed if history of breast cancer Order needed if younger than 35 Implants considered screen Diagnostic Clinical concern Lump, thickening, skin changes, nipple retraction, clear or bloody nipple discharge, FOCAL pain Must have a doctor order Radiologist on site and will completely work-up abnormality and give results at that time Ordering diagnostic mammograms for common breast complaints 5

6 Diagnostic mammogram not needed for Galactorrhea Diffuse breast pain Cyclical breast pain History of benign breast biopsies Skin lesions Confusion over when to order a breast US vs diagnostic mammogram ACR appropriateness criteria: Women 30 and older always get a mammogram first then a focused ultrasound if indicated Women under 30 get a FOCUSED ultrasound first Confusion over when to order a screening breast MRI Screening for High-risk patients ACS: High risk women Greater than 20% lifetime risk should get an MRI and a mammogram every year Women at moderately increased risk 15% to 20% lifetime risk should talk with their doctors about the benefits and limitations of adding MRI screening to their yearly mammogram Low to average risk Less than 15% lifetime risk should NOT get screening MRI Ordering a CT without contrast in addition to CT with contrast when not needed 6

7 Metastatic cancer work-up / follow-up Trauma (head & C/T/L-spine without) Abdominal / pelvic / chest pain, weight loss, infection, inflammatory processes, most other indications For arterial stenosis, CTA Some indications require multiple post contrast phases (HCC screening triple phase, pancreatic dual phase) Forgetting to order a CT without when needed in addition to a with contrast CT Aortic dissection Adrenal mass workup (may only need noncontrast) Renal mass workup HCC follow-up status post non-surgical treatment AAA status post endovascular stent graft repair CT Urogram CT Cystogram Ordering wrong protocol CT or excluding body part For aortic dissections/aneurysms CTA chest ordered but forget to order CTA abdomen/pelvis CT renal protocol renal mass vs renal stone Ordering CT stone protocol when meant to order CT urogram For abdominal pain forgetting to order CT pelvis in addition to abdomen For PE. Ordering a CTA chest Confusion over CT IV contrast administration and chronic renal insufficiency 7

8 On hemodialysis --- full IV contrast dose For GFR > 45, full IV contrast dose For GFR of and not on hemodialysis, IV hydration (250 ml NS prior and 250 ml after), decrease IV contrast dose by 20-25% For GFR of 30 or less and not on hemodialysis, no IV contrast Confusion over when to order a post contrast spine (C, T or L-spine) MRI Malignancy Infection Prior spine surgery Confusion over when to give enteric contrast for CT Gastrografin --- if pt < 150 lbs, recent GI surgery/enteric leak Water --- pancreatic protocol Volumen --- enterography 8

9 FDA approval 2011 Screening and diagnostic modality Same breast positioning and standard compression Acquires images at several angles in a short amount of time and reconstructs the images into thin, high-resolution slices Removes challenges from overlapping tissue Increases interpretation time Increases dose Images acquired at multiple angles of a compressed breast (as little as 4 seconds) as the detector and anode move around the breast Information is then reconstructed into slices Not widely available Expensive technology Increase interpretation time No reimbursement Insurance companies consider tomo investigational No CPT code January,

10 No consensus/recommendation All screening patients Subset of screening patients Dense High-risk Diagnostic add-views Tomosynthesis Increase Cancer Detection Rate Decrease Recall Rate Decrease patient anxiety Decrease biopsy rate Increase positive predictive value Increase cost-effectiveness Risk assessment Role for PCP High-risk clinics Molecular Breast Imaging (MBI) Single and Double detector systems commercially available Breast Specific Gamma Imaging (BSGI) refers to single detector studies Not effected by breast density Smaller dose may be possible with double-detector systems Systemic ionizing radiation exposure still main concern for use in screening Positron Emission Mammography (PEM) Similar efficacy with MRI in biopsy proven cancer: Sensitivity: PEM = 85%; MRI = 98% Specificity: PEM = 74%; MRI = 48% Systemic ionizing radiation still a concern May be a good alternative for patients with contraindications to MRI SPECT obtains biologic activity in 3D plane Conventional nuclear medicine images in 2D plane CT provides anatomic imaging SPECT-CT combines both imaging modalities Cardiac Parathyroid Bone Thyroid Cancer Lymphoscintigraphy 10

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14 Calcifications Type II endoleak Use radiologist as a consultant rather than lab service. Radiologists can add value to patient care. Incidental adrenal nodules under 1 cm can be ignored. Those 1-4 cm may be followed up in 1 year. Most small low density liver lesions < 1.5 cm in low or intermediate risk patients do not need follow up. Asymptomatic pancreatic cysts < 2 cm require MRI follow-up to demonstrate 1-2 yr stability. Most renal cysts are simple or mildly complex (thin septa or calcification) and require no further imaging. Be aware of common pitfalls when ordering radiology exams Constant growth in radiologic technology and applications Feel free to with questions: btahir@iupui.edu hmtkko 14