the 8 snowmass 2017: pet/ct & nuclear medicine in · pdf filepet/ct of lymphoma (kevin l....

The 8 th | Snowmass 2017:

PET/CT & Nuclear Medicine in Clinical Practice

Thursday, February 23, 2017Westin Snowmass Resort • Snowmass Village, Colorado

Educational Symposia

TABLE OF CONTENTSTHURSDAY, FEBRUARY 23, 2017

Sentinel Node Scintigraphy (Kevin J. Donohoe, M.D.) ..................................................................................................... 159

PET/CT of Lymphoma (Kevin L. Berger, M.D.)............................................................................................................... 175

Challenging Chest PET/CT Cases (Don C. Yoo, M.D.) .................................................................................................. 189

The False Positive Problem with FDG PET: Improving Specificity with PET/CT (Paul Shreve, M.D.) ............................... 195

Challenging Abdomen and Pelvis PET/CT Cases (Don C. Yoo, M.D.) ........................................................................... 215

SAVE THE DATES - 2018 Winter Symposia

Lymphoscintigraphy - Sentinel Node

Imaging

Clinical Nuclear Medicine 2017

Kevin Donohoe M.D.

Division of Nuclear Medicine

Beth Israel Deaconess Medical Center

Harvard Medical School

Boston, MA

Conflict of Interest

•  I have no conflict of interest.

Take Home Points

•  Breast cancer injections should include peri-

tumoral injections

•  Tilmanocept is better tolerated by patients

than sulfur colloid

•  SPECT/CT is an important tool for specific

patient populations


•  Melanoma

•  Squamous Cell Carcinoma

•  Breast Cancer

•  Prostate Cancer

•  Penile

•  Colon

•  Etc .


•  Melanoma

– Superficial Spreading

– Acral Lentiginoid

– Lentigo Maligna

– Nodular

Signs of Melanoma – A,B,C,D

•  Asymmetry

•  Border (irregular)

•  Color (multiple shades of brown, red, or black)

•  Diameter (>6 mm)

161

Superficial Spreading Melanoma

•  Upper Back in men, lower legs in women

•  Age at diagnosis: 40 - 50

•  Shades of brown, bluish red with palpable borders

•  70% of melanomas

Superficial Spreading Melanoma

Acral Lentiginous Melanoma

•  Seen on the extremities - palms, soles, nail beds

•  Starts as a light brown spot on the lateral nail fold or

a vertical brown streak running the length of the

nail. When such a change is noted, a nail fold or

matrix biopsy is indicated.

Acral Lentiginous Melanoma

Lentigo Maligna

•  Usually the best prognosis

•  A slowly enlarging dark brown or black freckle on

the cheek of an elderly patient

•  Microscopically is malignant melanoma, but which

clinically runs an essentially benign course for years

(up to 25) until eventually invasive malignant

melanoma supervenes.

Lentigo Maligna

162

Nodular Melanoma

•  Seen at any site

•  Age: 40-50

•  Reddish purple, blue or black mixed with brown

•  Poor prognosis - prominent vertical growth phase

Nodular Melanoma

Melanoma - Risk Factors

•  High risk (>50 times nl population)

–  Persistently changing mole

–  Atypical moles in patient with two family members with

melanoma

–  Adulthood

–  > 50 nevi > 2mm

•  Intermediate risk (10 fold increase)

–  Family history of melanoma

–  Sporadic atypical moles

–  Congenital nevi (?)

–  Caucasian

–  Personal history of prior melanoma

•  Low risk (2 to 4 time normal)

–  Immunosuppression

–  Sun sensitivity or excess exposure

Melanoma Staging

Clark Level

I Confined to epidermis

II Invades but does not fill papillary dermis

III Through papillary dermis to reticular dermis

IV Reticular dermis

V Subcutaneous fat

Melanoma Staging

Thickness (mm) Overall MCCG*

< 0.76 96 99

0.76 – 1.49 87 95

1.50 – 2.49 75 84

2.50 – 3.99 66 70

>4.00 47 44

% Survival Breslow

* Melanoma Clinical Cooperative Group

163

RGP

VGP

Clinical-Pathological Correlation between RGP and VGP Melanoma in a Lesion where VGP Nodules Are Arising in RGP of the Superficial Spreading Type

From Robbin’s Pathologic Basis of Disease; Chapter: The Skin

When Should Sentinel Node Study Be Done in Patients with Melanoma?

•  When I get a request to do one.

•  ASCO Guideline (2012)

– http://jco.ascopubs.org/content/30/23/2912

– Melanoma > 1mm; < 4mm Breslow thickness

– Melanoma < 1mm if risk other factors are present

•  Lympho-vascular invasion

•  Mitotic rate ≥ 1/mm2

•  Vertical growth phase

•  Ulceration

•  Clark Level

164

Sentinel Node Logistics - Melanoma

•  EANM practice guidelines for lymphoscintigraphy and

sentinel lymph node biopsy in melanoma

–  October 2015

–  Endorsed by SNMMI

Injectate

•  Tracer

–  Filtered sulfur colloid

•  0.22 micron filter

–  Unfiltered sulfur colloid

–  Tilmanocept

–  Microcolloid

–  Nanocolloid

•  Antimony sulfide colloid

–  Albumen

•  Dye

–  Methylene blue

–  Lymphazurin blue

–  Isosulfan blue

•  Can decrease pulse oximetry > 2% in 33% of patients

Colloids Buffering the Colloid

•  Check pH of colloid from your

radiopharmacy.

Tilmanocept (Lymphoseek)

•  Multiple mannose units

– Attach to CD 206 receptors

– Macrophages

– Dendritic cells

•  7 nanometers

Injection Technique

•  Inject within 1.5 cm of lesion

•  Intradermal injection

•  Surround lesion

165

Imaging

•  Flow Images

– Depends on tracer, location

•  Delayed images

– 10 minutes

– Transmission views

•  Mark skin

– Co-57 spot marker

•  Surgery same day (usually)

Gamma Probe

Breast Cancer

•  Disease

•  Who gets sentinel node study

•  Comments on sentinel node studies in

general

Breast Cancer - Staging

Node Category Overall Survival Without Recurrence

All patients 60 47

Nodes negative 82 72

Nodes positive 40 25

1-3 nodes 54 34

4+ nodes 26 16

When Should Sentinel Node Study Be Done in Patients with Breast CA?

•  When I get a request to do one.

•  EANM/SNMMI Guideline

– http://snmmi.files.cms-plus.com/docs/

Final%20Breast%20Sentinel%20Node%20Guideline.

pdf

•  Women with invasive or microinvasive primary

and clinically negative axilla

•  Exceptions:

– Women >70 y/o with <2cm primary lesion that is ER+

– When sentinel node status will not change Rx

Sentinel Node Scintigraphy

•  Albertini - 62 pts with invasive BC (‘96 Florida)

– Blue dye and filtered SC injected around tumor

– Sentinel node removed

– Complete axillary node dissection carried out

– 92% of SLNs identified

– SC increased sentinel node detection from 73%

to 92%

– No pts with negative SLNs had positive non-SLN

nodes

166

Sentinel Node Scintigraphy

•  Paganelli, Veronesi Milan 1998

– Used various colloids

–  Intradermal and peritumoral injections

– Found fewer nodes in patients with larger colloid

(200 - 1000 nm)

Injection

•  Intradermal

–  Small volume (0.1 ml)

–  Low activity (100 uCi)

–  25 ga needle

–  2 sites around areola

•  Parenchymal (breast)

–  Larger volume (0.3 ml???)

–  Activity????

–  25 ga needle

–  4 sites around lesion (in lesion???)

–  ? Cold packs

Lymphatic Drainage of the Breast L Breast Cancer

Sentinel Node Imaging – Breast Cancer Sentinel Node Imaging – Breast Cancer

Anterior

167

Sentinel Node Imaging – Breast Cancer

LAO


Anterior


Left Lateral


Right Lateral

Tc-99m Co-57 Combined

Sentinel Node Imaging – Melanoma

168

Sentinel Node Imaging – Melanoma Sentinel Node Imaging – Melanoma

Sentinel Node

•  Uren – J Nucl Med 1993 – 203 patients –

Scintingraphy and clinical palpation identified

sentinel nodes in 98% of patients with melanoma.

–  22 patients showed drainage to 3 or more node groups.

–  Multiple lymphatic pathways seen in several patients.

Static

SPECT Head and Neck Issues

•  Proximity of injection to node bed

–  Inject smaller volume (0.05 cc)

–  Inject close to biopsy site

•  SPECT/CT imaging

– Helps identify obscured nodes

– Helps localize depth of nodes

•  Resect injection site first

•  Multiple node bed drainage

•  30% of the time positive nodes seen

in more than one node bed

169

Cervical Nodes

SPECT/CT

Sentinel Node – Lower Extremity Melanoma

170

SPECT/CT SPECT/CT

SPECT/CT

•  How useful is it?

– Tumor

•  Site

•  Cell type

– Surgeon

– How can you get information to the

surgeon

SPECT/CT

•  Better localization of sentinel lymph nodes

–  Small study in bladder cancer showed more sentinel

nodes with SPECT CT than with planar imaging.

–  Squamous Cell CA of head and neck – 40 patients -

Denmark

•  38% of patients showed additional relevant nodes with

additional planar and SPECT images

•  10% of patients had extra contralateral nodes identified

–  Breast cancer – 157 patients – Israel

•  Planar images alone negative for nodal visualization in 15%

of pts.

•  SPECT/CT alone was negative in 10% of pts.

–  Prostate cancer – Germany

•  SPECT/CT used to localize sentinel nodes for radiotherapy

•  4 of 6 patients would have had a “geographical miss” of

therapy to nodes in the perirectal area.

171

Hard Copy Communication Issues

•  Keep good relationship with the

surgeons

– Be aware of what they are doing with the

information you are providing to them

•  Images

•  Markings

– With probe

– ?Join them for surgery

•  Verify melanoma injection site with

surgeon if there is any doubt

Tumors

•  Vulvar cancer

•  Cervical cancer

•  Penile cancer

•  Head and neck cancer

•  GI tumors

•  Prostate cancer

•  Lung cancer

•  Thyroid (Italy - April

2006)

Problems With Other Tumors

•  Injection technique

– Site

– Timing

–  Invasiveness

•  Lymphatic drainage

•  Imaging, skin marking

172

PET Imaging of Lymphoma

Kevin L. Berger, MD

Director of PET/CT

PET/CT and Nuclear Medicine in Clinical Practice

Incidence of Cancer in the

United States*

Prostate 29%

Lung and bronchus 15%

Colon and rectum 10%

Urinary bladder 7%

Non-Hodgkin s

lymphoma

4%

Melanoma of the skin 4%

Kidney and renal pelvis 4%

Leukemia 3%

Oral cavity and pharynx 3%

Pancreas 2%

All other sites 19%

Women

678,060

Men

766,860

26% Breast

15% Lung and bronchus

11% Colon and rectum

6% Uterine corpus

4% Non-Hodgkin s

lymphoma

4% Melanoma of the skin

4% Thyroid

3% Ovary

3% Kidney and renal pelvis

3% Leukemia

21% All other sites

American Cancer Society. Cancer Facts & Figures 2007. Atlanta, GA: American Cancer Society; 2007.

Cancer Mortality in the

United States*

Lung and bronchus 31%

Prostate 9%

Colon and rectum 9%

Pancreas 6%

Leukemia 4%

Hepatobiliary 4%

Esophagus 4%

Urinary bladder 3%

Non-Hodgkin s

lymphoma

3%

Kidney and renal pelvis 3%

All other sites 24%

26% Lung and bronchus

15% Breast

10% Colon and rectum

6% Pancreas

6% Ovary

4% Leukemia

3% Non-Hodgkin s

lymphoma

3% Uterine corpus

2% CNS

2% Hepatobiliary

23% All other sites

Women

270,100

Men

289,550

American Cancer Society. Cancer Facts & Figures 2007. Atlanta, GA: American Cancer Society; 2007.

WHO Classification B-cell

•  Precursor B-cell neoplasms

–  B-acute lymphoblastic leukemia (B-ALL)

–  Lymphoblastic lymphoma (LBL)

•  Peripheral B-cell neoplasms

–  B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma

–  B-cell prolymphocytic leukemia

–  Lymphoplasmacytic lymphoma/immunocytoma

–  Mantle cell lymphoma

–  Follicular lymphoma

–  Extranodal marginal zone B-cell lymphoma of MALT type

–  Nodal marginal zone B-cell lymphoma

–  Splenic marginal zone lymphoma

–  Hairy cell leukemia

–  Plasmacytoma/plasma cell myeloma

–  Diffuse large B-cell lymphoma

–  Burkitt s lymphoma

REAL/WHO Classifications

for B-Cell Neoplasms Indolent

(Low Risk)

Aggressive

(Intermediate Risk)

Very Aggressive

(High Risk)

•  CLL/SLL

•  LPL

•  HCL

•  MZL

– Extranodal

– Nodal

– Splenic

•  Follicular lymphoma

•  PLL

•  Plasmacytoma/plasma cell

myeloma

•  MCL

• DLBCL

– Mediastinal large B-

cell lymphoma

– Primary effusion

lymphoma

• Precursor

B-lymphoblastic

lymphoma/leukemia

• Burkitt s lymphoma/

Burkitt s cell

leukemia

Variable Behavior

Abbreviations: CLL, chronic lymphocytic leukemia; SLL, small lymphocytic lymphoma; MCL, mantle cell lymphoma;

HCL, hair cell leukemia; LPL, lymphoplasmacytic lymphoma; MZL, marginal zone lymphoma; FCL, follicular cell

lymphoma.

Clinical Course of NHL subclasses

(WHO Classification)

6

MZ

L

SLL

*/C

LL

FL*

DL

BC

L*

MCL PMLBCL ALCL

PTCL

BLL

LL

Oth

er

22%

Indolent

(low grade)

Aggressive

(intermediate grade)

Highly aggressive

(high grade)

•  Slowly progressive •  Rapid clinical course •  Grows rapidly

31%

6%

2%

2%

6%

2%

2%

6%

5%

16%

Grades I, II- Indolent

Grade III- Agressive

Su

rviv

al if u

ntre

ate

d

Years Months Weeks

6%

MC

L

177

Hodgkin s Lymphoma

•  Clinically and biologically distinct

•  Bimodal distribution

•  About 8220 cases in the US

•  NHL:HL ratio of 8:1

Metabolic Phenotype Wong et al. JNM 2005

4317 357N =

Aggressive Behaviour of the Disease

AggressiveIndolent

60

50

40

30

20

10

0

-10

GROUP

Hodgkins Disease

NHL

58

95

99

2836

CMS Evidence Determination

•  Increased glycolytic metabolism is a fundamental

property of cancer cells, and thus there is really not any

cancer that is not FDG-avid. However, in general, low-

grade tumors that grow more slowly tend to be less FDG

avid than do their higher grade counterparts within a

given tumor cell type. Examples where this has been

demonstrated included low-grade sarcomas,

lymphomas, and gliomas.

–  http://www1.cms.hhs.gov/mcd/viewdraftdecisionmemo.asp?

from2=viewdraftdecisionmemo.asp&id=218&

Lymphoma Metabolic Phenotypes Wong CYO et al, MIB 2006

178

SUV limitations

•  SUV varies depending on partial

volume effects

•  SUV dependent on plasma glucose

concentration

•  SUV measurements are dependent

on reconstruction algorithms, uptake

time and scanner hardware

SUVpvc

SUV dependence on glucose

concentration •  EORTC(99): SUV change < -25% => Response

•  Scan 1: SUV=3; Glu=90

•  Scan 2: SUV=2; Glu=150

•  SUV change is -33% (significant change)

•  But 3/2 is similar to (90/150) -0.84

•  So change in SUV can be explained by change in

glucose level.

Courtesy of Oliver Wong, MD

Standardized Uptake Value

•  Recommend maintaining scan paradigms

(uptake time, reconstruction algorithm,

manufacture scanner type, etc.) for optimal

assessment of response.

•  Per ACR accreditation standards, report

glucose level, uptake time, injection dose,

etc. in technique

Lymphoma

•  We will review through a case illustration approach that

lymphoma presents with multiple different phenotypes:

small cell, follicular, marginal cell, diffuse large B-cell,

Hodgkin s, etc.

•  The FDG PET imaging characteristics reflect the

different phenotypes, and the clinical utility of FDG PET

is maximized by understanding the biologic behavior of

these different phenotypes.

Hodgkin s Lymphoma

•  29-year-old

•  Enlarged supraclavicular LN

•  Biopsy: classical HL, NS

•  B symptoms

179

HL, NS subtype

Low Power

Medium Power

Reed-Sternberg Cell

High Power

Hodgkin s Lymphoma Hodgkin s Lymphoma

Hodgkin s Lymphoma Hodgkin s Lymphoma

•  CT: stage IIB

•  PET/CT

– Stage IIIB

– IPS= 3

180

Does FDG-PET Add Additional Prognostic Information to

CT Staging in Lymphoma (NHL and HL) Patients

•  NHL = 110, HL + 26 patients

•  CT and FDG-PET were discordant in

30 %

– In half of them PET showed change of

stage.

Blanca Sanchez-Gonzalez et al, Blood (ASH Annual Meeting Abstracts), Nov 2008; 112: 4949.

Optimizing PET/CT •  Restaging of patients with lymphoma. Comparison of low dose CT (20 mAs) with

contrast enhanced diagnostic CT in combined [18F]-FDG PET/CT.

la Fougère C, Pfluger T, Schneider V, Hacker M, Bröckel N, Morhard D,

Hundt W, Bartenstein P, Becker C, Tiling R. Nuklearmedizin. 2008;47(1):37-42

and

•  J Nucl Med. 2007; 48 (Supplement 2):183P

• 

45 patients with non-Hodgkin lymphoma (n=35) and Hodgkin's disease (n=10)

were included into this study. Sensitivity/Specificity/PPV/NPV

•  LD-CT 66%/93%/76%/88%

•  CE-CT 87%/91%/78%/95%

•  PET 95%/96%/90%/98%

•  PET/LD-CT 94%/99%/97%/98%

•  PET/CE-CT 96%/99%/99%/99%

•  PET/CE-CT yielded a more precise lesion delineation than PET/LD-CT. This

was due to the improved image quality of CE-CT, increasing accuracy.

PET/CT Treatment Monitoring

•  Treatment with systemic chemo

– 2 cycles of ABVD

– No RT

Early PET Treatment Monitoring

Hodgkin s Lymphoma-Treatment Monitoring

– 2 months later Hodgkin s Lymphoma

181

Hodgkin s

Lymphoma

Early Interim 2-PET Scan Is Prognostically

Superior to International Prognostic Score

in Advanced-Stage Hodgkin's Lymphoma

Andrea Gallamini et al

Journal of Clinical Oncology, Vol 25, No 24

(August 20), 2007: pp. 3746-3752

Gallamini, A. et al. J Clin Oncol; 25:3746-3752 2007

Clinical outcome for patients according to International

Prognostic Score (IPS) group and PET results after two

cycles of ABVD


progression-free survival according to International

Prognostic Score (IPS) group


Progression-free survival according to IPS group and PET

results after two cycles of ABVD NHL-Follicular Grade 1

•  67-year-old

•  Left submandibular mass

182

PET

PET

SUV=5.4

SUVm=7.9

Biopsy: follicular NHL, grade 1

Follicular Lymphoma

Grade 1

Grade 1: 0-5 centroblasts/hpf; centrocytes

CD20 Bcl-2

Ki-67 Bcl-6

IHC NHL-Follicular Grade 1

•  Stage I

•  Received IFRT

•  Achieved CR

183

NHL-Restaging

•  Patient presents 2 years later with left

axillary mass

•  Restaging PET/CT

Restaging PET 3 years later

Restaging PET 3 years later

SUVm=15.9 Biopsy: Follicular NHL, grade 2

Follicular Lymphoma

Grade 2

Grade 2: 6-15 centroblasts/hpf

NHL-Restaging

•  Biopsy: Follicular NHL, grade 2,

•  Stage I

•  Received RT

•  No evidence of disease currently

184

PET- Subsequent therapy 4

months later

PET- Subsequent therapy 4

months later

End of therapy PET/CT status

correlates strongly with PFS

Amanda Cashen Blood (ASH Annual Meeting Abstracts), Nov 2008; 112: 371

NHL

•  66-year-old

•  Mesentric LN biopsy in 2003

•  Follicular NHL, grade 1

•  Treated with CVP

•  Restaging PET January, 2004

Follicular Transformed DLBCL Follicular Transformed DLBCL

SUVm=31.3

185

Follicular Transformed DLBCL

•  Biopsy showed transformed DLBCL

•  Treated with R-CHOP

•  Relapsed in 9/06

•  Liver biopsy: DLBCL

•  Treatment with R-ICE

Marginal Zone Lymphoma

(MZL)

59 year-old

Splenic MZL in 2001

Rituxan

Splenectomy in 2006

Splenic MZL MZL - Restaging

•  Large SQ mass in the right shoulder

area

PET MZL Transformed DLBC PET- Restaging, SUVm=16.1

•  3-9-07 on 226226

186

Pathology: Large Cell

Transformation Treatment

•  R-CHOP

•  Myeloid growth factors (pegfilgrastim)

was used during therapy

Restaging PET 4 months later PET Summary

•  Use of attenuation-corrected PET is strongly encouraged,

and the use of optimized PET/CT protocols.

•  Beware of potential pitfalls: brown fat activation, neck

muscle uptake, inflammation, G-CSF effect, etc.

•  Visual assessment alone is adequate for interpreting PET

findings as positive or negative though knowledge of

semiquantitative uptake may be valuable for recognizing

transformation or possible understaging secondary to

biopsy sampling error.

•  Mediastinal blood pool activity is recommended as the

reference background activity to define PET positivity for a

residual mass ≥ 2 cm regardless of its location.

PET Summary

•  Initial Diagnosis/Staging PET may direct biopsy and helps

characterize phenotype of lymphoma.

•  PET offers important prognostic information with regard to

response to therapy and is useful for characterizing a

mass as residual disease versus fibrosis.

187

False Positive Problem in FDG PET:

Improving Specificity with PET/CT

Paul Shreve, M.D.Advanced Radiology Services, P.C Spectrum Health Lemmen-Holten Cancer CenterGrand Rapids, MI USA

PET/CT & Nuclear Medicine in Clinical Practice 2017Smowmass, CO February 23, 2017

• Reimbursement/pre-authorization • Limited adoption in clinical practice guidelines

(such as National Cancer Care Network)• Referring physician confidence in clinical usefulness• Bad reads/reports• Few local champions

What is Holding FDG PET Back?

The Usual Suspects

6th Best Practices in PET/CT Symposium, Sonoma, CA Oct 3-5, 2013

• Most common critique of FDG PET is FALSE POSITIVE findings

• Reports do not address clinical question• Lack of correlation with other/prior

imaging studies in interpretation/report

What is Holding FDG PET Back?

Bad reads/reports

Cheson , B. The case against heavy PETing. J Clin Onc 2009; 1742-1743.

Whole Body FDG PET Imaging

• Concentrated in tissues proportional to glucose transport and metabolism

• Undergoes urinary excretion

2-Deoxy-2-[F-18]fluoro-D-glucose : FDG

FDG PhysiologicTracerDistribution

• Most cancers are hypermetabolic• So…. hot spots bad• Just identify hot spots not reflecting normal

organs/tissues• Report hot spots as cancer/possible cancer


What Could Be Simpler

197

•  Identifying hot spots on the FDG PET images is fairly easy

•  It is figuring out what the hot spots are that is the challenge

• The advent of PET-CT has made the task much easier, but not foolproof

• There is always a balance between sensitivity and specificity


But…all “hot spots” are not cancer

Shreve P, Anzai Y., Wahl R.L. Pitfalls in oncologic diagnosis with FDG PET

imaging: Physiologic and benign variants. Radiographics 1999; 19:61-77.

• Reconstruction artifacts• Benign sources of focal FDG

tracer uptake

False Positives in FDG

PET-CT Imaging

Benign Sources of Increased FDG Tracer Activity

4 iterations with 8 subsets

gaussian filter 5

2 iterations with 4 subsets

gaussian filter 7

Concentrated barium in rectosigmoid colon from prior upper GI series

causing extensive spurious apparent FDG uptake on attenuation corrected

PET images (used CT as attenuation map). No artifact on non-AC images

attenuation corrected non-attenuation corrected

198

Attenuation corrected OSEM

using contrast CT attenuation Non-attenuation corrected FBP

Subclavian vein contrast artifact can occur

when CT scanning protocol is not properly

optimized for whole body scanning

Contrast CT

•  Inflammation• Skeletal muscle• Brown fat• Benign soft tissue and bone tumors•  Isolated urinary tracer • Bowel activity•  Injection emboli


Benign Sources of Increased FDG

Re-staging of head and neck cancer

using PET/CT circa 2001

Abnormal soft tissue in right neck on recent CT

Patient post surgery and chemotherapy

Re-staging of head and neck cancer

Abnormal soft tissue on CT (arrowhead) has no corresponding

FDG uptake. Region of abnormal FDG uptake corresponds to

post- operative fistulous tract on CT scan (arrows)

• Activated leukocytes have elevated glycolytic metabolism

•  Infection and aseptic inflammation are associated with elevated FDG uptake

• FDG uptake typically moderate, but active granulomatous infection can be very hot

Infection and Inflammation

Whole Body PET-CT Imaging

• Read the CT! (pssst…it is not just a “localization scan”, never was)

• Priors, priors, priors! (PACS is here)• Clinical history, clinical history.• Take the time to do it right (easier

said than done these days)

FDG PET-CT Imaging

How to avoid benign hot spot false positive

199

Small focal pneumonia in left upper lobe

2010

2004

Diverticulitis

Diverticulitis with abscessSinus tract

200

Sarcoid Ovary

Hemorrhagic ovarian cyst

Pseudocyst at tail of the pancreas

Shreve , P. Focal fluorine-18 flouorodeoxyglucose accumulation in

inflammatory pancreatic disease. Euro J Nucl Med 1998; 25:259-264.

SUVmax = 6.8

HU = 18

201

SUVmax (of rim) = 3.8

HU = 26

Six weeks prior

FDG-PET: NSCLC, Mediastinal false positives

Caseating Granulomatous Infection

202

• False positive rate for lymph nodes in the mediastinum and neck as high as 10-15%

• False positive rate lower for abdominal/pelvic lymph nodes, appears to be < 5%.

• Tissue diagnosis should be obtained when possible to confirm a positive PET finding that substantially changes management

False Positive Lymph Nodes on FDG PET


• Talc pleurodesis• Subcutaneous fat and

intramuscular injection

Other inflammation related false positives


203

• Healing fractures can have modest FDG uptake, which can persist for weeks

• Degenerative joints, and certain joints such as sternoclavicular jointsand AC joints can show modest focal uptake

• Osteophytes rarely can have FDG uptake • Vertebroplasty• Myositis ossificans

Skeletal Inflammatory Uptake of FDG


Minimal FDG uptake in left AC joint due to degenerative change

Rib fracture

Sacral insufficiency fracture in patient being staged for non-small cell lung cancer

Multiple vertebralplasties and insufficiency fractures

Breast cancer with left hip pain

204

Attenuation corrected Non-attenuation corrected Myositis Ossificans

•  Inflammation• Skeletal muscle• Brown fat• Benign soft tissue and bone tumors•  Isolated urinary tracer • Bowel activity



209

Insulineffect on FDGmuscle uptake

Skeletal muscle physiologic FDG uptake

205




Functional Anatomy - Brown Fat Uptake


• Brown adipose tissue is thought to be involved in mammalian thermal regulation

• Adrenergic stimulation causes rapid glucose uptake and metabolism to generate heat

• FDG uptake is seen in residual adult brown fat in response to cold or adrenergic output

• Brown fat FDG uptake is most commonly seen in fat at the base of the neck and shoulders, thoracic paraspinous fat, but can be present in mediastinal and upper abdominal fat as well Physiologic brown adipose tissue FDG uptake

at neck and shoulders in young anxious patient

206

Physiologic brown adipose tissue FDG uptake at typical location of base of neck and shoulders

Physiologic brown adipose tissue FDG uptake in paraspinous fat along thoracic spine

Physiologic brown adipose tissue FDG uptakein less common location of upper abdomen

Physiologic brown adipose tissue FDG uptake at the neck and shoulders and mediastinal lymphoma

Functional Anatomy – Hibridomas


• Benign brown fat tumors have been know to pathologists

• Rare, usually seen at shoulder, knees• Are very hot but have typical CT appearance• FDG uptake can vary over time • Liposarcoma is in the differential

hiberdoma

207




• Warthin’s tumor in parotid gland• Benign pituitary adenomas can very hot• Benign bone lesions including histiocytic/giant

cell containing lesions

Benign Tumors


Aoki J, et. al. Radiology 2001; 219:774-777

Warthin s tumor of leftparotidgland

208

May 2011 September 2010

May 2011 September 2010

Pituitary Adenoma Pituitary Adenoma

Normal palatine tonsil FDG uptake Normal adenoid FDG uptake in a 16 year old

209

• Adrenal nodules are common (5% on CT)• 80% nodules are adenomas• 40%-57% adrenal nodules benign in patients

with known malignancy• Adrenal also fairly common site of metastasis

(lung, breast , melanoma, renal, colon, thyroid)• Primary adrenal cancers rare

Adrenal Masses


Benign adrenal adenoma

• Benign adrenal adenomas can exhibit low FDG tracer activity, sometimes greater than liver

• CT criteria for adrenal adenoma (HU < 10) can be helpful

• Gets difficult with small nodules with modest uptake in setting where adrenal metastasis possible (ie lung cancer) – prior CTs if available

Adrenal Masses


Blake MA, et al. PET/CT for Adrenal Assessment. AJR 2009; 195: W91-W95Anatomically normal adrenals with FDG uptake




210

Focal FDG uptake in retroperitoneum Normal urinary FDG in ureter

Ureter identified on CT confirms focal FDG uptake is due

to urinary tracer, not an abnormal lymph node

Bilateral bladder diverticula urinary FDG tracer activity Bilateral bladder diverticula urinary FDG tracer activity




Right and transverse colon physiologic FDG uptake

211

Right and transverse colon physiologic FDG uptake

• An isolated intense focus of FDG uptake in the colon warrants further investigation (colonoscopy) as this is associated with villous adenomas and carcinomas generally > 1 cm in size

• CT may not be revealing, although occasionally a nodule or mass is seen

Focal Intense FDG Tracer Uptake in Colon


Incidental adenocarcinoma of the sigmoid colon

• Same as with other nuclear medicine exams

• Remember registration in axial planes between PET images and CT images may not be perfect


Injection blood clot emboli artifact

• False positive findings can be reduced by careful attention to CT findings, prior imaging studies, and clinical history

•  Inflammation, particularly of lymph nodes, is a source of unavoidable non-specificity

• A close working relationship with referring clinicians is key to reducing the fall-out of false positive and false negative FDG PET-CT interpretation and reporting

False Positive Findings on

FDG PET-CT

Conclusions

212

VailFebruary 4 - 9, 2018Vail Marriott Mountain Resort & SpaVail, CO

Snowmass

February 11 - 16, 2018The Westin Snowmass Resort Snowmass Village, CO

*Snowmass February 18 - 23, 2018The Westin Snowmass ResortSnowmass Village, CO

*Dates and Location Subject to Change.

If you enjoyed this meeting and would like to share it with your colleagues, these lectures and thousands more are available for streaming on-demand atONE

FREEHOUR

WINTER 2018 SYMPOSIA

Educational Symposia

SAVE THE DATES

edusymp.com • docmeded.com (800) 338-5901 (Toll-Free, U.S. & Canada) • (813) 806-1000 (Direct)

5620 West Sligh Avenue Tampa, Florida 33634-4490

the 8 snowmass 2017: pet/ct & nuclear medicine in · pdf filepet/ct of lymphoma (kevin l....

Documents