Dr.Mustafa ahmed Alazam

1. Benign Breast Disease
on PET/CT imaging

2. Terminology
• Benign conditions in breast may mimic breast
carcinoma on PET/CT.
• Inflammatory lesions are most common cause
for benign FDG uptake in breast.

3. Top differential diagnosis
• Top differential considerations for benign FDG
uptake in breast include:
- poorly FDG-avid tumors such as DCIS, lobular
carcinoma.
- small tumors (< 2.5 cm)

4. IMAGING
• PET/CT is used in conjunction with other imaging modalities,
such as mammography, sonography, and breast MR to make
diagnosis.
• Common benign causes for FDG uptake on PET include
dense breast tissue, fat necrosis, lactation, silicone
rupture/granulomas, infection, trauma, recent interventional
procedures, and benign breast conditions such as
fibroadenomas and fibrocystic change.
• Benign breast conditions without significant FDG uptake
include cystic lesions, cystic tumors, intramammary nodes, and
some benign breast tumors .

5. Nuclear Medicine Findings

6. ○ Normal breast tissue
– FDG uptake is proportional to tissue density and hormonal/menopausal status.
□ Dense breasts have significantly↑ FDG uptake compared to fatty breasts.
□ Breasts in premenopausal patients demonstrate↑ FDG uptake compared to postmenopausal
patients.
□ ↑ SUV in central breast as opposed to peripheral breast (more fatty tissue in peripheral breast).
– Breast density typically decreases with increasing age; however, no significant correlation
between age and normal breast tissue FDG uptake.
fatty breasts
Dense breasts

7. Fat necrosis
– May exhibit ↑FDG uptake from various traumatic events/interventions.
□ Most common etiologies: Breast trauma, diagnostic interventions & surgical procedures.
– Sterile inflammatory process 2° to previous breast trauma, diagnostic procedure, or surgery.
□ TRAM reconstruction: Typically ↑ FDG uptake along incisional margins 2° to fat necrosis.
– ↑ FDG uptake 2° to metabolically active inflammatory cells.

8. Lactation
– Lactating glandular tissue: Intense, nearly symmetric FDG uptake
□ Slight asymmetry between breasts normal.
– Breast tissue proliferates with lactation and involutes with breastfeeding
cessation.
– Increased FDG uptake physiologically related to infant suckling.
□ Intracellular trapping of radiotracer in active glandular tissue.
– FDG uptake returns to normal within 3-4 weeks of breastfeeding cessation.

9. Implants/silicone rupture
– Leaking silicone implants or silicone granulomas: ↑ FDG uptake
(typically intense).
□ Saline implants more rarely demonstrate FDG Uptake.
□ MR remains modality of choice for silicone rupture.
– ↑ FDG uptake at rim of calcific capsulitis.

10. Infection
– Acute or chronic, including overlying skin.
– ↑ FDG uptake 2° to mastitis, abscess, TB and fungal Infections and post-
radiation.
Reactive axillary, internal mammary, axillary lymph nodes: ↑ FDG uptake.
– Activated inflammatory cells demonstrate increased glucose transporters.
□ Same physiologically as malignant cells.

11. Post intervention
– Focal ↑ FDG uptake due to core biopsy, recent surgery or
radiotherapy.
□ May persist for several weeks
– Leukocyte infiltration of granulation tissue involved in wound
repair.
□ Resorption of necrotic debris and hematoma.

12. Benign breast conditions
– Variable ↑ uptake in fibroadenomas, phyllodes tumors, fibrocystic
change, and inspissated cysts.
□ ↑ FDG in fibroadenomas and phyllodes tumors 2° to high proliferation
and rapid growth.
– Ductal ectasia, typical/atypical hyperplasia, apocrine Metaplasia.
□ Often mildly ↑ FDG above normal glandular tissue
phyllodes tumor

13. DIFFERENTIAL DIAGNOSIS:
Poorly FDG-Avid Breast Cancer
• Concurrent chemotherapy or radiation treatment
○ May have decreased uptake in areas of viable tumor.
○ Predictive of good response to chemotherapy/radiation.
• Lobular or tubular carcinoma
○ Typically low FDG uptake 2° to low-grade tumor
○ With aggressive behavior, may show ↑ FDG uptake
• Ductal carcinoma in situ (DCIS)
○ Variable linear/branching areas of FDG uptake
– Greater sensitivity with high-resolution positron emission
mammography (PEM) units than conventional PET scanners.
• Small tumors
○ Partial volume effects decrease measured SUV in tumors < 2.5
cm in diameter (false-negative).

14. THANK YOU