Table 1.
Common and uncommon benign inflammatory and infectious causes of FDG uptake in oncology patients.
| Location | Etiology |
|---|---|
| Brain / CNS | Brain abscess |
| Toxoplasmosis | |
| Viral encephalitis | |
| Septic emboli | |
| Nocardia | |
| Meningitis | |
| Head and Neck | Lymphoid tissue, Waldeyer’s ring, palatine and lingual tonsils |
| Thornwaldt cyst | |
| Sinusitis (maxillary, ethmoid, nasal, frontal) | |
| Inflammatory jugulo-digastric lymph nodes | |
| Dental infections | |
| Parotitis | |
| Thyroiditis | |
| Mucositis after chemoradiation therapy | |
| Otitis media | |
| Otitis externa | |
| Mastoiditis | |
| Tracheostomy | |
| Thorax | |
| Lungs | Pneumonia |
| Atelectasis / collapse | |
| Opportunistic infections (pneumocystis, nocardia, fungal) | |
| Sarcoidosis | |
| Tuberculosis | |
| Rheumatoid nodules | |
| Bleomycin toxicity | |
| Septic emboli | |
| Post-radiation inflammation | |
| Pleura | Talc pleurodesis |
| Exudative pleural effusions | |
| Mediastinum | Chronic granulomatous disease |
| Sarcoidosis | |
| Tuberculosis | |
| Heart and large vessels | Endocarditis (abscess) |
| Myocarditis | |
| Sarcoidosis | |
| Infected prosthetic valves | |
| Iatrogenic (LVAD, surgical clips, pacemakers wires, AICD wires) | |
| Infected central lines | |
| Mycotic aneurysms | |
| Large-vessel vasculitis | |
| Miscellaneous | Esophagitis |
| Mastitis | |
| Breast abscess | |
| Fat necrosis | |
| Inflammatory axillary lymph nodes | |
| Abdomen | |
| Liver | Liver abscess |
| Hepatitis | |
| Cholangitis | |
| Gallbladder | Cholecystitis |
| Pancreas | Pancreatitis, pancreatic pseudocyst |
| Spleen | Granulomatous disease |
| Large and small bowel | Ulcerative colitis |
| Pseudomembranous colitis immunotherapy related colitis | |
| Bowel perforation | |
| Appendicitis | |
| Diverticulitis | |
| Small bowel ischemia | |
| Duodenitis | |
| Mesenteric adenitis | |
| Percutaneous drains and feeding tubes | |
| Stomach | Gastritis |
| Kidneys | Pyelonephritis |
| Renal abscess | |
| Retroperitoneal fibrosis | |
| Pelvis | Inflammatory inguinal lymph nodes |
| Salpingo-oophoritis | |
| Endometritis | |
| Prostatitis | |
| Epididymo-orchitis | |
| Musculoskeletal | |
| Bone | Discitis |
| Osteomyelitis | |
| Inflammatory degenerative disease | |
| Pressure sores | |
| Infected diabetic foot ulcers | |
| Orthopedic prosthesis infections and surgical hardware | |
| Chronic migratory recurrent osteomyelitis | |
| Muscles and joints | Dermatomyositis |
| Polymyositis | |
| Rheumatoid arthritis | |
| Rhabdomyositis | |
| Intramuscular abscess | |
| Vessels | Giant cell arteritis |
| Vasculitis | |
| Infected aortic-iliac-femoral grafts | |
| Infected A-V fistula | |
| Skin / subcutaneous soft tissues | Hidradenitis suppurativa |
| Wound infections | |
| Sebaceous cyst | |
| Acne | |
| Eczema | |
| Fournier’s gangrene | |
| Iatrogenic injection granuloma |