Table 2.
Characteristics of systematic reviews including outcome data
| Systematic review (lead author, year) | No of included studies | Population | Organ of incidentaloma | Imaging modality | No of patients with incidental findings | No of incidental findings with diagnosis of malignancy | Malignancy type | No of incidental findings with diagnosis of other |
|---|---|---|---|---|---|---|---|---|
| Nayan 2014 | 30 | Oncology patients (n=17), asymptomatic patients (n=2), asymptomatic and oncology patients (n=11) | Thyroid | PET, PET/CT | 3659 | 477 | Papillary thyroid carcinoma: 391, follicular thyroid carcinoma: 28, Hürthle cell thyroid carcinoma: 9, medullary thyroid carcinoma: 8, anaplastic thyroid carcinoma: 2, metastasis: 28 | — |
| Treglia 2014 | 20 | Oncology patients (n=16), asymptomatic patients (n=2), unclear (n=2) | Colon | PET, PET/CT | 329 | 55* | — | — |
| Kousgaard 2017 | 26 | Oncology patients (n=26) | Colon | PET, PET/CT | 2121 | 332 | — | Inflammatory lesion: 73 |
| Treglia 2015 | 11 | Known or suspected cancer (n=7), asymptomatic and oncology patients (n=4) | Parotid | PET, PET/CT | 210 | 21 | Parotid cancer: 9, lymphoma: 8, metastasis: 4 | — |
| Bertagna 2014 | 9 | Known or suspected cancer (n=9) | Breast | PET, PET/CT | 292 | 137 | Breast cancer: 122 | — |
| Bertagna 2014 | 6 | Known or suspected cancer (n=2), asymptomatic and oncology patients (n=4) | Prostate | PET, PET/CT | 711 | 76 | Prostate cancer: 76 | — |
| Loh 2017 | 0 | Not suspected to have adrenal lesion (n=9) | Adrenal | Abdominal CT (n=6), unclear (n=1), abdominal CT/MRI (n=1), abdominal CT/MRI/US (n=1) | 1040 | 4 | Phaemochromocytoma: 4 | Cushing’s syndrome: 8, subclinical Cushing's syndrome: 120 |
| Xiong 2005 | 11 | Asymptomatic (n=2), colonic symptoms for investigation (n=9) | Extra-colon | CT Colonoscopy | 998 | 71 | Ovarian cancer: 5, lymphoma: 1, lung cancer: 5, renal cancer: 6, liver cancer: 1, pancreatic cancer: 4, choloangiocarcinoma: 1, bladder cancer: 1 | Aortic aneurysm: 22 |
| Morris 2009 | 15 | Asymptomatic (n=15) | Brain | Brain MRI | 1864 | 7 | — | Aneurysm: 72, cavernous malformation: 22, AV malformation: 7, definite demyelination: 9, possible demyelination: 4, arachnoid cyst: 100, colloid cyst: 2, Chiari malformation: 63, hydrocephalus: 7, extra-axial collection: 3 |
| Takashima 2017 | 10 (12 cohorts) | Asymptomatic (n=11), psychiatric (n=1) | Brain (n=11), extra-cerebral (n=1) | Brain MRI | 2661 | —† | — | Non-routine referral (urgent or semi-urgent (within weeks)): 6%, routine referral: 39%, no referral: 55% |
| Fernández-Balsells 2011 | 7 | Asymptomatic (n=7) | Pituitary | Brain MRI (n=2), unknown (n=1), brain MRI/CT (n=4) | 774 | 0 | — | Macroadenoma: 227 |
| Dunet 2016 | 11 | Undergoing cardiac MRI (n=11) | Extra-cardiac | Cardiac MRI | 1916 | —‡ | — | Major: 1104, minor: 1622 (*counting >1 incidentaloma per image) |
| Flor 2013 | 16 | Asymptomatic (n=1), suspected CAD (n=13), Mixed (n=2) | Extra-cardiac | Cardiac CT | 4922 | 29 | — | — |
| Jacobs 2008 | 6 | Asymptomatic (n=3), suspected CAD (n=3) | Thorax, abdomen, spine, and heart (n=3); extra-cardiac (n=3) | CT chest (n=3), cardiac CT (n=3) | 3272 | 19 | — | “Significant findings” defined as an imaging abnormality requiring further diagnostic investigation: 917 |
| Bach 2013 | 4 | Patients without breast lesions or symptoms (n=4) | Breast | CT chest | 234 | 116 | — | — |
| Ramadorai 2014 | 7 | Asymptomatic children (n=7) | Spine | MRI spine | 129 | 0 | — | Not consistently reported, when reported. Disc degeneration: 96, disc herniation: 10, spondylolisthesis: 8, disc protrusion/prolapse: 1, bone anomaly: 1 |
| Volpe 2016 | 17 | Asymptomatic patients or not suspected to have lesion (n=17) | Kidney | Unknown | 1530 | 324 | — | — |
| Anthoulakis 2014 | 4 | Asymptomatic patients or not suspected to have ovarian lesion (n=4) | Ovary | Abdominal US (n=3), PET/CT (n=1) | 363 | 91 | — | — |
AV=arteriovenous; CAD=coronary artery disease; CT=computed tomography; MRI=magnetic resonance imaging; PET= positron emission tomography; US=ultrasound.
*
Nine studies did not report the number of scans with incidental findings but reported the number of incidental findings that underwent biopsy (n=383) and how many of these were malignant (n=74).
†
Incidentalomas only presented as level of urgency, not stratified by pathology.
‡
Incidentalomas only presented as major (thoracic or abdominal malignancy or vascular pathology) or minor (thoracic or abdominal benign cyst).