TADA Method for Dermoscopy
The TADA (Triage Amalgamated Dermoscopic Algorithm) is a simplified 3-step dermoscopic algorithm designed for high sensitivity skin cancer detection, particularly useful for family physicians and frontline clinicians. 1, 2
Step I: Identify Unequivocal Benign Lesions
The first step requires unequivocal identification of dermoscopic features for one of three specific benign skin lesions: 1
- Angioma - Look for red-purple lacunae or red-blue lagoons 1, 3
- Dermatofibroma - Assess for firm palpation with dimpling and central white scar-like area 1, 2
- Seborrheic keratosis/lentigo - Identify milia-like cysts, comedo-like openings, or fissures/ridges 1, 3
If any of these three benign lesions can be confidently identified, the lesion is classified as benign and no further steps are needed. 1, 2
Step II: Assess for Architectural Disorder
If Step I features are absent, evaluate for architectural disorder, defined as disorganized or asymmetric distribution of colors and/or structures. 2
The specific criteria to assess include: 2
- Asymmetry of structures or colors
- Disorganized distribution of dermoscopic features
- Chaotic arrangement of pigmentation patterns
Step III: Evaluate for Malignancy-Specific Features
If architectural disorder is present, assess for specific dermoscopic criteria indicative of malignancy: 2
- Starburst pattern 2
- Blue-black or gray color 2
- White structures (shiny white structures, regression) 2, 4
- Negative network (angulated lines around hair follicles) 2
- Ulceration 2
- Vascular structures (dotted, polymorphous, or atypical vessels) 2, 4
The presence of any of these features warrants biopsy or specialist referral. 2
Diagnostic Performance
TADA demonstrates a sensitivity of 94.8% and specificity of 72.3% for malignant skin lesions after basic dermoscopy training. 2
- Sensitivity for skin cancer increases from 62.5% to 88.1% following TADA training 3
- Specificity reaches 87.8% post-training 3
- Diagnostic accuracy improves from 76.4% to 90.8% for all lesions after introductory training 1
Critical Clinical Pearls
Previous dermoscopy experience is not required for effective TADA use - studies show no significant association between prior training and diagnostic sensitivity (P = 0.13) or specificity (P = 0.36). 2
Dedicated teaching time for benign lesions is essential - focusing on the three Step I benign neoplasms before malignancy training significantly improves overall diagnostic accuracy. 3
TADA has limitations with micromelanomas - 40% of melanomas ≤5.0 mm do not present melanoma-specific patterns, and the algorithm achieves only 64% detection of these small lesions compared to 96.61% for larger melanomas. 4