Lentigines vs Freckles: Key Differences
Lentigines and freckles are fundamentally different pigmented lesions: freckles (ephelides) are genetically determined, sun-induced macules with increased melanocyte activity but not number, while lentigines represent true proliferative lesions with increased melanocyte numbers and persist regardless of sun exposure.
Clinical Characteristics
Freckles (Ephelides)
- Small, light brown macules appearing exclusively on sun-exposed areas in fair-skinned individuals 1, 2
- Darken with sun exposure and fade in winter months 1
- Result from increased melanocyte activity without an increase in melanocyte number 2
- Never located on buccal mucosa or profusely around nostrils and mouth 3
- Typically appear in childhood in genetically predisposed individuals 1
Lentigines
- Well-demarcated, brown to dark brown macules on chronically sun-exposed skin (face, dorsal hands, forearms, upper back) 4
- Persist year-round regardless of sun exposure 1
- Show increased melanocyte number with elongation of rete ridges 2
- Predominantly affect middle-aged to elderly patients with fair skin and chronic sun exposure history 4
- Rarely solitary; presence of one lesion predicts development of additional lesions 4
Histopathologic Differences
Freckles
- Increased melanin production by existing melanocytes without melanocyte proliferation 2
- No architectural changes to the epidermis 2
Lentigines
- Increased melanocyte number confirmed on electron microscopy 2
- Moderate elongation of rete ridges 2
- Increased melanin pigment from basal layer to stratum corneum 2
- Mild inflammatory infiltrate with melanophages 2
- May contain giant melanin granules 2
Management Approach
Clinical Evaluation
- Perform careful examination to distinguish from lentigo maligna, which shows asymmetry, border irregularity, color variegation, and diameter >6mm 4
- Document concurrent signs of photodamage including actinic keratoses 4
- Critical pitfall: Always evaluate pigmented lesions carefully before any cosmetic treatment, as melanoma can masquerade as benign lentigines 5
Treatment Options
For patients seeking cosmetic improvement:
Topical Therapy
- Hydroquinone 4% is FDA-indicated for gradual bleaching of freckles and senile lentigines 6
Procedural Options
- Frequency-doubled Nd:YAG laser (532 nm) achieves >50% improvement in 80% of patients with freckles and lentigines in Fitzpatrick skin type IV 7
- Freckles show 40% partial recurrence at 24 months, while lentigines show no recurrence after laser treatment 7
- Focal trichloroacetic acid (TCA) peel: 50-65% TCA for solar lentigines (86% good response) and freckles (58% good response) 8
- Complications from laser include hypopigmentation (25%), mild textural changes (15%), and hyperpigmentation (10%), all resolving within 2-6 months 7
Critical Clinical Pitfalls
- Never perform laser treatment without first excluding melanoma - three cases of melanoma presenting for cosmetic lentigo removal were reported within a 2-month period at one laser center 5
- Do not confuse PUVA lentigines (more numerous, darker, occurring in both sun-exposed and protected areas) with solar lentigines in patients with psoralen plus UVA therapy history 4
- Distinguish from Peutz-Jeghers syndrome lentigines, which appear on buccal mucosa (66% of patients) - a location where freckles never occur 3
- Recognize that "freckle-like" lesions in neurofibromatosis are actually lentiginous macules with increased melanocyte numbers, not true freckles 2