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Nonmelanocytic Lesions
Published in Ashfaq A Marghoob, Ralph Braun, Natalia Jaimes, Atlas of Dermoscopy, 2023
Sarah N. Hocker, Harold S. Rabinovitz, Margaret C. Oliviero, Ashfaq A. Marghoob
Solar lentigines are sharply circumscribed, uniformly pigmented macules that are located predominantly on the sun-exposed areas of the skin, such as the dorsal aspects of the hands, the shoulders, and the scalp. These lentigines are a result of hyperplasia of keratinocytes and melanocytes, with increased accumulation of melanin in the keratinocytes. They are induced by ultraviolet light exposure. Unlike freckles, solar lentigines persist indefinitely. Nearly 90% of Caucasians over the age of 60 years have these lesions. Due to the increased prevalence of lentigines in the elderly, these lesions are sometimes referred to as lentigo senilis. However, younger individuals who have a tendency to burn after ultraviolet exposure can also develop lentigines after acute or prolonged ultraviolet light exposure [3,16].
Benign Neoplasms
Published in Ayşe Serap Karadağ, Lawrence Charles Parish, Jordan V. Wang, Roxburgh's Common Skin Diseases, 2022
Abdullah Demirbaş, Ömer Faruk Elmas, Necmettin Akdeniz
Clinical presentation: Lesions are small hyperpigmented macules with a diameter generally not exceeding 5 mm. They are located anywhere on the trunk, extremities, genitals, and mucous membranes. (Figure 19.1) The number of lesions may range from few to many. Lentigines may also be seen in patients with xeroderma pigmentosum, Peutz-Jegher disease, Addison disease, Carney complex, LEOPARD (lentigines, ECG changes, ocular hypertelorism, pulmonary stenosis, abnormal genitalia, growth retardation, and deafness), Laugier Hunziker, and Bannayan-Riley-Ruvalcaba.
Carney Complex
Published in Dongyou Liu, Handbook of Tumor Syndromes, 2020
Skin lesions (e.g., lentigines, café-au-lait spots, blue nevi, freckling; 77% of cases) may emerge at birth and usually represent the first manifestation of CNC (Figure 51.1) [23]. Lentigines appear as multiple small (0.2–2 mm), flat, poorly circumcised, brown to black macules (or slightly raised macules, similar to nevi, in African Americans) typically around the vermilion border of the lips, on the eyelids, ears, and the genital area. Blue nevi are larger (up to 8 mm), blue to black, dome-shaped lesions that are less common than lentigines. A subtype of blue nevus is epithelioid blue nevus (EBN), which shows intensive pigmentation and poorly circumscribed proliferative regions with associated dermal fibrosis. Although EBN is very rare in the general population, it is relatively commonly found in patients with CNC. Café-au-lait spots and depigmented lesions are occasionally observed in CNC. In general, cutaneous pigmentary lesions tend to increase in intensity, number, and distribution around puberty, and fade after the fourth decade [1,2].
Split-face comparison of the efficacy of picosecond 532 nm Nd:YAG laser and Q-switched 755 nm Alexandrite laser for treatment of freckles
Published in Journal of Cosmetic and Laser Therapy, 2022
Shao-Yin Ma, Ye-Qing Gong, Wen- Jun Zhang, Bi-Hua Liang, Yue-Ming Li, Zhi-Min Xie, Hui-Lan Zhu
Both lasers showed statistically significant improvement of freckles and satisfaction scores. QSAL performed better than PS532. The better curative effect, the greater patient satisfaction. The differences between the two groups were statistically significant. Because picosecond lasers can destroy melanosomes with only minimal tissue damage, slight whitening of the lesion is the preferred immediate skin reaction and endpoint. Stopping the treatment at the point of slight whitening should promote safe and effective treatment of solar lentigines (9). It may have been easier to judge the clinical endpoint and design parameters after Q-switched Alexandrite lasers treatment than following the picosecond 532 nm Nd:YAG laser. The findings were much the same in Yang’s work (10). Yang et al. compared the efficacy and safety of a picosecond Alexandrite laser and a Q-switched Alexandrite laser for the treatment of freckles in Chinese patients. There were no significant differences in lesion clearance rate or patient satisfaction.
Antibacterial, Antioxidant and Melanogenesis Inhibitory Activity of Auraptene, a Coumarin from Ferula szowitsiana Root
Published in Nutrition and Cancer, 2022
Ensiyeh Charmforoshan, Ehsan Karimi, Ehsan Oskoueian, Mehrdad Iranshahi
The melanin production process (melanogenesis) takes place in cells known as melanocytes. Melanin production is necessary for skin pigmentation against UV irradiation. On the other hand, the increased production of melanin might cause several skin disorders including lentigines, nevus, freckles, melisma, and age spots. Kojic acid, linoleic acid, arbutin are tyrosinase inhibitors and used for the treatment of hyperpigmentation. Generally, the skin-whitening agents are tyrosinase inhibitors possessing toxicity against melanocytes and indicated adverse side effects. Thus, the development of natural tyrosinase inhibitors with low toxicity is necessary (28). In the present experiment, auraptene isolated from Ferula szowitsiana root possessed high inhibitory activity against tyrosinase enzyme with the IC50 values of 29.7 μg/mL however this value was lower than that of kojic acid as a reference standard with a respective IC50 value of 14.7 μg/mL (Figure 5).
Laugier-Hunziker syndrome: complete clearance of mucosal lentigines with a single session of Q-Switched Nd:YAG laser
Published in Journal of Cosmetic and Laser Therapy, 2019
There have been numerous case reports of successful laser treatment of hyperpigmented macules in Laugier-Hunziker syndrome – the lasers used have included Q-Switched Alexandrite, Er:YAG, and Q-Switched Nd:YAG laser. Ferreira et al. reported successful clearance in a middle-age Caucasian lady with the Q-Switched Nd:YAG laser(7). Ozawa et al. reported 100% clearance of lesions with one session of Q-Switched Alexandrite laser with no recurrence at 6 months in one patient(8). Zuo et al. treated 22 Chinese patients of Laugier-Hunziker syndrome with 81.8% patients achieving an excellent result after only one session of Q-Switched Alexandrite laser(9). Three to six sessions were done for the remaining patients all of whom ultimately achieved complete clearance. Papadavid and Walker treated two cases of Laugier-Hunziker syndrome with the Q-Switched Alexandrite laser. Complete clearance was attained in one session however one case had a recurrence of two lentiginous macules 6 months later – these were successfully retreated(10). There is one case report of treatment of extensive mucosal lesions with the Er:YAG laser – complete clearance was attained, however 50% of the lesions recurred after 1 year(11).